zero clearance troat plate

[Jwelch]

I am looking for the best material to make a zero clearance throat plate for my craftsman table saw. It is a very old table saw and I can't find any information on available blanks to buy. I have created a few out of 1/4 inch hardwood board but the problem I am having is the humidity in southeast Texas causes them to warp. So I was wondering if there was any material that might hold up better to the climate in my area?

[Bill Holt]

First, welcome to the forum, this is a great place to hang out.  Most of mine are phanalic (I think that is what it's called).  I see a lot made of plywood.

[Phil S.]

I made mine out of Corian scraps I got for free from a sink and counter shop.  I used the metal insert that came with the saw as a template and a trim bit in my router to cut them to shape after they were first roughed out.  The Corian was a bit too thick so I cut a rebate around the perimeter.  Drilled and tapped 4 holes spaced around the rim and turned in some set screws to level up the plate.  Only down side is that the Corian is somewhat brittle and will break if you pound on it. DAMHIKT 
  But Corian glues well.
  Been working well for me for years.

[dg152]

I think the word Bill is looking for is "phenolic". It's a hard, slick plastic that might work for you. Like you, I had a Craftsman table saw but I can't remember the thickness of the insert. Measure the needed thickness then go to Walmart or Target and take a look at their plastic cutting boards. Usually that material is pretty tough and slick and may work for you. There are numerous after market inserts on-line, as well.

[fredhargis]

I think Bill meant phenolic, and if you can find some it would be excellent (if I misspoke Bill, I apologize). But Phi's answer might be a little easier. Use 1/2" plywood or MDF, and route an edge in it to sit flush with the saw table. That might also be a porblem getting you blade low enough to cut a slot...put a 7 1/4" circ saw blade in it and cut an opening to allow you to go back to the 10" blade and finish it up (or you could use your dado set to cut it).

[®smpr_fi_mac®]

I build mine from 3/4" Baltic birch plywood and drill recesses with a forstner bit where it sits on the mounts on the saw top.

I drill them so it sits about 1/16" below the surface of the saw. Then I drill and tap holes at each mount for set screws and level it with the surface with them.

I also do what Fred suggests to get the slot cut the first time--mount a circular saw blade or a dado blade.

[measure once cut remeasure]

I do a combination of both Phil and Brad.

1/2" thick solid surface materail (unknown brand) free scrap material. My Table saw has tabs on the bottom inside of the throat plate that hold the plate. The factory throat plate uses set scres to adjust the height. I also use a forstner bit on the bootom side to thin the the material where the tabs are. I drill and tap the counter top material to use set screws for leveling.

A big benefit of the solid surface material is the weight. If i was to use a lightweight material, the suction from an overhead dust collection shroud with a 4" port might lift it.
I use the same material for a zero clearance fence on my miter saw.

[jteneyck]

I do a combination of both Phil and Brad.

1/2" thick solid surface materail (unknown brand) free scrap material.  My Table saw has tabs on the bottom inside of the throat plate that hold the plate.  The factory throat plate uses set scres to adjust the height.  I also use a forstner bit on the bootom side to thin the the material where the tabs are.  I drill and tap the counter top material to use set screws for leveling.

A big benefit of the solid surface material is the weight. If i was to use a lightweight material, the suction from an overhead dust collection shroud with a 4" port might lift it.
I use the same material for a zero clearance fence on my miter saw.

It's not a good idea to just rely on the mass of the ZCI to hold it in place, although I know many are made that way.  My old Sears TS has a metal tab at the back that fits under the CI top and a countersunk screw at the front.  There's no way it can come out.  When I built some new ZCI's for it I replicated those features in the 1/2" BB I used.  With my Unisaw I added a metal clip at the back to replicate at least half the features of the Sears saw.  

ZCI's wear out right where the blade enters it while the bulk of the part is still good, so I fashioned one for my Unisaw with a dovetailed replaceable insert.  The insert is made of hardwood and is easily replaced w/o having to fashion a new plate.  

John

[brianwelch]

Good source for inserts is MLCS woodworking, free shipping and reasonable pricing.

https://www.mlcswoodworking.com/shopsite...+table+saw

scroll down about 1/2 way...

[Jwelch]

Thank you everyone for your input on this. I will take your advice and see what I can figure out for my saw. I will upload some pictures when I get things worked out. The biggest problem I have is I don't have a router so cutting thicker lumber to fit the table saw is a lot harder to do without that so I was trying to stay close to the thickness of the insert that it came with.