Shopsmith Forums

My 520 extension table has never been properly aligned to the main table since I got it from the previous owner, with the right rear corner too low and the left rear corner too high. I had tried following my owner's manual technique and found that each adjustment I made threw off the prior one.

Today I tried something new which worked for me. Here's what I did:

1. Loosen the 4 lower nuts on the extension table's dog bone a good 1/4 inch. Bring the main table up against the extension table until the bosses just kiss and as close to the same level as possible (when bringing the main table against the extension be careful not to push so hard against the extension table as to take all the play out of the table and the dog bone. You want to be able to move the table around on its dog bone.)

2. Slightly loosen the nuts that hold the front and rear fence extrusions to the extension table until you can move those extrusions by hand.

3. Insert a connector tube through the front and rear fence extrusions of the main table and into the loosened front and rear fence extrusions of the extension table. Make sure the hump is oriented up on both tubes (if you've watched Nick's sawdust session on the alignment of the extension table, you know the tubes may not be perfectly flat; it is a good idea to mark the high side of each tube and always insert it with the high side up).

4. Tighten the thumb screws underneath the front and rear fences of the main table (securing the tubes inside the main table fence extrusions). Now tighten the thumb screws underneath the extension table's fronts and rear fence extrusions. The extrusions on the extension table are now aligned to the extrusions of the main table. NOTE: DO NOT tighten the nuts that hold the fence extrusions to the extension table yet. This allows you to align the extension table surface to the main table surface.

5. Level the extension table surface to the main table by adjusting the 4 upper nuts on the dog bone. This is much easier to do because the extension table's front to back movement is entirely constrained by the connector tubes running through fence extrusions. Once the extension table surface is level to the main table surface, gradually tighten the lower nuts on the dog bone, moving from nut. Recheck to make sure the table did not move while tightening these nuts.

6. Last but not least, tighten the nuts that secure the front and rear fence extrusions to the extension table.

Yer done!

Al

[quote="algale"]My 520 extension table has never been properly aligned to the main table since I got it from the previous owner, with the right rear corner too low and the left rear corner too high. I had tried following my owner's manual technique and found that each adjustment I made threw off the prior one.

Today I tried something new which worked for me. Here's what I did:

1. Loosen the 4 lower nuts on the extension table's dog bone a good 1/4 inch. Bring the main table up against the extension table until the bosses just kiss and as close to the same level as possible (when bringing the main table against the extension be careful not to push so hard against the extension table as to take all the play out of the table and the dog bone. You want to be able to move the table around on its dog bone.)

2. Slightly loosen the nuts that hold the front and rear fence extrusions to the extension table until you can move those extrusions by hand.

3. Insert a connector tube through the front and rear fence extrusions of the main table and into the loosened front and rear fence extrusions of the extension table. Make sure the hump is oriented up on both tubes (if you've watched Nick's sawdust session on the alignment of the extension table, you know the tubes may not be perfectly flat]
You have described a procedure that is pretty close to what I have done. We differ in the I do not loosen the front and rear rails. They were installed using still a differe nt procedure to make certain that ALL RAILS ON A GIVEN MACHINE are adjusted the same (with respect to the table surface).

If not already there, I install tubes in the Main Table and secure them in place. This makes the Main Table (with extension tubes) the reference surface.

I got the cart before the horse.

During this time, the extension table has been installed LOOSELY on the dog bone and the dog bon is adjusted to roughly where I want it.

Now I secure the extension table rails to the extension tubes. The table is still loose on the dog bone.

Using a long level or a known straight edge clamped to the main table, I clamp the extension table to that same level (pair of levels front and back works best).

Now I secure the dog bone to the extension table and we are done.

Same method, slightly different procedure.

Now, here is the challenge. Dismount that extension table and relocate it to the other end of the machine. Don't change depth of cut (carriage height). Just move headstock and carriage to the other end as near as possible to the previously adjusted extension table.

Install extension tubes and scratch your head.

No need to report back here unless you want to gloat. I doubt that the extension table will align satisfactorily. If it does - don't ever move your Mark V. It is in the ONLY PERFECT LOCATION.

My way of doing extension table alignment is posted here somewhere... it is different but the end product is what counts.

To that end I have to agree with Dusty that the front rails have a set place and that is done with the gauge blocks supplied. That needs to be done before any other adjustments and should not vary. With your method in mind your first test will be adding a floating table then attempting to fix its alignment to the extension table which is no doubt now mis-adjusted. A slippery slope.

I expect there are 50 ways to do these things, you just have to do what works for you in the end. But do keep the shopsmith instructions in mind.

Ed

Be glad for the double nuts. Shimming is a pita!;)

Yes I know studs and double nut conversion is possible.


I have to disagree with Nick's session re aligning the table to the left side.

IMHO the only satisfactory solution is to have a separate table for each end.

dusty wrote:You have described a procedure that is pretty close to what I have done. We differ in the I do not loosen the front and rear rails. They were installed using still a differe nt procedure to make certain that ALL RAILS ON A GIVEN MACHINE are adjusted the same (with respect to the table surface).

If not already there, I install tubes in the Main Table and secure them in place. This makes the Main Table (with extension tubes) the reference surface.

I got the cart before the horse.

During this time, the extension table has been installed LOOSELY on the dog bone and the dog bon is adjusted to roughly where I want it.

Now I secure the extension table rails to the extension tubes. The table is still loose on the dog bone.

Using a long level or a known straight edge clamped to the main table, I clamp the extension table to that same level (pair of levels front and back works best).

Now I secure the dog bone to the extension table and we are done.

Same method, slightly different procedure.

Now, here is the challenge. Dismount that extension table and relocate it to the other end of the machine. Don't change depth of cut (carriage height). Just move headstock and carriage to the other end as near as possible to the previously adjusted extension table.

Install extension tubes and scratch your head.

No need to report back here unless you want to gloat. I doubt that the extension table will align satisfactorily. If it does - don't ever move your Mark V. It is in the ONLY PERFECT LOCATION.

I knew you would ask.... No gloat here. It is close -- close enough that the extension tube will go in the extension table's front fence extrusion pretty much dead on but slight persuasion is needed on the tube to get it into the rear fence extrusion. I take it from your comments that Nick's magic way tube leveling screw trick from the sawdust session has not solved this issue in the real world for you? I checked my way tubes with a Wixey (Beal Tilt Box actually) and got a 0.35 degree variance side to side, which could be the culprit but I did not try to adjust it to see what difference it made.

Meanwhile, while chasing alignment can be fun, I am actually working on a project that will determine for me whether I get rid of my contractor's saw and rely exclusive on the Shopsmith.

Today's test involved making bevel cuts on the side and end panels of a box that will be 12 inches x 20 inches. I am happy to report (probably to nobody's surprise on this forum) that the Shopsmith gave excellent results using nothing more than a standard miter gauge (that pistol grip is fantastic by the way) with a shop made fence extension.

After cutting the panels to approximate length I set the table to 45 degrees (I double checked the scale on the table with my Beal Tilt Box). Wary of up-hill cut-offs becoming projectiles, I gradually snuck up on my mark, taking small cuts no wider than the blade's kerf. The hardest part of this cut is that the panels are too wide, at 12 inches, to keep the miter gauge's head on the table at the start of the cut, so you need to apply firm pressure to the table, the gauge and the workpiece while pushing the cut through. By the time I realized that I should have turned the gauge around to make the cut easier on myself, I was already done. I dry assembled the box's sides using a little blue painter's tape and the miters look quite good.

Long story short, this machine is clearly capable of giving results in table saw mode that are very accurate. The contractor saw is looking scared and lonely.

reible wrote:My way of doing extension table alignment is posted here somewhere... it is different but the end product is what counts.

To that end I have to agree with Dusty that the front rails have a set place and that is done with the gauge blocks supplied. That needs to be done before any other adjustments and should not vary. With your method in mind your first test will be adding a floating table then attempting to fix its alignment to the extension table which is no doubt now mis-adjusted. A slippery slope.

I expect there are 50 ways to do these things, you just have to do what works for you in the end. But do keep the shopsmith instructions in mind.

Ed

I have a nearly permanent solution for that problem, Ed and it does not utilize an extension table aligned for each end of the Mark V. In fact, it doesn't involve a second extension table.

It is rapidly becoming hazardous for me to be moving that jointer so I don't unless I absolutely must. The jointer is now installed at the left end of the Mark V in a nearly permanent assignment there. No left end extension table required.

algale wrote:I knew you would ask.... No gloat here. It is close -- close enough that the extension tube will go in the extension table's front fence extrusion pretty much dead on but slight persuasion is needed on the tube to get it into the rear fence extrusion. I take it from your comments that Nick's magic way tube leveling screw trick from the sawdust session has not solved this issue in the real world for you? I checked my way tubes with a Wixey (Beal Tilt Box actually) and got a 0.35 degree variance side to side, which could be the culprit but I did not try to adjust it to see what difference it made.

Meanwhile, while chasing alignment can be fun, I am actually working on a project that will determine for me whether I get rid of my contractor's saw and rely exclusive on the Shopsmith.

Today's test involved making bevel cuts on the side and end panels of a box that will be 12 inches x 20 inches. I am happy to report (probably to nobody's surprise on this forum) that the Shopsmith gave excellent results using nothing more than a standard miter gauge (that pistol grip is fantastic by the way) with a shop made fence extension.

After cutting the panels to approximate length I set the table to 45 degrees (I double checked the scale on the table with my Beal Tilt Box). Wary of up-hill cut-offs becoming projectiles, I gradually snuck up on my mark, taking small cuts no wider than the blade's kerf. The hardest part of this cut is that the panels are too wide, at 12 inches, to keep the miter gauge's head on the table at the start of the cut, so you need to apply firm pressure to the table, the gauge and the workpiece while pushing the cut through. By the time I realized that I should have turned the gauge around to make the cut easier on myself, I was already done. I dry assembled the box's sides using a little blue painter's tape and the miters look quite good.

Long story short, this machine is clearly capable of giving results in table saw mode that are very accurate. The contractor saw is looking scared and lonely.

The end casting is the culprit. Those spt mount holes must be identical to the orientation of those on the opposite end relative to the way/bench tubes. An unlikely circumstance and a difficult thing to change or determine.

Just stand at the left end of your machine facing the headstock. Unlock the headrest handle and and lift that end to about belly high. Grasping both sides of the tie bar (one end in each hand) give a little twisting motion and note what happens. Very little force is required and the way tubes are no longer in proper orientation to one another.

If you doubt this, ask someone to move the headstock or carriage back and forth on the ways while you have that twisting force applied. They will be more difficult to slide.

If your carriage and/or headstock do not slide smoothing, this could be one of the reasons. The tubes are mis-oriented even when locked in place. Slightly bent tubes will cause the same problem.

dusty wrote:Just stand at the left end of your machine facing the headstock. Unlock the headrest handle and and lift that end to about belly high. Grasping both sides of the tie bar (one end in each hand) give a little twisting motion and note what happens. Very little force is required and the way tubes are no longer in proper orientation to one another.

If you doubt this, ask someone to move the headstock or carriage back and forth on the ways while you have that twisting force applied. They will be more difficult to slide.

If your carriage and/or headstock do not slide smoothing, this could be one of the reasons. The tubes are mis-oriented even when locked in place. Slightly bent tubes will cause the same problem.

This is where that adjustment screw comes to bear! I will not belabor the point, but it is the twist that Dusty has described that IMHO the screw is intended to correct. It is there for that reason, and only that reason! The 4 tubes need to be parallel!!!!

[quote="JPG40504"]Be glad for the double nuts. Shimming is a pita!]

Red,

I agree totally with a separate table for each end. I made that addition several years ago. Dusty's idea no longer works for me. I have my Joiner on its own stand full time. I do get funny looks when fellows see a table one each end and the twin 520 sitting directly behind my Mark 7 to catch that which is being cut. Jim