MDF Okay for Zero Clearance Insert?

[Steve H Graham]

I had half-inch MDF lying around, and the insert in my Powermatic 66 was too worn to meet up with the surface of the table, so I decided to make a new insert. For a person like me, new to woodworking tools, this was actually exciting. I was able to cut the MDF to length and width pretty much instantly, using the table saw. Then I traced the insert's outline on it and cut it out on my new old bandsaw. After that, it was too thick, so I resawed it on the bandsaw. If that sounds dull, imagine trying to do it with an average guy's tools, which consist of a circular saw and a couple of screwdrivers.

Anyway, I had a Microjig splitter lying around, and I decided to install it. Then I noticed the instructions said the insert had to be stiff to work. I put the new insert in the table and pushed on it, and I was able to get it to bend.

I have a big pile of softwood scrap, which is worth its weight in gold. I grabbed a piece and Titebonded it to the bottom of the insert. I didn't use screws because I figured they wouldn't hold well in MDF, and I didn't want the heads poking through the top of the MDF, if I drove them through it and into the scrap. The insert should be rigid now.

Question: is this a stupid idea? I would like to get rid of my scrap MDF, and this looks like a good chance, but I can always drive to the store and see if they have phenolic.

[Randy Rose]

I If that sounds dull, imagine trying to do it with an average guy's tools, which consist of a circular saw and a couple of screwdrivers.

Why does a guy with only a circular saw need a zero clearance insert ?
:) Sorry, couldn`t resist

[Steve H Graham]

Let's not wander off into zen.

[Tony Bilello]

Here is some stuff I did once before on here.
http://sawmillcreek.org/showthread.php?t=103348

[Steve H Graham]

That's pretty cool. I didn't know it was okay to cut formica with a bandsaw.

[Tony Bilello]

I cut the formica with the table saw into rectangles. Then I glued them onto the already shaped MDF and used a flush trimmer bit on my router to finish them off. I never tried cutting formica on a band saw but I see absolutely no reason that you couldnt.

[Peter Quinn]

MDF is great for a ZCI, I use them all the time. I have some 8-32 cap head screws and an 8-32 tap that I use to put leveling screws in and one fresh Lee Valley phenolic ZCI insert that I use as a template to flush trim batches of these MDF inserts as needed. Not sure I trust MDF to hold a splitter when push comes to shove turns into a kick back? I use a biesmeyer splitter on mine and use the band saw to kerf out the back of the insert to allow for the splitter. Reminds me, I need to make another batch soon. I usually make 5 blanks at a time to have for different dado setups or angles, or just to refresh as they get worn out.

[Steve H Graham]

RE the flush router bit, I should have read your doc attachment before I posted.

RE the splitter screws holding in the MDF, it's something I should have considered. Maybe there is a way to use bolts and nuts.

I've been looking at the Shark Guard. I don't think I want to wait 3 months. Maybe I can fabricate something similar.

[Greg Hines, MD]

I did not have any trouble with MDF for zero clearance inserts, or using a MicroJig in them.

Doc

[Craig Johnson]

I had mine originally made with plywood but, its seems all of the plywood that makes it into my garage has to either be warped or become warped before I use it.
MY ZCIs I made were all off just enough to annoy me.
I bought some 1/2" MDF and made 6 new ZCIs.
Works good and dead flat.
Probably will use only that from now on.

[Thomas Williams]

I have used MDF for inserts for years without few problems. I used the MicroJig splitter in the MDF with no problems. As far as the MicroJig splitter holding in the MDF, I slid my fence into my splitter and the MDF did not give, or course my splitter did.

[Myk Rian]

I prefer baltic ply. It holds leveling screws better.

[Bill Huber]

Here is a link to a thread awhile back on ZCI, really good info.

http://www.sawmillcreek.org/showthread.php?t=101164

[Rob Young]

MDF works great for a ZCI. The MDF will take wax just fine and can be made very slick.

One other materials I've heard is nice but never tried is pre-finished wood flooring.

[Myk Rian]

Bill;
I noticed in that thread, talk about the ZCI opening up over time.
I saw an article/tip about using epoxy to fill in the slot, then running the blade back through it to re-cut the slot. Seems like a good idea to keep a ZCI in use.

[Bill Huber]

Bill;
I noticed in that thread, talk about the ZCI opening up over time.
I saw an article/tip about using epoxy to fill in the slot, then running the blade back through it to re-cut the slot. Seems like a good idea to keep a ZCI in use.


People talk about them opening up, I had a Phenolic on my old saw for a year and it was still singing when I sold it, it had not opened up at all.

I have a ZCI for thin and one for normal kerk and just have not had a problem with the Phenolic ones opening up.

With that said, that is a really good idea on fixing one that does open up and I bet that would work very well.

[Gary Lange]

I just bought two Zero Clearance inserts from Peachtree Woodworking and I couldn't have made a better purchase. They are solid as a chunk of steel and fit perfectly when delivered. The price wasn't bad either as they were about $7.00 less then Grizzly and the Grizzly you have to fit yourself.

http://www.ptreeusa.com/zero_clearance.htm

[Robbie Wigginton]

What is the best way to make an insert if the one that came on my saw is only 1/16th of an inch thick?

[Myk Rian]

What is the best way to make an insert if the one that came on my saw is only 1/16th of an inch thick?
If it is aluminum you could make a new one and cut the slot with the blade running up into it. I would use an old blade though. Probably be better to use a jigsaw though.
What saw do you have? Can you post a picture of it?

[Tony Bilello]

What is the best way to make an insert if the one that came on my saw is only 1/16th of an inch thick?


What saw do you have?

[Bill Huber]

What is the best way to make an insert if the one that came on my saw is only 1/16th of an inch thick?


That was the same problem I had with my old Craftsman, it was so thin.

But I found that phenolic worked just fine.

I used the ones from Rockler and just made them like you would any other insert.
http://www.rockler.com/product.cfm?page=17508&filter=table%20saw%20insert

[Robbie Wigginton]

I have a Delta TS350. I was using my dado set recently and had to remove the insert completely to make a cut....probably not the safest method. I thought about using the overlay method but not sure what to do when I need to use the miter gauge.

[Myk Rian]

I had to use my RT to get some extra stock from the edges. Made a rabbet where needed so it would fit flush.

[Stephen Edwards]

Here is some stuff I did once before on here.
http://sawmillcreek.org/showthread.php?t=103348

Thanks Tony. Currently, I'm in the process of tuning my Ridgid contractor's saw. I've been wanting to make some ZCIs myself. Your post with pics is just the kick in the butt that I needed to make them. Thanks again!

[Bill Huber]

I just bought two Zero Clearance inserts from Peachtree Woodworking and I couldn't have made a better purchase. They are solid as a chunk of steel and fit perfectly when delivered. The price wasn't bad either as they were about $7.00 less then Grizzly and the Grizzly you have to fit yourself.

http://www.ptreeusa.com/zero_clearance.htm

Good luck with those, I got 2 of them and both of them sagged in the center after awhile. The sagging in the center caused the front and back ends to come up and would catch the wood as I went to cut it.
It may have just bee the heat here in Texas but I know I will never use them again.

[paul dyar]

I have oak in mine, has worked fine for the 4 years or so.

paul