Friday, September 18, 2015

Making New Arrangements (II)

Both machines, the 1970's vintage Zimmermann pattern maker's milling machine and the Wadkin Dimension saw, are currently at sea, and they are scheduled to arrive in Boston by the end of the month. In the interim, I've continued to chip away at various tasks to get my shop ready.

I've installed most of the electrical service for the two machines. I am not a certified electrician,  just someone who has done some wiring over the years, however I had a licensed electrician come by and take a look at my work and he gave me the the thumbs up.

All the EMT is installed now, coming about 90' from the load center, though a couple of pull boxes, to the location on the wall where I have decided to place the transformer:


The transformer was hoisted up high and bolted to a couple of 2x4's, which were in turn bolted to the brickwork behind. The incoming power routes down on the left, and travels first to a 'Square D' DU322 Safety Switch:


From the switch, the line travels up to a junction box, where the transition can be made to some 3/4" flexible tubing (a requirement as the transformer vibrates slightly) and connection can then be made to the transformer. I used 'Liquid-Tuff' tubing, and I think it looks a lot cleaner than the metal coil BX cable housing. Easier to cut clean on the ends too.

The switch does not have a provision for the neutral wire, however this is unimportant as the neutral can be run directly through and up to the transformer and is not directly switch controlled. I verified this with the electrician of course.

The transformer is simple to wire, and clearly labeled, almost plug and play. At present I am waiting on the AWG #8 wire which will run from the load center to the transformer (ordered online), however  in the meantime I have been able to install the wire from the transformer's output side on down, as it is 10 gauge, and I could pick the small amount up I needed at a local store. The left side will have the 208v/60 input, while the right side outputs at 456v/60hz. As the output side is somewhat close to the 480v. standard, the 480Y/277 US wiring code convention is followed, which makes the wire colors for the high voltage side Brown-Orange-Yellow, with a grey neutral:


The neutral voltage is the line voltage of 456v, divided by √3, or about 1.73205..., which equals about 263v. Similarly, the neutral voltage for 208v is divided by √3 to give a value of 120v. A lot of people get confused by the fact that the phase voltages in the 208Y/120 system are separately 120v., but the line voltage measured across 2 phases is 208v. - a lot of people think it ought to be 240 volts. It's a vector result (each phase being 120˚ apart), not a simple addition however.

The colors for the 208Y/120 input side are Black-Red-Blue, with the neutral in white. Ground wire is green. The term 'high voltage' is slightly misleading however, as in the big picture, systems carrying 600v or less are classified as 'low voltage' by the utility. Medium voltage are those applications from 601v to 34,500v, and high voltage is 34,500v and up.

The output from the transformer travels down through some more 3/4" flexible tubing to a second junction box where it is attached to a pair of EMT-cased feeds, each going to a separate outlet with receptacle:


When 480v is employed, all the transitions out of the EMT into the junction boxes have to have plastic bushings installed.

The grey neutral wires, as they will not be used by either machine, are simply capped off in the junction boxes. I am putting the neutral in all the way to the end for what might be called 'future considerations'. The handy thing about the 208Y/120v system is that any one of the conductors can be paired with the neutral to provide 120v single phase connection if required.

The machines will be tied to the receptacles with 'twist-lock' plugs as they call them at the electrical supply places (though in fact, these particular ones do not twist to lock but simply insert), and some AWG 10-gauge, 4-wire machine service cable:


I probably could have scaled down to 12 gauge for the cable, however the 10 gauge isn't hurting anything either, except my wallet perhaps. The two metal pieces above in the picture are strain-relief connectors, and these two l'il gippers cost more than the 30' of heavy service cable I purchased anyhow. Most of the wiring parts are not too expensive, and the global cost for copper is down right now so wire is not as expensive as it was last year.

Here I'm wiring up one of the receptacles - starting by trimming the wires to length:


Love the Knipex lineman pliers.

Then on to stripping the housing off the ends. I have come to find these sort of mechanical strippers to be the most comfortable to use:


I could work with these for hours and not get tired and they always give clean cuts:


The receptacle, a Leviton 2730 rated for 3-phase 4-wire 480v service, is attached to the cover plate, and then I connect the ground wire as a next step:


**Of course, always make sure power is disconnected before doing any electrical work. I'm sure I didn't have to state that, but, you never know.... I'm comfortable working with this stuff, but if you're not, by all means have a professional do the work.

The phases are identified on the receptacle as X-Y-Z, and here I'm connecting the brown wire to 'X':


If you look closely under the fastening tab you will see that there is an 'X' cast right into the black plastic.

All done:


Buttoned up:


The plug looks like this:


The terminal with the bent-over tab portion is the ground. When you install a receptacle - and this goes for 115v single phase receptacles as well - the ground terminal should be uppermost. Check back up a couple of pics and you will note that the mounted receptacle has the 'L' shaped terminal at the top.

Oriented this way, if the plug is partially removed from the outlet by accident, and is still electrically live, and a metal object like a bare wire or ruler, etc, happened to fall onto the connection, it will touch the ground prong and not short anything out and start a fire.

The plug separates into two halves:


At the terminal connection end the connections are clearly labeled, just like the receptacle, with 'G' for ground and then X-Y-Z:


I'll leave off wiring those up for the time being.

At the other end of my shop, further developments have ensued with the wood rack, now with a clamp rack on the front:


While it might look like I have now trapped boards within the wood rack, this clamp rack is in fact hinged on one side and can be readily swung out of the way. Also, I have mounted the rack higher than previously, which allows my longest clamps to now be hung up instead of leaned against the wall.

I have realized that I only occasionally need to access the wood rack, so it is no great inconvenience to have the clamps in front like that. Besides, only the middle bay of the wood rack is actually affected, the wood in the side bays can be accessed from their side openings easily.

One more pic for good luck:


I may add another hinged panel above the clamps to store more stuff. Anything to get stuff off the floor and into a place where they can be clearly identified and found when needed. So tired of searching for stuff and scratching my head about where to place things. Slowly getting to a place on my train ride called 'Organized'. Perhaps the next station will be 'Productivity' ? :^)

All for now, I hope you enjoyed the update.

Thursday, September 10, 2015

Making New Arrangements

With a couple of new machines on the way soon, neither of which might be called petite, I've had to reshuffle things in my shop. So, right now, things are a bit chaotic and I'm spending a lot of time on ladders.

I had a vertical wood rack with a footprint of 4'x4' which had to be taken down, reconfigured and set up on the other end of my shop space. It's now a 3-bay affair about 2'x4':


On the left side of the rack you can see some of the figured shedua planking poking up. That material came earlier in the week and absolutely met my expectations. Various woods occupy the middle bay, with bubinga on the right.

The top of the rack is a widened and lengthened deck for storing stuff I don't need too often:


I've taken to storing quite a bit of stuff in my shop on elevated pallets, 8'~10' up on the walls. Anything to get it off the floor and out of the way. I've got a raft of wood to tuck away -  I've resorted to pulling some of it off site altogether.

On the wall where the wood rack used to be I have sheathed the brick with some plywood in preparation for mounting some electrical equipment:


The 3-phase step-up transformer is in the foreground of the above picture. It will be mounted on the wall about 8' up.

After looking at the situation for a while I decided to rearrange the positions of my bandsaw and planer, swapping them on each side of the post:


The change gives me slightly more room to move by on the right side of the planer, compared to the bandsaw table which used to stick out in the same space, and the planer now has 12.5' of space in front of it for feeding stock as compared to 11' in the previous position.

Moving the large bandsaw, I also turned it 90˚ to take advantage of a corridor between the jointer and super surfacer, and that also allowed for a place to tuck in the little Hitachi bandsaw:


The new arrangement requires no changes to the electrical or air systems, however a few more dust collection fittings will be needed to hook up both bandsaws. I'm still trying to figure out where the clamp racks will go!

The large bandsaw table in its new orientation meant I can use the corridors in front and behind the table more effectively for feeding stock:


A view from the corridor between the jointer and super surfacer down to the bandsaw:


I'll be also extending the dust collection piping a good 30' to reach the tablesaw, and this is one of the those costs which always seems to be higher than expected. "It's just a few fittings and a length of pipe or three...", I think to myself. Wrong. In particular the flex hose is a shocking price. The pipe and fittings are ordered from Air Handling Systems down in CT and should be ready for pick up sometime next week.

I just thought I'd share some pics of what is what in my shop at the moment. Should be another day or two and I can get back to working some teak - you can see it stacked up here, there, and everywhere in the above picture.

Thanks for visiting the Carpentry Way. There is a follow up post: Post II

Saturday, September 5, 2015

A Ming-Inspired Cabinet (6)

In the last post in this thread I mentioned that I had obtained some 'Honduran' Mahogany for the secondary wood on the cabinet. It was good quality stuff, but truth be told I wasn't entirely pleased with the material I received. I had wanted quartersawn mahogany, while 7 out of the 10 boards received did not fitting that description even remotely.

I realize now that quartersawn mahogany is not generally what was being cut at the mills- mahogany saw logs are invariably sawn through and through - and thus QS stock is less available than I had thought. Sawing through a log like that, you would likely only obtain a couple of quartersawn boards per log. I felt that trying to obtain more of that material (in bulk) in the hope of scoring some more quartersawn boards was not looking promising. None of the retailers I spoke with seemed even willing to do a sort for a few boards, and fair enough - though none of them seemed too interested when I wanted 150 board feet either.

After further rumination on the matter, I decided it would be best to choose a different species for the secondary wood, a species which was ideally cut for quartersawn from the get-go and which would be a good match for the bubinga used for the rest of the cabinet.

I've already considered woods such as mahogany, black cherry, and Swiss pear wood for the secondary wood. None of those were likely to fit the requirements I had in terms of grain orientation, so I kept looking.

I finally came across a suitable material, and it is botanically related to bubinga (which is guibortia tessmanii OR guibortia pellagriniana OR guibortia demeusei).

This is a wood called Shedua, aka Ovangkol, which comes from the species guibortia ehie. This is a somewhat smaller tree than those species from which bubinga is obtained. The wood comes from West African countries like Gabon and Cameroon, and the tree is more commonly utilized for its gum resin, called Congo copal, than its timber. The timber is not very commonly available, and it does seem to find a certain favor among the guitar-making community from the research I have done. Shedua should be a good match texturally for the bubinga, and that is an important consideration when matching a couple of woods together in a piece.

Here's a guitar with a shedua back:


(From: http://www.guitarbench.com/2012/01/04/shedua-tonewood-profile/)

As you can see, it has a more brownish cast than bubinga, but shares the black streaks. Comparing Shedua's mechanical properties with bubinga, it is very close indeed, being very slightly lighter and less dense, a little lower in volumetric change due to moisture content change, a slight bit softer in terms of crushing strength and a hair stiffer in bending strength (modulus of elasticity). I imagine, therefore, that it should have fairly similar working qualities to bubinga.

This image from Hearne Hardwoods shows the varied appearance of Shedua based on the grain orientation:


As it so happens, Hearne was one of the few places in the US which had any stock of Shedua at all, let alone QS and/or figured stock.

In fact, they had a decently sized stack of 12/4 material, 6~12" wide, 16' long or longer, and some of it was quartersawn. Considering few other retailers have any of this material, it was amazing to come across such nice stock. They also took time to reply to my emails, and send pictures, once I had demonstrated solid interest in the material - - and had given them my credit card info! Hearne seems to be a retailer specializing in high quality and rare woods.

They sent me some pictures of a couple of boards which matched the requirements I gave them, swabbed with alcohol to make the figure a bit clearer though not showing the tone which will be obtained with a proper finish:


They were wondering if I was so determined to have quartersawn because I was a luthier, however I let them know they were guessing wrong. I do have some specific reasons for wanting quartersawn material of course.


The guy who sent me the pictures stated that these two boards might be the nicest in the entire pile.




I asked for a follow-up pic of the end grain of the two boards, to confirm they were what I wanted in terms of grain orientation:


And the other board, about 12" wide:


The sticks are hard to scale until you notice that a forklift is doing the lifting....

The stock looked good to me. The price was steep, at $35/board foot, so each of those boards was $1400.00, however I was able to offset some of the cost somewhat by selling a portion of the previously-acquired mahogany off to another woodworker in my building.

I ordered those two boards and they should be at my shop in another 3~4 days. I think this wood will go very nicely with the bubinga used for the bulk of the cabinet:


I think the CAD representation of the Shedua is approximate at best. Definitely a bit greener than brown, however not a concern at this juncture and easy enough to correct.

In recent days I have revised the horizontal and vertical dividers on the lower bank of drawers, making them straight instead of having them match the drawer curves, and I also recessed them back slightly - this for among other reasons, to increase the shadow interplay between the curved drawers and the surrounding framework:


The divider's outer arrises will additionally be chamfered.

The drawers themselves will have a beaded perimeter detail, and have the drawer sidewall through- tenons poking out, neither of which is illustrated yet, and the handle design for the drawers remains an open question. Likewise, the upper set of drawers and doors remains just a frontal plane at the moment with no allowance for set back, chamfering, etc.. Getting there!

Thanks for visiting the Carpentry Way. Got some machine's coming soon so I am working on getting my shop ready for that - this will likely be the subject of the next post, #7.