Zero clearance insert problem

[Scott Schwake]

I bought this from Rockler, but it doesn't fit. According to their website, it's laminated phenolic resin. I just need to shave a bit off the bottom, can I do this with a router?

[Tom Henderson2]

If it is phenolic you should be able to machine the phenolic without any difficulty.

-TH

[glenn bradley]

Phenolic machines well. If you do get any esidue build up on your cutters, clean it off right away. It is much easier than trying to do it afer a few days. Are you talking about thinning it around the edges or overall?

[Bruce Page]

If you only have a little to take off it might be better to use a file or some emery paper taped down to a flat surface.
It’s always easier to remove material than to put it back on. DAMHIKT

[Chris Padilla]

Normal ww'ing tools will handle the insert no problem. About how much needs removed and from where? Did you buy the wrong insert and just want to "make it work" or what? Most inserts have a couple of "fit bumps" that need to be gently sanded/filed down to get a nice tight fit since even the exact same table top of the exact same table saw can vary just a tad from machine to machine.

You could always double-stick tape your oiriginal insert to the Rockler one and using a flush trim bit on a router table, shave it down but I'd leave it just a hair bigger so you can get a snug fit.

[Scott Schwake]

Are you talking about thinning it around the edges or overall?


About how much needs removed and from where? Did you buy the wrong insert and just want to "make it work" or what?

I don't need to thin the edges, I just need to remove some of the material on the bottom of the insert, essentially make the lip wider in the "corners" to fit into the opening in my tablesaw. It's the right insert, when I flip it upside down it fits in the opening, but when I set it in the opening the correct way, it sits proud of the table top. It looks like I need to remove about 5/16" of the thickness of the plate in the corners to make it work.

[Chris Padilla]

Ah, I see now! Pictures really help explain things!

I think I would put the insert into the opening, put something heavy on top of it, and then see if you can reach INTO your saw and draw the outline of the throat onto the ZCI so you know where to remove material. I have no clue if this is posslble or not. Another idea would be to put chalk all over the opening and then carefully PRESS the insert into it to leave an impression.

As to chopping out the extra material, a router is likely to be ideal but you'll need to put in some support around the insert to give the router a firm base to lay on.

Overall, it appears to me that you need to look at a different brand of ZCI or simply make your own. This all appears to be a real hassle to go through to get it working. Once you own a ZCI, you'll want to have one for different blades and possibly even for different angles of cuts.

[Norman Pyles]

I'm confused as to why it would fit upside down, and not the right way. Are the leveling screws sitting flush with the bottom?

[Rick Levine]

Scott,

Go to your dentist's office and ask them for some of the carbon type of paper they use to check the fit of a crown. Place the paper between the insert and the saw, press down and it will leave a mark to indicate the material you need to remove.

[glenn bradley]

Chris has got it. Just rabbet that stuff out of the way. If you have a small router like a Colt or laminate trimmer you could almost sneak up on it free hand. The large oval shape will keep it positioned so the lower shape doesn't have to fit like a glove.

[Chuck Tringo]

Heres how I would do it, I learned it for templating bead board panels over electrical outlets from a andyman magazine I believe....borrow some lipstick from you wife/GF/daughter/etc. and put it on the 'lips' that you know are interfering with the ZCI fitting in the throat; place the ZCI in the throat right side up as it would sit while using it; press down; pull it out and you now have a lipstick outline of the area you need to remove. :p Use files, handsaws, or whatever esle you think would work of to remove this material.

[Scott Schwake]

Thanks for the replies everyone, I got this finished up tonight. I used my router table & straight bit to mill out the excess, worked great. I definitely need to learn to make my own, can't be that hard.

BTW, the blade seems to rub against the side of the insert after cutting the kerf, is that normal?

[glenn bradley]

BTW, the blade seems to rub against the side of the insert after cutting the kerf, is that normal?

Hmmm, the teeth should be wider than the blank. If the blade is at 90* when raised and the ZCI is well seated, it should not rub. As far as making them yourself, you are correct; it isn't that bad. Now that you've got a feel for them, you can see what they're about. I generally make a half dozen or so at a time as the setup takes longer than the making.

[Tom Veatch]

...
BTW, the blade seems to rub against the side of the insert after cutting the kerf, is that normal?

If by blade, you mean the blade disk, no, that's not normal. If you mean the teeth of the blade, yes, that is normal until the insert has been used enough for blade deflections to wear some clearance in the "zero" clearance insert.

[Wayne Cannon]

Lipstick works very well in place of carbon paper (stains wood, though)! I have yet to find a woman without a number of lipsticks that they don't really like, but aren't ready to throw away. I keep a lipstick in my pencil-marker-chalk drawer.

[Rick Thom]

If by blade, you mean the blade disk, no, that's not normal. If you mean the teeth of the blade, yes, that is normal until the insert has been used enough for blade deflections to wear some clearance in the "zero" clearance insert.
If you change your bevel on the saw, and then return it to the original angle used to make the initial cut in the throat plate, if it isn't PRECISELY the same angle, then of course the blade will take off a bit of extra material from where it contacts the plate. Again, this in itself is normal.
As others have said, you will likely end up with an array of different throat plates, maybe some full kerf, some thin kerf if you use both types of blades, dados of varying widths, a number of different bevels. It's quite important to have a fairly close fit between the blade and throat plate to avoid tear-out. So, I suggest you learn to make your own throat plates if you want to save some $. Rather than go through the methodology here, do a search on the forum and you will find instructions and examples.

[Jeff Nicol]

Good morning! I have used phenolic and other types of material in the plastic media. When you run the blade up through it heat is generated and it melts a bit and expands. A few times up and down will stop the rubbing. Also the blade may not be at perfect 90 degrees so when you start the cut it is over to the right a bit and when you stop the blade and run it up and down not running it would rub. It looks like you have the same saw as I do so I hope this helps. I make mine out of plexi or some out of baltic birch plywood.

Good luck!

Jeff

[Scott Schwake]

It looks like you have the same saw as I do so I hope this helps. I make mine out of plexi or some out of baltic birch plywood.

Good luck!

Jeff

I was thinking about making some out of plywood. The insert has to be about 3/16" thick at the edges to sit flush with the table top, any problems with the insert flexing with such a thin lip?

[glenn bradley]

I was thinking about making some out of plywood. The insert has to be about 3/16" thick at the edges to sit flush with the table top, any problems with the insert flexing with such a thin lip?

Sounds like an older Craftsman/Emerson saw. I had one and used 1/4" masonite that I put a 1/16" rabbet around the outer edge. I also ran a piece of oak as a rib about dead center, front to back. This cleared the arbor and nut and added stiffness. The outer edge was too thin to use any type of leveling screw but it is important to replicate the retaining screw slot or any pins that keep the plate in. I just used layers of tape for leveling if required.