# Blade alignment on my Craftsman table saw



## lepton (Mar 24, 2012)

I've got a used Craftsman tablesaw, model 315.228410, and the blade seems to be out of alignment. When I measure to the miter slot, it's 4" on the front but about 3 7/8" on the back--nearly an 1/8" out over the 10" blade. Doesn't that seem like a lot? I have the manual, and it says that I need to loosen 3 bolts on the rear bracket. These bolts seem to hold the bracket to the underside of the table, and the trunnion rests in it and swings in a slot when the bevel handwheel is turned. The problem is, these 3 bolts don't seem to sit in slots of any sort; they seem to thread through the bracket into threaded bolt holes. Since there's no side to side movement, I don't see how I can pivot the blade and improve the alignment. I know several users on this forum have this saw, so I'm wondering if you have blade alignment issues, or can clarify how to align my blade. Any help would be greatly appreciated. Thanks!


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## Woodworkingkid (Jan 8, 2011)

I know exactly what your talking about I have almost the same saw. I have spent the last week trying to get my crapsman table saw aligned. I have spent close to 8 hours on it with no luck.:furious::furious: I have one from the early 90s that was given to me and im about to give it back . Sorry if I seem a little mad I just got done trying to do it and its not working. I don't get either why the bolts don't sit in a slot. I have been taking a look at the new saw sears sells and am really thinking about getting it. Sorry I wish I could help you more


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## woodnthings (Jan 24, 2009)

*Posted in a similar thread*

You can not work with only the rear trunnion bolts! You have to loosen the front also, and pivot on the front center bolt. 








*remove 4 bolts* 
Leave the center ones just slightly loose and see if you can rotate the arbor and carriage assembly by hand to get the blade parallel to the miter slot. 

It if will line up, then tighten the 2 center bolts. Then insert the remaining bolts one at a time and snug them up, then give everything a final 1/4 turn more.

If it won't line up using the 2 center bolts, your trunnion holes will have to be slightly enlarged and you need to figure out from the top down which way to elongate the holes. It won't take more than a few stokes of a 3/8" round rat tail file, but it will mean either removing the trunnions or dropping the whole assembly down. If you need to drop the whole assembly it's a good time to really clean out and wash the trunnions from any old grease and dust. Also remove any addition loose parts to reduce the weight. 
If possible turn the saw upside down on it's table....yeah, I know it's a PITA, but this is a one time only process and you may as well do it right.... Been there, done it myself. It's also much easier to see which way to enlarge the holes and which ones upside down. Use star washers under the bolts and you'll find a 3/8" ratchet with a 12" extension will make life a whole lot easier. 
Now, to align the blade to the slots turn the saw on it's back end, so you can see the bolt holes and still measure to the miter slots. I use a tri-square set to the closest dimension possible and check front and back on the same tooth rotating the blade. Once you get the same reading, again tighten the center bolts and replace the outer ones and tighten them also. RECHECK for parallelism. 
 bill


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## lepton (Mar 24, 2012)

Thanks Bill, that was very helpful. I think I understand the mechanism now: The trunnion holes are slightly oversized, and by rotating the trunnions rather than sliding them, we can change the blade's alignment to the table. I found that by standing at the back and lifting the motor, I could improve the alignment quite a bit. Sometimes when I retighten the bolts though, they want to fall back to their old positions (even the rear centre bolt) so it's very difficult to maintain perfect alignment. However it's much better now than it was (< 1/16" I think) and I think I'll leave it at this until I have the opportunity to flip the saw and enlarge the trunnion holes as you suggested. I'm building a cabinet for the saw anyway, so I'll take care of this when I take the legs off.


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## Kirby Hidy (Apr 3, 2012)

Consider adding PALS to your saw. Helps keep alignment solid. Not expensive and I believe they offer a set just for Craftsman saws.


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## rwilkins (Feb 9, 2020)

PAL do not make a set that fit the 315 series I found out from the alignment folks


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## FrankC (Aug 24, 2012)

When we ran into the problem of not being able to move a printing unit enough to tram it up we removed the bolts and turned the top of the bolt shank a bit smaller.


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## woodnthings (Jan 24, 2009)

*You had a lathe?*



FrankC said:


> When we ran into the problem of not being able to move a printing unit enough to tram it up we removed the bolts and turned the top of the bolt shank a bit smaller.



Most woodworkers would not have a metal lathe, so a rat tail file is the tool of choice. It does require removing the trunnions however, a pain in the neck. Grinding down the bolt shoulder would also work. But unless you "clocked" the bolts orientation when were tight, you'd need to grind them all the way around..... :sad2:


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## FrankC (Aug 24, 2012)

woodnthings said:


> Most woodworkers would not have a metal lathe, so a rat tail file is the tool of choice. It does require removing the trunnions however, a pain in the neck. Grinding down the bolt shoulder would also work. But unless you "clocked" the bolts orientation when were tight, you'd need to grind them all the way around..... :sad2:


They could also purchase a square or triangular file, remove the bolts one at a time and file around the shank without having to disassemble the saw.


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## NoThankyou (Mar 21, 2018)

This thread is 8 years old. Answering ancient threads is a common problem especially by new users trying to become a productive member of the community. Not a big deal, rather just a fact.

While it may be too late, a suggestion here is that the trunnions need to be slid around to align the blade. 

A word of caution. The washers under the bolt heads are probably warped. Re-using those washers will prevent you from ever aligning the blade. The suggestion here is to purchase hardened washers. These are more commonly found in garage door parts packaging.


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