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I have some fibreglass rod ready to make bats and I was going to go for the shelf above the workbench design. Shelf would be about a metre above the bench and then I could raise the height of the disk by putting things between it and the workbench.this sound like a plan? If so, how long should I cut my bars?

Thanks for all the help so far, very grateful.

Make sure the shelf is higher than the top of your head, otherwise you'll be constantly bashing your head into it when placing the braces. I know this from experience. The length of the rods is best done by trial and error. Make sure the shelf is well reinforced it doesn't work well if it flexes.

I've been considering the same thing. I currently have 2 decks set at different heights. One for bracing backs and tops, the other for clamping rims and backs. My glass rods are cut to 24".

Cheers, M

I use 24" bars and have my go-deck height around 30". I use a variety of different platforms from 2"-7" depending on what I am gluing. With this setup I can brace or glue tops and back in the same deck.

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Josh House

Canadian Luthier Supply
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What thickness are your FG rods?

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I've got five rods, 3 meters long, 4mm thick.

thinking 60 cm rods and 80cm for the bench to shelf the then I can build up underneath for bracing and not have them over flexed for gluing on backs and tops etc. Sound like the right ball park?

i use 6 mm fiberglass rods that are about one inch longer than the distance from the part being clamped to the top of the deck.

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member of the guild of professional dilettantes

If the 4mm rods are like the one I bought off ebay intended for roman blinds, 600mm length doesn't really give as much pressure as you want, 4.5 or 5mm is better.
Get a length, hold it at 600mm of it, push down on top of a set of scales.
7/8 pounds is what most people advised as I remember from previous posts IIRC
I got less than half of that.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Well those are the same ones I have but I decided I can just use plenty of them to get increased pressure.seem to be working nicely. Any advice on cutting fibreglass without getting irritating little splinters.Thanks all.

Can't really avoid dust, and it is nasty, especially if you breath it in. Think permanent bleeding/scarred lungs etc..
What I did was to work outside using a hacksaw with a new, fine blade, dust mask, thin leather gloves, safety glasses.
Supported the rod in a "mitre box" type fixture as it was cut.
Sanded the ends to round them to prevent them penetrating the end caps.
Wiped with a damp cloth after (throw away with the gloves).
Had to scrap a couple because the ends split, but wasn't too bad as I now have 80 or 90, albeit a bit short (400 mm gave about 3.1 kg force), but great for putting backs on boxes.
Come to think of it, a wet tile cutter might work well, but I don't have one.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Some time ago, one of the engineering types around here explained that any given rod length and diameter gives the same pressure regardless of deck height. More flex makes it scarier to get all those rods set. I keep a few large scraps of MDF around to shim up things if my rods are a bit short.

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Mike Lindstrom

diamond 4.5in wheel in a angle grinder fb rod in vice for cutting to lengtth

Tape two together??????????

That is not exactly how it works. For a given diameter and length rod, the force will be (close to) the same no mater how much it is flexed, once you deflect past the minimum required amount. That does not mean that length of the bar and deck height are not important. If you increase the deck height requiring longer bars, the amount of force exerted drops off (for a given rod diameter). Think of a section of PVC pipe, it would be very difficult to flex a 2 foot section by pushing on the ends, but a 12 foot section of that same pipe would bend readily.

I have reinforcements on the ceiling above my bench to act as my upper deck. I don't know the height off the top of my head, but it us much more than the typical 24 inches of a moveable go bar deck. To compensate, I use thicker fiberglass rids than what would be used on a shorter deck. It works out great, I don't have to store the gobar deck when not in use, I have plenty of headroom when using it and I can just by the fiberglass driveway marking rods from the home store to use as my bars.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

My deck is infinitely adjustable, I bought eight 3/4" pony (bottom half) clamps and I can raise and lower my deck as needed, I use 3/16 rods 32" long but also have a set of walnut strips for heavy duty clamping

Water is great for containing dust when cutting. Try doing it outside with a hacksaw and garden hose trickling water on it. Maybe take a couple cinder blocks and clamp the rod to them to hold it steady while you saw, instead of holding it with your hand.

Kathy Matsushita has an adjustable height go-bar deck using pipe clamps for adjustment. Check out her website.

Bob

I really like having my bars go to the ceiling.
they have a bigger thickness range, nothing to block the light, and no supports to get in the way.
a little experimentation and you can quickly come up with rip dimensions of straight grained wood that work like a charm.

This has been talked about at pretty great lengths, but I just wanted to add that my go-bar deck is adjustable, as well. I can't even imagine what a pain in the neck it would be to have it at a fixed height and always have to worry about getting the right shims under whatever part was being worked on. I know plenty of guys do it, but the adjustable height works well for me. I use four lengths of all-thread with nuts and washers to hold everything in place. When not in use (often, for me), it breaks down and stores away easily.

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sweat the small stuff.

I made mine using all-thread bar too with the intention of winding the upper deck up and down to get the right height. In the end I found this to be such a faff that it is quicker to slide a block under the dish to raise the height of that instead!

I've seen ClinchRivers go bar deck, and really like the adjustability. Hows it going Greg!? Mine is fixed height and held up by poles on each corner. The poles really get in the way. I will some day soon build an adjustable height deck that hangs from the ceiling. Lets see more pics of adjustable go bar decks!

Haha! That sounds about right. Making large adjustments can be a bit time consuming. It got me thinking and after a little search online, I came across these "slip-on lock nuts."

http://www.fastenal.com/web/products/details/0123070?searchMode=productSearch&filterByVendingMachine=

Anyone have any experience with them? They would make height adjustments much quicker!

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sweat the small stuff.

Just blundering along, my 14 year honors student, freshman soccer, guitar playing, singing, daughter keeps us hopping but its fun.
Here is my go-bar deck, the infinite adjustability really comes in handy. (looks like a bomb went off in the shop )