radial arm saw has 20 thousandths of wobble in the blade

[HANK METZ]

If the inner faces look clean, examine the outer, working edges. They may be galled or have metal upsets that prevent them from seating properly. I'd simply stone inside and out surfaces ever so slightly, reassemble, check again for deviation, it may be all it takes.

[cody michael]

I do not know if they are the original ones but they are not flat, the inner portion is recessed and the only part that touches the blade is about 1/4 in from the outer edge.

I cleaned up before arbor washer before I reassembled last night and it didn't make any difference.

I am not sure how to put the indicator on the where to washer hits, it is pretty small, the lip i could use is smaller then the tip of my indicator.

[cody michael]

I have a grinding stone I picked up today, any ideas on how to keep the arbor washer held in place accurately while i grind it?

[Myk Rian]

I have a grinding stone I picked up today, any ideas on how to keep the arbor washer held in place accurately while i grind it?

Read Ronalds post a few up.^^^^^

[Duane Meadows]

One other thought... the outside blade washer should be the same diameter as the inside one. If not, or if you don't have the outside washer, tightening the nut can really distort the blade! Just a thought.

[cody michael]

There is an outside washer. It's just not in the picture, they are the same size

[Duane Meadows]

Cody, what's the model of that saw? Did you try exchanging them?

[Rick Potter]

The washer in your pic looks like a stabilizer accessory to me, Cody. Check the online manuals for your saw, and see it that is what the arbor washer is supposed to look like.

Is it steel?

Rick P

[Mike Null]

I have two ideas, neither of which may be relevant. 1. Is the motor/blade exactly perpendicular to the table and is it exactly perpendicular to the fence? 2. Try a 4" blade stabilizer.

[Myk Rian]

I can see this whole thing going south.
Cody, find someone that knows machinery to help and advise you.

[David Eisenhauer]

As Duane said, did you check to see if the wobble you have exists in the motor shaft? This needs to be done first before you chase a problem that is not the real problem. If the arbor is OK, then you will either have to try and flatten out the flange washer on the saw or off the saw. Without being there, it would seem to me that removing the arbor flange from the saw and spinning it down against a stone would be easier (paint the surface with Marks-A-Lot to check on progress). Or, use some spacer washers and a nut to hold the flange tight against the arbor for truing in that fashion. You may have to grind down some washers and another nut to expose enough of the outer rim of the flange washer to push the stone against. At some point, you will need to try something.

[Duane Meadows]

Put a mark on the arbor, and a mark on the washer. Turn the washer 1/8th of a turn reinstall blade and recheck the runout. Do this for a full turn. If it follows the washer, the washer is the issue. If it stays in the same position relative to the arbor, then the arbor/arbor bearing surface is the issue.

Being that the washer is removable, flattening it off the saw would be much easier. Both surfaces of the washer need to be parallel(perpendicular to the arbor hole as well!). Work carefully! It will likely require removing only a very few thousandths of an inch from the high side. Marking as above will help in determining the where that high spot is!

On my saw the inner and outer are very similar, if not indentical. Thus I would reverse them and check the runout again. If it decreases, pretty good indication the inner washer is at fault!

Myk, it really ain't rocket science! I spent 30+ years as a tech for Sears. Have worked on many a RAS over the years.


Also, though very important, blade alignment to the table, the arm, or anything else will not cause blade runout. It will of course cause quality of cut issues!

[Paul M Miller]

Is the hex spacer loose on the shaft. or fixed? Before I did any grinding, I would assemble the blade, washer, and spacer on the shaft, then make a mark on all three so that alignment can be duplicated. Check the runout and mark the outside of the blade at it's highest point. Then alternately rotate each of the 3 components 180*, checking runout with each configuration. This should tell you which component is out of whack. Long story short, if you grind away on the washer and it was the spacer or blade that was bad, you'll have the same problem unless all the components are aligned the same every time you put the blade on.

Come to think about it, I would add the shaft to the list, making it 4 components as variables.

Paul

[cody michael]

I worked on it today, got it down to 8 thousandths wobble then ran out of time will try for better tomorrow, what is acceptable for this?

[HANK METZ]

I worked on it today, got it down to 8 thousandths wobble then ran out of time will try for better tomorrow, what is acceptable for this?

That is a personal preference, anywheres from 0.0" to .008", depends on what you deem acceptable- the real test is to make a shallow kerf in scrap, compare it to the blades' tooth width. Good work though, once you took the plunge it wasn't all that bad now was it?