What to use for sub-fence for miter saw?

[George Bokros]

What would you use to make a taller fence for your miter saw -

1. Melamine faced particle board? I have some that is not flat, is that a risk in that material?

2. MDF? Would you use unfaced? All I can find is unfaced and I prefer not to go the expense of buying some laminate to add it to the mdf.

3. Baltic birch plywood?

4 Phenolic faced ply from Woodcraft?

Thanks

[Paul K. Johnson]

I like MDF a lot. It's flatter than any plywood I've ever had and can be close to dead flat if you fasten it down properly. I would make it with either replaceable inserts or make it so it could slide so you could get fresh backer material as necessary.

An easy way to make inserts is just dovetail them. Make them about 3" wide with 45 degree bevels and make the fence to match. Then just slide in a new one when you need it. Maybe drill for a small pin to hold it in place if you think it might slide up in use.