So usually when I make a jig for the shop I usually just grab what I have laying around. This time around I need to make a jig for using my router to flatten soom walnut boards. I am planing on using plywood only problem, I need to go buy some. So my question is when your making your jigs what kind of plywood do you use?
Replies
For me, the choice of ply depends on the nature of the jig, how it will be used, and how long I want it to last. I like so-called Baltic Birch (BB) ply (not the "Big Box" stuff) for greater dimensional consistency, and use Phenolic-covered BB where I want the surface to be particularly smooth and slippery. The Phenolic ply requires some care when cutting, however, to avoid chip-out.
JT,
What Ralph said. I like true baltic birch plywood which means: no voids, thin plies, genuine hard birch.
If you can get this, it will make a particularly good template or jig when treated to some fine sanding (especially on the the edges) and a wax polish. The fine quality of those void-free, hard edges means that tempates can be made very accurately, with none of that annoying spelky, holey, soft edge that can spoil a job involving bearings following the edge, as in routing.
Also, double-side tape sticks better to a good BB ply as the face veneers are of good quality and properly stuck to the sheet, no bubbles, unlike some of the cheap stuff.
Lataxe
If the jig/fixture is just locating something (drill press e.g.) then you can get away with ply, plastic, aluminum, and I use a lot of Jatoba. If the substrate receives clamping (toggles, cams, etc) I would not use ply. If accuracy is your goal, all plys will deflect under moderate clamping loads, rock & roll, & mis-locate your work; I wouldn't use it.
A contrarian vote agin' ply.
For temporary jigs/fixtures I use MDF at 1/2 or 3/4 inch depending on the bit depth I will use. And sometimes 1/4 inch 'quality' underlayment plywood.. But it is about $20.00 dollars plus for a 5X5 foot sheet verses $5.00 for the MDF .. Or is that MDF made from Wheat Stalks? Not sure, but it is stable but it will bend a bit if you force it...
I think the 'quality' underlayment ply from a BigBox will work for most projects you need a pattern for.
This forum post is now archived. Commenting has been disabled