Zero Clearance Insert Question

Rob Keeble

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GTA Ontario Canada
Okay so I can make a ZCI for my saw, BUT.......that works fine when the blade is at 90 degrees to the table.:)

Can a person make one for say a 22.5 degree cut and then if so how do you do it.:huh::dunno:

I tried a variety of ways and gave up. Tried to use my 8 inch dado blade set to the same angle to cut a wider slot but for reasons that stumped me (i presume having to do with the anles) I could then not use my 10 inch bade in this slot. In the end gave up considered this tooooo dangerous to mess about with. :(

Anyways is it possible?

Thanks
 
hey rob, put in new insert ,,have balde lowered to the max then set angle to where you want it.. clamp insert down and slooowly raise blade up threw it.. this will give you what your after but it wont work for a 90 degree cut just the angle you set your saw at.. then mark the insert for next time..
 
hey rob, put in new insert ,,have balde lowered to the max then set angle to where you want it.. clamp insert down and slooowly raise blade up threw it.. this will give you what your after but it wont work for a 90 degree cut just the angle you set your saw at.. then mark the insert for next time..

I think I tried that once Larry and it didn't work. When you lay the blade over to the angle you want it still comes up in the same plane as if it were at 90* to the table so the blade will try to go through the ZCI with the side of the blade pushing against the ZCI. That's the best I can explain it. Clear as mud??:D
 
I think I tried that once Larry and it didn't work. When you lay the blade over to the angle you want it still comes up in the same plane as if it were at 90* to the table so the blade will try to go through the ZCI with the side of the blade pushing against the ZCI. That's the best I can explain it. Clear as mud??:D

Royall,
I don't understand that at all. What Larry said is exactly how I've made mine. I have one at 22.5°, and another for 45°, and didn't have any problem at all making them.

My saw is a Shop Fox cabinet saw. What's yours?

Does your blade drop down enough to clear the underside of the insert, or does it rub?
 
I have several for frequently used angles. Route a stopped dado to allow for the angled blade position when dropping the insert in. The insert would have to approach at the angle of the blade without the dado. At 90* this is fine but at an angle, unless you saw is a lot different than mine; this ain't gonna happen:

45-under.jpg

Another view:

45-dado.jpg

Cut slot as usual (this ones a bit thrashed, time for another):

45-top.jpg

I do the same for the CMS:

45-others.jpg
 
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Royall,
I don't understand that at all. What Larry said is exactly how I've made mine. I have one at 22.5°, and another for 45°, and didn't have any problem at all making them.

My saw is a Shop Fox cabinet saw. What's yours?

Does your blade drop down enough to clear the underside of the insert, or does it rub?


Jim Your right, my wrong!!:eek::eek: Just run out to the shop and looked again. The blade does come up correctly and would work.:thumb: I don't know what I did so long ago to make me think that but now I'm glad for this thread as now I'll be making more ZCI's. I've got a left tilt Unisaw now. The last time I tried it was with an old no name contractor's style TS. Either it didn't work back then because I did it wrong or there was something different with the way the old saw worked???:dunno: Good learning lesson for me though:thumb:

Sorry for the bad info Larry! See you weren't wrong twice after all! Just this old fart!:rofl::rofl:
 
ok now royal, its back to me being wrong,, try to take your new insert out and putting it back in again??? then glenn's wisdom prevails:)

Got my brain starting to hurt now.... too early in the morning to make it work this hard:rofl: Wouldn't it be you just lower the blade back out of the ZCI and then lift it out or am I not understanding what you said??:huh:
 
hey i was wrong once today already, then maybe got back to right. then i started thinking aint no way i was right never have been before so i was hoping you could prove to me that i was???
 
I like Glenn's insert.

As for the insert being removed when the blade it at an angle, you would have to remember that you have a vertical plane of the table insert hole, opposed to the angle of the blade. These would fight each other, so lowering the blade out of the insert first would permit it to be removed.

I like Glenn's design. Thanks, I need to try that.

Aloha, from another "castaway"
 
so lowering the blade out of the insert first would permit it to be removed.

I cannot lower my blade out of the insert. My inserts are 1/2" thick so my blade would have to go that far below the surface at "full down" to clear. I have often wondered why manufacturers don't give an extra bit of drop below the surface. On the saws I have owned, at 90* the blade clears the surface by about 1/16" and at 45* it is just proud of the table :huh:.

The chew marks on my pictured insert occur when putting it in and taking it out even with the dado. With no dado I can't get the insert in unless the slot is about 3/8" which is no ZCI in my book :).
 
Thanks to everyone that contributed to helping me out here. Glenn I am especially pleased that you responded since you and i have the same saw. I will PM you for more info.:thumb:
 
I held back a bit because sometimes I start talking even if no one wants to hear it. I thought I would share what Ron and I have been exchanging via PM. Some of this relates to a Bies fence but, you get the idea:

- I prepare the ZCI blank as you do but go ahead and level it in the opening.
- Put a dado outer plate on the saw, set your angle and lower the blade below the bottom of the ZCI.
- Use whatever method you choose to hold the ZCI in place BUT, do not use your fence. As you know the little nylon foot that holds the fence off the table will allow the ZCI to raise up when the blade hits it. The levelers and the clamping method should hold the ZCI firmly in place.
- Raise the dado blade till it cuts the ZCI surface with a slot about 1-1/2" long, maybe less.
- Swap the dado for your blade of choice which should now allow the ZCI to drop in till the levelers hit. If not, swap back and raise the dado a bit further. The idea is to have the actual blade cut as much of the slot as possible. I run TK blades so the dado kerf is too wide.
- With your blade in place, re-clamp the ZCI and raise your blade to the desired height.
- Mark your ZCI with the blade and angle. You may still find it a bit fussy to get it out of the opening, this is why mine appears a bit chewed in the pics.
- Repeat with other blanks for other angles.

This really gives me a safer feeling when ripping off a small strip to make a 22.5* or whatever edge. Any of us who have shot a little "arrow" off the table can relate to wanting this type of cut to be as safe as possible.
 
- Put a dado outer plate on the saw, set your angle and lower the blade below the bottom of the ZCI.

This is what I've had to do as my Delta contractor's saw won't let the blade go down far enough. I actually had to use two intermediate blades. My dado set is only a 6" set (for now) and even fully raised it didn't create a big enough slot to let the ZCI drop down over it. I had to get the 7 1/2" blade from my circular saw and mount that in the table saw to lengthen the slot a little more before I could finally put my 10" blade in and finish the cut.

I too wonder why the manufacturers make the trunion so that it won't drop well below the table top. My previous table saw, an el cheapo Craftsman bench top type, would drop the blade well below the top. It wouldn't cut straight nor would the fence lock at 90 (had to measure both sides of the fence numerous times before making a cut and even though a lot of the time the fence would slip in mid cut) but it would at least drop the blade an inch or so below the table top. ;)
 
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