Table Alignment, Mark V

reible · Post by **reible** » Mon Oct 19, 2009 2:39 am

Hi Dusty,

Glad you did this post. I for one have never been a fan of the dial indicator approach to do alignment and I think your approach is yet another good way to get a decent alignment. I think it was Nick that set the benchmark of within .005" and I see no reason that your method can't get someone that close.

Ed

dusty · Post by **dusty** » Mon Oct 19, 2009 8:52 am

reible wrote:Hi Dusty,

Glad you did this post. I for one have never been a fan of the dial indicator approach to do alignment and I think your approach is yet another good way to get a decent alignment. I think it was Nick that set the benchmark of within .005" and I see no reason that your method can't get someone that close.

Ed

Does that mean, I should be looking to receive a set of dial indicators?

Yes, I believe there is a good chance that Nick set the .005" standard and it is quite arbitrary, I am sure. If you need to get to .005", you can. But like many have said, that is much more stringent than the situation demands. However, error is accumulative and if you start by contributing error to your setup, well, who knows just how inaccurate it it going to be when you are done.

JPG · Post by **JPG** » Mon Oct 19, 2009 2:24 pm

dusty wrote:Get yourself a squared block of MDF and just tune up your table by looking for the gaps. Since they don't have to be real tightly spec'd you won't need your feelers, calipers or dial indicators. Send them to me and I'll find a good use for them.

I can't find a virtual box to send those imaginary implements in!:D I only have the calipers(vernier) on that list, and they are borrowed!:rolleyes:

hobbydad · Post by **hobbydad** » Mon Oct 19, 2009 7:36 pm

I have been trying to work on aligning my table, but I did not get very far. When I tried to align the table 90° to the blade, I could get it aligned on one side of the blade, but not the other. It looks to me like the table is bowed down in the center.

[ATTACH]6241[/ATTACH]

[ATTACH]6242[/ATTACH]
Pay no attention to the bowing at the front of the table in this pic. I believe it is an illusion caused by the proximity of the lens to the table. It isn't really THAT bad.

It is also not perfectly flat when I put the straightedge parallel to the miter slots. Will I ever be able to get it aligned, or is it an excercise in futility? I have also had a hard time boring straight holes in drill press mode, and now I am wondering if it was because of the bowed table (fence not perpendicular to the table in the center).

I appreciate any input.

Loren

JPG · Post by **JPG** » Mon Oct 19, 2009 8:08 pm

Boy did this thread take a nasty turn.

That said, have you tried shimming the table under the trunion bolts?

I assume you ARE attempting to set the 0 degree trunion angle stop. i.e. table top at right angle to the top and bottom of the blade.

The table to blade comments in preceding posts to this thread have been relative to making the miter slots parallel to the blade front to rear.

Other than the shimming suggestion above, I do not know of any GOOD way to correct the sway back condition you have pictured. Not so good ways involve 'forming'!:(

dusty · Post by **dusty** » Mon Oct 19, 2009 8:17 pm

hobbydad wrote:I have been trying to work on aligning my table, but I did not get very far. When I tried to align the table 90&#176]6241[/ATTACH]

[ATTACH]6242[/ATTACH]
Pay no attention to the bowing at the front of the table in this pic. I believe it is an illusion caused by the proximity of the lens to the table. It isn't really THAT bad.

It is also not perfectly flat when I put the straightedge parallel to the miter slots. Will I ever be able to get it aligned, or is it an excercise in futility? I have also had a hard time boring straight holes in drill press mode, and now I am wondering if it was because of the bowed table (fence not perpendicular to the table in the center).

I appreciate any input.

Loren

Loren,

Since the Shopsmith tables cast and not milled, the table tops on none of them will be perfectly flat. Now, having said that, yours might be a bit worse than most. You might want to start a quest for a new table.

However, I think that you should still be able to square your table (miter slot) to the blade.

The miter slots in the Shopsmith tables ARE milled and I would bet that if you check yours you will find they are parallel.

At any rate, you should be able to move the table (per the alignment procedure) into a position where the miter slot is parallel to the blade.

Now, it needs to be secured to the trunnion. When you tighten the trunnion bolts, you may pull it back out of alignment.

Yes, it would be very difficult to do accurate drilling on this table. If I needed to use this table for drilling, I would build a table top to sit on top of this table and secure it somehow (a skirt all the way around would be by first thought). Then when aligning to drill, align to the artificial table top and bit.

I'm concerned about the tables useability. The photos may make it look worse than it is. Can you measure the low spot in the table with respect to the rulers edge as shown in the photo.

Are you using a square and straight edge to align or are you using a dial indicator? Either can be used with equal effectivity but by employing slightly different procedures.

hobbydad · Post by **hobbydad** » Mon Oct 19, 2009 9:40 pm

JPG40504 wrote:That said, have you tried shimming the table under the trunion bolts?

I have not tried shimming between the table and trunnion. Are you suggesting that I shim one side of the table so tightening the other side "pulls" the table down and hopefully straightens it some? I will have to stare at it for a while...

I have aligned the miter slots parallel to the blade (or rather found that it was parallel) and was in the process of setting the 0° stop on the trunnion when I found this problem. I am using the square you see in the pics as my straightedge and a combination square for the angles. I don't see myself ever using a dial indicator, because it would just make me crazy.

The distance between the low spot and the ruler's edge is about 1/32". I measured this at the edge of the table insert, as the insert itself sits lower than the table.

I have considered the idea of building a new tabletop for drilling, but then I would not be able to use the fence. I realize that it is not necessary for a drill press, but it is darn handy.

Due to my financial situation, I won't be able to look for a new table in the near future, and I will have to make due with what I have. Should I square one side of the table to the blade and try to use that side of the table as much as I can? Or should I try to reference the entire width of the tabletop when squaring to the blade? I did find that the rail for the fence does not appeared to be bowed like the table.

The only thing I have used the Shopsmith for in table saw mode is dado cuts. I have a standalone table saw for crosscut and rip. I am mainly building small toys for my kids and misc household items - shelves, picture frames, etc.

Thank you for your replies.

Loren

JPG · Post by **JPG** » Mon Oct 19, 2009 11:14 pm

My reply re shimming was to call attention to the fact that the trunion CAN pull the table top out of a flat condition. Considering that the stop for the table in vertical drill press mode is quite solid, but only on one side it may be that excessive pressure in drill press mode has bent the table. If that is so, it should be possible to 'bend it back'(within reasonable limits).

If you are 'really serious' about attempting to correct this, the first step is to remove the table from the trunion. Next determine the flatness with it unmounted. If it is 'warped' judicious application of 'pressure' in a correcting direction at relevent point(s) MAY bring it closer to reasonable flatness.(this is far more difficult than it sounds) In your instance, prop the outer side edges on a thin board and apply pressure to the middle(stand on it???). If it moves, but not enough, increase the thickness of the 'thin board'. Be careful to not introduce a twist(front to rear) while attempting this. Keep in mind that excessive force MAY cause the casting to break:eek: !

After making it 'flat', reassemble it to the trunion, making sure to place shims between the table and the trunion bolt holes so as to NOT pull it out of 'flat'.

heathicus · Post by **heathicus** » Tue Oct 20, 2009 10:47 am

I have a twisted fence on an old jointer and I asked for solutions on the OWWM forum. One suggestion was to counter twist it back into a straight position, heat it up with a torch, then leave it alone for a while (he suggested a week or two) still held in it's "straight" position. Could a similar technique be used here? Press it "flat", heat it up with a torch (while being held flat), then leave it to cool for a while?

JPG · Post by **JPG** » Tue Oct 20, 2009 2:32 pm

heathicus wrote:I have a twisted fence on an old jointer and I asked for solutions on the OWWM forum. One suggestion was to counter twist it back into a straight position, heat it up with a torch, then leave it alone for a while (he suggested a week or two) still held in it's "straight" position. Could a similar technique be used here? Press it "flat", heat it up with a torch (while being held flat), then leave it to cool for a while?

I am surprised it works with cast iron! How hot???? Do not know how a cup warp would be thusly 'fixed'.

Do we have any materials experts aboard?? Please!