Schedule a Meeting · Talk to a real woodworker: +1 937-890-5197 · 8:00AM – 4:30PM ET

Slop in the Rails Adversly Effects Alignment

dusty

I don't think so and especially when comparing 510 tubes and rails to those of a 520.

It is raining and cold outside so I took time to sketch the rails and tubes so that I could SEE the slop. I conclude from my sketches (and I was very careful making the measurements) that the "unwanted movement is not greater than 1/16" and even that would be alleviated with proper alignment.

Remember - the table tubes are not reference surfaces. They are there to help stability

Slop ion the Rails.jpg

SteveMaryland

Pictures are worth 1000 words.

520 design is better than 510 but both displace rather than zero out slop because both use setscrews. 510 slop is x-y where 520 confines the slop to x. As the drawing shows.

Setscrews and wedges are inexpensive but imperfect. A collet-chuck design would have been the best way to zero out all radial slop.

dusty

I wonder why you are concerned about whatever slop there is in the Table Rails.

Alignment is in no way dependent upon the Table Tubes If you believe otherwise, please explain.

SteveMaryland

Because I want location repeatability - I want to be able to mount and dismount aux tables so they mount repeatably.

510 nested circular tubes setscrewed in place allow some non-repeatability of tube to tube alignment. The 520 extrusion geometry attempts to remedy this.

Alignment in this case means repeatable co-planarity of all aux table surfaces with the main table, every time aux tables are mounted.

dusty

SteveMaryland wrote Because I want location repeatability - I want to be able to mount and dismount aux tables so they mount repeatably.

510 nested circular tubes setscrewed in place allow some non-repeatability of tube to tube alignment. The 520 extrusion geometry attempts to remedy this.

Alignment in this case means repeatable co-planarity of all aux table surfaces with the main table, every time aux tables are mounted.

OKAY...but I would be very interested in knowing how you would propose this could be done. I obtain table top coplanarity relationshipwith a straight edge across all tables involved after the Main Table height has been set. Unless you believe you can tie the tables together and then adjust table height (depth of cut) I see no other way. Please show me if you have a way.

JPG

The 'issue' of the 510 clamping method(horizontal) is that there is no GUARANTEE the inner connecting tube will vertically align with the mid point of the outer rail tube. The clamping screw CAN cause the inner tube to be slightly displaced vertically(up or down) differently on tables being connected. The torque of the clamping screw essentially guarantees that depending upon the lack of a square end on the screw..

The later 510 version somewhat helped this by making the rails adjustable by bolts through somewhat sloppy holes similar to the attachment of the 520 rails. The early 510 used tapped holes in the table to attach the rails thus providing NO way to adjust. The connecting rail vertical variability remained.

The alignment criteria is a common horizontal plane for ALL connected table tops.

dusty

JPG wrote The 'issue' of the 510 clamping method(horizontal) is that there is no GUARANTEE the inner connecting tube will vertically align with the mid point of the outer rail tube. The clamping screw CAN cause the inner tube to be slightly displaced vertically(up or down) differently on tables being connected. The torque of the clamping screw essentially guarantees that depending upon the lack of a square end on the screw..

The later 510 version somewhat helped this by making the rails adjustable by bolts through somewhat sloppy holes similar to the attachment of the 520 rails. The early 510 used tapped holes in the table to attach the rails thus providing NO way to adjust. The connecting rail vertical variability remained.

The alignment criteria is a common horizontal plane for ALL connected table tops.

Assuming that the 510 Table Tubes are not all in the same horizontal position after being tightened, what adverse effect does that have on table alignment???

dusty

SteveMaryland wrote Pictures are worth 1000 words.

520 design is better than 510 but both displace rather than zero out slop because both use setscrews. 510 slop is x-y where 520 confines the slop to x. As the drawing shows.

Setscrews and wedges are inexpensive but imperfect. A collet-chuck design would have been the best way to zero out all radial slop.

I understand what you are saying but does this have any direct effect on table alignment. I think not.

DLB

In another thread on the same subject, I made the observation (https://forum.shopsmith.com/viewtopic.php?p=305196#p305196) that the 510 system was unlikely to provide the same improvement to main table stability as the 520 when tying the main table to the extension table via connector tubes. Those of us that use this technique do so to maintain alignment of the main table during use, when there is weight or other force on the table that may cause it to deflect. The theory, admittedly unproven, is that slop in the rails (510) adversely effects main table alignment stability compared to less slop (520).

As a 520 user, I also agree with the coplanar argument. I align table height of all tables relative to the extrusions using the 520 alignment jig. Tables are interchangeable among machines. While it has no effect on main table alignment, it is part of system alignment. While I think I could produce acceptable results on a single 510 using a straight edge, I don't think I'd have the interchangeability between 510 systems.

Both of the above are relatively minor concerns. And perhaps add to the unproven concerns that Scott raised in his video regarding table sag and 510 fence alignment of floating tables. I don't currently have a 510 fence, can't really test things, but I see some valid if unproven concerns here.

- David

RFGuy

David,

Thanks and well said. I agree. The whole point of an alignment is to make straight & square cuts with repeatability. To my knowledge there is NO Shopsmith procedure documented for aligning floating tables and this is the crux of the problem IMHO. Based on the other thread and Scott's video it appears that 520 rails eliminate some variability in floating table placement compared to the 510 rails which becomes a problem when the fence is installed for rip cuts on the floating table. Having a perfectly aligned main table is pointless if a floating table is skewed when the rip fence is placed on it because the fence won't be parallel to the blade. How big of an issue this is has to be determined, but it is a difference.

JPG

OK Dusty. When stacking tables horizontally(main-float...-aux) the varying vertical displacement of the connecting tube within the rail tube will result in the table tops varying elevation. Granted that may be small, but it drove Ed in Tampa berserk. The 520 eliminates that by providing a consistant rail to table top dimension by virtue of the gauge(or thy procedure). Also a poster here also helped that by tapped holes in the bottom of the rail tube thus causing screws similar to the 520 to clamp the connecting tube to the top of the rail tube.

One thing I have not highlighted here is the newer version's increased clearance between the connecting tube and the rail tube. That exacerbates the problem.

Keep in mind there are two issues. Vertical top co-planar and rip fence skew.

reible

My own experience is that I did not have the ability to use the fence well when straddled between main and either a floating table or a lesser extent a fixed table.

A bit of back ground. I had used a new from shopsmith 500 for many years. The lure of the 520 was the bigger table and the extension tubes to make it even bigger. I finally purchased the 520 upgrade kit. Shortly after there was a period where the possibility of shopsmith company no longer existing was a real concern at least for me.

I started shopping for a used machine so I would have spare parts if nothing else. I found a basket case 510. I had to put some $$ into it but the low starting price made it a decent deal. The main issue I had was as mentioned, was trying to use the rip fence across the seam of a floating table and the main table. Try as I might I could not resolve this.

For a while I thought I could live with this issue but having a 520 already in use I expected more of the 510 and it just wasn't there. So I did the 510 to 520 upgrade.

For me I would rather have 520 followed by the 500 then the 510. Now it could be getting a used 510 it might have had some previous owner issues that were not apparent but they all went away with the upgrade.

Ed

dusty

JPG wrote
The 'issue' of the 510 clamping method(horizontal) is that . The clamping screw CAN cause the inner tube to be slightly displaced vertically(up or down) differently on tables being connected. The torque of the clamping screw essentially guarantees that depending upon the lack of a square end on the screw..

The later 510 version somewhat helped this by making the rails adjustable by bolts through somewhat sloppy holes similar to the attachment of the 520 rails. The early 510 used tapped holes in the table to attach the rails thus providing NO way to adjust. The connecting rail vertical variability remained.

The alignment criteria is a common horizontal plane for ALL connected table tops.

There is no guarantee but it is highly likely that the Table Tube will rise to the center position inside of the 510 table rail when lateral pressure is applied by the thumbscrew. However, if we are discussing Main and/or Extension Tables - this in NO WAY effects the positioning of the table tops. If the discussion includes floating tables - yes the table tops may change relative position with respect to the table tubes (by an amount of approximately 1/32"). I don't think this would be significant enough to make Ed in Tampa get rid of his 510.

As for pointed (non-square) thumb screws:

510 able Thumbscrews.jpg

Hobbyman2

JMO ,,,,, tossing mud on the wall as they say , once my main table is aligned I slide the main table and carriage to the ext table on both ends of the SS and align the ext tables to the main table , this has all ways proven to be some what reliable for alignment of the ext tables for me ,, any minor adj can be done with the adjusting screws on the fence, not sure if this is a solution to what I am reading . the only time I have needed the fence on a ext table was when I was using the SS as a miter stand . using a flat steel ruler or a pattern to double check the fence should be done on nearly every machine , I have done this on every machine and set up I have used including commercial saws before making a cut and periodically when making multiple pieces , .its also pretty easy to make a pattern out of about anything ,Masonite / scrap cutoffs even a 1x2 with something that slides from end to end and you can clamp in one way or another so you dont have a bunch of stuff laying around ,, anything will work , ya can just toss in to set up the saw and you dont need to worry about checking the numbers every time .JMO

RFGuy

dusty wrote There is no guarantee but it is highly likely that the Table Tube will rise to the center position inside of the 510 table rail when lateral pressure is applied by the thumbscrew. However, if we are discussing Main and/or Extension Tables - this in NO WAY effects the positioning of the table tops. If the discussion includes floating tables - yes the table tops may change relative position with respect to the table tubes (by an amount of approximately 1/32"). I don't think this would be significant enough to make Ed in Tampa get rid of his 510.

As for pointed (non-square) thumb screws:

510 able Thumbscrews.jpg

Dusty,

Thanks. I think you are forgetting about the potential skew of the floating table. What happens if the floating table front is locked in place closer to the main table than the rear lock or vice-versa? I believe this could happen with either the 510 or the 520 table systems, but given the greater variation on the 510 rail it should be worse. Separate from this is what happens when you do lock down the floating table on a 510? On the other thread it was suggested that the thumbscrew might bias the 510 connector tube up/down as it seats, whereas this is not possible on the 520 because it biases it only up and locks it to the rail in a tight fitting channel. Not trying to belabor this discussion, but it seems to me that there is potential for greater variation in floating table position on the 510 and the 520 attempted to fix this. In my opinion they did and the 520 is a definite improvement. Keep in mind Shopsmith repeatedly has stressed how fast the Mark V system is, e.g. with changeovers, etc. Many of us, or at least I, was told that I could install the rip fence on the floating table and go off and make repeatable cuts with it...and do so quickly. Not even talking precision here, but safe, kickback free cuts. After Scott's video and the other thread, I now see why that was a fallacy on the 510 using the floating table. Sure, Shopsmith owners can attempt to assemble multiple tables upside down on a workbench and then mount them, but that is added time and cumbersome.

dusty

RFGuy wrote
dusty wrote There is no guarantee but it is highly likely that the Table Tube will rise to the center position inside of the 510 table rail when lateral pressure is applied by the thumbscrew. However, if we are discussing Main and/or Extension Tables - this in NO WAY effects the positioning of the table tops. If the discussion includes floating tables - yes the table tops may change relative position with respect to the table tubes (by an amount of approximately 1/32"). I don't think this would be significant enough to make Ed in Tampa get rid of his 510.

As for pointed (non-square) thumb screws:

510 able Thumbscrews.jpg
Dusty,

Thanks. I think you are forgetting about the potential skew of the floating table. What happens if the floating table front is locked in place closer to the main table than the rear lock or vice-versa? I believe this could happen with either the 510 or the 520 table systems, but given the greater variation on the 510 rail it should be worse. Separate from this is what happens when you do lock down the floating table on a 510? On the other thread it was suggested that the thumbscrew might bias the 510 connector tube up/down as it seats, whereas this is not possible on the 520 because it biases it only up and locks it to the rail in a tight fitting channel. Not trying to belabor this discussion, but it seems to me that there is potential for greater variation in floating table position on the 510 and the 520 attempted to fix this. In my opinion they did and the 520 is a definite improvement. Keep in mind Shopsmith repeatedly has stressed how fast the Mark V system is, e.g. with changeovers, etc. Many of us, or at least I, was told that I could install the rip fence on the floating table and go off and make repeatable cuts with it...and do so quickly. Not even talking precision here, but safe, kickback free cuts. After Scott's video and the other thread, I now see why that was a fallacy on the 510 using the floating table. Sure, Shopsmith owners can attempt to assemble multiple tables upside down on a workbench and then mount them, but that is added time and cumbersome.

Yes, there is a greater potential for movement with a 510 then a 520 but just how much. I simply contend that it is slight; not great enough to create a safety issue or a serious alignment problem. Not so much these days but I have cut a lot of sheet goods using the the rip fence mounted on a floating table with no difficulty.

RFGuy

dusty wrote Yes, there is a greater potential for movement with a 510 then a 520 but just how much. I simply contend that it is slight; not great enough to create a safety issue or a serious alignment problem. Not so much these days but I have cut a lot of sheet goods using the the rip fence mounted on a floating table with no difficulty.

Dusty,

Thanks. Yeah, I agree that I don't know "how much" of a problem it is either. IF I still had a 510 setup I would try to compare/contrast them. For me, and for Ed, there was a quality difference between our 510 and 520 setups, but to quantify what that difference was may not be possible now or worth the trouble. I mean we are happy with our 520 systems now. Other forum members are happy with their 510 systems. IF you have interest and want to try to quantify it, that is up to you. As long as we are all making sawdust and happy with the results that is all that matters in the end. I think that these threads have illuminated at least some of the "why" on what I experienced with my 510 system, but I could be mistaken. Thanks for the discussion as always and appreciate you looking into it and the excellent diagrams. Appreciate it.

dusty

510 and 529 Rails with Table Tubes..a comparison:

510 and 520 Rails with Table Tubes ...jpg

You have to use your imagination for thumb screws on the 520 rails.

The sketch with two vertical center lines shows how much the Table Tube is pushed with the thumb screw (1/32"). Not IMO enough to create a lot of concern Even if the 520 is 0".

I certainly do not believe this movement to be the root cause of the issues that have plagued Ed in Tampa.

I do hope that Scott does another YT video that touches on this.

JPG

Where did 1/32" come from?

Later version has over 1/16" slop.(0.070)

Original version had slightly over 1/64"(0.020)

dusty

Where did 1/32" come from?

Later version has over 1/16" slop.(0.070)

Original version had slightly over 1/64"(0.020)

510 Table Rail with Table Tube Secure and Unsecure.jpg