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gunnarbriem
08-20-2010, 03:05 PM
hey there. im a newbie and about to start my first build. i was thinking about making the sides by laminating some walnut veneer in a mould. you guys got some experiences with such a method? results and/or problems? got some quartersawn walnut veneer that ill glue up a thickness of 2mm.

Pete Howlett
08-20-2010, 10:51 PM
I am very seriously considering this as a method of construction for an electro travel uke I am designing. However, laminating technology is not just simply pressing veneers into a mold. When I made veneered furniture I used the vacuum bag method. I'll be doing this if I go that route. It would be worth you reading up on this if you are not already familiar with the method... At college, guitars were made with laminated sides using male/female molds. With modern day routers they are relatively straightforward to make. I'd use an accurate male mold minus the thickness of the sides plus 1/2mm for aluminium caul strip with the female true, plus 1/2mm for aluminium caul strips and plusanother 2mm for the cork lining I'd use. This part would be split in 3 with the male being left whole and fixed to a base board. Loads of 6" cramps would be reuquired plus a torque wrench to check that the prassure on each clamp was even... See why the bag method is the more favored?

thistle3585
08-21-2010, 05:37 AM
There is a mandolin builder that builds sides in this manner. I'd make the male and female mold then cut the female mold into thirds and hinge the outside "wings". Clamp the middle down then clamp the wings down. I think vacuum bagging would be overkill in this application. The problem will be keeping from gluing the sides and clamp together. You can't use mold release because it would contaminate the surface of the sides and cause problems in finishing. When it comes down to it. I think you're creating more work than if you bent the sides traditionally.

Moore Bettah Ukuleles
08-21-2010, 08:01 AM
But why?.... Learn how to bend, it's pretty easy. You'll thank me the first time you sand through the veneer.

Pete Howlett
08-21-2010, 09:05 AM
I'm making my own .8mm veneers for thisidea...

Timbuck
08-21-2010, 10:05 AM
My first experiment at bending sides was with veneers..I took 3 pieces of standard mahogany veneer (it was all I had at the time, left over from another project)..glued them together with Titebond..and before they completly set... I put them in my new hot Foxy Bender that I'd just completed..it bent easy...the laminations sort of slid into place...after an hour of cooling down I took them out, and they had set solid ..and there was no spring back at all.

I recon if you let the glue set before bending it might give you problems , like creasing at the waist.

gunnarbriem
08-21-2010, 01:21 PM
bending is definately something ill check out later on, but i will first make 1or 2 bodies with laminates. what thickness are the sides supposed to be for bending? i got got some walnut, mahogany and maple scraps from the shop i sanded down to 3mm. thought id use those for top and back.

gunnarbriem
08-21-2010, 01:25 PM
yes pete, ive seen something on that vacuum proccess, looks to be efficient and convenient, but my setup is very primitive at this stage. ive made a mould from plywood and MDF, a male/female thing with the male 2mm offset.
ill have to post some pics.

also, anybody know if Oregon Pine is useable for tops and backs? or instruments at all. got a piece of perfectly quarter-sawn doing nothing.

Pete Howlett
08-21-2010, 01:58 PM
Make sure you split the female mold anmd use a thin metal shim to take out any irregularities...have you also allowed for the glue line? Pesronally if I was using titebond I'd thin it by 5% with water.

Timbuck
08-21-2010, 11:11 PM
I've just watched an episode of "How it's Made" on TV..they were making Grand Piano's....The sides of the piano are made from laminated Maple boards and the laminations were glued and pressed into piano shape in a giant bender while the glue was wet, and left for 24 hours to set.
I've found this old Video of the process..
http://www.youtube.com/watch?v=tEnuMbyw1eE&feature=related
this is the one on TV
http://www.youtube.com/watch?v=qdFejZgOHDA

Moore Bettah Ukuleles
08-22-2010, 06:47 AM
I use a hot pipe to bend my pianos on.

ksquine
08-23-2010, 09:01 AM
If you have the mold already....go ahead and try it. Maybe with some cheap test veneer first
I'm interested to see how it comes out.