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Hi all,

Now that my thickness sander is about done, I need to start thinking about a go-bar clamping deck and rods etc.

I need to know some of the practical aspects. While I have seen a number of photos, it is difficult to get a sense of the size range for both the deck and the height. Also, I see that some use fiberglass rods others wooden rods (hickory?) and now I read about a spring loaded version. I can see the advantage of the spring-loaded version (no spring fatigue) but I still have no idea how force each rod needs to develop, 5 lbs, 10 lbs, more?

Can someone give me direction in this area? I looked in the jigs section and did a search and while I found some related information, I was unable to get some of the practical questions answered. Oh and if there is anything I am forgetting, please let me know, I can use all the help I can get!

Thanks, Steve Brown

I'm by no means an expert on the matter and I'm sure others with more experience than I will chime in, but a go-bar deck has probably been the easiest (and most helpful) jig I've built so far. I just used double stacked 3/4" MDF for the top and bottom and 1/2" threaded rod 36" long for the posts. Then you can use nuts to set the height of the deck up to 36". I have mine set at around 30". I use just regular poplar and oak dowels 5/16" in diameter I believe. I just cut the dowels at around 1" to 1 1/2" longer than the height of the deck and that seems to give ample clamping pressure. I read not long ago that increasing the flex of the bars doesn't actually add very much pressure, just increases the chances of them breaking, if you're using wooden dowels.
Hope this helps.

Here is a simple gobar deck behind the guy in the orange shirt. 5/16 hardwood dowels from Walmart or lumber yard. The top is adjustable via four bolts. The ripped two by four uprights are two by two's with holes drilled every inch. The bolts are three/eight's by about five inches, no washers or nuts, not needed.

This system allows for quick adjustment and I've felt I'd eventually build a better one, but that was 1999 and this is 2005 and I'm still using it.

I sometimes join tops and backs in it, I brace tops and backs in it with the concave dish in place. I also glue up backs to sides and then finally tops to the sides in the same tool. Of course I have to change from 25 foot dish to 15 foot dish when I proceed.

The upper deck has three holes drilled at about an inch apart too, seems to give all the adjustment a guy could want. The rods flex and stay overnight, you'd think they'd break or wear out from use, but they keep on working.

Thanks guys! You allayed some fears I had. I tend to overthink and therfore overengineer things. I think what you said will get me started. I can always experiment with the actual bars at a later date. If one thing doesn't work, I can try another.

BTW, the hint about the 5/16" dowel really helps. Apparently, the force must be on the order of 1-2 lbs per bar (dowel).

Thanks!

Apparently, the force must be on the order of 1-2 lbs per bar (dowel).

We just went over all this on the MIMF. My go bars measured out at just under 15 pounds pressure each. Another test(simple bathroom scale) with 4 bars came out at just under 60 pounds, backing up my initial findings perfectly.

Don't underestimate the power of a couple dozen go-bars! That's 300 pounds pressure on a clamped up back, and 450-600 pounds on a fully braced top.

Of course, ya'll knew this already, and this thread is just for conversation's sake, right?

Happy Easter, all!!

I gave up on the wooden dowels long ago. they don't hold up. Fiberglass is the best of that option. Spring loaded ones are good but they are more expensive. You need to find something at about 5-10 lbs. Too much ins't good and too little won't do the job either.
   

Longer go-bars give less pressure for a given diameter, but they have more useful 'throw'. I'm getting about 8# pfor a 5/16" dowel. The force doesn't change much over a fairly long range of displacemnts.

I set up my firs go-bar deck by just screwing a piece of plywood to the ceiling. Since then I've gotten a little more sophisticated, but not a whole lot. I like the long bars myself.

The whole point of go-bars, of course, is that they're cheap and you can use a lot of them. This spreads the force out well over the parts to be clamped. You're much less likely to get a 'starved' joint with these, although there are questions about whether they give adequate pressure in some cases.

The worst thing about them: go-bar explosions. One slips loose, and knocks against the next one, which springs out and whacks a couple more into the air, and so forth. Remember the Disney thing about fision, where they had a room full of mouse traps that each had two ping-pong balls on it? They opened the door, threw in a ball, and had a celluloid blizzard in no time.

I put mine together with 1/4" X 4' long "Snow Plow markers" from Home Depot. Get about 25-30. Same deal as Al, screwed ply to the floor (ceiling) joists. The distance from my bech to ceiling is just about right. I think I may have put a 3/4" chunk of MDF under my radius form to bring it up a bit, but those long ones have a nice throw. And I dont have to disassemble a "deck" either. Just stash the rods. Go simple, it's really not a big deal

I'm using 5mm fibreglass rods. If you can't find 'em at home depot, take a look at a kite supply place. They also sell little vinyl caps you can 'finish' the rods off with, which keeps everything in place nicely. The vinyl can discolour the wood, though, so keep that in mind. Not an issue for me because I glue down braces oversize, then trim them, and there's always a caul when I use them to glue down the back. You want at least 35-40 if you're using 'em to glue down your back and top.

My 'Deck' is my heavy MDF desk (weighed down by a computer monitor, a stereo, a TV and various other things which, in addition to the 10 ton MDF, keep things in check), and 'distance' is about 29" from bottom to floor. It's not ideal, but it does the trick. Go-bars are fantastic, wouldn't want to be without them!

Oh, you know how guitars are thick at one end and thinner at the other. I tilt my upper deck the same amount. On the occasion I need a bit more pressure, I have small pieces of brace stock to insert under the gobar stick to get enough pressure.

Mario and Alan, thanks for sharing the Pounds Per Stick, I had no idea it was pressing that hard. It will dent spruce when gluing, but usually it is all sanded out or trimmed away by the time you are done.

Anyway you do it that works is good in my book. If you find a way that works, why change unless you find something better.....?

I make mine from various hardwoods: Oak, Ash, Walnut, Hickory and Cherry. 5/8" - 3/4" wide x 3/16" - 1/4" thick x ? length needed. I have four lengths. One length for gluing back and top braces, one length for the X cap, one length for the upperbout area and one length for the lower bout area when gluing tops and backs on rimsets.

The Oak and Walnut ones exert the most force while the Hickory and Ash the least. I would advise against using Cherry as they tend to break.

_________________
tim...
http://www.mcknightguitars.com

If anyone took the Borges shop tour last year (or saw the ASIA 2003 presentation), here is a system that will look familiar.



Spring-loaded go-bars with wooden wedges to provide the adjustable pressure, and to compensate for different length bars. The wedges work nicely for dowels, etc.

The springs provide downward pressure with MUCH less potential for "go-bar domino" mishaps. A slip will still put a nice ding in a top.

Good to see that Rube Goldberg is alive and well. (An edit here to add that this was not directed at anyone, just a general comment on human nature to make the simple inordinately complex!).

Consider building the deck with 28" between top and bottom; this way you can clamp everything you'll likely need, including bodies, with 24" go-bars. To clamp thin plates, I shove enough scrap 2x4s and 1x2s under my dishes to provide good force.

For go-bars, 3/16" fiberglass provides appropriate force and is almost unbreakable. Once you try these you'll likely be done with wood bars. Plus, they cost less that $1 each if you buy them here:

Fiberglass rods Bob Steidl38439.4106944444

Steve I am at present building a new larger deck for my shop. This one will have an adjustable top to facilitate using the deck for may clamping tasks, from gluing braces to gluing on tops and backs to the rim, without the need of shorter go-bars. The top will adjust by means of wedge-pins above and below the top plate. I will add the drawing s to the OLF library as soon as they are complete. I also think I will be mounting a Lazy Susan turn table with a locking pin as well. Dims will be 30wide x 24deep. The bottom and top are ?” Baltic Birch ply the stand off legs will be oak 2x2x36 with through mortises in three different height locations and ?” oak hammer wedges used to pin the top in position

Oy! Instead of Rube Glodberg-ing the deck, just make the deck one size, and solid, then make some "boxes" to slip under your work for the various height needs. Just like Bob said.

I'll admist to having two different length bars, but I also have slabs of particle board nearby that I can stack to make up anything in between.

Much simpler, and it is important to make your deck solid.

I use hardwood sticks for go-bars. I just rip whatever scraps are handy on the old table saw. I have hundreds of go bars, so even at $1/piece, it would add up if I had to buy them. My deck is 8 feet long, so I can glue up to 4 items at the same time. It doesn't need to be that big, but it is just basicly a strong couter-top bench with a strong "hood". It can also be used as a regular bench. By cantilervering the 'hood', I don't have any uprights in the way as I work, which always bugged me in my first go-bar deck.

Long bars and the ceiling also work <g>

Keep it simple!

Trust me this will be solid. I have used boxes but with my bench height it is just a bit awkward. I work one guitar at a time in the construction process so I don’t mind moving the top. I also have many different length rods right now but I want to stream line the shop a bit. Hence the new deck and some other changes in my work space.

Bob, I'm still trying to figure out how a stick, a spring and a wedge could be considered "inordinately complex"?

I threw that picture out there because I've found it far easier to get consistent results than any of the "sprung stick" methods. I can move a bit faster and get better results - important with hot hide glue. At this point I'm experimenting with vacuum clamping to satisfy my curiosity.

It's just another technique to consider - I'm not claiming it's the best.

Steve,

We were composing at the same time earlier, so I did not see your post until after I posted mine. When I read it, I was concerned that you would think my post was in response to yours, which it was not. So I went back and added the "edit" that I did.

I took your post in the spirit you intended. I just need to refrain from kidding, it's just too easy for all of us to misconstrue.

Bob

Never use the wood one's, but may try that. I have those dumb little 24" round fiberglass rods and talk about if one comes off the brace and takes all the rest like a perfect strike in bowling, get some. I have also tried the rectangle ones like from stew mac. More expense, yes, less hassle than the little round one's, absolutly. I don't care if the little caps are on, which they are like socks in the laundry and just disappear, they suck. I heard could go to Loews or Home Depot and get fence tension ones just the right size. Not in Oklahoma. They must use different fencing here. If anyone has a place to get them and cut them, I for one would buy them by the 2 dozen. I am about out of the little round ones as they break in time, but won't invest in anymore and will try wood first. If not find some here, going to Stew Mac and spend my wood money on some of the rectangle ones, Just my $.02 here

Here's my approach:

First, get 3/16" fiberglass rods --- cheap --- from McMaster-Carr. Part number 8543K59. You get a 5' length for $2.25, which is enough to cut 2 rods from if you have a go-bar deck that is about 2-1/2' high. You can cut them with a hacksaw without too much difficulty.

Second, also from McMaster-Carr, get these rubber end caps, which fit nicely on the ends of the bars: 6448K45. You get 50 caps for $7.88. The rubber caps mean that the bars won't scratch up your work. Also, if you don't put the end caps on, the fibers can sometimes split off the end of the bars and stick into your fingertips in a less than pleasant way. No big deal, but completely unnecessary since the caps are cheap enough.

(Very similar to Bob's setup.)

Cheers,
Kelby.Kelby38439.5735763889

[QUOTE=stan thomison] I don't care if the little caps are on, which they are like socks in the laundry and just disappear, they suck. [/QUOTE]

Superglue them on, and they won't run off on you. Never had bars close to breaking yet, and I'm careful about placing them. Bars don't need a lot of flex to exert plenty of force.

you will care when one slips and gouges a top..Don't ask how I know

That's right, not a lot of flex needed at all. I have hardwood dowels and like the three feet or 36 inch length, all the same. I feel the extra length, makes them more stable in the form. Mine have always been three feet, so I probably am repeating hearsay from someone who's tried several lengths.

One thing is the 5 1/6 inch hardwood dowels from Alco, lumber yards, home improvement centers, are really cheap, 48 to 54 cents each three feet. I've had to glue some little slices of dowel on a few to get them all to a perfect 36 inches, but it's no big deal.

There is a slight variance in the wood dowel, some are a bit stronger that others, which is to be expected. Fiberglass might be better for that very reason. And the Kite link above has a sensible price for them.

I wonder what size would equate with 5/16 wood in strength? 3/16 seems small, maybe a 1/4 inch? Of course these might require the little rubber tips for sure. The wood dowels are fine without them.

Bruce I am using 3/16" fiberglass rods and they have all the force I need. I tried 1/4" but they were too stiff for my taste.. I have a set of 24 with felt bottom furniture pads on the bottom for gluing on tops and backs to the rim. I wood dowls for a long time and switch to fiberglass rods a bit at a time. Just for the life of the rod and lack of memory.

3/16" sounds about right. I'm using 5mm rods, and they work just great. 1/4" = 6.3mm, FYI.

I've got different length rods, one set for bracing, one set for backs/tops, although I actually end up usign all of them, crazy amounts of flex and all when gluing top and back. I'll be getting myself an additional 2-3 dozen bars very soon. This pic shows way, way, way more flex than necessary, and it is risking a 'blow out', but it worked for two guitars. The bars inside the guitar, applying pressure to the under fingerboard headblock 'tounge' are what I consider a 'normal' amount of bend. Want to avoid the risks, though, ergo the getting more bars

Mattia Valente38439.6600694444