How do I align my table saw blade parallel to my miter slot?

Hello all, on my Delta table saw 36-979 it offers the following advice for aligning the miter slots to the blade.

On page 24 of the delta manual for table saw model 36-979 the adjustment for the blade parallel to the miter slot is not working for me.

In figure 68 it says to loosen 2 hex bolts B that hold the rear trunnion C and pound trunnion C until the blade is centered in the table insert. I pounded that thing for 10 minutes and it did not budge once. The front of the blade is skewed inward slightly (1/32 to 1/16) compared to the rear of the blade and it is nowhere near the center of the table insert. What am I doing wrong that I cannot budge this trunnion? Please offer help if you have had this problem before.

Thanks.

Reply to
rugby17043
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I guess you should be OK if what you are doing is described in the manual. However, FWIW, the blade should be aligned to the fence and then the slot to the blade. Do not align the blade to the slot (as in your subject line) Maybe its just the arrangement of terms.

Reply to
Joe Bemier

How do you align the slot to the blade since the slot is fixed in the table top iron? Everything should start with the most difficult to align to the easiest. So in order, it goes slot (which is fixed) then align the blade to be parallel with that slot, then align the fence to be parallel to the blade.

If there's some other method then please tell me, I'm all ears.

Reply to
Upscale

Hey Joe, Are you sure this is what you meant, "> However, FWIW, the blade should be aligned to the fence and then the

the trunions and blade relative to it. Any fence sytem should then be adjusted to the blade, or to the slot, since the slot is the reference point of blade alignment. By the way to Rugby17, are the slots paralell? I hope there was not a machining error at the factory but it won't hurt to check this detail.

Marc

Reply to
marc rosen

Align the blade to the slot.

Most fences are attached to the table. When making the second adjustment you propose (aligning the slot) the fence will no longer be in alignment. Also, the fence is not a precise alignment. I believe the offset is about 1/64 to the right (away from the blade) at the rear of the table. Yes, this does cause the potential for kickback when the fence is used on the left of the blade so adjust accordingly.

To align my blade to the slot, I used two drafting triangles with a square steel insert in the slot. Works great

Reply to
A.M. Wood

Forget about the trying to line up with the table insert. You want the blade parallel to the miter slot and the fence. That said, I had a similar problem with my Jet contractors saw. The instructions said to loosen the back trunnion and adjust 'with a block of wood' and a hammer. It wouldn't go far enough so I had to loosen the front trunnion and move it in the opposite direction.

Reply to
RayV

1/16" is a lot to be out.

  1. With small C-clamps, Clamp each end of the carriage to the trunnion brackets so that the carriage is locked between the brackets. Alternativly, use along bar clamp to clamp the entire trunnion carriage mechanism together. The idea is to not end up with the carriage assembly loose between the trunnion brackets.

  2. Loosen each hex bolt individually, remove, throw away the flat washer and replace with new (the clearance hole in the trunnion bracket is relatively large, the washer may be deformed and have "memory", going back to the same place when you tighten). Snug up the HHMS (but don't fully tighten) with the new washer in place. Do each of the four, one at a time so you don't lose what you have.

  1. Tap the carriage assembly until you achieve alignment and are in the center of the insert. Tighten all four screws. Raise the blade to full height and hand spin to check insert clearance, side to side and front to back. Tilt the blade all the way over to 45 degrees and spin it again to check insert clearance.

  2. In the event that you do not have enough clearance in the trunnion bracket holes to both align the saw and maintain proper blade clearance, the parts are dimensionally defective. Call Delta.

Frank I represent no one but myself

Reply to
Frank Boettcher

When I read those instructions, it looked to me like you should also loosen the front trunnion bolts. Perhaps the front trunion is holding you back. Jim

Reply to
Jim

You have to also slightly loosen one of the front trunnion bolts so the whole mechanism can pivot about the remaining tight bolt.

I'd also suggest strongly that you get the PALS alignment attachment. Makes the whole thing a lot easier.

Reply to
Larry Blanchard

Well, it seems you use the factory insert - I don't. I have a variety of inserts - all shop made to provide riving knife, zero clearance, etc But even if I did use the original I would set my saw up Fence-Blade-Slot. The slot is a default position (it ends up where it ends up) after the fence-blade is correct. IMO, you should start with alignment of the fence parallel to the table...then fence to blade ...then the slot is defaulted. However, in any well made machine there should not be too much adjustment of the slot required if you follow the above. I'd suggest that the slot is nothing but a hole that belongs where the blade come up after proper alignment of the critical parts.

Reply to
Joe Bemier

I'm referring to the mitre slot that runs the width of the table saw, not the insert with the slot that the blade comes through. The insert has absolutely nothing to do with the alignment of the blade other than sitting properly without touching the blade.

Reply to
Upscale

My mistake! Apologies for misinterpreting the original message.

Reply to
Joe Bemier

First, you need ALL the trunnions to be loose-ish. In addition to the bolts, remember that you have a locked-vertical tilt that is adjusted with a shaft to the handwheel; you have to make sure that handwheel is loose (i.e. that the backlash of the handwheel is NOT taken out) or that shaft acts as a strut to keep the trunnion fixed.

Avoid pounding if possible; a rawhide hammer or prying with a wood wedge are usually enough.

Reply to
whit3rd

Good point, I never thought to loosen the tilt wheel when aligning the blade.

Reply to
RayV

Hi Joe,

I would beg to differ. As the manual describes, the blade and the fence should both be aligned parallel to the miter slot. The miter slot is long and machined, making it a good alignment reference. As you have described it, the blade would be the alignment reference. This would be OK except for the fact that the blade is short and usually warped. It's like the small rudder being used to turn a large ship. A small warp in the short blade will be magnified by the long length of the fence and the miter slot. This is more important than most people realize since as little as 0.005" of misalignment can adversely affect the quality of the cut.

Reading through other responses I recognize yet another problem. Whenever possible, you want to make sure your alignment proceedure is "order independent". In other words, you don't want one step to adversely affect the accuracy of another step. For example, if you use the blade as your alignment reference, then your blade/slot alignment will adversely affect the accuracy of the blade/fence alginment. So, you are forced to do the blade/slot alignment first, then the blade/fence alignment. If you use the miter slot as your reference, then the blade/slot alignment is independent of the fence/slot alignment. Changing one will not adversely affect the other.

Finally, I also noticed someone recommend adjusting the fence "about

1/64 to the right (away from the blade) at the rear of the table". This is not a bad idea if you are us> I guess you should be OK if what you are doing is described in the > manual.
Reply to
ejb

Hey Ed,

I made an error in reading the original message. For some reason I thought the OP was talking about the insert slot. Thus you are correct and sorry for the confusion.

Thx, J

Reply to
Joe Bemier

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