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510 orig/current rails

Posted: Sat Apr 01, 2017 1:31 am
by JPG
There has been 'discussion' regarding the original vs current 510 rail ID difference. The OD is the same on both, so the fence mounts the same.

The wall thickness of the two version differs by about 0.023". This creates a cause of mis-matching table top alignment if the two version are mixed in a setup. Add to that the tendency of the current tubes to shift either up or down as the thumb screws are tightened the table alignment is unpredictable.

The 520 eliminated the up/down variation by 'screwing' the tubes from the bottom of the rail onto a precise extrusion surface in the top interior of the rail.

First the original rail. The connecting tube is inserted and the ends are flush.
510 rail orig.jpg
510 rail orig.jpg (258.69 KiB) Viewed 7130 times
Notice the od of the connecting tube is nearly the same as the id of the rail. Look closely at the top gap - the end of the rail has a slight bevel so look for the 'dark void'. They differ by about 0.012". A reasonably tight fit. Not much 'wiggle' room up/down as the jack screws are tightened from one 'side'.

Now the current rail. Again the connecting tube is inserted and the ends are flush.
510 rail current.jpg
510 rail current.jpg (234.7 KiB) Viewed 7130 times
Now there is a considerable gap between the connecting tube and the rail. They differ by about 0.035"(the id of the rail is 0.023" greater than the original rail). The connecting tube will tend to shift either up or down as the jack screw is tightened from the side.

Finally a peek at the two rails butting against each other on a connecting tube. The 'left' rail is the current size. The 'right' rail is an original size.
510 rail both.jpg
510 rail both.jpg (284.73 KiB) Viewed 7130 times
This illustrates the difference since the opposite sides of the rails both are tight to the far side of the connecting tube. However a typical setup would have one rail supporting the connecting tube(tube setting on the 'bottom' of the rail) and the other rail setting on the 'top' of the connecting tube. That would result in less difference between the table tops.

Critical? Depends upon the setup and how persnickity the operator is. However an aggravation and potential cause of a goof if the two version are mixed in a setup.

Finally I believe a mix is actually more predictable than with an all
current' setup. The supporting end of the connecting tube setting on the bottom of one rail and the other rail setting on the top of the connecting tube could vary in 'height' by close to 3X the amount shown in the last pix.

Re: 510 orig/current rails

Posted: Sat Apr 01, 2017 7:52 am
by BuckeyeDennis
Perhaps a cause of the widely varying opinions as to the "goodness" of the 510 rail system?

Re: 510 orig/current rails

Posted: Sat Apr 01, 2017 8:37 am
by dusty
We must start by ensuring or assuming that the table rails are properly installed and oriented.
P3010002.JPG
P3010002.JPG (1.87 MiB) Viewed 7103 times
If this is not done, it makes no difference whether the tubes are straight or of different size.
P3010001.JPG
P3010001.JPG (1.9 MiB) Viewed 7101 times
I accomplish rail alignment using a piece of hardwood (a setup block). With the tables upside down on a flat surface (the reference surface for this procedure) they are coplanar. The top surface of the rails (bottom surface in the pictures) is up off of the workbench by some unspecified amount. That distance is not critical but must be consistent the entire width of the table and from table to table. I have a 14" long piece of hardwood milled to be that setup block. Alignment is then achieved by loosening the rails from the table, properly aligning them and then securing them to the tables

This all done, the tubes will introduce an error that is no greater than the difference between the ID of the rail being used and the OD of the Extension Tube inserted into it.

Re: 510 orig/current rails

Posted: Sat Apr 01, 2017 9:14 am
by Ed in Tampa
JPG wrote:There has been 'discussion' regarding the original vs current 510 rail ID difference. The OD is the same on both, so the fence mounts the same.

The wall thickness of the two version differs by about 0.023". This creates a cause of mis-matching table top alignment if the two version are mixed in a setup. Add to that the tendency of the current tubes to shift either up or down as the thumb screws are tightened the table alignment is unpredictable.

The 520 eliminated the up/down variation by 'screwing' the tubes from the bottom of the rail onto a precise extrusion surface in the top interior of the rail.

First the original rail. The connecting tube is inserted and the ends are flush.
510 rail orig.jpg

Notice the od of the connecting tube is nearly the same as the id of the rail. Look closely at the top gap - the end of the rail has a slight bevel so look for the 'dark void'. They differ by about 0.012". A reasonably tight fit. Not much 'wiggle' room up/down as the jack screws are tightened from one 'side'.

Now the current rail. Again the connecting tube is inserted and the ends are flush.

510 rail current.jpg
Now there is a considerable gap between the connecting tube and the rail. They differ by about 0.035"(the id of the tube is 0.023" less than the original rail). The connecting tube will tend to shift either up or down as the jack screw is tightened from the side.

Finally a peek at the two rails butting against each other on a connecting tube. The 'left' rail is the current size. The 'right' rail is an original size.

510 rail both.jpg
This illustrates the difference since the opposite sides of the rails both are tight to the far side of the connecting tube. However a typical setup would have one rail supporting the connecting tube(tube setting on the 'bottom' of the rail) and the other rail setting on the 'top' of the connecting tube. That would result in less difference between the table tops.

Critical? Depends upon the setup and how persnickity the operator is. However an aggravation and potential cause of a goof if the two version are mixed in a setup.

Finally I believe a mix is actually more predictable than with an all
current' setup. The supporting end of the connecting tube setting on the bottom of one rail and the other rail setting on the top of the connecting tube could vary in 'height' by close to 3X the amount shown in the last pix.

JPG thanks for showing those pictures! They clearly tell the story as to why I hated the 510 setup. The difference in between the fence rail and the connector tube gave my Aux tables nearly a 1/4 in movement in reference to my main table. If I remembered to lift up or push down as I was tightening I could get the table on the same plane. But the minute is forgot the tables would get out of plane. This stopped the fence from smoothly sliding over to the Aux table. Made some cuts of wood have slight bevels and frustrated me to the point I stopped working on the Shopsmith altogether. In fact if the 520 hadn't. Come out I would have sold my Shopsmith by now or converted it back to the 500. I hated the 510 and I believe Shopsmith should stop production of it. Piece of junk in my opinion.

Re: 510 orig/current rails

Posted: Sat Apr 01, 2017 11:21 am
by dusty
Ed in Tampa wrote:
JPG wrote:There has been 'discussion' regarding the original vs current 510 rail ID difference. The OD is the same on both, so the fence mounts the same.

The wall thickness of the two version differs by about 0.023". This creates a cause of mis-matching table top alignment if the two version are mixed in a setup. Add to that the tendency of the current tubes to shift either up or down as the thumb screws are tightened the table alignment is unpredictable.

The 520 eliminated the up/down variation by 'screwing' the tubes from the bottom of the rail onto a precise extrusion surface in the top interior of the rail.

First the original rail. The connecting tube is inserted and the ends are flush.
510 rail orig.jpg

Notice the od of the connecting tube is nearly the same as the id of the rail. Look closely at the top gap - the end of the rail has a slight bevel so look for the 'dark void'. They differ by about 0.012". A reasonably tight fit. Not much 'wiggle' room up/down as the jack screws are tightened from one 'side'.

Now the current rail. Again the connecting tube is inserted and the ends are flush.

510 rail current.jpg
Now there is a considerable gap between the connecting tube and the rail. They differ by about 0.035"(the id of the tube is 0.023" less than the original rail). The connecting tube will tend to shift either up or down as the jack screw is tightened from the side.

Finally a peek at the two rails butting against each other on a connecting tube. The 'left' rail is the current size. The 'right' rail is an original size.

510 rail both.jpg
This illustrates the difference since the opposite sides of the rails both are tight to the far side of the connecting tube. However a typical setup would have one rail supporting the connecting tube(tube setting on the 'bottom' of the rail) and the other rail setting on the 'top' of the connecting tube. That would result in less difference between the table tops.

Critical? Depends upon the setup and how persnickity the operator is. However an aggravation and potential cause of a goof if the two version are mixed in a setup.

Finally I believe a mix is actually more predictable than with an all
current' setup. The supporting end of the connecting tube setting on the bottom of one rail and the other rail setting on the top of the connecting tube could vary in 'height' by close to 3X the amount shown in the last pix.

JPG thanks for showing those pictures! They clearly tell the story as to why I hated the 510 setup. The difference in between the fence rail and the connector tube gave my Aux tables nearly a 1/4 in movement in reference to my main table. If I remembered to lift up or push down as I was tightening I could get the table on the same plane. But the minute is forgot the tables would get out of plane. This stopped the fence from smoothly sliding over to the Aux table. Made some cuts of wood have slight bevels and frustrated me to the point I stopped working on the Shopsmith altogether. In fact if the 520 hadn't. Come out I would have sold my Shopsmith by now or converted it back to the 500. I hated the 510 and I believe Shopsmith should stop production of it. Piece of junk in my opinion.
You jump on this, Ed, because you believe it makes your point when it really does not. If you would do the arithmetic using real numbers (tube and rail IDs and ODs) you would see that the greatest misalignment of tubes would be somewhere between .03125" and .0625". You can add 1/64" to this number if you assume thin walled rails. The 1/4" that you speak of CAN NOT be attributed to 510 tubes and rails.

JPGs photos without measurements are very misleading. They do not, in my opinion, tell the story at all.

I would challenge you to go to the shop and set up your 510 to show what you claim except that I know you do not have a 510 to do it on. I have a 510 and a 520 and I am making real measurements except that I do not have thin walled rails.

Re: 510 orig/current rails

Posted: Sat Apr 01, 2017 5:15 pm
by JPG
Ahh Dusty, the measurements were made, but were included in the text.

It is unfair to EIT since this thread was about the difference and his experience I assume was with the 'current' version which I believe is worse than mixing the two versions.

As for 'adjusting/aligning, it ain't possible on the original version(Unless you know of a way to move tapped holes).

If you want numbers, I will post measurement details.

I realize it is sometimes difficult to see beyond one's personal experience, but that is where greater understanding resides.

I hate this conclusion, but I suspect the id of the 510 rails was increased to minimize bent tubes jamming in the rails.

Re: 510 orig/current rails

Posted: Sat Apr 01, 2017 6:35 pm
by dusty
JPG wrote:Ahh Dusty, the measurements were made, but were included in the text.

It is unfair to EIT since this thread was about the difference and his experience I assume was with the 'current' version which I believe is worse than mixing the two versions.

As for 'adjusting/aligning, it ain't possible on the original version(Unless you know of a way to move tapped holes).

If you want numbers, I will post measurement details.

I realize it is sometimes difficult to see beyond one's personal experience, but that is where greater understanding resides.

I hate this conclusion, but I suspect the id of the 510 rails was increased to minimize bent tubes jamming in the rails.
You gotta be kiddin!

As for more measurements or restated measurements ... not worth your time.

Re: 510 orig/current rails

Posted: Sat Apr 01, 2017 6:46 pm
by JPG
dusty wrote:
JPG wrote:Ahh Dusty, the measurements were made, but were included in the text.

It is unfair to EIT since this thread was about the difference and his experience I assume was with the 'current' version which I believe is worse than mixing the two versions.

As for 'adjusting/aligning, it ain't possible on the original version(Unless you know of a way to move tapped holes).

If you want numbers, I will post measurement details.

I realize it is sometimes difficult to see beyond one's personal experience, but that is where greater understanding resides.

I hate this conclusion, but I suspect the id of the 510 rails was increased to minimize bent tubes jamming in the rails.
You gotta be kiddin!

As for more measurements or restated measurements ... not worth your time.
No I ain't kidding. Are you 'serious'?

If anyone else cares about the dimensions just tell me.

FWIW I agree EIT's 1/4" does not seem realistic.

Re: 510 orig/current rails

Posted: Sat Apr 01, 2017 9:33 pm
by Ed in Tampa
JPG wrote:
dusty wrote:
JPG wrote:Ahh Dusty, the measurements were made, but were included in the text.

It is unfair to EIT since this thread was about the difference and his experience I assume was with the 'current' version which I believe is worse than mixing the two versions.

As for 'adjusting/aligning, it ain't possible on the original version(Unless you know of a way to move tapped holes).

If you want numbers, I will post measurement details.

I realize it is sometimes difficult to see beyond one's personal experience, but that is where greater understanding resides.

I hate this conclusion, but I suspect the id of the 510 rails was increased to minimize bent tubes jamming in the rails.
You gotta be kiddin!

As for more measurements or restated measurements ... not worth your time.
No I ain't kidding. Are you 'serious'?

If anyone else cares about the dimensions just tell me.

FWIW I agree EIT's 1/4" does not seem realistic.

I really do not know if it was 1/64 or 1/4 of an inch what I know is that was enough to snag the fence each time it slide past the joint and the lousy engineering totally ticked me off.
I hated the 510 and would never own one again.
Dusty you can tell me I am wrong but let me say I would not take a 510 if it was given to me.

Re: 510 orig/current rails

Posted: Sat Apr 01, 2017 9:46 pm
by JPG
A little over 1/16" makes sense.

However with a longer span between the tables and cocked tubes, that would be larger.