Main Table Out of Alignment -need help

[shealyl]

I cannot get my main table in alignment with my saw blade. I am using a dail indicator and the instructions Nick gives on the sawdust session video and cannot get my table closer than 10 thousnads aligned. During alignment it one hole feels like I have less play with it than the others. After reading several post about main table alignment I started finding there are some issues with hole sizes in the trunions. I pulled my trunions off and I have 3 holes 1/2 inch and one hole 3/8 inch in size. I assume this is the root issue of why I cannot bring the table into closer alignment than 10 thousand. Am I on the right track and what do I do now?

[JPG]

I cannot get my main table in alignment with my saw blade. I am using a dail indicator and the instructions Nick gives on the sawdust session video and cannot get my table closer than 10 thousnads aligned. During alignment it one hole feels like I have less play with it than the others. After reading several post about main table alignment I started finding there are some issues with hole sizes in the trunions. I pulled my trunions off and I have 3 holes 1/2 inch and one hole 3/8 inch in size. I assume this is the root issue of why I cannot bring the table into closer alignment than 10 thousand. Am I on the right track and what do I do now?

Drill the 3/8" hole out to 13/32 and start over. That should give you 15/1000 motion in that hole.

There are differing 'opinions' regarding whether that was intentional or not. I think it was, but is no longer done. I do not recommend increasing the hole to 1/2" as that gives too much range and can lead to other alignment issues.

Dusty will probably have comments on this. I believe he now wishes he had not drilled his out. He also has a good method for 'quick' aligning(a good starting point).

BTW 0.010- is really not all that bad!(IMHO)(less than 0.1°)

[reible]

I have several tables with factory holes all being the same. I had one table with the 3 and 1. The table was off a earlier 500 to 510 upgrade.

That 3 and 1 table was always hard to align, but not impossible. I re-drilled mine and have been happy with the results. You might want to check with shopsmith as for a time they were replacing the part for free, or maybe for shipping, I forget.

I felt confident enough to re-drill mine but I believe at least one member had an accident while doing his.... safety first.

We, that is me and the mouse I have in my pocket always go for .005". I have been hitting about .003" and I don't use the gauge to make the adjustments. I use the old methods and then check when I'm finished with the gauge. But everyone to his or her own....

Ed

[shealyl]

Two good answers thanks. I hope Dusty chimes in. Guess I will call Shopsmith in the morning and ask them. I will post what they say

[algale]

I re-drilled both holes in my rear trunnion to 1/2 inch and have no regrets. Made alignment much easier. I can now get down to 0.002-0.003 within a matter of minutes. You do need to be more aware when you re-align that you are starting with the blade close to being centered in the slot. If you choose to drill, you can lay the tunnion flat on the extension table and drill it out in horizontal mode. Just clamp it down.

[dusty]

The first thing you need to do is decide - how tight do you want to get your alignments. If you want to tinker, and I do mean tinker, you can get down to a couple thousands and you don't have to drill the holes out to get there.

Reible has already given you what I use as the magic number - .005".

It also does not matter which hole you use as your pivot hole. Well, NO, in your case it does. You need to use the small hole, which ever that is, as your pivot hole.

Loosen all four trunnion bolts and then tighten the bolt in the small hole to just a bit more than finger tight. Take a measurement from the blade to the miter track (which ever one and with whatever method you prefer). Move to the opposite side of the blade and take another measurement. Move the table in which ever direction betters that measurement.

If the blade is parallel to the miter tracks (equal separation at all points), the table is aligned.

Repeat this procedure, over and over again, until you have it set where you want it.

Carefully tighten down the bolts (finger tight). Repeat the measurements and correct as necessary. Don't loosen the bolts. Tap with the heal of your hand. You should be trying to move the table only thousandths at this point.

Finally, tighten all the bolts - and you guessed it. CHECK THE MEASUREMENTS AGAIN. REPEAT AS NECESSARY.

There is no secret method. After doing this a few times, you will achieve your personal level of precision as quickly as any of us.

Yes, I have developed an alternate method and I have posted it here on the forum. Actually there are a couple. They all work.

Don't let anyone tell you your Shopsmith will not retain alignment, it will. If you experience problems, after you have completed an alignment, check ALL five locking points. Allowing any one of them to be loose will effect table alignment.

BTW - they must all be locked while you are doing the alignment. Good Luck.:):)

This must be done well in order to "Make Sawdust Safely".

PATIENCE, Grasshopper

[shealyl]

Dusty, I am using the method you describe and the closets I can achieve to paralllel with the miter track is 10-12 thousands. I alwasy end up with wanting to move the part of the main table with the small hole those last .005 to .008 and it just dosent have the room to move.

When you mention ALL 5 locking points, please help me out, are these the 5 points you refer to: Lock the power head to the main rails, lock the table carriage to the main rails, lock the blade to the spindle, lock the spindle so it doesnt move in and out, and lock the table top so it does not tilit. If so I am locking all 5.

I will try again with your comments and some other tips I picked up reading the forum but I am not confident that I can bring the alignment in less than .010. and I would prefer to get it down to at least .005

[dusty]

Dusty, I am using the method you describe and the closets I can achieve to paralllel with the miter track is 10-12 thousands. I alwasy end up with wanting to move the part of the main table with the small hole those last .005 to .008 and it just dosent have the room to move.

When you mention ALL 5 locking points, please help me out, are these the 5 points you refer to: Lock the power head to the main rails, lock the table carriage to the main rails, lock the blade to the spindle, lock the spindle so it doesnt move in and out, and lock the table top so it does not tilit. If so I am locking all 5.

I will try again with your comments and some other tips I picked up reading the forum but I am not confident that I can bring the alignment in less than .010. and I would prefer to get it down to at least .005

There is no doubt that your table can be adjusted to something closer. I say that simply because the table moves in all directions and therefore there is no limitation as to how close to dead on it can be positioned.

Which hole is the smallest? I ask only to know. It really makes no difference except in how we talk about doing what must be done. I hope it is the rear/left because that is how I do the alignment.

If it is the rear left, I would start by measuring the offset (blade to t-track) at the outfeed side (rear) of the blade.

With that measurement, I then move to the infeed edge of the blade to make the next measurement and adjust as required.

Then back to the outfeed side, then to the infeed, and back again. This procedure gets repeated until you are very close to whatever measurement you are going to accept.

After I get "close" I tighten the trunnion bolts finger tight. This simply necessitates some force to change table position.

One other suggestion: Make sure that the miter slots are parallel. I have never known them not to be but if they were not, it could make alignment difficult.

I use the left and right miter slots interchangeably. It should have no effect on your results.

Side thought: Just in case we have to go to an alternate method. How do you square your miter gauge. I rely on a Wixey and use the miter bar as reference. With the miter gauge "dead on", the blade should be square to the face of the miter fence. That deviation can be measured with feeler gauges. With a square tight against the face of the miter gauge, the other side of the square should be parallel to the blade. Here is where you use a feeler gauge.

[JPG]

. . .
When you mention ALL 5 locking points, please help me out, are these the 5 points you refer to: Lock the power head to the main rails, lock the table carriage to the main rails, lock the blade to the spindle, lock the spindle so it doesnt move in and out, and lock the table top so it does not tilit. If so I am locking all 5.

. . .

When securing the 'five', the table height is included. The spindle/arbor is always assumed.

So you have expanded the 'list' to 6!;)

[shealyl]

Dusty....

Yes my small hoel is rear left. As for squaring my miter gauge to the blade I use my Starett combination square against the blade and move my miter fence to 90 degrees. I use a Wixley to ensure table is 90 degrees to the blade. Never thought of using the Wixley for the miter fence, but thats a good tip.