What's wrong with my table?

[Meng88]

Whenever I need outfeed support, I do the old school way of using the extension table on it's base mounted to the Mark V backward, then using a rail to attach another extension table. Like in this video (https://www.youtube.com/watch?v=mg9JazGDRag). But every time I do it, I notice that something isn't right. I have my the table that is on the base aligned to the main table perfectly. But when I turn it around backward, it is sloped downward. All of this tells me that the main table is somehow not aligned right. But I don't know of any adjustments for the front to back slope (see photos of table mounted regular and backward). I've looked through my alignment dvds and can't find anything.

So maybe an internet expert will know what is wrong here.

Disclaimer: Don't judge my garage shop mess.

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[JPG]

Get out thy trusty spirit level.

First check the way tubes both side to side and front to rear. If they are not level both directions, then shim the legs so they are.

Now check the saw blade(or sanding disk). The face should be plumb.

Then check the main table to be level(perpendicular to the blade/disc). Level both left to right and in/out.

And then, check the aux table to match the main tavble both left to right and in/out.

If all that leveling is correct your 'problem' should not exist.


I notice one of the studs on the aux table extends out from the nut much further than the other three.

[Meng88]

First check the way tubes both side to side and front to rear. If they are not level both directions, then shim the legs so they are.

Ok, so the top way tubes definitely seem to be what is out of alignment. But I have no idea how to adjust this. The "back" (when standing as if operating table saw) is higher than the front. But it doesn't seem possible to adjust this. On the left side that lifts there is a screw on the Mark V legs that appears to be for this adjustment (see photo), but when the way tubes are down in table saw mode it doesn't even touch this screw (another photo). So I don't know how to get the backside of the way tubes lower, and there isn't a similar adjustment for me to raise the front.

I notice one of the studs on the aux table extends out from the nut much further than the other three.

Just seeing this, but I think what you are actually seeing is the nut that I had apparently forgotten to tighten after adjusting.

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[DLB]

The 'big set screw' is both upside down and out of adjustment, but evidently not causing the problem. IIWM I'd next check the lower bench tubes to see if they are similarly out of level. Assuming they are level front to back, I'd shift my focus to the Base end of the machine. When checking pairs of tubes for level front to back, it is helpful to check near both ends.

- David

[Meng88]

The 'big set screw' is both upside down and out of adjustment, but evidently not causing the problem. IIWM I'd next check the lower bench tubes to see if they are similarly out of level. Assuming they are level front to back, I'd shift my focus to the Base end of the machine. When checking pairs of tubes for level front to back, it is helpful to check near both ends.

- David

Oh yeah, didn’t mention that I have checked the lower tubes and they are level. A couple other things I’ve also tested since the post:

-wondered if the lift assist might be pushing the back end up. I didn’t think it would, but might as well check. But no. Without the lift assist, it still looks the same.
-tried to shim the front side to see if I could make it level with the back. But this just lifted the back even higher.

I then went to take the motor off to see if the tube might be bent. This is when I found something interesting. When I took the motor off and brought the tubes back down, the back end went all the way down to that set screw. But when I put the motor back in, it wouldn’t go down all the way. So something about the motor on the way tubes it pulling that back up. But this makes zero sense to me, because all of the weight of the motor is between the tubes. So how could it pull the back one up?

But to your suggestion regarding the base side. This was my next step, but I don’t know how to make any adjustments there. Are you aware of any way to do this?

[JPG]

#1 The purpose of that big set screw is to place the way tubes in a non-twisted plane.

So adjusting it to do other things will screw that up.(I do not care if both Nick and Scott say otherwise!!!)

So apparently the way tubes are in a twist. That can be observed by the changing front to rear tilt(off level) as the main table is moved left to right...

To correct the twist loosen the tie bar and the screws retaining the way tubes at the hinge end. This should be able to cause solid resting on the headrest(including the set screw). It should also put the way tubes in a plane parallel to the bench tubes plane. If not all later adjustments will be futile. Retighten all 4 way tube set screws(leave that big un alone).

As for the big screw adjustment, I would only attempt it with a laser level that projects a vertical plane of light from the center of the aux table, over the center of the headstock onto a reversable reference(aux table tube mount with the center between the two mount tubes marked so it can be referenced both orientations. That procedure with subsequent proper alignment of an aux table will make the aux table usable on either end(with proper alignment of the end castings to the way tubes). Yes it ALL needs to be correct!

As for the headstock changing the twist, I surmise tightening the headstock lock will pull the way tubes to a different twist. If they are not twisted to begin with that should not have any effect.


This might take a week(end?) to correct.

[Meng88]

So apparently the way tubes are in a twist. That can be observed by the changing front to rear tilt(off level) as the main table is moved left to right...

To correct the twist loosen the tie bar and the screws retaining the way tubes at the hinge end. This should be able to cause solid resting on the headrest(including the set screw). It should also put the way tubes in a plane parallel to the bench tubes plane. If not all later adjustments will be futile. Retighten all 4 way tube set screws(leave that big un alone).

After messing with it for a few hours tonight, I'm realizing how complex getting this all aligned correctly is. I'm getting REALLY close. But still not exact (but starting to wonder if exact is possible). Because there doesn't seem to be an exact science to this. Unless I'm missing something, here's what I've been doing:

• Loosen headstock and carriage so that they aren't adding any stress to the tubes

• Lift the table since the bolts on one end are under the tie bar

• Loosen all 4 bolts

• Lower it to allow it to settle and have weight on it

• Tighten hinge side

• Carefully lift tie bar side so it doesn't twist

• Tighten tie bar side

Then check all of the tubes to see if they are level. Then realign the extension table that is on the base and turn it around to see if it is also aligned when reversed. Is this all right?

After doing this countless times this evening, it got me wondering if this is how it is done out of the box? I inherited this, so I wasn't the one who bought it. But I can't imagine that it comes assembled. So is this all part of the assembly process when you purchase it? Does shopsmith have directions for this process?

[JPG]

SS has a manufacturing jig to align all the base parts. I assume the way tube assembly is adjusted separately from all the other parts.

Yes it comes assembled from the 'factory'.

No ss does not have a published procedure for this by owners.

To help, maybe removing the headstock until the base is correct. That allows more gentle movement with set screws not completely tightened.

While doing this I would adjust/tighten the tie bar last.

Barely snug the hinge base set screws and allow the way tubes to settle in. Then tighten one hinged base setscrew and recheck, then the second hinged base setscrew. and recheck. Ya tis tedious but gotta eliminate slight slippage until all is tight. Rechecking means level front to reae AND left to right. Oh and a 2x4 to help twist adjustment.

Remember to keep the bench tubes 'level'.

Do not ignore main table tilt zeroing in through all this.

Aux table adjustment can get persnickety real quick.

Do not rush to check the final goal(reversing aux table) until all else is as good as you can get it.

If you have a digital level(wixey ...) use it atop the spirit level so you have a broader base.

As usual accurate measurement thingies(level...)are necessary, but also too precise nit picking will lead thee on a 'merry' chase.

Where are you? 03:30 here!

[edma194]

After doing this countless times this evening, it got me wondering if this is how it is done out of the box? I inherited this, so I wasn't the one who bought it.

In the following thread I documented my wandering journey to build my own double tilt shorty. Right off the bat I found out that I had a right side tilt casting that had the holes for the way tubes bored off center. With shorter way tubes the assembly would barely go together with the way tubes splayed at different angles. You may have a similar situation to deal with.

viewtopic.php?p=304281&hilit=ALIKE#p304281

[chapmanruss]

The one alignment I have not read in this thread is a factory done alignment during assembly. As JPG said the Mark V's are assembled and aligned at the factory. They are shipped without the legs attached. The Main Table is aligned front to rear at the factory but if the Main Table itself has been removed from the front and rear Trunnions at some point they may not have been reinstalled correctly. With the Mark V in Drill Press position (or even laying down in normal position) and the Table at the 90-degree position, use a drill bit in the chuck and check the front to back table alignment with a square. Since this has to be done with the square sitting on a table insert make sure the insert is level to the table's top. This is also a good time to check the 90 degree stops on the table tilt using the drill chuck and bit as shown in the Mark V 520 manual under alignment. The Help Kit Shopsmith sells has a package of parts containing 18 Assorted Shims along with set screws, etc. Leveling the Main Table front to back is one of the uses for those shims.

Since the Extension Table is in alignment when mounted in its normal position but no longer aligned when reversed I suspect the Main Table is not properly aligned front to back.