Truing, As Best You Can, Shopsmith Table Tops

[dusty]

OK, now here is the rest of the story.

To answer your second question Dusty, they were aligned one on the right and one on the left. Remember, this a MK 7 which some have said eliminates the alignment issue since both ends are the same. That may be true if both ends actually are the same. Remember I have four main tables here. Three had the way tube and table support tube holes at 90 degrees and one did not.

Well, my right hand end casting appears not to be the same as the left one. After zeroing the gauge on the blade and checking the table tops and way tubes, I checked all three table support tubes. As you can see the left hand extension table tubes and the main table tubes are fine. However, the right hand extension table tubes are not 90 degrees to the way tubes. They are tilted slightly to the left.

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As a result when you swap the tables end for end they no longer line up left to right. They are still fine front to back. They are both off very close to the same amount and in the right direction given the tilt of the right hand end casting holes. The straight edge placed at the back of the tables shows the same result.

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I also measured the left hand table tube installed on the right end. It is off (within the tolerance of the gauge) the same as when the other table was installed on that end.

Edit: Correct picture now.

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The results of the Wixey on the table top is consistent with the amount the right end casting is off. Both tables are off the same amount and in the proper direction.

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So in my case with a bad end casting the tables are not interchangeable. Just because the castings are the "same" does not necessarily mean they are all machined perfectly. Of course my right hand one could be within the print tolerance but in my opinion if it is that is a very loose tolerance.

John, in mage three and four there appears to be a slight tilt in the extension table legs. If you rotate that table 180°, does the tile change to the opposite direction?

Dusty, please re read the post. Those two pictures are of two different tables in the right end. As I explained in the post. the tables were aligned with a straight edge to the main table . Then the measurements were made with the Wixey. As first aligned the posts of the left and main table are parallel to the blade and 90 degrees to the table tops. The right extension table posts are not parallel to the blade. Then I switched the extension tables end for end and the deviation remained on the right. After the switch the left extension table posts are still parallel to the blade. Hence the right end casting is not bored square. That conclusion is also borne out by the extension table top no longer being level left to right when the tables are switched end to end.

I caught all of that John. I was just looking for a different verification of your conclusions. If your conclusion is correct, would this end casting now be covered by warranty?

[JPG]

Since this has evolved into a Wixey discussion, please clear up a couple of things that are 'bothering' me.

First, does the slope indicator do as Dusty stated(diamonds[squares] on both sides of the slope pyramid when 'dead level')? The manual pix shows that, but in the display description section only.

Second your pix show the slope indicator to be reversed from the manual description. When the virtual 'spirit level' indicator places the bubble right(indicating the right side is 'high'), the slope indicator in your pix is also on the right which should mean the right side is low.???? That is reversed from both the manual and 'intuition'.

Glad you got the 1/8" nailed down.

I am concerned re the right base casting spt bores not being normal to the way tubes. Could that be caused by slop/clamping?

[dusty]

No, Ed I do not believe that you will get a good summation of this thread. I have read it from beginning to end at least three times, trying to formulate in my mind exactly what transpired. I don't even know for sure what is happening on my own machine. You said earlier that everything works just fine on yours. Just keep aligning it the way Nick said to do it.

Closing Comment: I was very disappointed at how few users contributed. I was disappointed because I know that many of you experience this same issue but never said a word.

[sehast]

Dusty,

I have been following this thread closely because I have never gotten my tables aligned to my satisfaction since I upgraded from a 510 to a 520 several months ago. There are several techniques covered here that are new to me and I am in the process of trying them out. I plan to give a full summary of a step by step process for table alignment, at least as I see it, when I am done. Its just going to take some time.

Steve

[rjent]

To be honest Dusty, I am in awe that this kind of precision is possible, much less required for cutting wood. I was fascinated by what you guys were talking about (and I did ask one question ) but felt inadequate with my still (but growing) limited experience with these machines ....

After following this from the beginning, it makes me wonder how a high end cabinet saw would live up to this kind of scrutiny ... like a Grizzly or even a lesser Steel City. It would be interesting to compare .....

[dusty]

Don't sit back then guys. Get right in the midst of things and make the discussions go where you need them to go. We, all of us, are here for only two two things. One is to contribute where we can and the other is to log off at night having learned something we did not know when we got.

Be constantly aware, however, that not everything works on every one of these machines. They are not only a very wide mixtures of equipments but they have been in the hands of a large number of different users. We don't all treat our equipment the same way.

I will be looking forward to follow on discussions about table alignment or whatever.

[algale]

Closing Comment: I was very disappointed at how few users contributed. I was disappointed because I know that many of you experience this same issue but never said a word.

Sorry, Dusty. I've been less active than usual on the forum lately as I've been consumed with trying to get the Slow Boat done before things freeze over here.

I do find maintenance and alignment issues interesting and I will surely come back to this thread over the winter.

I was using my extension table today on the right side and, once again, used two levels across the main and extension table to get it all coplanar.

I align the extension table using Nick's method but I find there's a lot of slop in my bores on the right side and if I remove and reinsert the extension table it can easily be made to pitch and yaw before the locks are applied and it will not necessarily lock coplanar to the main table if I am not vigilant with the levels.

I do wonder whether inconsistency in the bores from the left and right side contribute to the error.

[dusty]

Closing Comment: I was very disappointed at how few users contributed. I was disappointed because I know that many of you experience this same issue but never said a word.

Sorry, Dusty. I've been less active than usual on the forum lately as I've been consumed with trying to get the Slow Boat done before things freeze over here.

I do find maintenance and alignment issues interesting and I will surely come back to this thread over the winter.

I was using my extension table today on the right side and, once again, used two levels across the main and extension table to get it all coplanar.

I align the extension table using Nick's method but I find there's a lot of slop in my bores on the right side and if I remove and reinsert the extension table it can easily be made to pitch and yaw before the locks are applied and it will not necessarily lock coplanar to the main table if I am not vigilant with the levels.

I do wonder whether inconsistency in the bores from the left and right side contribute to the error.

I seriously doubt that but I have only three sets of bores to judge from. I don't sense any slop in any of mine.

[rjent]

OK, I WILL ask the question.

Let's take a saw like the Grizzly G1000 series table saw.

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To my eye, which I admit is still noob, looks similar to a 520 ProFence system on a Mark V or 7. This unit has less rip capacity but more HP and costs 1500 dollars or so......



Would this "table" live up to one thousandth tolerance like is expected on our machines (I understand you can "align" the extension tables and achieve that, but when swapping them you find they are "off".

Would the grizzly be held to that much of a standard?

Secondly, it this kind of tolerance necessary for woodworking? I work with less tolerance when building a 350 horsepower small block chevy or Ford engine.

I am just amazed that we are even talking these kinds of measurements. Are they necessary?

Trust me, I am not arguing, I am just having to rethink my approach to making wood projects if this kind of tolerance is needed or desirable .....

[JPG]

Unless you intend to move the table extension to the left side, there is no similarity the the left right aux table issue on the SS.

I assume the only thing adjustable is the leg height. Maybe at the other end to match the height of the two tables.

I think the procedure would be similar - straight edge etc..

I think we take alignment too far in these discussions. Getting it as good as possible is a personality trait. The only reason for going the extra mile is that it insures better safety and accuracy and less grumbling when things do not happen as they should because of some picky alignment detail.

FWIW I played with the laser setup to adjust the aux table. Adjusting those 8 nuts etc. will not necessarily result in flat, parallel to the way tubes alignment. The table is quite rigid and those studs and nuts will not alter the shape of the top surface.(at least not the narrow M5 table) In this case the laser merely results it tail chasing! A different sequence of tweaking may be more successful.