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View Full Version : Arbor and miter slot not in alignment on my Delta Contractors table saw



Mike Manning
01-12-2017, 8:52 PM
I'm considering doing some alignment on my Delta Platinum Edition Contractor's saw (36-475). I checked it today and it's withing .003" of perfect but thought the practice of doing it for when I really need to might be good. I found a previous thread here where some people highly recommended PALS. Sounds like it could make it pretty simple and easy but after reviewing this http://www.newwoodworker.com/algntruns.html I had some questions about how PALS works and concerns.

I also wanted to get some thoughts from people who've aligned their saw blade/arbor to the miter slots. The link above suggests removing the drive belt before performing the alignment. How necessary is that? I understand that virtually everything could impact the alignment like loosening the trunnion bolts, tightening the trunnion bolts, removing the drive belt, replacing the drive belt, etc. Just seems like performing the alignment with the drive belt on would be easier. The link above also mentions loosening the front trunnion bolts and why that's important. The PALS video doesn't require that and it made me wonder if there's much danger to breaking/cracking one of the front trunnions using PALS because they made it sound like it's happened to more than a few who tried to adjust the rear trunnion and didn't loosen the front trunnion bolts.

Anyway, I'd appreciate thoughts on what people have found works best and is most accurate AND easiest. I feel really comfortable right now being under .003" but I think this is good stuff to know and have experience doing.

PS Just noticed the title. When I started this thread earlier today my alignment appeared to be off .011-.012". That measurement was due to some slop in how I'd setup my dial indicator. Once I fixed that I had less than .003" as noted above.

Thanks as always!
Mike

Joe Kieve
01-13-2017, 8:21 AM
I'd say if you're within .003..."if it ain't broke, don't fix it!"

glenn bradley
01-13-2017, 8:30 AM
.003" is pretty good for a contractor saw. I think you will find that if you bevel the blade to 45 degrees those measurements will change. This is a behavior with nearly all contractor format saws. The trunnions, carriage, frame, etc. have been built to reduce weight. This results in a lower rigidity that has a hard time compensating for the weight-shift of the motor.. This is not broken, it is just a fact of the design.

If you are hesitant to take the belt off I would not start trying to align the saw. Removing the belt is the least of the effort required. That being said, I got my 1970's C-man contractor to .001" at 90 degrees using PAL's. Once I got some practice in I ws able to align other peoples saws with the standard block of wood and a mallet with some proficiency. A skill I hope I have lost ;-)

As to the PAL's video and not loosening all bolts . . . if you put torque on the trunnion at the rear and it cannot pivot at the front . . . well not good. Contractor saws can have 3, 4 or even 5 bolts (I've never seen 6 but, what do I know?) so the video has to be a little flexible and general. The PAL's adjustment depends on a few things. There needs to be enough adjustment range from your starting point to achieve your goal. All bolts are left snug with one front bolt left "snugger" so it will act as the pivot point.

I found that I did not have enough range when starting from the setting I had. I simply loosened all bolts a smidge and shifted the trunnion to the left (or right), snugged all bolts, made one "snugger" and began again. The PAL's allow a quick, precise tweaking toward your goal. Now, depending on the quality of the trunnion, frame, etc. when you put the belt back on (and therefor the weight of the motor) things will shift. I slip the belt back off and make an easy adjustment with the PAL's and re-check.

I probably should have said this first but, the most important step that leads to successful alignment of a machine is the allocation of time. I apply the same rule when I try to do plumbing as I stink at it but, I digress. Do not try to squeeze in a machine setup. This only leads to frustration and an unhappy household. I pick a Saturday, have breakfast, take my coffee out to the shop and don't plan to be disturbed for several hours. If it only takes 30 minutes; bonus! If it takes 2 hours, well I still have plenty of time left over.

P.s. It is interesting to note that the trunnion alignment system on my current cab saw uses the same principle as the PAL's. You loosen a stop on one side to make room and 'tighten' the other stop to shift the trunnion over to meet it.

Cary Falk
01-13-2017, 8:41 AM
Pals are great. I ad a pair on my Delta contractor saw. As said if you tilt the blade you will rack the trunnion and you will have to align the saw again. I could tweek the alignment on my saw just by pushing on the motor.

Charles Lent
01-13-2017, 11:04 AM
Even with PALS you are not likely to get it closer than .003". I say "leave it alone". You are woodworking, not making parts for the Skylab. A piece of wood can change size more than.003" over night due to moisture content changes. I don't know how you have determined the .003" error, but your measuring method might even be this far off.

Removing the drive belt eliminates the sideways pull, making it easier to adjust the position and then tighten it up without it moving on you.

Wait until something happens to knock it out of alignment, before messing with it. If it ain't broke, don't try to fix it. It may cost you hours to get it back to where it is now.

Charley

Mike Manning
01-13-2017, 11:35 AM
Thanks for sharing your thoughts. I ordered the PALS last night. I won't bother using it until I know my alignment has changed for the worse. To answer Charles' question about how I tested it I used the miter slot left of my blade with a dial indicator. It showed between .002 and .003" negative change, actually closer to .002. To Glenn, I'm comfortable with removing the drive belt I just thought leaving it on might negate another factor to deal with the alignment.

I now understand that alignment is something I need to constantly check before using my TS. All the more reason to get my Uni put back together and in use. Thanks guys!

Andrew Hughes
01-13-2017, 1:44 PM
I think it's great that your trying to get the best out of your saw.All your work will pay off when you put a good quality baled on it I prefer woodworker 2 from Forrest.But there are many others to choose from.A good blade and a well tuned saw is a joy to use.
I also agree with Charles your never gonna get work from sky net with that saws alignment out.:D

Mike Manning
01-13-2017, 8:32 PM
I think it's great that your trying to get the best out of your saw.All your work will pay off when you put a good quality baled on it I prefer woodworker 2 from Forrest.But there are many others to choose from.A good blade and a well tuned saw is a joy to use.
I also agree with Charles your never gonna get work from sky net with that saws alignment out.:D

I put a Freud Industrial TK GP 40T blade on it last year. Been pretty happy with that. I'd like to have a WWII also but they're pricey. Maybe this year. I do want to check out the Delta 35-7657 40T GP carbide blade sold by Cripes Ind which several folks here have recommended in the past. Hope that is still considered a good quality blade. ???

I have a Freud Super Dado set. Today I was preparing to cut some 3/8" dados in BB plywood. I was recutting a ZCI I bought used to accomodate the 3/8" cut. I had a white wood 2x4 clamped over it on my table saw and the saw stalled 4 or 5 times before I ever got it to max height. Is there something wrong or is this just THAT underpowered? For those not familiar with the Freud Super Dado that 3/8" dado is actually .375".

Andrew Hughes
01-13-2017, 8:57 PM
It could be the dado blade is a lot for that motor.
Was it like new sharp?Do you have the saw plugged into a cord that's properly sized.
Hopefully not a 100 ft weed wackier cord.
Ive used dados sets on job site saws.Just for rebates very shallow cuts can't expect too much from a little motor.

Johnny Barr
01-14-2017, 3:54 AM
Even with PALS you are not likely to get it closer than .003". I say "leave it alone". You are woodworking, not making parts for the Skylab. A piece of wood can change size more than.003" over night due to moisture content changes. I don't know how you have determined the .003" error, but your measuring method might even be this far off.
Wait until something happens to knock it out of alignment, before messing with it. If it ain't broke, don't try to fix it. It may cost you hours to get it back to where it is now.

Charley

+1 +1 +1 +1 ......

I'd kill for an error of .003. Mine was about .006 when I measured it and you want to know something, cuts are dead on square, parallel and smooth without any burning or teeth marks. If you are getting clean accurate cuts then put away your dial indicator and start making something.

Mike Manning
01-15-2017, 11:00 AM
It could be the dado blade is a lot for that motor.
Was it like new sharp?Do you have the saw plugged into a cord that's properly sized.
Hopefully not a 100 ft weed wackier cord.
Ive used dados sets on job site saws.Just for rebates very shallow cuts can't expect too much from a little motor.

Andrew,
You nailed it with an improperly sized electric cord. I normally use a 12-gauge cord but that day I hadn't planned on sawing but just decided to make that ZCI real quick. Plugged into a 16-gauge cord. Retried yesterday and no problems at all with the 12-gauge.
Thanks, Mike

Andrew Hughes
01-15-2017, 2:17 PM
I'm happy for you simple fixes are the best!