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Sorry if this has been asked before. I am looking at getting some fibreglass rods to use for go-bars after having a nightmare doing gluing on parts that clamps won't reach.

I have sourced a supplier who can provide 5 metre length rods they can cut to length. They supply various diameter rods from 2mm to 12mm.

So really what diameter is best & what length? I was thinking 50cm lengths but unsure what diameter would be required.

Thanks.

I use 3/16" (<5mm) at 24" (~60cm). I tried 1/4" (>6mm) and they were just way too stiff, at least at that length.

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Jonathan Kendall, Siloam Springs AR

Save yourself some time and contact John Hall at Blues Creek Guitars. He has pre-made rods ready to use out of the box... I speak from experience when I say that they are great!

Ray

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Guitar Building = Continuous Improvement Process

I use 3/16" (4.8mm) rods cut to 2' (58.8 cm) length. I order them in 4' lengths from Into the Wind kite supply. They also have the little caps to put on them. The rods are easy to cut with a Dremel cutoff wheel. Here's a link:

http://www.intothewind.com/shop/Repair_and_Kitemaking/Fiberglass_Rods_for_kites/3-16_FG_Rod

edit: This helped me remember I wanted to get some more go bars so I ordered enough materials for 20 go bars for $23 plus $8 shipping. Works out to $1.55 each which is pretty reasonable.

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Steve Smith
"Music is what feelings sound like"

Peter-
The length depends, of course,on the height you have available above your work surface.
Within reason, the higher the 'deck' the more adaptable it seems to be. With shorter go-bars - which are stiffer- you will find that a bit of difference in the work height will make your fiberglass rods very awkward to use. The alternatives are to have a 'selection' of rod lengths available, or a system to raise and lower the work (or the upper deck) to keep the amount of 'bend' in the rods about the same.
50 cm is quite short.
If you have room, I'd suggest thinking about making the deck higher.
Another (completely different) system to consider is the spring-loaded unbent 'rods' - I think Waddy Thomson uses these, but I may be wrong on that. They are adaptable for height and seem more stable than 'sprung' bent rods.
(You've probably seen some of my posts about not liking those round FG rods, preferring wood, so I'llnot belabour that idea here.)

Cheers
John

Another source: http://www.goodwinds.com/

I bought the black, long rods (72"), paid extra shipping, and cut to my requirements (dremel with carbide blade is more than adequate). Tape area of cut to minimize any shredding. Order PLENTY of endcaps!!! More than you think you will need. BTW, cutting this stuff creates an awful smell. I would reccomend a mask.

Mike

Thanks for the replies everyone. I wish I was able to contact John Hall but I would have to import it to the UK and after customs and shipping it's pretty expensive unless I make a substantial order to make it worth while

So I should be aiming at about 24"-28" length sticks.

My advice would be to pick up a piece of (1/4"?) wood dowel locally and do some experiments. You will get an idea of how the 'stiffness' changes with length.
My deck uses sticks that are 32"-36" long, and if I were building it again, I'd go 'taller'.
Cheers
John

If you can't find a kite shop that has what you are looking for, try battens from an easily obtained wood. It doesn't have to be quartersawn, but do check for runout. The first one you cut and flex will tell you if its going to work or not. You might have to experiment a bit to get the flex you want.

When you put your deck together, I'd suggest you put some carpeting on the top to keep the rods or battens from slipping and attacking. I never appreciated having to wear glasses until one of my rods slipped and hit me in the face. My glasses saved me from serious eye damaged. The impact tore my glasses off and threw them a couple of feet away.

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Aoibeann

The carpet idea is EXCELLENT!! Now why did I not ever think of that??? Also, DO NOT use MDF for a go-bar deck. Too flexible.

BTW, dowels will work fine, you may break a few, but they are cheap. Another downside is they tend to remain warped after use. Just a little bend will do ya. Anymore and you are just bending the rod. Search the forums for a discussion(s) on the amount of force a go-bar can exert and how more bending provides nothing more than a breaking risk. Fascinating stuff.

Mike

Doesn't HAVE to be carpet even. I used a scrap piece of med weight canvas & it works great.

wood dowels are not very good and will bend and weaken very fast. Find reinforced fiberglass . Kite building shops may have it. I have me extruded here in the states. You need to find something that can give you about an 8 lb push.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Here's another source for fiberglass rods.
Max-Gain Systems Inc. They supply FG rods and tubes for antennas.

http://www.mgs4u.com/fiberglass-tube-rod.htm

René

Anybody care to explain why they are called "go-bars"?