11 replies to this topic

[cyclingneko]

What are the pro's and con's for plywood/MDF use in jig making. A few things to consider would be; ease to build, price, availability, durability, would one build a more precise jig? What do you use for your jig making needs, use the poll to vote but please also add your comments.

[Jason]

I really don't mdf for anything. Maybe it is good for a bench top skin. Mdf dust really sucks to deal with and the stuff isn't really durable. I like plywood to make jigs and sleds because it is durable. I think that beaver puke (chip board) would be better than mdf.

[Chet]

I have to agree with Jason. Although, I've used MDF for several things. It is generally very flat and very stable. (But don't get it wet, it becomes just the opposite in a hurry.) In my humble opinion if you want a long lasting jig that can be used time and time again, you can't beat phenolic coated plywood. I especially like it in black... which in truth is much harder to work with than a lighter color, but it looks cool when you are done.

[Beechwood Chip]

MDF: doesn't warp, expand, or contract
Plywood: durable, holds screws, doesn't expand or contract, but can warp

[The Wood Servant]

I have clicked Ply because it is my much preferred material for jigs but, I have used 18mm MDF for an awful lot of jigs as well, particularly when making follower jigs for the spindle moulder as I find there is less chance of snagging which does sometimes occur when inner laminates of ply splinter off or as so often happens when you slice into your nice clean sheet you discover gaps and materials used for filling that are not apparent until you make the cut. Also as almost everything I do is a one off the jig is usually short lived and discarded after the piece is made.

[Brian Glendenning]

I vaguely recall that there's a trick to make the edges of MDF hard (e.g., so a pattern will last longer). Does anyone recall what it is?

Cheers,
Brian

[konkers]

You could try wicking some thin CA glue into the edge. I've never tried that with mdf but used to do it all the time with the ends on cardboard and phenolic tubes when building rockets.

[Beechwood Chip]

You could try wicking some thin CA glue into the edge.

I was thinking the same thing, but with thin epoxy.

[LoneRider]

I picked "Whatever I have in the shop", it is not a set rule. Depends what I have that is close to the size, except where I am looking for specific properties. For following jigs on the router table, always MDF. Generally if it requires clamping pressure, or weight, plywood.

[Chet]

I vaguely recall that there's a trick to make the edges of MDF hard (e.g., so a pattern will last longer). Does anyone recall what it is?

Cheers,
Brian

I "paint" mdf all the time with a mixture one half titebond and one half water. It makes it super-smooth and almost as good as a thermofoil finish. One tip, make sure you don't use the water-proof titebond. That won't work, it won't mix well with the water.

[The Wood Servant]

I "paint" mdf all the time with a mixture one half titebond and one half water. It makes it super-smooth and almost as good as a thermofoil finish. One tip, make sure you don't use the water-proof titebond. That won't work, it won't mix well with the water.

Great tip thanks

Pete

[RedOak]

I use both MDF and plywood and sometimes melamine coated particle board shelving. It depends on the use. Plywood is expensive especially quality Baltic birch, but it has the best screw holding ability and most durable. On the other hand MDF is cheap and it is really flat and stable and has good vibration absorption, it is my first choice for router tables and work tables, etc. I also like 1/4" MDF for router bases. I recently made a taper cutting jig from melamine shelving, it was super cheap and entirely adequate and the melamine surface slides really nicely on the table saw. This is not a jig I need very often so I didn't feel that making it from more costly baltic birch would be justified.