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Re: Truing, As Best You Can, Shopsmith Table Tops

Posted: Mon Sep 07, 2015 7:17 pm
by joe_cool
Dusty, One Question, on your shopsmith do you have the double tilt base or just the standard bases?

Re: Truing, As Best You Can, Shopsmith Table Tops

Posted: Mon Sep 07, 2015 7:29 pm
by joe_cool
Dusty, this video is what I was following when i was attempting to align the extension table. Fast Forward to 8:45 in the video they align the extension table on both ends of the mark 5.

https://www.youtube.com/watch?v=ovOxlGMp8SA

and Continues to this Video:

https://www.youtube.com/watch?v=_-Mt-P1efbU

Re: Truing, As Best You Can, Shopsmith Table Tops

Posted: Mon Sep 07, 2015 8:19 pm
by JPG
I have seen that before and seriously doubt that adjusting the set screw will correct the problem shown.

What I see is the straight edge pivoting on the outboard side of the main table. Adjusting that set screw rest will twist the way tubes only. It will not alter the planes that caused the 'rocking' so as to correct that.

Also the lock needs to be adjusted whenever that stop screw is moved.


In other words, the video is contrived. I doubt my perception of 'perfect' is the same as the future(?) Mrs. Doug Reid. ;)

Re: Truing, As Best You Can, Shopsmith Table Tops

Posted: Mon Sep 07, 2015 8:31 pm
by dusty
joe_cool wrote:Dusty, One Question, on your shopsmith do you have the double tilt base or just the standard bases?
I do not have the double tilt base.

Re: Truing, As Best You Can, Shopsmith Table Tops

Posted: Mon Sep 07, 2015 8:35 pm
by dusty
If I had two set screws (one on the infeed side and one on the outfeed side), I might buy into the set screw proclamation. With my machine, I need to lift the side that has no set screw to accomplish what they did in the video.

No, I don't buy it. You can find some Sawdust video that proclaims the same thing.

Maybe, if the floors were perfectly level and flat and the machine was assembled there and the tubes are all straight and .......

Think about it! Why are the Extension Tables adjustable. That adjustability was put there for some purp[ose and I believe we are discussding it.

Re: Truing, As Best You Can, Shopsmith Table Tops

Posted: Mon Sep 07, 2015 8:43 pm
by joe_cool
I wonder if John Burger after doing his double tilt upgrade if his extention table aligns on both ends?

Re: Truing, As Best You Can, Shopsmith Table Tops

Posted: Mon Sep 07, 2015 9:35 pm
by JPG
I am not sure 'they' accomplished anything. I noticed the extension table tube retaining knob was NOT tightened at the 'end'.

So Dusty your extension table is 'low' at the front? Does the tie rod rest securely on the set screw?

FWIW, I consider the use of the rails(rather than the tops) as a 'reference' is a diversion.

I cannot help but notice the table cant in the video is the same(but opposite) as the first post in the 'other thread'.

I do not know of a way to change the 'lean' of the end castings. I would be suspicious of the initial table adjustments particularly with the table perpendicular to the blade vertically.

Re: Truing, As Best You Can, Shopsmith Table Tops

Posted: Tue Sep 08, 2015 12:53 am
by JPG

Re: Truing, As Best You Can, Shopsmith Table Tops

Posted: Tue Sep 08, 2015 6:11 pm
by jsburger
joe_cool wrote:I wonder if John Burger after doing his double tilt upgrade if his extention table aligns on both ends?
OK, I don't remember nor can I find the thread I wanted to post this to but it is relevant here so here goes.

This was all done on my MK 7. First I checked the table tilt to the blade. It was dead on 90 degrees. Then I checked the miter slot parallel to the blade. I am off 0.005". Close enough and not worth fooling with. Then I checked the main table for flatness. It is not perfect but not bad. Left to right across the front the right corner is down about 0.008". Across the middle the right edge was down about 0.006". Across the back end it was flat. Diagonally left front to back right it was flat. Diagonally right front to left rear the front corner was down about 0.008" as expected.

Next I installed my two fixed extension tables leveled them with the main table and checked for co-planer with the main table. They were both off slightly left to right. So I thought I would use Dusty's method using the connector tubes. I have four short tubes and none of them are perfectly straight. I rolled them across the Powermatic cast iron table top and they are all out 10+ thou. Anyhow, I loosened the bolts on the right extension table, slid the main table to the right, installed the connector tubes and tightened the locks. The back of the table came up fine but the front was low about 0.030". Huh :confused: OK the fence is misaligned. I got out the fence gauge and sure enough it was too low. Huh, that is the wrong direction. :confused: :confused: So I abandoned the tube idea and went with the straight edge. I still have no idea why the tube did not work on the front. I got everything level and co-planer on both extension tables with the straight edge as I have always done.

Once everything was level and co-planer I checked diagonally across the entire surface using Dusty's method with a string. I don't have a straight edge long enough either Dust. You said something to the effect that the results are far from perfect. Well, my results are as close to perfect as I think you can get. It is pretty hard to tell from the pictures but those strings are dead straight when you sight along them and if there any gaps to the table I couldn't see any.

Now for the question of swapping fixed end tables on the MK 7 with no alignment problems. No quite. Next I swapped the tables. The right table on the left side was fine. The left table on the right side was not. It was not co-planer left to right. It was not much, 0.030" or so, but not perfect.

BUT there was another interesting issue. When I swapped the tables the left table was 1/8" lower than the main table and the right table was 1/8" higher than the main table. Remember I use adjustable stop collars on all my tables so when I drop them in there is no change. Again Huh :confused: :confused: :confused: how can that be? The only way is if the main table is not parallel to the way tubes. Remember the main table is dead square to the blade. I measured from the top of the way tube to the top of the table on both sides. The left side is 1/16" higher than the right side. That corresponds perfectly to the difference I saw when swapping tables. You can see the difference in the pictures of the level. Oh, notice how level my floor is. :D :D This may or may not be a MK 7 issue. It seems to me that there are two things that can cause this. The way tube holes and the table tube holes in the carriage are not 90 degrees (not a MK 7 issue per se) or the way tube holes in the double tilt end castings are not in the same vertical plane.

Re: Truing, As Best You Can, Shopsmith Table Tops

Posted: Tue Sep 08, 2015 8:37 pm
by dusty
I am disappointed. I would have bet that the Extension Tables would swap end for end and be perfectly aligned.

Using the handy dandy level that is shown here, are all of the tubes (Way and Bench) and the Main Table at zero tilt all level (or at least out of level by the same amount in the same direction).

Does your carriage slide smoothly on the Way Tubes. If it does, I doubt your hypothesis of the carriage holes being a contributor.

After checking the Way Tubes and finding them dead on, check the Main Table legs for vertical. That will likely dispel any thought of problems with the milled holes (vertical or horizontal) in the carriage.

I apologize in advance for thinking and/or saying this but I suspect an operator error. I have far too much confidence in Shopsmith quality to buy those theories.

Good Luck. At least you don't have to consider the possibility of the floor causing any of this anomaly.