Official Luthiers Forum!

Did a bunch of shopping over the weekend - sharpening supplies @ Highland Hardware & go-bar deck components @ the Despot - and made strides clearing out my soon-to-be-workshop. In the process I've developed some questions.

Specifics are about go-bar construction & compromising on materials: can one mix MDF and plywood in top & base? can one substitute 3/4" conduit for the 1"? And how to get around the lack of tee-nuts & aluminum washers? I figure any washer's better than no washer, & the tee-nuts can be replaced w/ recessed hex nuts, but I have little experience w/ substitutions like this & would love to hear opinions before I proceed.

More general questions are about the workspace itself: I'm a fairly tall guy (~6' 2") w/ some back problems, so the last thing I want is to build a mess o' benches & find they're too short (or too tall) to actually work at. I know kitchen counters usually run around 30", and I often get pains from working on surfaces that low. Any words of wisdom from the tall crowd here?

I'll have to save the other questions for now (being as I'm at work).

I have a 42" bench that I use for assembly. It is about the right height for me (I am also 6'2"). But I have a larger work bench that is at a more standard height.

The assembly bench is ~32" x 40" Just big enough to work on a guitar.


Some tasks (such as glue up) seem to work better on the assembly bench, and others (like sanding a rim) seem to work better for me at the shorter bench.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Kitchen counters are usually 36".

Two sheet of 5/8" ply or mdf laminated togetherfor the bottom, recess and epoxy in 3/8" hex nuts in to the bottom laminate. 3/8" all-thread posts instead of 1/2", 3/8" plain washers nuts and 1/2" sch 80 pvc pipe for the scratch guard on the all-thread.

Keep in mind that all you are doing here is building two parallel surfaces one for the part to set on and one to wedge the rods against. There are a ton of different ways to do this. I have used the floor, long Hickory rods and 3/4" ply fastened to the ceiling

I'm 6'5. My back is fine but it's a constant struggle to get my workspaces high enough, largly because my father and brother are only 6' and everyone else in the shop is 5'6-5'10... The most comfortable workspaces for me are the highest ;) I find around elbow height is the most comfortable and for extended periods of sitting a tall stool is way better than a chair. The stool also lets you use workspaces your comfortable standing at.

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CVT Inc.
A tour of our shop (Somewhat outdated)
My Personal eBay profile. BCWoodBug

I have standard height workbenches, but I made one about 40" high for the go bar deck to sit on. I'm 6'2" also. It works well for me. Actually, I assemble all over the place. Including my regular bench, and my table saw top.

My go bar deck is made of three layers on the base, 2 mdf and one 3/4" plywood sandwiched between them. The top is 2 layers of 3/4 plywood. I used 3/8" all thread and 3/4" conduit. Regular flat washers and regular hex nuts countersunk. Its very sturdy (overkill) but I like it and it works great. The top is about 24" from the base and I use 24" fiberglass go bars. They don't have to bend much to exert full pressure. I use 3/16 rods. I have some 1/4" rods, too, but they are tooooo strong for a spruce top, 3/16" is perfect. I also left my all thread about 10" long above the top of the deck in case I need more room. Fiberglass rods can be bought very cheap at "intothewind.com". If you get more than 11, they are $1.25 each and are 48" long. I bought 20 and cut them in half. That works great for clamping braces. When I clamped the top and back onto the sides, I left the guitar in the mold, so I made about 30 shorter rods for that.



BTW, I also sunk my conduit about 1/2" into top and bottom.

Ronold man38656.5825578704

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

Ron--What are you using for dowels? I'm starting to break my 5/16" wood dowels and need to replace them.
Sorry for breaking into your thread here, Charlie.
Thanks
Nelson

Nelson, I'm using 3/16" fiberglass rods. Nearly unbreakable, very consistent pressure (about 8 pounds per rod) and cheap. Order from "intothewind.com", they are a kite making outfit. Order 12 or more and the rods are $1.25 each and they are 48" long. Cut them in half and that's dirt cheap. Also get enough end caps for all the rods you're going to make.


fiberglass go bars here

Ronold man38656.611724537

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

Charlie,

Here's the trick on bench height. The best height for a bench depends on what you will use it for. How's that for a cop-out answer? Well, to avoid completely copping out, here's some specifics.

Generally, lower benches are better for physical tasks like handplaning because you can put your weight into your work. Higher benches are better for detail work because you can see what you are doing better.   Imagine how far down you would want your work to be if you were hammering a nail into a board, or shaping a neck with a rasp, then imagine how much closer to your chest/face you would want your work to be if you were screwing in a very tiny screw (such as when installing tuning machines) or soldering a pick-up.

So, before you determine your bench height, make sure to ask yourself what all you plan to use it for. If it's mostly for making guitars, you would probably want it a bit higher than if you were going to be doing much cabinet-making.

A fairly standard bench height is tall enough that, when you stand straight with your arms at your sides, you can rest the palm of your hands on the top without having to bend your arms much. However, if you are mostly going to be making guitars, and you aren't planning to do much handtool work, you may want to go with the belt-buckle test --- the top of the bench is as high as the middle of your belt buckle. This should make the bench a couple inches higher than the palm-of-the-hand method. (I'm assuming you aren't yet old enough to wear your pants pulled up to your armpits or young enough to wear them halfway to your knees.)

If you have enough space to have multiple benches, you may want to build one assembly bench a few inches higher.

As for the go-bar deck, the details aren't important. The basic design is simply a piece of wood on the top, a piece of wood on the bottom, and any hardware that will keep them roughly the same distance apart. It doesn't much matter whether you use plywood, MDF, or whatever. It doesn't much matter whether you are using aluminum washers, stainless steel, or what. You can use steel conduit or PVC. Wing nuts or hex nuts. It all works the same.

U sed MDF on my go bar deck orriginally and found it didn't hold up well and also that the MDF was hard for the Bars to grip on at the top.

Good deal on the fiber-rods Ron, THANKS

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Anderson Guitars
Clearwater,Fl. 33755

When I built my go-bar deck several years ago, i built everything too light. My first 20' arch top turned out to be about 13' when I pulled it out of the deck. The dish AND the top & bottom MDF plates on the deck were all noticeably distorted. After that experience, I got really silly & my "opus two" dishes weigh about 20 pounds each. (Stressed skin construction, 3 layers of 3/4" MDF) Solid as a rock, but don't drop one on your toes!!!
Somewhere in the middle, I'm sure there is an ideal.
To fix the deck, I screwed & glued stiffener strips to the upper & lower surface.
Dan'l Daniel M38656.7361226852

A note on the fiberglas rods: the price in quantity is now $1.35 each; still,
not much considering each is effectively 2 - and thanks so much for the
heads-up, Ron!

(Into the Wind is a fun place to visit if you're ever in Boulder, BTW - it's on
the Pearl Street Mall, east of Broadway.)

Thanks for all the go-bar input, gents!

I was pretty sure that my substitutions were reasonable, but ya never
know.... Looks like it will turn out to be 2 slabs of 1/2" MDF between 2
slabs of 3/4" plywood on the bottom (2-1/2" thick), and 1 slab of 1/2"
plywood on top of 2 slabs of 1/2" MDF (1-1/2" thick), washers on both
sides of each slab, & lockwashers on top & underneath.

I got Titebond brown to glue up the slabs - comments or suggestions?

And do y'all finish your slabs, or leave 'em raw?chmood38656.7646412037

Charlie, what are you using to make your dish? If your dish is solid (i.e., thick enough not to bend under the pressure of the go-bars), I think all that material on the bottom slab of the deck is overkill.

My dish is two slabs of 3/4" MDF, and it doesn't bend at all. My go-bar deck has 1 sheet of 3/4" baltic birch plywood on the bottom, and I have no problems. (The top slab is also 1 piece of 3/4" baltic birch ply.)

The slimmed-down version of the go-bar deck is nice because it's easy store away. Disassembled, it is not very heavy and doesn't take up much room on a top shelf in my shop.

I'm not trying to talk you outof the thicker bottom slab; it certainly won't hurt anything. But IMHO, it's unnecessary.

The shed I'm converting is 11 x 19, or 209 sq.ft, up on blocks & not
weather-tight.

To make it weather-tight, I plan to frame a false-front @ ground level,
which will add the necessary height to permit a real exterior door. To
accomplish this, I figure I'll need to pour some concrete for a (footed?)
pad.

Does this sound extreme? It does to me, but I've been wracking my
brains for years & this is the only plan I've come up with that *can* work -
other than scrapping the shed & starting from scratch (can't afford that) )
This seems like it ought to be one-person doable, but I'd like a reality
check, please! Anyone ever undertake something like this?

Kelby, I was actually planning to buy dishes from Luthier Suppliers. I know I
could make them, but honestly, I just can't see how to do it in my mind, and
that makes me reluctant to try it (maybe once I've actually *seen* one...).

As for overkill on the base, I was going by the StewMac info sheet, which
calls for 4 pieces of 3/4" ply for a 3" thick base & 1-1/2" top.chmood38656.9199768519

Thanks Ron,
I just ordered 30 rods and 60 caps. Should have made that 120 caps. Dang, why do I think of these things after I order. Getting old isn't all it's cracked up to be.

[QUOTE=BlueSpirit]Getting old isn't all it's cracked up to be.[/QUOTE]
Isn't THAT the truth?

Todd, I'm sure you're right: I'm sure that once I have a router & learn how to
use it, I'll have little trouble proceeding; but I'm kinda waiting until I have a
place (shop) to put it in - the mosquitos are still pretty bad 'round here. So
I'll hold off on buying them (I really need to avoid any expenses I can), and
thanks.

Charlie, like Kelby said, my dishes are also two layers of mdf thick. Each side is concave, one for gluing the braces and one for sanding. If you order a dish, I would back it with another piece of mdf or plywood to make sure it can't warp. If you're getting two different rediuses, just glue them back to back.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

That sounds great, Todd - thanks!

On the subject of routers, Cumpiano's book assumes that one has a router,
and I know that routers have become as ubiquitous as table saws, but I've
never had one, never used one, and never seen one in use; this translates
to me being dirt-ignorant on routers.

I know you're a tool guru, Todd, and woodworker extraordinaire: can a
laminate trimmer totally handle all routing tasks a luthier may encounter, or
is the overlap between it & the 'standard' router slim enough to require
both? Whichever one I get, I'm likely to stick with it until either my first
commission or my 60th birthday - not that soon in either event (besides, I
have to buy wood)!

[QUOTE=Brad Goodman] Kitchen counters are usually 36".[/QUOTE]
Right you are, Brad - my bad! I was obviously thinking desktop height.

Still, for a planing surface, I think I'd prefer a couple inches lower - which
falls right in w/ Todd's 34" height & ???'s 'palm-height' estimate; for close
work, assembly, etc. I think I'd prefer closer to 44-45" - belly-button, not
belt-buckle height.

The suggestions & rules-of-thumb you guys (no gals?) have given me are
invaluable - my guesswork feel much more educated now. Thanks again!

Hi,

ToddStock (recently named "Senior Member"), you're probably right about keeping the bit size small for a laminate trimmer but I have a different practical experience.

I've been using a 1/2" diameter mortising bit in a Harbour Freight (cheap & flimsy) laminate trimmer with no problems. I run this in my plate thicknessing jig to get guitar tops, backs, & sides near correct thickness. This use is probably not very taxing on the trimmer motor because only about 1/8" of the lower cutting edges of the bit are being used in this process.

Man, I've been eyeing that Rigid trimmer at Home Deep-hole with an unhealthy tool lust. Who needs a big, heavy router when you can do allof it (or most of it) with a sweet little laminate trimmer.

Skip

Another quick way to attach your router to jigs is to use a template insert. When make the dishes I sell (double laminated MDF) the process I use is as follows:
(my dishes are 24 inch diamtre.

1) Cut mdf to 24.125 square on table saw

2) draw diagonal lines to get centre of board

3) drill 5/16 hole in the cntre of the mdf for pivot of the tremel I use for my router (the tremel is a piece of scrap plywood with a 5/16 inch dowel at one end and then 12.5 inches up I have centred a 1.125 inch hole that template bushing insert fits into and vuala! a tremel!)

4) use the router and a .5 inch solid carbide up-cut spiral bit and serveral passes to cut out perfect cirles (alternately you could cut out the circles on the band saw and trim them with this router system)

5) Using a 5/16 dowel as a centreing guide I glue two pieces of mdf together with eight clamps around the outside edge and AR (yellow) glue.

6) Using a sled just like Todd's but positioned over my rim sander I place the mdf lamintaion on the rim sander and use it to spin the disc as I slower the router down the sled with the smae .5 inch carbide bit. My sled differs from Todd's in that the rails are only 1.125 inches apart and I use the template bushing again the guide.

7) Using 80 and 120 grit papers snad the dish, add two coats of water borne varnishes to seal it (or a sealer of your choice) and you are good to go.

By finding the post I did on building my rim sander and on making sanding dishes you will see my set up also.

Hope this helps!

Shane

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Canada

kinda like my bowl profile fixture in the Library of Plans. I made interchangable guide inserts for each bowl radius I use.

Yes this is a blaten attempt to promote the library of plans

MichaelP38663.5916203704