Today in the shop (table alignment with master plate)

[reible]

I've been using this for a couple of years now and while I am not totally sure how well it will work for everyone I'm going to put it out here so you can comment and if you have a master plate give it a try and see how it works for you.

First let me say that I've been at better then .005" using this method. Now this is dependent on a lot of factors so that is why I want to make it clear that you can do this and get better then accepted tolerances. I've been using a dial indicator to check alignment after doing this and for the most part I'm all but total convinced that I can stop doing it but.........

Step one is to mount a master plate on the main shaft using a 5/8" universal arbor. The master plate is too thick to use a saw arbor I believe while it has been a couple of years since I tried it but I think that was the case.

As a simple mater of doing what you normal do make sure the head stock is lock on the tubes and the quill is locked tight.

You can then mount the table and set to table saw position and loosen the necessary screws to allow it to move(before or after you mount it). I like to snug them up finger tight so the table is not squirrelly but can still move. Do this how ever you feel comfortable with.

The following photos are a simulation but should give you an idea of how this works.

Located table with the left miter slot set so the master plate will slide in the miter slot. It will something like this:

IMG_2651sc.jpg (478.44 KiB) Viewed 4614 times

You then can raise the table as shown here:

IMG_2652sc.jpg (493.59 KiB) Viewed 4614 times

The table and carriage can then be moved to the right so the master plate is contacting the left edge of the left miter slot. At this point you will have to decide if you are happy with that location or have to work out how to center the blade in the table like Dusty likes. I personally have not addressed this but might in the future.

As you can see on this adjusted table the plate and slot are tight to each other. If the table is loose it will not likely be so.

IMG_2654sc.jpg (451.28 KiB) Viewed 4614 times

I use clamps from the table to the master plate to force the ends to the miter slot like shown here:

IMG_2655sc.jpg (469.41 KiB) Viewed 4614 times

At this point you have to very carefully tighten the mounting screws as it is still possible to twist things. What ever method you have had success with in the past will work.

When you take off the clamps you can use a feeler gauge to check keeping in mind the plate tolerance and slot tolerance could show up as a few thousands.

At this point you can go to table saw mode with the master plate in the saw slot and using a dial indicator check the slot to plate numbers. I find the shopsmith dial indicator miter bar to be far too loose to get good results even in the best of times........ but you can be the judge of that for yourself. I wedge it to the left at both ends of the master plate for measurements but one day I want to replace the bar with a better system.

If I forgot anything or wasn't clear on how this works please ask. If you have a master plate please give it a try and report back.

BTW my master plate is an older model, the newer ones are blue I believe and I have no idea if any other changes have been made. I found mine to be pretty precise when compared to other flat surfaces I have.

Ed

[dusty]

Ed, now that I have had some time to play with my setup plate I can really see the value in the Master Plate. You have mentioned it before and I gave it some thought but not enough to go buy one. I can see from your post here that it will work as well as anything I have been using and maybe even better.

The only thing that the Master Plate fails to provider (for me) is the centering of the blade in the table cut out and alignment of the table to the drill line.

Based on other comments from the other current thread discussing this subject and my most recent experimentation with my setup plate, I drew up the following Sketchup to show where I am going with this. I aligned two tables in about 10 minutes using this approach.

Table Setup witha Thin Kerf.png (22.31 KiB) Viewed 4608 times

The dimensions given here will center a 3/32" thin kerf blade in the Mark V Main Table cutout. The quill most be fully retracted and locked and of course all other locks secured. Mount the thin kerf blade and arbor, loosen all four trunnion bolts and then push the table so that the jig (installed in the right hand miter slot) snugly contacts the blade. Tighten the trunnion bolts without allowing the Main Table to change positions. Check visually to ascertain the desired snug fit and you are done. Less than 10 minutes.

The overall width of the jig (4 3/16") is critical. The best way to achieve it, I believe is by attaching the runner (it is really not a runner but rather a stop) to the birch plywood. With the runner in the right hand miter slot, cut the jig to a little over the 4 3/16" dimension and then using the conical disk sander, sneak up on the 4 3/16" by utilizing the quill.

[Gene Howe]

That looks like even I could get precise alignments. But, from whence does it come?

[dusty]

That looks like even I could get precise alignments. But, from whence does it come?

Alignment is no more or less accurate than any of the many other proposed methods but is certainly much quicker and I believe easier. This will be my method for awhile with the sole exception that I will use the setup plate and a jig with a slightly different dimension (4 11/64") to facilitate the 1/8" plate.

[Gene Howe]

That looks like even I could get precise alignments. But, from whence does it come?

I FOUND IT!

[sehast]

I've been using this for a couple of years now and while I am not totally sure how well it will work for everyone I'm going to put it out here so you can comment and if you have a master plate give it a try and see how it works for you.

First let me say that I've been at better then .005" using this method. Now this is dependent on a lot of factors so that is why I want to make it clear that you can do this and get better then accepted tolerances. I've been using a dial indicator to check alignment after doing this and for the most part I'm all but total convinced that I can stop doing it but.........

Step one is to mount a master plate on the main shaft using a 5/8" universal arbor. The master plate is too thick to use a saw arbor I believe while it has been a couple of years since I tried it but I think that was the case.

As a simple mater of doing what you normal do make sure the head stock is lock on the tubes and the quill is locked tight.

You can then mount the table and set to table saw position and loosen the necessary screws to allow it to move(before or after you mount it). I like to snug them up finger tight so the table is not squirrelly but can still move. Do this how ever you feel comfortable with.

The following photos are a simulation but should give you an idea of how this works.

Located table with the left miter slot set so the master plate will slide in the miter slot. It will something like this:

IMG_2651sc.jpg

You then can raise the table as shown here:

IMG_2652sc.jpg

The table and carriage can then be moved to the right so the master plate is contacting the left edge of the left miter slot. At this point you will have to decide if you are happy with that location or have to work out how to center the blade in the table like Dusty likes. I personally have not addressed this but might in the future.

As you can see on this adjusted table the plate and slot are tight to each other. If the table is loose it will not likely be so.

IMG_2654sc.jpg

I use clamps from the table to the master plate to force the ends to the miter slot like shown here:

IMG_2655sc.jpg

At this point you have to very carefully tighten the mounting screws as it is still possible to twist things. What ever method you have had success with in the past will work.

When you take off the clamps you can use a feeler gauge to check keeping in mind the plate tolerance and slot tolerance could show up as a few thousands.

At this point you can go to table saw mode with the master plate in the saw slot and using a dial indicator check the slot to plate numbers. I find the shopsmith dial indicator miter bar to be far too loose to get good results even in the best of times........ but you can be the judge of that for yourself. I wedge it to the left at both ends of the master plate for measurements but one day I want to replace the bar with a better system.

If I forgot anything or wasn't clear on how this works please ask. If you have a master plate please give it a try and report back.

BTW my master plate is an older model, the newer ones are blue I believe and I have no idea if any other changes have been made. I found mine to be pretty precise when compared to other flat surfaces I have.

Ed

This method of using the master plate is as good or better (IMO) than most of the other alignment methods that have been discussed here recently but none of them account for run out errors that can occur in the arbor, disk or blade or plate. They basically assume zero run out by ignoring it which might be a plausible assumption but you won’t know for sure until you measure it. It can be measured by moving the main table to the right of the plate and adjusting it so it is the same height as the middle of the arbor bolt. Then place a mark on front side of the plate close to the edge. Use a dial indicator in the left miter slot of the table to measure the distance to the mark on the plate. Rotate the plate 180 degrees so the mark is now at the back side of the table and then without moving the dial indicator, repeat the measurement from the miter slot to a point on the plate which is now 180 degrees from the mark. For a disk you can simply rotate the disk and note the dial indicator minimum and maximum readings throughout a full 360 degrees of rotation. If there is no difference in the two plate measurements or if the min and max disk readings are the same, then the assumption of zero run out is valid. If there is a difference then the table could be set with that much error in it.

At the end of the day what you want is for the kerf made by the saw blade to be parallel to the miter slots not the blade or disk at some arbitrary position. That is the reason I prefer the single tooth saw blade alignment technique. By setting the distance of a marked tooth to the miter slot to be the same at both the front and the back of the table when the blade is rotated 180 degrees effectively compensates for the run out and ensures the kerf is parallel to the miter slot. Even if a different saw blade is used with a different run out, the table will still be set parallel to the kerf. Using a 12” sanding disk with a mark on its edge more easily accomplishes the same thing but in both cases to get a full 180 degrees of travel the blade or disk need to be to the left of the table, not in the insert. You can probably measure with the blade in the table insert not getting a full 180 degrees of rotation and still get good alignment. I am just a little anal sometimes.

One simple way to check to see if the table is aligned properly is to take a piece of straight stock about 1“wide by 1” thick and set your miter gauge for a 90 degree cut. First use the right miter slot. Set the table all the way down to a maximum depth of cut. Firmly hold the stock in the miter gauge as it passes from the front to the back of the blade. If you hear a zing as the stock passes the back side of the blade then you have the blade too far to the right. If no zing is heard then repeat the cut, this time in the left miter slot. If a zing is heard here the blade is too far left. No zings on either side indicate it is in good (enough for me) alignment.

[Gene Howe]

I JUST GOT IT! The brown truck guys just dropped it off.
I'm definitely looking forward to an alignment party.
Thanks for the heads up, Ed.

[JPG]

I JUST GOT IT! The brown truck guys just dropped it off.
I'm definitely looking forward to an alignment party.
Thanks for the heads up, Ed.

I hope they did not REALLY drop it!

[Gene Howe]

I JUST GOT IT! The brown truck guys just dropped it off.
I'm definitely looking forward to an alignment party.
Thanks for the heads up, Ed.

I hope they did not REALLY drop it!

Oh boy, now I get to use my straight edge, too.
I have three different machines to use the Master Plate on.
This is going to be fun. Already thinking of other applications for it's properties.