Table Alignment (Squareness) Done on the Work Bench

[everettdavis]

Your comments are great and very much on point.

I have some Mark V's that definitely fall into those tolerances.

My Anniversary 520 is an exceptional anomaly. It is tight and right as friend calls it. I have cut very thin material off oak that was jointed very well to begin with.

One of my friends said that's so thin it only has one side, then laid it down on a magazine and read through it. It had an exceptional blade on a 5/8 arbor. It was a 10" Laser Thin Kerf Saw Blade - 1/16" Kerf and that was the blade I used when I wrote "What Can a Single Crosscut tell you.pdf"

Some other members may find something of use in reading it. It speaks volumes once you understand what it reveals.

It's the 2nd PDF at http://www.shopsmith.com/ss_forum/viewt ... 90#p185690

The one above it
"My method to the alignment process - Everett L. Davis.pdf" is what I used to align my 520. It seems logical and easy to do for me. It may work for some of you others as well. There are a number of ways to do alignments.

All those things and points you made above speak to the issues I was trying to illustrate in both.

Everett

[dusty]

You guys are mixing apples and oranges.

My comment about 1/64" precision had to do with the blade being centered in the cutout.

[reible]

Some many years ago I was doing a project for my wife who wanted wooden bookmarks with a shape punched through them. The punches were designed for paper not wood but never the less if one gets wood thin enough they would work.

I wrote about this on an old shopsmith forum that pre-dates this one. I had a link to that thread but they changed software and the link no longer works. I was ripping the wood down to .005" but when it gets that thin all sorts of other issues were coming up like the air flow off the blade and other unexpected events. I finally settled on .007" for the project.

So yes there are woodworking projects that work to that level and I've done one. When one says .007" think of the thickness of 2 sheets of paper and you will be about right. For some these small numbers are hard to imagine and working with them might seem impossible, but it is not.

Anyway I thing I've said enough on the subject so I'm not going to post more on the thread.

Ed

[dusty]

In theory the difference between the thickness of the body of the blade and the kerf divided by two gives you the clearance. Now take into account the angle through the blade caused by the off set from perfect alignment and you have a reasonable acceptable error.

Since blades are different those numbers are different but just as an example say I have a blade with a width of cut of .094. The body is say .084 then the difference is .010 so we half that and the number is .005. Now I don't have real numbers here but I could or you could but that is how one can come up with a base number.

When you do that with a real blade you would want to pick the worst case you have, ie the one with the least difference between kerf width and body thickness. I'm guess that those number are not a constant between manufactures and maybe even styles of blade.

Interesting enough a cheap blade might make things better as it might have a wobble dado effect??

Ed

I did what you suggested to determine the base number for a specific blade (the one on my Mark V for months). Yes, using that method produces a base that is greater than .005". But that is the base. Why do you now say that the number (.026" worst case) is unacceptable because it is >.005". You have confused me which you normally do not do. I thought that the base (as you called it) was the number to strive for for this specific blade.

[dusty]

Shopsmith list several part numbers for rubber bumpers (517135, 517113, 516667). Does anyone have the part number for the 1 3/8 bumper. If I can get one of those I think my blade will finally center. I have the 1 7/16 bumper now and I'm still a little off of center. (Of course many people that know me will attest that I have always been a little off center.)

Michael

Yes, there are different rubber bumpers. Which one is the right one? I don't know and the Shopsmith documentarion does not tell me. But why are there different bumpers? Masybe because there are different headstocks and maybe even carriages.

Does this little nib (which does not exist on all headstocks) affect spacing? Absolutely. But which one goes where?

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