table alignment

dusty · Post by **dusty** » Tue Jun 03, 2008 12:57 pm

Let me answer your question by saying that if I had another trunnion with the smaller holes, I would drill them out.

I was always able to align my table!!!! It does seem a bit easier now.

Drilling the holes was not difficult. Do start with a sharp bit and lubricate. Drill speed slow.

billmayo · Post by **billmayo** » Tue Jun 03, 2008 1:27 pm

I have been using one of the 10ER (I think) aluminum sanding disks to do my table alignment for many years. I got one that fit snugly on the arbor and used a metal cutting file to take off any high spots. I made a jig using the miter gauge, brackets and clamps to hold the file as I moved it across half the disk with the speed on high. I believe it took a while to do this and it was cheap. I marked it as an alignment disk and keep it stored flat. I only used the alignment rod in the miter gauge to check it each time.

dusty wrote:You had me taking deep breathes there, curiousgeorge.

I expected this plate to be a couple c notes. Woodcraft only wants $50.00. Guess I can go buy four at that price.

No, actually it is spec'd at .003" flatness. I have saw blades that I think are that flat.

At least I think that is what I am measuring. I set the dial indicator up with the tip touching a spot just inside the gullet. Set the dial indicator for zero. While watching the dial indicator, turn the blade VERY SLOWLY by turning the power take off (do not touch the blade). I think the reading that I are seeing on the dial indicator is an indication of two factors. Blade flatness and Alignment of the Table Miter Bar to the Blade.

If I am correct - I don't need a Master Plate. Why? - Because it won't help to get my alignment any better than it already is (not if it is spec'd at .003").

dusty · Post by **dusty** » Tue Jun 03, 2008 4:02 pm

Ed in Tampa wrote:Dusty
Now that the dust has settled and you have had time to think through this whole process, what is your final call?

In your opinion do you think it was a manufacturing glitch versus a engineering design that had the back trunnion holes at 3/8 instead of 1/2?

And do you think it was or was not worth the effort to correct this?

How hard was it to drill out the holes?

Would you recommend someone try to do this themselves or to send their trunnions back to SS for correction?

Ed

I believe we are dealing with the results of a design change. The two trunnions are both made using the basic trunnion and appear to be identical except for the two different hole sizes. The rear trunnion gets part number (514620) and the front trunnion is (514130). Add parts to the front trunnion and you have the front trunnion assembly (514339).

If the holes were intended to be the same, the trunnions would be identical and would not be given different part numbers.

Furthermore, if this was a manufacturing error, statistically we would expect some of those small holes to show up in front trunnions.

That's my story and I'm sticking to it.

I believe it was worth the effort to drill out the holes so that all four are 1/2". The table is easier to adjust.

The holes were not hard to drill. If you are going to do it, needless to say, you need to use a "sharp" bit and lubricate (cool) it.

I believe that anyone who has any business with a Shopsmith has the ability to drill these holes without consequence.

I do have two wishes however.

1. I sure would like to have Shopsmith weigh in on this.

2. If there are any Shopsmith owners out there with late model 520s, I sure would like to know what size holes are in the trunnions.

Of course, if Nick weighed in we might know without anyone else reporting.

I have NO regrets and I'd do it to another trunnion if I was to get one. If you feel that there is no room for improvement in the ease of table alignment, then I wouldn't spend the time. And, I know there are a couple of you who will read this and say "no way"; it's be good all these years so I'm not messing with it.

charlese · Post by **charlese** » Tue Jun 03, 2008 4:23 pm

dusty wrote:2. If there are any Shopsmith owners out there with late model 520s, I sure would like to know what size holes are in the trunnions.

We are aware of the problem and will keep you posted.

Just couldn't resist:rolleyes:

solicitr · Post by **solicitr** » Tue Jun 03, 2008 8:16 pm

My 520 bought this year has all four holes the same and oversize- I assume 1/2" tho' I haven't bothered to measure 'em!

jdp · Post by **jdp** » Fri Jun 06, 2008 12:22 pm

> Get ready to float a loan if you are going to buy one of
> those plates [Master Plate]. They are precision milled
> and don't give them away.

Has anyone measured flatness on the 12" sanding disc?

It is not spec'd at .003 but it seems to work fine for aligning the table.

Nick · Post by **Nick** » Mon Jun 09, 2008 5:45 pm

1. I prefer the sanding disc for aligning the table because it has a larger diameter and you get a more precise alignment because of it. However, I treat it just like I would a saw blade. I mark a spot near the rim and use just that spot to make my mesurements. That way, you eliminate any runout from the procedure, no matter how large or small it may be.

2. The undersized trunnion holes were a manufacturing error. They are cast and machined by outside vendors. Quality Control failed to catch the manufacturing error and several hundred left the factory before we were aware there was a problem.

With all good wishes,

paulmcohen · Post by **paulmcohen** » Mon Jun 09, 2008 10:08 pm

Nick wrote:2. The undersized trunnion holes were a manufacturing error. They are cast and machined by outside vendors. Quality Control failed to catch the manufacturing error and several hundred left the factory before we were aware there was a problem.

With all good wishes,

Do you have a date range for the error?

Ed in Tampa · Post by **Ed in Tampa** » Tue Jun 17, 2008 5:09 pm

Well I finally got to the point where I had some time to check my trunnions.
Guess what? My rear trunnions are 3/8 holes!!!!!!:eek:

Through a whole set of circumstances I ended up with two 510 tables so I checked the other table. Guess what? My rear trunnion on that table were 3/8 holes also!!!!!!!!:eek:

The biggest metal drill I presently have is a 7/16 so I guess I'm off to the tools store to buy an 1/2 drill. I really hope this is worth it!
Ed

dusty · Post by **dusty** » Tue Jun 17, 2008 6:21 pm

Nick has confirmed that the undersized holes that we have discovered in the trunnions are the result of a manufacturing error. It seems that this error was made many years ago; my machine is nearly twenty years old.

Responses to this thread report the status of eight different trunnion pair; of those, only one was reported to have all four 1/2" holes.

One of our problems was resolved by Shopsmith (replaced trunnion), one was reported to not be causing an alignment problem (but purchased a trunnion just in case) and the remaining five of us have chosen to resolve the problem by redrilling the undersized problems.

I am pleased with the results that I have experienced and hope that everyone else has had the same positive results.

This has by no means been a scientific study but it seems to indicate that a number of on this forum have machines that were manufactured at near the same time period.

Many have not responded; I hope this indicates that these folks are so very satisfied by the results of their alignment efforts and that there is no reason for them to dismantled a table just to check. That is very good news.

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