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Posted: Thu Apr 11, 2013 4:59 pm
by dusty
JPG40504 wrote:I believe the 'set screw' was never intended initially to be adjusted by the 'customer', but was placed there to be used in production to adjust out any tolerance buildup.
I have successfully adjusted my Goldie to correctly align with a single(or multiple!) extension table at either end with no futzing between. I have not 'documented' that(yet), but it involves aligning the extension table(base) to the quill shaft at both ends of the headstock/tubes. Yes it requires moving tubes 'away from the casting stops'. No I used no dial indicator to judge success, but used two rip fences to determine if they would align to each other regardless of which table they were mounted on or on which end the extension table was mounted. Actually I checked each to a rip fence on the main table. Tis as accurate as 'normal' alignment main table adjustments.
Since the base castings do not have stops for the bench tubes, there is a great potential for the base castings to be skewed which will be reflected in the spt(and therefore extension tables) mount alignment.
i.e. That set screw will essentially affect twist directly, and other alignments only indirectly.[that screw will add twist that will reposition the shaft relative to an spt shaft, but that is not why it is there! - my understanding of that has changed since MickyD had jig saw alignment problem - Bill Mayo had it correct - move the end castings!]
Hopefully the new DT castings will eliminate the possibility of significant 'twist' of the way tubes. That leaves the base/bench tube mounting as a potential culprit.
The left side (headrest) is greater.
Posted: Thu Apr 11, 2013 5:59 pm
by JPG
dusty wrote:The left side (headrest) is greater.
And is it still greater when the single point is pushed down to become two points?
Orrr do I not unnerstan what dimension is different?
Posted: Thu Apr 11, 2013 6:15 pm
by dusty
JPG40504 wrote:And is it still greater when the single point is pushed down to become two points?
Orrr do I not unnerstan what dimension is different?
I don't push it down. I simply lock it in place. Alignment is great so I don't mess with it.
I'll tell you more about all of this when I finish my own dual tilt experiment.
Posted: Thu Apr 11, 2013 6:20 pm
by JPG
dusty wrote:I don't push it down. I simply lock it in place. Alignment is great so I don't mess with it.
I'll tell you more about all of this when I finish my own dual tilt experiment.
When mine 'locks', the tiebar is resting on the casting/setscrew.
Fair nuff.

I hope to share my own results with older hardware(unmodified Goldie) soon.

Posted: Thu Apr 11, 2013 7:10 pm
by joshh
I just watched a sawdust session that describes the screw and adjustment. It begins at about minute 16 of this session
http://www.shopsmithacademy.com/SS_Arch ... gnment.htm
Posted: Thu Apr 11, 2013 7:18 pm
by JPG
Part of the confusion.
Notice the reference to tube twist!!!!
Posted: Thu Apr 11, 2013 7:27 pm
by joshh
This thread makes me glad I am making a double tilt

Posted: Thu Apr 11, 2013 7:30 pm
by JPG
joshh wrote:This thread makes me glad I am making a double tilt

Yeah! Shims are easier than screws!:D
Posted: Thu Apr 11, 2013 8:16 pm
by reible
I have posted shopsmith's information several times on this subject. Right now I can't find those posts containing the document.
Machines below serial number 290367 had to be filed, as in no adjustment screw. Those with numbers above 290367 have the adjustment screw.
This was for such tools as the jig saw, belt sander, bandsaw, and sprayer, all of which had straight legs. In order to align them you adjusted the screw or filed to get a fit.
This was done after the headrest was squared.
I'll scan it in later tonight and please take the time to print it out and keep for reference so when the subject comes up again we are all working off the same page. (Get it? Same page?).
The instructions are not for the dual tilt machines and were made obsolete with later SPT that have the off set tubes.
Ed
spt lateral adjustment for straight tubes
Posted: Thu Apr 11, 2013 11:10 pm
by JPG
[ATTACH]20972[/ATTACH]
[ATTACH]20975[/ATTACH]
Lateral adjustment is accomplished by 'squaring the headrest'.
Notice the word 'slight' relative to the set screw adjusting. Notice the tie bar screws should be loosened. This does indeed adjust the tilt or helix condition of the way tubes.
Notice the info regarding the tie bar seating on the headrest.(both shoulders)
I believe the offset spt mounting tubes were created to eliminate folks having to 'square the headrest' and mess up alignment in the process.
Notice an uneven floor can affect this.
Now this is not addressing the table alignment issue, but does enlighten us as to what moves what and in what direction.
Now how do we adjust for extension table left/right tilt due to headrest being cocked(spt mounting holes not perpendicular to the way tubes / not parallel with the spt holes on the other end)?;)
There are so many things that interact and can cause slight deviation from perfect alignment, that some tolerance of imperfection must be tolerated.
That said, IMHO one can get closer than 'typical' if correct adjustments are made in the correct order.
The waytubes must not twist from end to end - this causes the headstock and main table to rest at different angles as they traverse from end to end. Set screw is the relevant adjustment.
The headrest must be perpendicular to the way tubes so that the spt mounting tubes are equidistant from the headstock axis of rotation and perpendicular to it front to rear. There is no way to adjust the hinge end spt mounting holes other than squaring the casting front to rear to the bench tubes similar to 'squaring the headrest'. We have to assume the rotation axis is parallel to the way tubes.
I added a pdf attachment.