Wood questions

Matoaka

MGF, Master Grumble Framer
Joined
Apr 28, 2002
Posts
519
Loc
Albuquerque, NM
I usually order moulding in lengths; then store vertically until the art package is completed (which could mean anywhere from 2 to 7 days in storage before I cut and join). Even though I do a cursory check for warpage upon arrival, I sometimes find that the moulding is twisted or dog-legged a bit too much when I cut. Should I be cutting and joining as soon as the moulding arrives?

New Mexico is very dry (except for swampy August). Should I be storing horizontally instead? I have a LOT of stock moulding which came with the shop when we bought it a couple of months ago.

And (last question), is there any way to reverse or correct warpage?

Thanks for any help!
Susan
 
I really don't think a couple of days would cause warpage. However, if you really think it is it would be better to cut and join your frame first.

Long term storage I have had better luck storage horizontally.


For your last question, I have tried and tried in vein for years. I wish I could find a solution.
 
Probably not much can be done about it. The relative scarcity of wood vs. the demand has frame manufacturers using lower quality woods than they have in the past and the wood is not getting cured as well before milling. Warp and wind (twisting) are going to be inherent in dealing with any length moulding.
Your problem may be compounded by the low RH of New Mexico if the moulding is coming from somewhere with a significantly higher RH, but short term vertical or horizontal storage should not have any appreciable effect on the moulding. For long term vertical is considered to be better, but not everyone has 10-12 foot ceilings.
 
We keep our length horizontally, too – we’ve only got 8 foot ceilings.

In New England we have a very dry season in the winter and it can get pretty muggy in the summer. Since most moulding are supposed to be manufactured using kiln dried wood, it’s probably nothing that you are doing or even your environment.

Warping seems to be worse with some manufactures/distributors than with others. L-J is pretty good; Admiral is downright lousy.
 
Cut and join as soon as the moulding arrives or as soon as you can. You have nothing to loose. The moulding will at least be easier to cut; whether or not it'll warp or wind after you cut and join it is problamatic. My experience is it won't. I've even forced warped moulding into a frame and the frame stayed flat.
 
Using mechanical hold-downs when sawing will relieve the twisting as a moulding is sawed. It will then spring back when the clamps are released.

When joining, let each corner dry in the vice (clamp) before going on to the next corner. Slight twisting will be "corrected" in this manner. However, if you break open a glued corner the twist will re-appear.
 
Another trick that helps with twisted moulding is to make sure that you join the Rabbet up end of the twisted leg first - then you are pushing down when joining the final corner. Sometimes you have to carefully sequence the joins in a different order to make this all work - violating the long leg left rule.

Pat :D
 
Thanks for all the information. But Wally raises an interesting question regarding the diminishing wood supply. Is anyone using that plastic moulding... looks like injected foam?? I don't know much about it. Is it worth looking into?
 
Is anyone using that plastic moulding... looks like injected foam?? I don't know much about it. Is it worth looking into?
<center><font face=madrone size=7> NO!</font></center>

That stuff is junk! It is too soft to join properly, and the rails of even an 8 x 10 will bow.

Stay away from it … it is evil!
 
On the other hand, warpage is rarely a problem with the plastic (I forget what the stuff is really called) since you can "bend it, shape it, any way you want it."

Most Grumblers have pretty strong feelings about this stuff. Not me. I'm ambivalent. I bought six profiles years ago, used it up and didn't reorder. Some of it looked pretty good. It took enough extra care to cut and join that I'm not sure the actual savings were all that great, though.

I used to carry a line of plastic ovals. Customers would pick one up and ask me, "Is this wood?" I would usually answer, "If you have to ask, does it matter?"
 
Originally posted by Matoaka:
Is anyone using that plastic moulding... looks like injected foam??...Is it worth looking into?
Of the roughly 2,000 samples on my wall, about a dozen are extruded polystyrene, mixed into the selection by color. Customers choose them by appearance, and the slightly-lower price is a plus.

Obviously, Bill Henry has had some kind of unpleasant experience with plastic mouldings.

I like them. They are easy to handle and store, their finishes are at least as durable as most woods, they don't warp, and there are no knots or grain defects. They cut and join just like wood, except that cyanoacrylate glue is used.

The plastics are more flexible than similar-profile woods, and the overall structural strength is less. But that doesn't mean they're inadequate for most jobs. If you fill your frames when fitting, and attach the back of the moulding to the final filler with polyester tape, they are quite sturdy.

We've used them on a limited basis for about 8 years, and have never had trouble with them. The plastics are much better than a few years ago, and continuing to improve. One of these days, we will be using more plastic mouldings than wood.
 
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