My Newest Toy

[dusty]

This photo proves nothing because you are not here to see and feel but this is how I have concluded that the Mark V miter slots are parallel to the cast (not milled) edges of the table insert cut out in a Mark V Main Table.

The setup block measures 2" by 3" +-.001.

Photo angle could be better but this is what I have. You just have to trust!

FWIW I have used crocus cloth to smooth the edges of the slots and inserts on all of my tables. Even those that were milled were not without imperfections. I have done the same with the left and right edges on two of my Main Tables and the one extension table to which I occasionally attache a miter track.

That aluminum bar in the miter track was "milled" (using the conical disk sander) to fit snugly in the miter track. I use this a lot to establish a reference edge. It is marked "This Side Up" for good reason. The other edges (top and bottom) are the sorry result of "poor technique".

[BuckeyeDennis]

Use your calipers and measure a precision setup block ten times. Did you consistently get the same numbers (+-.000)? I doubt it.

Yup. I've checked them against a precision 1-2-3 block, and they are dead-nuts (i.e. better than 0.0005") on all three dimensions. They are Mitutoyo calipers from eBay, and I was very pleasantly surprised at that result. I always qualify my instruments, even if brand new.

You actually just seconded the point I was trying to make. Table-insert pocket parallelness to the miter slots should not be assumed -- it should be checked. But it's up to you to decide what tolerance is "good enough".

[dusty]

Use your calipers and measure a precision setup block ten times. Did you consistently get the same numbers (+-.000)? I doubt it.

Yup. I've checked them against a precision 1-2-3 block, and they are dead-nuts (i.e. better than 0.0005") on all three dimensions. They are Mitutoyo calipers from eBay, and I was very pleasantly surprised at that result. I always qualify my instruments, even if brand new.

You actually just seconded the point I was trying to make. Table-insert pocket parallelness to the miter slots should not be assumed -- it should be checked. But it's up to you to decide what tolerance is "good enough".

I am probably guilty of parsing your words but I had assumed nothing when I implied that the surfaces being discussed were parallel. I have verified those dimensions many times and in more than one manner.

[JPG]

Yes once again 'we' have delved into the persnickety details.

That is necessary so as to gain a common understanding of them and how they affect 'accuracy'.

Such consternation over micro deviations from 'perfect' does ignore the fact that this in not a machine shop tool and should not be expected to even approach their accuracy. It is necessary for that understanding though.

If 'we' did not have dial indicators and precision calipers(and 1 2 3 blocks) we would not be discussing those 'imperfections' at all.

None of all that this thread has 'exposed' detracts from the utilitarian usefulness of the idea first presented. It is a new approach and is likely more accurate than the blade/ss tool kit/mitergauge/marking pencil method expoused by the manufacturer.

I do find it interesting to find Dusty on the side of tolerating less than perfection however.

So let's all be practical and keep in mind we be using a 'wood working machine' that cannot be expected to be perfect(the wood sure isn't ).

[dusty]

Yes once again 'we' have delved into the persnickety details.

That is necessary so as to gain a common understanding of them and how they affect 'accuracy'.

Such consternation over micro deviations from 'perfect' does ignore the fact that this in not a machine shop tool and should not be expected to even approach their accuracy. It is necessary for that understanding though.

If 'we' did not have dial indicators and precision calipers(and 1 2 3 blocks) we would not be discussing those 'imperfections' at all.

None of all that this thread has 'exposed' detracts from the utilitarian usefulness of the idea first presented. It is a new approach and is likely more accurate than the blade/ss tool kit/mitergauge/marking pencil method expoused by the manufacturer.

I do find it interesting to find Dusty on the side of tolerating less than perfection however.

So let's all be practical and keep in mind we be using a 'wood working machine' that cannot be expected to be perfect(the wood sure isn't ).

Actually, you do not know where I stand regarding my tolerance for less than perfection. You, as usual, just think you do!

[JPG]

Yes once again 'we' have delved into the persnickety details.

That is necessary so as to gain a common understanding of them and how they affect 'accuracy'.

Such consternation over micro deviations from 'perfect' does ignore the fact that this in not a machine shop tool and should not be expected to even approach their accuracy. It is necessary for that understanding though.

If 'we' did not have dial indicators and precision calipers(and 1 2 3 blocks) we would not be discussing those 'imperfections' at all.

None of all that this thread has 'exposed' detracts from the utilitarian usefulness of the idea first presented. It is a new approach and is likely more accurate than the blade/ss tool kit/mitergauge/marking pencil method expoused by the manufacturer.

I do find it interesting to find Dusty on the side of tolerating less than perfection however.

So let's all be practical and keep in mind we be using a 'wood working machine' that cannot be expected to be perfect(the wood sure isn't ).

Actually, you do not know where I stand regarding my tolerance for less than perfection. You, as usual, just think you do!

As usual you ignore your previous posts when making similar statements about my understanding thee.

Sorry Dusty but from my perspective that is just plain fact.

My 'tolerance' of these outbursts is exceeded.

We have differing perspective on a lot of things, but do share a desire to understand things and try to improve upon them.

[dusty]

Use your calipers and measure a precision setup block ten times. Did you consistently get the same numbers (+-.000)? I doubt it.

Table Insert to Miter Track 005 (Medium).jpg (151.77 KiB) Viewed 10089 times

Table Insert to Miter Track 006 (Medium).jpg (146.8 KiB) Viewed 10089 times

Table Insert to Miter Track 007 (Medium).jpg (135.31 KiB) Viewed 10089 times

Table Insert to Miter Track 008 (Medium).jpg (138.45 KiB) Viewed 10089 times

Table Insert to Miter Track 009 (Medium).jpg (206.58 KiB) Viewed 10089 times

Yup. I've checked them against a precision 1-2-3 block, and they are dead-nuts (i.e. better than 0.0005") on all three dimensions. They are Mitutoyo calipers from eBay, and I was very pleasantly surprised at that result. I always qualify my instruments, even if brand new.

You actually just seconded the point I was trying to make. Table-insert pocket parallelness to the miter slots should not be assumed -- it should be checked. But it's up to you to decide what tolerance is "good enough".

And so I did just that. This is a tool that for some reason I hardly ever use but no more. I really like this.

As for the Table-Insert pocket being parallel to the miter track - well, this is a sample of one and a small sample at that but it was enough to reassure me.

Tolerance level, there is none. Do whatever feels good. For me that will continue to be .005" when working with the Shopsmith.

[dusty]

Flat doesn't cut it necessarily when you do radial only measurements. You would need to do across hatch pattern as well. Even doing this will not show if a mounted disk is perpendicular to the main shaft. The perpendicular is the critical element to using a plate for an instrument of alignment.

Ed

Maybe true, but we are only concerned with the radial flatness because that is what we are using for the table set up. I am assuming that you will use the full diameter of the disk with its center directly at the top of the table for measurements.

There might be a difference of opinion here. If really interested in radial flatness and radial squareness and how this might be utilized when doing a table saw set up - read and study this link for awhile. I have it bookmarked so that I can go back to it now and end.

http://www.taylorhobsonserviceusa.com/u ... reness.pdf

[BuckeyeDennis]

Use your calipers and measure a precision setup block ten times. Did you consistently get the same numbers (+-.000)? I doubt it.

Table Insert to Miter Track 005 (Medium).jpgTable Insert to Miter Track 006 (Medium).jpgTable Insert to Miter Track 007 (Medium).jpgTable Insert to Miter Track 008 (Medium).jpgTable Insert to Miter Track 009 (Medium).jpg
Yup. I've checked them against a precision 1-2-3 block, and they are dead-nuts (i.e. better than 0.0005") on all three dimensions. They are Mitutoyo calipers from eBay, and I was very pleasantly surprised at that result. I always qualify my instruments, even if brand new.

You actually just seconded the point I was trying to make. Table-insert pocket parallelness to the miter slots should not be assumed -- it should be checked. But it's up to you to decide what tolerance is "good enough".

And so I did just that. This is a tool that for some reason I hardly ever use but no more. I really like this.

As for the Table-Insert pocket being parallel to the miter track - well, this is a sample of one and a small sample at that but it was enough to reassure me.

Tolerance level, there is none. Do whatever feels good. For me that will continue to be .005" when working with the Shopsmith.

I think we can now all agree that your table-insert pocket is indeed parallel to the miter slot!

And I'm with you on what constitutes a reasonable tolerance. I've found that my 520 is capable of holding about 0.005", when I use best practices that I learned right here on this forum.

[JPG]

. . .

I think we can now all agree that your table-insert pocket is indeed parallel to the miter slot!

And I'm with you on what constitutes a reasonable tolerance. I've found that my 520 is capable of holding about 0.005", when I use best practices that I learned right here on this forum.

I presume you attained an EE degree without taking a 'Machine Shop Practices' course.

I believe in 'engineer' first, specialty second.

I consider taking that course a necessary stepping stone that I was fortunate enough to have taken(way back then).