So, I wanted to try the 3/8 option with this set to make some trivets. I needed to get an insert set up so I had installed the blade and then put a board over the top, clamped down. Tried to raise the blade to cut the insert but had to readjust and add another board to hold the insert. Well, apparently on that 3/8 configuration, the teeth "extend" out so there must not be sufficient clearance so it was jammed (not rotating). Wasn't a good time when the saw wouldn't turn back on. Only when I went to remove the two blades did it register that the blades were not able to freely move. After my husband found the red overload button, and I put in a regular blade, the saw seems OK (sounds normal plus made a couple cuts) - although when lowering the blade, there is a slight glitch/hesitation toward the "bottom" position.
Any suggestions on what I should check? Feeling a bit sick that I didn't realize the stack wasn't moving freely (too focused on getting the zero clearance set I guess).
Probably just dust in the screw/gears. Maybe a little housecleaning? My router lift needs attention to the jack screws quite often, but the table saw doesn't. SawStop did a good job on the ducting around the blade and arbor.
Dark_Lightning - I typically vacuum out my saw at the end of each shop day, but good point to check that. I'm just worried if the blade teeth might have damaged anything when I started the saw that first time. The blades looked OK, but I'm no expert on that either.
[Note - free business idea...mobile shop help! This could be equipment checkups, repairs, or setups.]
Barb, FWIW I had the same thing with end of the world sound effects when I jammed a dado at close to 3/4" into a new insert.. Mine didn't stop the saw, but it scared the beegeejeepers out of me. I powered mine down due to the racket. My thought is sawing out a single blade insert like you have to, by coming up through the bottom. Add to that noise, several blades, and all of those extra teeth, and it just adds a din that sounds like it's the end of the world. Did you look at the bottom of the insert, and did it looked pretty chewed up? It doesn't get smooth, until you exit the insert. Probably a lot of noise, and enough stopping force to quit your motor. Are you direct drive, something with a belt. like a contractor saw, or a cab saw with possibly a few drive belts?
If you feel it jammed on something inside the saw, probably best to post make and model, so maybe someone with same/similar saw could weigh in, and hopefully make you feel better about potential, but I really doubt either a 1/4" or 3/8" dado would strike anything on any of the brands I am familiar with, but if it is a smaller direct drive saw, I know almost nothing about them, nor the clearances they have. I do know on a few of them, I have read they do not accept a dado blade, but I couldn't remember which they were, with exception of that little Sawstop. Beside them, most saws these days allow for a 13/16 dado, and have appropriate clearances to make that happen.
BB, your saw is a 10" right? Those box joint blade sets are usually 8" so usually an un-cut insert will clear the blade when all the way retracted. I know that when I cut a fresh insert for a 10" blade, it will retract to maybe 1/4" below the table top so I need a relief cut on the insert underside to allow the insert to be set in place before I raise the blade. If O'm in a rush I'll just install a circular saw blade (just under 8") and cut with that. When I see where the cut is centered on the insert bottom, I'll widen the kerf with a chisle just enough to make room for the 10" blade. If I'm not in a hurry, I run the insert over the router table with a bit (box core or 1/4"straight) to cut a channel for the blade that allows the insert to be fully installed before raising.
Really make me want to set up with one of those inserts that have the slip-in strip, usually 1/4", so I only have to replace that section when refreshing the insert or making one for a new blade.
You can use a router or even a forstner bit to cut/drill out enough room on the bottom of the insert so that blade does not contact the insert before you raise the blade up through it. It may not take much since it may be only a few teeth that might contact the insert.
As for the glitch when lowering the blade, is it possible that it was always there there and you are just now hypersensitive to it because you had a problem.? Does it only happen when the blade is at max height or does it happen no matter what height you start at?
--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.
The issue isn't the insert, but that the "dado" set (really just the two blades) was unable to move when in the configuration for the 3/8-inch cut. I had my air filter, dust collector, and my hearing protection in place so somehow I didn't hear anything of alarm. When I went to raise the blades into the insert, the insert was lifting (which would now make sense if the blade wasn't spinning) so I shut everything down to add another board on top as I had only a ¾ poplar board spanning the insert. When I went to re-try, it had tripped so no starting it. At that point I realized the blades weren't able to move, apparently due to the teeth orientation.
Thus, the concern isn't with the insert as much as if I had done something to the saw by having a blade combination inserted that wasn't able to rotate. I haven't had a chance to get back into the shop to look at the saw, but will look over everything and hopefully be able to move forward. Will check what status causes the glitch (and as Lazyman notes, I may now be extra sensitive to anything amiss). May also call Forrest to see about the blade set as it seems really odd that this could even occur - guessing I did something wrong in my setup.
Note that the insert actually has an "indentation" that allows for the blade to be fine until raised to make the cut - I have one of these for my regular blade and its a nice fit for the saw. Picture of the underside of the insert for dado set.
Should add that the overhang from the teeth over the blade body plate is much greater than regular blades. This can cause binding on some pre-relief-cut inserts that have the arbor side cut not backed off enough
Very odd that the blade set would not spin (there wasn't a spindle lock or other device?) That is an 8" set correct?
Either way, I find uses all the time for the set, especially handy for making tenons and other "dadoing" type operations without the typical dado set bat ears. Amazing clean crosscuts too!
Good catch! It's the tooth overhang. Nut is probably right at 4" from the center of the arbor.
You can add a dado type shim/washer between the blade set and arbor for when you use 3/8" (or both). Sucks that that will be an added step however. If 1/4" works, the shim only needs to be greater than 1/16" (0.063")
The blade spins ok when in the 1/4 - although likely "tight." 🤔
Not sure what type of shim/washer would be ok with the dado stack. I'll be honest-I haven't used my other dado stack on this saw...ever. Funny as I used it on my Bosch contractor saw quite a bit (they had slightly different setup when using dado blades).
Bit disappointed as I like these with the flat cuts. Was headed to make some trivets when things came to a halt (literally 🙄).
I have spoken with both Forrest and Powermatic and neither had heard of this problem. 😬 Do have a email for Forrest to send some pictures to get more recommendations.
Are the teeth hitting that nut? If that truly is 4" in from the arbor center, 1/16" seems like a pretty tight tolerance when you use an 8" bladed spinning at 4000 rpm.
--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.
For best results, you really need a truly flat washer like the shims that come with a dado set, though 1/16" would be a stack since the biggest shim I have is only 0.020" You can buy a 5/8" bore flat washer at places like Lowe's (or most any HW store) for under $1, but these are usually stamped so they would possibly have a slight ridge around the edges. The outer diameter needs to be the same as your current arbor washer that goes behind the arbor nut when installing a blade.
Alternatively, you can buy a "blade stabilizer" which will be flat and plenty thick enough, but they cost more.
I tightened that screw (#178 in the manual). Still just ticks the tooth (just hand held so not snugged in place either). Definitely not possible to use the 3/8 configuration.
Splintergroup- thanks for that added information. I am just struck with how odd it is to have the screw head (#178) of that "height" in that spot. Seem tighter in general than I would want it to be!
I think design wise, they tried to stuff some upgrades in place with minimal rework. It looks like that is part of the arbor lock mechanism/support?
Anyway, clearance with a 10" blade seems sufficient, but the location interfering with an 8" blade is really odd, especially if they make no note/warning about it in the manual. They'll warn you not to use the saw in your shower, but not this detail.
Yes, I think that is part that holds the riving knife and then continues around the arbor. I had to look at the machine schematic on the call so I could hope to communicate with any accuracy.
