Bench Clamps L Clamps Are these for sale?

[Matt Haugen]

I have seen Frank's tutorial on fixing distended sides and I have my own project with these problems. I am looking to buy some of the bench clamps (like the ones Frank made). Does anyone know if these things are for sale somewhere? Below is a link to show what I am referring to. Thanks for any input.

http://www.frets.com/FretsPages/Luthier/Tools/BenchClamps/benchclam...

[Scott Supak]

Don't know of anyone offering these... surprised StewMac hasn't yet ;)

I had a friend at a local machine shop make mine with extra threaded holes for the "pressure bolts(?)" so there's some flexibility when lining things up. I'll use short lengths of dowel rod drilled to slip over the end of the bolts and padded with cork or leather & wax paper on the contact side. You can also adjust the height of the instrument with various padded blocks and the height of the clamps with plywood shims to achieve really accurate application of pressure.

These things work great and attest to the genius of Frank!

[David Farmer]

Here is an alternative I'm currently using.

I have used a classical building solera to mash a Mando back into position. It worked o.k. but after a long time in the jig you could feel the sides were a series of flats even though the cauls were many and very close together. I would try and have the contact points at least approximate the curve. I would also make sure your plates are at a sufficient humidity. You can't compress a ring of wood, (sides) smaller. Your really redistributing the bulge evenly. If the plate is smaller than it was the day it was originally  glued on, the excess length of the side has nowhere to go.

[Ned Knepp]

Before I saw Franks elegant brackets I did a set in wood to fix a mandolin. My jig was several vertical blocks attached to a block which was cut to follow the curve I was working with . The vertical blocks had long screws through them for applying pressure. The whole thing was screwed to a larger jig I made to hold the mandolin immobile. It worked but was pretty clumsy compared to Franks idea.

The one thing I did that was different and that I found essential  was to make a cork lined clamping caul cut about 3/8" thick and fit to the curvature of the top plate. It overlapped the length of the warp but about a half inch on each end and was the full height of the side  This support allowed me to tighten up the screws a turn or so at a time but insured that the curve remained true over it's length. No flat spots. The original gap was huge so I actually used the setup with the periodic application of moisture and heat, to gradually move the side back into place over a couple of days before I glued it up. When I did that I got some help so I could apply the HHG and have the caul ready to go. Two of us managed to glue and clamp in a matter of seconds. The result was dead on.

What I rigged worked OK for that application but Frank's brackets are much more flexible. Next time I'll make some like Frank's.

[onewent]

Matt .. I made a set for myself using Frank's as a model.  I bought the aluminum on ebay, and the bolts at the hardware store.  I cut the aluminum on my band saw (messy), drilled and tapped holes, and put them to use.  Probably 3 or 4 hrs work.  I've never seen them for sale while making my rounds on the net.

Since I work on a lot of old, cheap 'catalog' guitars from the 20s and 30s, I get a lot of milage out of them.  The glue from the large guitar factories just doesn't hold well over time, and a lot of that likely had to do with the treatment/care of the guitar, too ;-)

Tom

[Thomas James]

I bought 4X6" aluminum angle and had it sliced into sections. Worked great. Thanks Frank!

[Ned Knepp]

Thomas, how much do they flex when you tighten things down.?  I had to use a LOT of pressure to get the mandolin side back into place. 

[Thomas James]

They do flex a bit under heavy load. How much? I don't remember - as it was a while back. They got the job done. I did drill some angled holes on a few at the inside corner as per Frank's example.

[Ned Knepp]

As long as the flex is managable. Thanks' Thomas. I may actually go this route in the near future so I have them on hand. I'm sure I'd use them if they were around, I just keep putting off making them.