Main Table Location In Drill Press Mode

[dusty]

Let it be known that all devices have a failure point.

For several years I was a Qualification Test Engineer for a major defense contractor. It was my job to test new designs and new production models until they failed. The item being tested had to "fail" or the test was not over.

It was actually a fun job; I got a kick out of telling "some of my fellow design engineers" that their project was coming back for further design analysis and correction.

[saminmn]

[quote="keakap"]I would bet my pizza allotment for the next 6 months that the alignment would be (or could be) affected.

For the heck of it: move your ShopSmith a few feet in any direction]
Yes, I am sure I will have extension table alignment issues from time to time. I am in a small shop and have to move the SS to fit in rips or crosscuts of larger workpieces. It is a part of my WW environment.

I am more concerned with getting table's miter slot parallel to blade and would Dust's idea of using way tubes to align table be discernibly affected by an uneven floor? As there are only a few inches from point table hits way tubes and carriage I am guessing it won't. I may try your idea in that I could put one front corner of SS on an 1/8" or 1/4" scrap do the alignment against way tubes then move the scrap to be under the back corner and check the alignment.

[JPG]

Yes, I am sure I will have extension table alignment issues from time to time. I am in a small shop and have to move the SS to fit in rips or crosscuts of larger workpieces. It is a part of my WW environment.

I am more concerned with getting table's miter slot parallel to blade and would Dust's idea of using way tubes to align table be discernibly affected by an uneven floor? As there are only a few inches from point table hits way tubes and carriage I am guessing it won't. I may try your idea in that I could put one front corner of SS on an 1/8" or 1/4" scrap do the alignment against way tubes then move the scrap to be under the back corner and check the alignment.

Consider the direction of 'twisting'. The feet will possibly splay(end to end and front side to rear) and twist about a vertical axis or an axis parallel to the way tubes. The only way this causes way tube movement relative to each other is a twist. That twist will likely not cause the tubes themselves to 'bend'. Using the way tubes as an alignment reference is not likely to be affected by the way tube twist since the point(s) of contact of the table to the way tubes is close to the carriage and table support posts.

The way tube twisting will not cause the trunion pivot points to reposition to outside the plane parallel to the blade face.(big assumption here[trunion pivots are 'normally' in that parallel plane, but if not, their deviation from that plane would be constant through any tube twisting]).

So IMHO it is still a good way to quickly rough in table/blade aslignment and as a quick check. I would still use the miter gauge & rod to 'fine tune'.

However the effect of said splaying etc. is more evident when using the extension tables due to the greater movement of the tables compared to the legs/way tubes. The distances between 'points of interest' are far greater.

I assume the 'cutting twice' description occurs when cross cutting(no rip fence alignment factor). If it occurs only when ripping, the fence is likely the cause.

[saminmn]

Consider the direction of 'twisting'. The feet will possibly splay(end to end and front side to rear) and twist about a vertical axis or an axis parallel to the way tubes. The only way this causes way tube movement relative to each other is a twist. That twist will likely not cause the tubes themselves to 'bend'. Using the way tubes as an alignment reference is not likely to be affected by the way tube twist since the point(s) of contact of the table to the way tubes is close to the carriage and table support posts.
The way tube twisting will not cause the trunion pivot points to reposition to outside the plane parallel to the blade face.(big assumption here[trunion pivots are 'normally' in that parallel plane, but if not, their deviation from that plane would be constant through any tube twisting]).
Yes my thoughts also

So IMHO it is still a good way to quickly rough in table/blade aslignment and as a quick check. I would still use the miter gauge & rod to 'fine tune'.
I liked seeing this way of doing alignment. Got to get a rod. And probably better look for feeler gauge. I will use to check Dusty's suggestion on my Model 500 and impact, if any, of twist as I said I would earlier.

If Dusty's method works adequately, say to tolerance Dusty mentioned, on my machine this time, why wouldn't it always work, i.e. why not just use it?

However the effect of said splaying etc. is more evident when using the extension tables due to the greater movement of the tables compared to the legs/way tubes. The distances between 'points of interest' are far greater.
Agreed
I assume the 'cutting twice' description occurs when cross cutting(no rip fence alignment factor). If it occurs only when ripping, the fence is likely the cause.
Crosscut and rip both, IIRC. So, it is probably just table alignment that is out of whack a little.

Thanks for helping me think on this one....

[keakap]

However the effect of said splaying etc. is more evident when using the extension tables due to the greater movement of the tables compared to the legs/way tubes. The distances between 'points of interest' are far greater.-jpg

Sounds right.
I haven't done it yet, but after reading all this thread I'm convinced that Dusty's method is a winner. I've probably got the worst SS Base or foundation, and floor combo, in the history of the world, so if it works on mine it'll work on anything.
And it sounds so EE-Z.
Which is so important to me, 'cause if I setup perfectly, but then move the SS a foot in any direction, I gotta setup all over again. Bummer. [But I'm finding new and better ways to utilize my bandsaw!]