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I was watching a Romanillos video a while back and noticed he was using a cool go-bar rod that was not a bent rod, but a spring-loaded device....
It appeared to be a 20" x 3/4" piece of PVC, with a 5/8" wooden dowel, sharpened to a 3/8" point with a cork tip (like a pool queue)
I like this idea as it gives you straight down clamping force.
Inside the PVC rod I imagine a 8" x 5/8" compression spring giving +/- 10lbs compression at 4" deflection.

However, I have been unable to find such a spring -a local shop would make them up for $20/ea....uh......nope.....

Any ideas where I might find a common spring for such an application?

Thanks!!!!!!

Rob

The springs in my set up are 2.5 " long by 3/8 th's - wire being 1.25 mm gauge. Rods are a hardwood dowell at 20" long. The rods do flex a little but not significantly - they certainly work for me.
The springs were obtained from a specialist engineering suppliers - probably not much use to you as I'm UK based. Nowhere near $20 each.

Rob-
McMasterCarr is one place to look- they have all kinds of springs (plus millions of other items).
Make sure you specify that you are a 'business' when dealing with them from Canada (unless they've changed their policies in the past couple of years).

As you probably know, the force 'exerted' by a compression spring is not constant (Hooke's Law?), but depends on the amount of compression. One of the appeals of go-bars is that the force is more-or-less constant after slight deflection.
But those vertical spring-loaded bars do look appealing.

Cheers
John

Check out Waddy's tutorial on how to make the spring loaded go-bar
http://luthiersforum.com/forum/viewtopic.php?f=10117&t=15834

Maybe you can check out those motorbike repair shops, I manage to find some 2nd hand parts springs at a motorbike repair shop.
It's really cheap costing abt 50 cts per piece for a size of 80 mm long with 10mm diameter.

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Sen CL Goh
http://senguitar.blogspot.com

You might check MSC also. I was just looking last week for smaller springs to make the same thing for inside the box. They have several pages of springs to sort through.

Tim

When you make spring loaded bars, you do have to pay attention to the sweet range of the spring that suits the pressure you are looking for. I found that in the case of the spring I used, it worked best at about 3/4 compression, and without changing the height of my go bar deck, but using an insert in the end of my rods, I can get a pressure range in the 7 - 9 lb area for gluing braces and the same for gluing backs with the inserts removed. You could do the same by changing the height of the deck, or using a raised base when gluing braces. But, since my go-bar deck is attached to the solera, when I need it, I just keep it the same all the time. It's simpler, to me.

Gluing braces, with inserts:


Gluing back, without inserts:

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Waddy

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