Laminated handle material warped

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Hey guys,

I glued up some handle material with G10 liners about a month ago at most. They're stabilized cottonwood from Craig Stevens. Since then they warped a bit, enough to grind and fix, but then you might see the line between the liner and wood actually be curved.

Are there are methods to straighten it out a little bit?

It might have been the weather change in the past few weeks - went from dry 80's to humid/wet 50's.

Thanks!
 
Grind off the G10 and re laminate with thicker G10 pressed together with flat plates
 
I've heard that it takes a bit for the stabilized blocks to fully Stabilize once they are finished and cured. How soon after getting them did you use them?
 
I've heard that it takes a bit for the stabilized blocks to fully Stabilize once they are finished and cured. How soon after getting them did you use them?

I had them for a few months before gluing the G10, but I'm not sure how long they've been stabilized before that. They didn't move that much until recently. Kind of a bummer since I already drilled them with holes for hidden pins too.
 
Don, even though many folks think that stabilizing give you plastic-like wood, it surely does not. I have had wood move one me in the manner that you've described from EVERY U.S stabilizing service out there. Granted, in all cases, it was due to wood species and grain/cut direction. You should be able to clamp your scales between two pieces of steel and pop them in for 30 minutes at 190-200 degrees fahrenheit and they "should," go back to straight. Once you pull them out, let them cool to room temperature between the plates.

I hope this helps. It sure is aggravating to have this happen at any stage of production.
 
I've heard that it takes a bit for the stabilized blocks to fully Stabilize once they are finished and cured. How soon after getting them did you use them?
It is usually the oily woods that will bleed or take some time degassing after stabilizing. Cottonwood is usually ready to use right away.
The best advice I can give for future scales came from Mark Knapp.
Store the scales on edge instead of laying flat. If left flat they can cup upwards.
and....
When you are going to laminate g10 to wood try not to let a lot of time pass before adhering to the knife tang.
The g10 and wood react differently to the climate changes, hence the movement.
 
As well, some suggestions here indicate that you can straighten with heat.
If that is true, then so is the opposite!
Heat will warp as well as straighten.
Some of the best advice I ever got was to NEVER!! generate heat in natural handle material.
I used the same 36 grit belt to rough shape my handle material and used that one and ONLY!! belt from late 2007 to early 2013. Over 5 years.
And that's the only belt I ever used.
And I am a full time maker.
I finally replaced it this Spring because I thought the splicing tape was going to wear through.
Point is, I shape may handles with files. Not sanding belts.
The handle material never gets hot.
They also never move.
 
stabilized woods have polymer forced into them. but...they are still wood. wood fibers take in and expel moisture depending on humidity. if a scale is backed with say g-10 you have sealed that side of the scale. if the other side takes in moisture on a humid day it will swell and bow the scale. "end grain woods more so". useing a natural material takes a bit of skill, and if we all had our wish those materials would work easy, stay dead flat and never move. a lot of good posts here. but lets start at the beginning.... woods should be aged years to allow them to find their happy place. then after stabilization they should be rested as well. (why? poylmers shink.) so allowing a block of stabilized wood to shrink and ajust is a good idea. after it has, slice off the first 1/8 inch or so (always wants to warp to the inside) then cut your scales. (what every you do to one side, you must do to the other.) sand, flip,sand turn 180 degrees sand, flip sand flip. stand on their edge. (why? you want both sides of the scales to breath equal and ajust. both sides will both cool and take in what every humidity is in your area on a given day. (on that note, when buying scales,when you get them, stand them on their edge and let them ajust for a couple days.) make sure they no longer want to move. "ALWAYS" sand the back flat on a dead flat surface before atempting to glue them on a knife. the most common mistake knife makers do is when they grind and work the steel and handle material. they heat it with agressive grinding. ( there is no need for this) cutting your material to closer tolarence is a much better way to go. keeping things a bit cooler when shaping drasticly cuts down on woods movements later. also by coating your scales and or sealing them with a finish you cut down on the woods ability to take in moisture or swell. this too can cut down on wood wanting to move. just my opinion but i hope it helps some of you.
 
Don, I'm not sure what tell you about your current dilema, but I have a trick I've learned on my own to prevent that problem. Most guys (that I've seen) will cut their block into scales and then epoxy on the liners. I DO NOT cut my block of wood into scales. I sand the outside faces flat with 80 grit Rhynowet Redline paper on my surface plate. I then scuff the liners on one side with the same 80 grit paper. I then epoxy the liners to the outside faces of my UNCUT block. At this point, I can leave the block, with liners, sitting until I need it. When I'm ready to use it, I split the block down the middle on my band saw and roll the pieces over just like you would when trying to bookmatch. A light scuff with 80 grit to the liners and they're pretty much ready to go. I won't cut the block unless I know I will be able to do a glue up that day. It helps to prevent warpage because the 1" block with liners doesn't move like scales with liners will. Especially if there will be any length of time pass before attaching to the knife.
 
Steevin, PLEASE stop pulling up old threads and resurrecting them. All three of your posts have been on old threads. Do not do it any more. Consider this a polite warning.
The Moderator

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