Thursday, February 28, 2013

New Plane of Reality (V)

Well a week has gotten by me since the last post, and most of those intervening days have featured time working on the planer or at the very least thinking about working on the planer. It's been a bit of a saga. Hmm, maybe I wouldn't have it any other way?

Wiring is similar to plumbing, in a few different ways. Both trades deal with flow and distribution,  can be lucrative occupations, can be done basically out of a van, and involve fairly complex systems of parts, some of which can be fitted together and some of which can not. Both trades are fairly pleasant activities when installing new systems, but can be decidedly unpleasant or even dangerous when working on older systems in poor condition which may have been improperly installed. I used to work as a foreman in an irrigation company in my tender and impressionable 20's, and one thing I always remember happening was going into the supply trailer in the morning and carefully stocking all the parts I could imagine requiring on the job site. Sure enough, when I got to the site it would only be a matter of time before I discovered some small piece which I had overlooked to bring - a small piece, but invariably an item which was critical to the system being installed or repaired. I find wiring much like that, and kept running into some new development as I installed the parts which would require a part I didn't have on hand. Or where I had thought an existing part was one size and on that basis had obtained items to match it, and then get up close to the part and find out it was a different size. So, lots of running around getting this and that. But finally - finally - I completed the installation of a new 3-phase circuit, using 8-gauge wire in 1" EMT (electro-mechanical tubing). It was yesterday that the last connection was completed.

With the piping in place, I flipped the circuit breaker. Good news as it stayed in the 'ON' position, so the circuit was functional. No fires were breaking out as far as I could tell. Not that I was worried about that, but, as they say, one step at a time. Checkpoint to checkpoint, dotting the i's and crossing the T's. I sidled over to the planer and plugged it in. All good. I checked that the compressor was on and there was 45psi indicated on the back of the machine, and things looked good. I walked around to the front of the machine and gave the master switch a turn to the 'ON' position. I was hoping for lights, camera, action, however nothing happened. It was full-on, still life with planer. A whole lotta nothin'.

So, I decided to troubleshoot and got out my multimeter. It's a newer digital type of meter that I picked up from Radio Shack a few months back, and 99% of the time when I am using it the task is checking continuity using the ohms circuit and the 'beep' function. This time I wanted to measure voltage. I swiveled the clicker dial on the front of the meter over to the 'V' category, for Volts, and proceeded to see if I had power at the outlet. Not only could I not detect any voltage, but the meter was crazily bouncing around various numbers. I decided to go and check on a 115v. outlet I knew to be live. Still couldn't measure any voltage. Wha-?

I dicked around for the next 15 minutes trying to figure out what was going on but just couldn't seem to use the meter to read voltage. I was close to tearing my hair out. I put the meter to one side and looked into other sorts of deductive reasoning avenues I might take. First of all I checked other circuits coming out of the load center to see if they were providing power. They were. Then I swapped wires from my dust collector to the same fuse block for the planer, to see if the fuseblock was working properly. It was. Still, without a means to measure voltage, there wasn't much I could do to investigate further. Then my neighbor Joe showed up. He's working on a 15' wooden dinghy build next to my shop area. I told him about my frustrations in trying to read voltage with my digi-meter and he mentioned that he had a multimeter kicking around. It was one of those old time units with the Bakelite plastic case and the analog gauge. My dad used to have one just like it. It worked. A few moments later I was able to establish that the new circuit functioned perfectly and that I had three powered legs, 120v. each, coming into the back of the machine. I also had power at the master switch on all three legs, and when the switch was snapped to the 'ON' position, there was power on the output side of the switch as well.

I went home as I thought it would be jolly helpful to take a look at the wiring diagrams for the machine. While at home I discovered how to get my multimeter to operate properly - I merely had to push the same button, oh, about 6 times in succession to set the meter to read AC volts in the correct range. It came as a relief to learn that I had a perfectly functional multimeter and had not lost my mind.

Today, looking at the electrical section of the planer cabinet, I could see that one of the primary overload protectors was not hooked up at all. Funny how you can't see the unfamiliar object very well at first. But then, I'm a guy and sometimes have trouble finding stuff in the fridge - items which my wife can locate in a matter of seconds. It was right in front of me of course. Biology and evolution have made me the blind monster that I am, what can I say?

Here's the front of the machine with the electrical access door open, to give you some idea:


If you look at the picture more closely, you can see at the top of the opening there is the transformer. Below that is the main overload protector for the motor, called 'FS-1'. It wasn't hooked up at all. Now having eyes to actually see, perceptual blindness fading slowly but surely, I realized that the wires from that protector had been re-connected to a smaller overload protector which basically hung off of the wiring harness and was spliced in with wire nuts. It was obvious that this other protector had been spliced in after the fact, and was not an original factory install. I'm starting to believe those stories about the Carib Indians not being able to see Columbus's ships.

Speaking of wire nuts, I made the mistake at the electrical supply store the other day of asking for them by the name which they are often referred to in Canada: marettes. Yep, got the blank stare from that attempt, but at least didn't have anyone burst out laughing at my 'crazy' English.

Now that I was armed with a functioning multimeter and the relevant wiring diagrams, I could tear into the problem. The overload protector which had been spliced in was thus removed:


Then of course I hooked the original overload protector back up, which was a slightly awkward job, especially since my right shoulder is still healing from surgery and I don't have full use of my right arm yet. Got 'er done though.

I also realized I had to re-wire some connections on the back of the motor, as it had been converted from 230v to 460v by the previous owner. I took the large metal cover panel off the front of the planer and could access the motor's electrical box easily. Swapped over the connection to the original configuration, and buttoned that up once again.

I thought I had gone through everything, so I closed up the machine again, plugged the receptacle back in, and went around to the front to turn the master switch to 'ON', expectations running high. Nothing happened.

I opened the electrical access again and had another look. I found that there was a contactor unit which had a sort of push button on it. I pushed the button and to my surprise the motor came to life. A glance told me that the head was turning the wrong direction, so I went to the back of the machine, unplugged the power and swapped a couple of leads to obtain the correct orientation. Back to the  access hatch, I confirmed I could turn the main motor on, and shut it off, using the internal contactor, but that was all. I then started measuring voltage here and there and soon discovered that the transformer wasn't putting the correct voltage out. I peered a little closer at it and could just make out some writing on top which indicated one slot was for '460v' (which had a wire hoked up to it) and an adjacent slot which said '230v' (which had no wire connection. Aha! I swapped the wire over from one to the other. I closed up the access panel and flicked the switch:


Eureka! It's alive! I could move the table up and down, and turn the machine on and off. The variable speed could be adjusted. I fired up the dust collector and shoved some pine into the machine - it planes! That means the Tersa head appears to be okay!! I am so relieved, I can't tell you. Well, actually I AM telling you. Whew!!

Note the above digital setting of 2.625". The setting can be adjusted in 0.001~0.002" increments using a push button. I ran a piece of pine through at the above setting and then put the calipers on it to see how accurate it was:


 If it can reliably plane to +/- 0.005" I will be quite pleased.

What shocked me about the planer was how quiet it is, both when idling and when feeding wood. I don't need to wear hearing protection, and I mean that. I'm not talking about toughing it out, it is seriously quiet. The dust collector is far noisier. I've never used a planer before that was so quiet. The cut quality was also excellent. After running some pine through on an angle left and right a few times, just to be sure to seat the knives, I ran some Jatoba through and it planed it perfectly and without giving any indication that it was any sort of struggle, which is a far cry from my Makita shoebox planer.

Here's a look at the back of the machine, showing the small GMC compressor I have hooked up:


And here's a look at the dust collection piping - this hook-up required cladding a metal column in some 2x6 lumber, taking what looked to be an hour or two of work - attaching dust piping and electrical to the column - and turning it into more than a day of futzing about:


The power cord for the overhead light which you can see transiting across will be wired up a bit more cleanly in the next day or two.

And last but not least, a view from the front, to show the happy pairing of SCM S-630 planer and Hitachi CB100FA bandsaw, both with stout construction, digital readouts and more than adequate power:


In the above picture the S-630's table is about as low as it can go, which is indicated to be a hair over 11.875". The table condition was excellent, and the bed rollers operate smoothly and are easy to move out of the way. I will rarely use them as I invariably employ dry material that has been faced on the jointer. They might be handy sometime though. The green panel on front with 'scmi' written on it is the one that you remove to access the motor's electrical box.

At long last the fundamental solid wood machining operations of jointing and planing are well accommodated by my shop's equipment.  I'm very happy to have cleared this hurdle. Now I'll be on the hunt for a tablesaw, and then a shaper. If work continues to go well for 2013 I should be able to obtain a saw in the next 10 months. We'll see.

Thanks for coming by the Carpentry Way.

Thursday, February 21, 2013

New Plane of Reality (IV)

The adventure continues with my newly-received SCM S-630 planer. I've been doing a fair bit of research on Tersa heads, past and present, including looking over the original patents, been in touch with people in Italy, in Switzerland, the US and Canada. Both MBM in Italy and the fellow at tersaknives.com in Canada agreed that the head has to come out and be sent to the factory to be re-assembled and rebalanced. I had a talk with a tech rep at SCM in Georgia, and he suggested, however, a way where I could try to replace the bolts and carefully fit the knives back in. His explanation didn't make total sense, as he talked about tightening the gib plate down to where it wouldn't let the knives insert, then unscrew the bolts gradually, counting the turns, until the knife would just insert.

But, all things considered, it made sense to at least try and re-set the bolts holding the plates and see if the head will lock up the knives properly and plane wood cleanly. If it won't then I'll be looking at either sending the head back to the factory, or buying a new head. Prices for new insert knife heads did not excite me. Here's the breakdown of what I found:
  • SCM factory replacement: $3380.00, lead time of 6~8 weeks
  • Byrd Shelix head: $3495.00, lead time of 10~12 weeks
  • Terminus head: $3800~4000.00, lead time of 8 weeks
  • Tersa factory head: $3400.00, lead time of 3~4 weeks
Uh, ouch! Still researching costs on other options too, but for the time being, I decided to try a re-fit of the plates, as that was by far the least costly solution. These gib plates were not removable after I took all the bolts out, so I wasn't able to get in there and clean every nook and cranny as I might have liked. So, I gave the head another once over with rust cleaning chemical, then sprayed a product called PB Blaster in to the gibs, which is a penetrating solvent intended for loosening sticky mechanisms. After letting that soak in a while, I used compressed air to blow the grooves as clean as I could. Then I chased all the threads and put the bolts back in.

Contrary to the advice of the SCM tech, it was not possible to even fit the knives at all until the gib plates were well tightened down. I think he must have been thinking about some later or earlier style of head which had some sort of spring loading underneath the gib plate, who knows?  Anyway, I was pleased to find that the gib plate needed to be fully tightened before the knives could even be slid into place. I had a small piece of tersa knife blade about 3/4" long which I used as a gauge and to slid along and clean the inside space some. It seemed to work well. After a few hours of work i had all the knives back in, and all the bolts in, save one.

One bolt had snapped during dis-assembly, so I was left with the grim prospect of removing a frozen, red loctite-fixed bolt which was buried under the gib plate. I've done enough wrenching on rusty vehicles, both cars and bicycles, to have had a few run ins with the dreaded rusty snapped off bolt. I've come to a few strategies for getting them out, techniques which generally work well for me, 9 times out of 10. Your mileage may vary of course, but I thought it might be of interest to at least some readers to run through how I tackled this problem.

The bolt in question is 6mmx16mm, and had sheared off just underneath the bolt head, leaving a fairly flat topped stub in the bore. I started with a small drill, about 3/32", and carefully drilled a hole as close to the middle of the bolt as I could. The result:


It's a little off center, but not too bad.

Next, in the hope of softening that red Loctite (the 'permanent' thread-locking chemical), I used a heat gun for a while:


Not sure how much that would help, but it was worth a shot.

Next, I grabbed a LH-spiral cobalt drill bit, 1/8" size, put the drill in reverse, and drilled out the hole:


I've learned not to bother with the 'Easy-out' type of screw extractor, as they can all-too-easily snap off in the hole and give you an even bigger headache than you started out with. They are made of a very hard and brittle steel, so if one breaks off, there's no ready way to drill through the remnant.

Continuing on, I vacuumed out the hole as best I could:


Next, on to a slightly larger LH cobalt drill:


I repeated the same steps again, until I was drilling out the hole with a 7/32" LH drill bit. This bit is a little shy of the ideal size bit for drilling the hole if you wanted to later tap it - a 13/64" bit is the right size for that - however the 7/32" bit removes most of the waste while accommodating some slight off-centeredness with the drill hole.

The nice outcome with these LH spiral bits is that once you have punched out most of the bolt, the resistance of the bolt falls away and then the drill bit will catch the bolt and unscrew it right out, like this:


I find this sort of work a bit stressful, so I was quite elated when I felt the bolt give up its fight and came back out of the hole. As it does, it tends to clean up the threads too!

Then on to cleaning up the threads with a fresh tap (this was necessary as my other tap snapped unexpectedly when starting to clean out the hole and I had to spend 15 minutes teasing the tap remnant back out):


Then the bolt could be reinstalled, at least temporarily:


Whew! Made it through without excessive trauma. What a relief.

Now, the bolts I removed from the head originally are of uncertain condition, given that one snapped and others were removed with an impact driver and did put up a fight. Those bolts might be stressed and could fail prematurely when re-tightened, so a wise course is to toss them I think. I picked up some 6x16mm bolts from the local hardware store, however I cannot expect these to be decent quality (just like most of the stuff in the hardware store these days, sad to say). Metric bolts come in several strength grades, the toughest of which is 12.9, So, I found an online supplier, based in Massachusetts, called Bolt Depot, that stocked grade 12.9 bolts in a 6x16mm size, and to boot their price was about 1/3 of what the local hardware store was charging for cheap quality bolts. So I ordered up a full set of 36 bolts to replace all the cap screws - these I will put on with blue Loctite and sequentially torque down to a setting something like 10% lower than the bolt is rated for, to be on the safe side.

Meanwhile, I have hooked the air compressor up to the planer and completed the dust collection piping for the machine as well. The planer is now on the floor in final position. I have close to 12 feet of room on the infeed end, which should be plenty.

I peeked in at the side of the planer motor and could make out its data plate. Turns out that I have a 9Kw, or 12 h.p. machine, not a 10 h.p. machine. The more the better - yeah baby! This planer was pretty lavishly optioned, and I appreciate that.

I did some calculations given the motor's horse power, 208v., 3-phase power supply from 100' away, motor efficiency which I estimated at the standard 85.5%, and motor power factor of 0.85, means that the machine will consume about 34 amps peak, and require an electrical feed with 8 gauge wire.  I have hooked up a new power cable to the machine, using 8 gauge, 4-strand jacketed wire. Since I am crossing over the 30 amp threshold for the first time, equipment-wise, I can't use the same plugs and receptacles that my other 3-phase machines happily operate on. Ideally, I would go to a 40 amp plug and socket, but they don't seem to make those. After 30 amp, the next size up is 50 amp, and a 50-amp rated plug and socket cost me $110.00. I have the receptacle mounted on the post next to the planer and need to put in some EMT conduit. I did some conduit wire fill calculations, and 4 strands of 8 gauge wire need a 1" conduit size.You can only fill 40% or the conduit's interior area with wire, by provisions of NEC (electrical code).

I think I should be able to put power to the planer in the next couple of days, and I am excited to see it come alive and have fingers crossed that the Tersa head will work as it should. All for now, over and out - thanks for your visit!  On to post 5

Wednesday, February 20, 2013

French Connection 12

I had moved my drawing of the three-legged bench, a layout project intended for the study of placing Saltaire crosses with their pieces in various rotations in between posts and beams which are not orthogonal to one another, to the point where I was about to start in on the third pair of braces. Then I had a re-think about it, and decided I really wasn't going to be happy enough with the aesthetics to devote the time to building the piece. So, back to the drawing board - either that or abandon ship.

Stepping back and considering the issues relevant to the layout of this piece, i was able to achieve a few breakthroughs in understanding in terms of the basic associations and slopes between members. As i result of that, I was able to try an idea I had a long while ago about making the tripod beam assembly from pieces which had a bend at their ends. This bend brings the end of the beam into alignment with the post below, which gets rid of the annoying off-set interface between the two sticks, an annoyance I could never really come to terms with.

Here's a look at where things stand in the virtual world at least - I've nearly finished with brace set one, the 'faisant lattis entre elle' set:


Actually, starting the layout from scratch, with different slopes for the posts and the inclined brace pair, led to some further breakthroughs in understanding, after hours of puzzlement, as I came to see that I had not properly understood a portion of the layout in my previous go-rounds. This method of Mazerolle's involves the production of 'footprints', which are like projections of the stick's cross-sections onto the floor - you can see one in the above drawing at the left, a grey parallelogram just near the foot of the post. Once you obtain the correct parallelogram footprint, you are able to draw an accurate plan view of the braces and determine their intersection points with the plan views of the posts and beams, and from there construct the cuts for the ends of the braces.

Mazerolle's drawing is fairly cryptic, as most of the geometrical development lines are omitted, and the text's explanation is not of much help once deciphered. So, a fair amount of head scratching is involved. I found that the method I had used previously for developing the footprints on this side of the bench was not working in the new drawing. Eventually I realized that I had understood the method incorrectly, and had produced the wrong shape of parallelograms in my previous sketches. Measuring the 3D constructed sticks, I found they had cross sections of 93˚/87˚ instead of 90˚. Even though the sticks weren't square in section, they will construct from 2D to 3D just fine and lap one another cleanly, so it all looked good. But it wasn't. One of those aha! moments ensued, and I was able to figure the method out correctly a while later.

I have figured the footprint method out, and feel like I have a solid understanding of it. The same can not be said for other aspects of the layout, though I'm getting there. In terms of understanding, my grasp of the problems, I may be hanging from my fingertips on the ledge, so to speak, but I feel like my grip is slightly strengthening at least.

Clearing away some of the lines, here is a pic giving a better look at the revamped design:


Next, a plan view - I'm thinking about a glass top again for this project, so a view somewhat like this will be apparent, given the overall height of 20":


Once all the brace sets are in it starts to look a bit like a snowflake.

One more:


Other slight changes I have made involve the tenons on the top of the posts and on the ends of the tripod beams, which have been squared back on one side to facilitate assembly. I have had some further ideas about joinery for connecting the braces to the beams, and will be exploring those ideas further as I move the drawing along.

So, what do you think - does it look any better with the bent tripod beams? Even if the aesthetics don't seem to show any great improvement overall, the bent tripod cleans up the junction between post and beam and that was the main purpose.

All for now, thanks for dropping by. Comments always welcome.

Monday, February 18, 2013

New Plane of Reality (III)

Well, today I was able to talk to a guy named Norbert in Kaslo, B.C. who runs tersaknives.com. He's Swiss and definitely knows his stuff. I told him what I had done and as I feared, the cutterhead will have to come out. It was a bit of a mix of good and bad news actually. Removing the gib plates from the head means that they would need to be sent back to the factory (ie., SCM) or to Tersa in Switzerland, to be put back on and be properly rebalanced. However, he said I had taken a reasonable step given the rust on the cutterhead and the sticky operation of the floating wedges. He said that anytime you buy a used machine that has been sitting for a while, like the one I bought, then it is wise to at least budget for a new Tersa head. The Tersa head needs to function flawlessly, and if there is any question about whether those floating bars will smoothly slide up and lock the knives in place, it is wiser to err on the side of caution and install a new head. Imagine the damage if one of the bars didn't lock the knife properly and then you fed wood into it - that could cause all sorts of expensive carnage. So, it looks like I'll may be getting a new Tersa cutterhead, and it will possibly be one of the newer types that does not have the bolt-on gib plates.

I spent a few hours today working on the machine, trying to remove the cutterhead. The head rides in a pair of NSK 6208DU bearings, which are 80mmx40mmx18mm. These bearings are fixed laterally in the carrier by a pair of large spring clips. Finding a tool to remove these large spring clips took two trips, out to four different stores, and eventually I picked up a pair of long neck bent-tip needlenose pliers that did the job. Finding quality industrial tools in my area is problematic and I hate not having the right tool for the job. Removing those clips allowed me to move the head laterally side to side, however I now need to remove the pulley on the end of the arbor and I am unsure whether the Allen head screw which holds the pulley on comes off clockwise or anti-clockwise. I'm suspecting clockwise, however I'll check with SCM first before heaving on it.

I will also talk to a few other technician about the head and see if there might be other opinions on the matter. I have learned from Edward Papa at Simantech, Inc. that SCM does not make the Tersa head-  it was actually another Italian company called MBM. MBM makes all of the Tersa 'Monoblock' style heads for the Italian machines, just as Martin makes the Tersa heads from the German machinery market. So, I've sent MBM an email to see what they say, and will talk to SCM USA tomorrow. In another day or two I should have a good idea as to which course of action to take.

Meanwhile, I've moved my planer over to sit next to the Hitachi resaw, and I think it will work well in this location:


The home of the green monsters, the new Fenway Park perhaps.

Another view:


I should be able to tuck them in a little tighter, which will entail moving the down-pipe for dust collection back a foot or two. I've also shifted the bandsaw to the side about a foot and brought it forward slightly.

All for now - thanks for visiting! On to post 4

Sunday, February 17, 2013

New Plane of Reality (II)

Getting the planer off the pallet required a little head-scratching as I lack a forklift. In the past when taking machines off of pallets I've made use of pivoting the center of mass around, using lots of blocks and supports, Johnson bar, etc., and gradually maneuvering the machine down to the ground. This time, I decided upon a different approach, realizing that the machine had lifting hook points and could be hung from an overhead beam, which measures something like 12"x14". I used the pallet jack to get the machine up as high as I could, attached a couple of 1-ton ratchet straps, and gradually lowered the pallet jack until the straps took the weight, keeping an eye on the beam above:


The beam didn't make even a creak. A few minutes later I had the machine off the pallet and onto the pallet jack with a couple of blocks:


A few maneuvers later, the intermediate blocks were out and the machine was directly on the pallet jack and I pushed the behemoth over to the position I had in mind.

Trouble is, the position I had in mind, nestled next to the jointer, wasn't looking quite as good as I had hoped. The height of the SCM planer is just a bit higher than the Martin planer, and that means that a board coming out of the machine could potentially run into the jointer's fence support arm, and that's a meeting I would most certainly want to avoid with 10 hp doing the pushing. So, I could raise the jointer up another inch to clear, but I would rather not actually, as i like the working height as it is. Considering the tilt of the floor in that location (it's an old mill building with wonky wooden floors), I am guessing that by the time I have the planer level I might need to bring the jointer height up more like 1.5" or even 2". So, that's not looking quite so promising at all. The width of the planer also makes space around the adjacent router table a little tighter than ideal.

I'm thinking I might move the planer over to a spot next to the bandsaw, which would still be just a couple of steps away from the jointer outfeed, plus I do have a 6" dust collection pipe there which is the size I need for the planer. I've already cut the dust pipe at the jointer and places a 45˚ lateral in the line, but it isn't riveted and taped yet so it would be no big deal to put a clean run of pipe back in place. Also, the location next to the bandsaw would mean a decrease in EMT metal wiring conduit of about 25', plus attendant couplings and so far, and the associated 100' of wire (25'  each for 4 wires).

I think I just convinced myself to move the planer over by the bandsaw - this blogging can help me organize my thoughts at times!

I set to work on the planer wiring and fairly quickly determined where it had been modified so a to operate on 460v. I simply had to remove one wire and re-connect another wire, as well as reset some dials on the overload protectors. I'm not entirely sure about the exact settings on those dials, so I'll call SCM early in the coming week to see what they say.

Wiring sorted, I vacuumed the interior of the machine. There was dust in there - not too much though. I'm guessing some of it simply migrated in from other parts of the shop where it was located, as a planer generally produces chips, not dust.

Then I decided to clean the planer's cutterhead. I thought it was mostly dirty with pitch residue, however a scrub with turpentine did little to change the appearance and I was realizing, to my chagrin, that it was actually surface rust on the cutterhead. I got out some rust-dissolving spray chemical and started to scrub the cutterhead with that, using a 3M abrasive cloth. After a moment I realized the work would be a lot safer if I removed the knives. I got out the wooden block and tapped on the wedge bars, but I found them a bit sticky and not as easy to move as on the Martin, which after all is brand new. I got the bars loose on one knife and pulled the knife out, but it was also kind of stuck in there and didn't slide out as easily as I might like. Of the three remaining knives, one was about the same as the first and the other two were a bit easier to remove. I decided that it would be a good idea to clean in and around those floating lock bars as it is critical to the functioning of the Tersa system that the bars move be able to slide into position absolutely smoothly. The bars however cannot be extracted due to their shape. I saw that the knife on the head was fixed to a bar which was held in place with about a dozen metric cap screws, and I thought if I removed the bars that I could then pull out the rest of the knife-locking mechanism. The Allen-head cap screws were in pretty tight, but I managed to remove them pretty easily using an impact driver. I worked my way around the head, and on the second-to-last bolt, I had the bolt head snap off. Damn! So that was one problem to deal with, though I'm reasonably confident I can fix it.

The drag (besides the one snapped bolt) was that the bar I had 'freed' still would not come out, nor would it allow the wedge bars to come out, though all the parts were loose. A bunch of work for nothing perhaps. Grrr.

I returned to my scrubbing with the rust-removing chemical, and the last face on the head I got to was the one with 'SCM' and 'TERSA' engraved on the face, and some other writing I couldn't make out clearly. After a few minutes of cleaning, sure enough the writing came into clear view. It was starkly clear. It told me that it was 'verboten' to remove the fixing screws! Shit.

Intentions... well, the road to hell is paved with good ones it seems. I thought I was being careful and meticulous and making reasonable moves in an effort to have the planer head in good function. Now I am worried I have done something I shouldn't have and that leads me to feel less than brilliant.

I'm trying to think of why it would be against the 'Tersa law' to remove those screws. The cap screws in the cutterhead were put in with some sort of thread locking compound and maybe the warning about removing them concerns possible breakage of the bolts, or perhaps the company was worried that the bolts would get reinstalled and not torqued properly, or that the thread-locker wouldn't be renewed. You certainly wouldn't want that part to come loose while the head was spinning or carnage would result. The bolts hold down a bar which serves as the mounting for the Tersa knife. I gather that this is an older form of Tersa as the newer ones, including the one on my Martin, do not have this bar at all - the head is machined in one piece and only the floating wedge bars are placed in the head afterward.

I'm thinking that if any debris gets under that bar and then it was fixed down again, the precise tolerance of the knife position might be affected. In fact, my suspicion is that the precise positioning of that knife support bar is the reason you should never remove the bolts. If the bar is fastened back down and is off by a few thousandths each way with each knife, then potentially the perfect cutting circle is ruined or the knives wont be properly tensioned by the floating wedge bars when the head is spun up. Either way, cut quality would be impaired. I'm hoping my conclusion here is erroneous and all will be okay, but that sinking feeling is definitely present.

The thing is, given the stickiness of the knife removal, and the rust, I wonder if the functioning of the head would have been correct even if I'd left it entirely alone?

Of course, these kind of things invariably happen, Murphy's Law and all, when it is late on Friday or early on Saturday and there is no opportunity to contact technical support personnel until Monday - and this coming Monday is a holiday in the US. I'll have to sit tight for a while and stew on things.

I'm thinking that the 'best case' outcome here is that I have to remove the cutterhead from the planer, remove a spring clip and washer on the end of the cutterhead, which will hopefully allow the wedge bars and blade-support bar to be removed, then I can meticulously clean everything and reassemble, torquing to spec. and threadlocking it out to a fare thee well. Then I put the head back in the machine, and see how it planes. If it doesn't plane as it should, then the cutterhead comes out again, and well, likely I would then be looking at the 'worst case' scenario: I have ruined the cutterhead and will have to obtain a new one, which is an expensive proposition. Neither best nor worst case scenario is especially appetizing.

Yesterday was a great day, today - not so much. I really hope I haven't learned an expensive lesson here. I don't mind the lesson, it's the expense. We'll see what comes out of this. I researched the matter on the web but could find nothing helpful, so Monday (or Tuesday) should provide clarity when I talk to SCM.

All for now, over and out. On to post 3

Friday, February 15, 2013

Moving Along a New Plane of Reality

Today's post is all about transcendence, though concerned merely with aspects of physical reality not spiritual. Best I can do at the moment I'm afraid. That said, my spirits are definitely on the buoyant side, as a new capacity has materialized in my woodworking shop.

Regular readers may recall my luck in acquiring a new jointer late last year. I was absolutely delighted to have scratched that item off the shopping list, and it 'only' took three rounds of buy and sell - first I had a Felder 12", then an antique Oliver 16", and then finally the Martin.

The Martin has been associated closely, and rather uniquely, with a blue planer, though not quite what the folks at Martin would normally advocate as an ideal pairing:


It's comical really, kinda like Laurel and Hardy, however recent projects haven't required any heavy duty stock removal or large pieces of material, so I have been making do quite well with the Makita shoebox. It does struggle on bubinga and similar hard woods once you get wider than about 3", and it does snipe a bit. Better - far better - than nothing though!!

I bought that little gipper thinking that when the time came to get a bigger planer the Makita would be great for taking to the jobsite, which is, after all, what they are made for. The writing was on the wall once I was able to set my shop up with a dust collection system, as that put me at last in a position to get a decent planer. You can run some machines without dust collection and get away with it, but the planer is not one of them. They make a lot of chips in a hurry ans spew them everywhere.

What is 'decent' as far as a planer goes, you might ask? Well, I'm sure there are different ideas out there as to what constitutes a great planer, but for me it would have to be a machine that was adequately sized and powered - a machine that would allow for decently wide material to pass - at least 20" (520mm) - and would accept a stick at least 10" deep as well. These were the first items on the old wish list. A 24" (610mm) planer would be preferable to a 20", but a 20" would certainly do for a while. I was resistant to another 'stepping stone' purchase, but having a choice in the matter might not be possible really given the severity of the increases in the steps of price and my budgetary constraints. The problem with the stepping stone idea, as far as the current woodworking machine market goes, is that re-selling a machine, if you hope to not lose any money at it, can take months and months.

The list of machines that conform to this basic set of wants was already getting quite thinned out, but added to my wish list was: a minimum of 9 horsepower, powered raise and lower of the table, adjustable feed speed, a Tersa 4-knife head, and, if at all possible, doubled rubber outfeed rollers for improved stock handling. I wanted a table that was carried on 4 jack screws, in preference to tables carried on only 2 screws, or on a central hydraulic cylinder or other system. The four screws give the best support in my estimation. A digital readout and 2-speed raise/lower would be very nice to have, but not essential.

Those requirements dropped the list of candidates down to 4 or 5 makes of machines really, and most of those come from Germany. The top of the list was a Martin T45, however at $24,000 or so, and up, depending upon options, it really wasn't looking in the cards, at least not for 2013. Used Martin planers seem a bit scarce on the market at this time. So, scratch that idea, and put into the maybe some day category, you know, after the yacht :^)

A new SCM planer would be another nice possibility, however there we're looking at something like $18,000, which is also well beyond my budget. Hofmann makes a well-built but rather ugly looking machine, to my eyes at least, however a moot point as those machines are as rare as rocking horse poop in North America.

Actually, my budget wasn't all that grand at all and I was intent on saving and saving, making do with what I had as best as I could, farming out any planing work which exceeded the shoebox's capacity, and begging/borrowing time on other people's equipment if I had to. With that plan in play, at the same time I have been keeping my eyes on the used machine market looking for the right machine to come along.

And it did come along, a lot earlier than I had been planning. Not especially convenient, but I found a way to make a deal work, taking on a small amount of debt which I expect to pay off in the next 2 months.

This new (to me) gem arrived today on a truck:


My first impression: it's BIG! I was stunned at how massive this thing is, and it weighs around 2000lbs.

I really lucked out in terms of meeting my wish list. This planer accepts material up to 24.8" (630 mm) wide and 11.8" (300mm) deep, has a 10 horsepower main drive, a second motor providing powered raising and lowering of the table, and a digital readout.

Further, this planer has Tersa head with 4 knives, and dual outfeed rollers, which are pneumatically pressurized and the pressure is adjustable using a dial on the front of the machine:


As you can see, one screw removes a heavy steel (or is it cast iron?) guard over the Tersa head. To the right and left of my hand, and across the other side, are the pneumatic cylinders for pressurizing the infeed and outfeed rollers.

The cutterhead is oxidized and coated with resin, and looks worse in this picture than it actually is:


It should clean up well with some turpentine.

In case you were wondering what exactly I have stumbled into, this planer was made by SCM in 1998, and was used in a one-man shop for about 5 years, so it is really in excellent condition:


The picture really doesn't convey how monstrous this machine is - the raised lid clears the top of my head by at least 12".

The original owner apparently went out of business a few years back, and then took employment in a large millwork shop in Ohio. That same shop bought much of his old equipment at auction, including this planer. However, the large millwork shop already had a 32" planer and a 2-side monster planer, so the 24" SCM was surplus to their needs. I acquired it for $4950, which is about $3000~4000 less than what I might have expected for a machine in this condition and as it is optioned. And having spent time in a one-man shop, for about 5 years or so, the amount of wear and tear is truly minimal.

I gather that SCM has rearranged their line-up of planers and now you can only get the the big motor (9Kw) motor in their top of the line L'Invincibile model - and same for the adjustable pneumatic outfeed rollers. This S-630 model, which they still make, was a well-optioned machine when new, and I've gotta say pretty much ticks every box on my wish list, which means I am no longer going to be shopping for, or dreaming about, any other planer. This is IT!

Here's a look at the controls:


Upper left is the two-speed raise/lower, the black switch giving fast movement and the red button incremental adjustments. The right hand upper corner has the variable feed speed dial.

The digital readout for cutting depth:


At the back of the machine is a secondary emergency stop, and an adjustable dial and manometer for the roller pressure setting:


A look underneath at the four lead screws for raising the table, and the lever for raising and lowering the bed rollers:


One of the boots is shot - from the machines I've seen it would appear to be a common thing for the boots to crack and segment. Replacement would be a hassle of course.

The machine came with a plastic service case, a bunch of wrenches, an original brochure, a factory service and parts manual, along with electrical diagrams:


The shipping from Ohio to my shop ended up costing only $350 or so, which was a great freight rate. I recommend freightcom to anybody - ask for Andrew Vindatello. And no, that was not a paid endorsement - they've been great to me over the past couple of years whenever I have needed anything shipped, so I felt it time to make mention.

So, the machine is not without a few added complications. For starters, the machine's main motor is currently wired for 3-phase 460 volts, which is more than double the voltage I have on tap at the shop. I have been hoping that I could resolve this voltage issue without having to spend too much money, and was relieved when I saw the machine today: the build plate indicates that the machine was originally configured for 230 volt service. At worst, I had thought I might have to buy a step-up transformer, however after talking with SCM in Georgia today it seems like I can simply do some re-wiring and it will run on 230. I might have to swap out an overload protector on them main motor, but maybe not.

The pneumatic outfeed rollers are a cool feature, however that means I need an air compressor, a piece of equipment my shop lacks. The planer has a safety switch which will turn the machine off, and not allow it to be started, unless there is adequate air pressure to the rollers, so this option is not an option, if you know what I mean. The roller's air cylinders don't consume an appreciable amount of air, so I fortunately can get away with a very small compressor. I had hoped I could use an old dental air compressor kicking about the shop, but that turned out to be a 230v single phase model, which would have meant  more wiring hassles. After doing some shopping around, I chose a 1hp. GMC Syclone 1610A Ultra Quiet, Oil-Free Air Compressor, which is shipped for free and cost about $215:


This GMC is not associated to the automaker. This machine runs at only 60 decibels which is around the volume of a normal conversation, and it has an aluminum tank which won't ever rust out. It's an exact clone of the California Air Tools model, but a few dollars cheaper. A one year warranty, and the pump is supposed to last 3000 hours, so it should do for a good while at least. I like how quiet it is:



Given the very low air use by the planer, it shouldn't need to cycle on and off very often, which will extend its lifespan. I can use it with an air nozzle to periodically clean the machine off as well.

I still have to get the S-630 planer down off the pallet and tucked in there next to the jointer, and complete the wiring, air compressor hook up and dust collection hook up work. I'll post pics when it is all tidied up and working. I'm really elated to at last have a planer that will facilitate my work process and improve outcomes. I can put all but one board in my shop through this machine, which is a huge improvement over where I was yesterday. Shopping for a planer is done, as far as I'm concerned. Yay!

Thanks for coming by the Carpentry Way. On to post 2

Tuesday, February 12, 2013

French Connection 11

A received a question recently concerning the applicability of this three legged bench - did people make these? Well, yes - here's at least one, a scale model:


This three-legged bench is really a convenient vehicle for the study of placing an inclined saltaire cross between a cross-beam and purlins, along the lines of this study:


In the last post, it appeared I had completed the drawing work on side 2, the second set of saltaire braces, a pair which have their front and rear sides plumb. Well, not so fast there young fella! While working to develop the brace's joinery details, certain things came to light in regards to the joint where the two pieces cross one another, and that caused a back step in the process.

The first set of braces, on side 1, I had made as square sections, 1.125" on each side. As one might expect, those braces, as they have faces flush to one another, fit together seamlessly when they are the same size each. When it came to side 2, I followed along with that pattern, making the braces 1.125" on each dimension. It makes sense to use the same section of material for all the braces, or so I thought. What happens though, when you use the same size section for each brace on side 2, is that the crossing point between them ends up with some goofy little joint interfaces. This is something I hadn't noticed on the previous drawing go-round (three years back) on this piece.

I'll show you what I mean, using my prior drawing for the trépied établi:


Now, zooming in on the front of the crossing, and looking at the lower intersection, you can see that they don't quite meet spot-on, which leaves a slight little barbe ("beard") indicated by the arrow:


Rotating around the connection, a similar situation occurs at the upper rear intersection, though here the barbe is very slight:


In order to eliminate those barbes, I had to reconsider the dimensions of the sticks. After some thought, I decided to make the plumb measure of the braces equal to the section height of the tripod top beam pieces, at 1.5":


With this change, which was easily accomplished in a 2D to 3D development, the front face's barbe disappears:



Not all was well however at the back - there was still a tiny barbe:


This barbe is a compound joinery effect, as the two sticks each have a different slope. The only way to eliminate this tiny barbe, besides ignoring it of course, leaving a less-than-crisp or fudged fit, would be to change one or both sticks in their section thickness. I decided to change one stick, which made it 1.128" instead of 1.125":


None of these issues revolving around the fit of these parts as the intersection was apparent from the text, and it was difficult to know exactly what was intended, as the drawing of the tripod bench in perspective does not show the meeting points for this side. So, all i can do is discover the issues and try and find the best solutions I can. I'm grateful for the 3D as otherwise I don't think I would have been able to discover these issues so readily from the 2D plans. Indeed, I imagine that the second tiny barbe, as shown a couple of pics above, would have appeared in 2D layout as a tolerance error (it's about pencil line thickness) and I would have just connected the lines - fudged it - and the result would have been a gap in the fit or a not-quite fit.

Anyway, these barbe'd comments, ahem!, are but a warm-up for bigger fish to fry in this project. By far a bigger concern to me is how I am going to put the bits together with joinery.

Here's a look at the older sketch of this project, where you can see the prints (outlines) of a post and two braces (one from side 1 and the other from side 2) as they converge at the top surface of the beam:


Clearly, there is too much going on in that space. While a tenon from brace set 1 (to the right) emerges into clear territory on the top surface of the beam, such is not the case for the brace coming from the left side, from pair 2, which largely occludes with the traced outline for the post.

Here's a view of the same thing from my current drawing, in which I've drawn the post's tenon and the beam mortise already, and you can see where the brace traces emerge on the beam's upper surface:


I can't see any way I can put a through tenon in there coming from the brace - and the text indicates no tenon there, however whether the text shows a joint or not, I have a hard time taking the text seriously. After what happened with the 4-legged Mazerolle tréteau project from a couple of years back, where several mortise and tenon connections were indicated which later proved to be impossible to assemble, call me a skeptic. All tenon depictions in these books I take with a large grain of salt. In this instance, I agree though that no conventional through tenon seem possible in that location.

Take a look at this picture from Delataille's work, which shows a through mortise and tenon connection for the brace:


I'm doubtful that will go together as illustrated, unless some of that new rubberized wood is involved, and that is even presuming that the crossing point of the two braces is formed not from a lap but from three pieces, mortise and tenoned.

Examples of impossible connections abound in Delataille - here are a couple more:



From the maquettes I have seen, these sort of multi-legged saltaire-braced tables invariably have nailed connections. The French aren't that preoccupied with joinery. In some models you can often spot the odd place where a nail has rusted off and some little portion of a brace has fallen off at some past point in time.

Examples:


I don't see any pegs or other joinery telltales.


Here you can see the nailing fairly clearly:


Can't forget this one, one of my favorite little pieces of insanity:


Every time I see it I laugh and wonder how many hours that took to make!

I guess I would rather avoid using nailed or glued connections on this piece, but am seriously doubting how I might realize that goal. It might be unachievable.

Thanks for the visit, and we'll see you next time.