Let us not jump to this or that and end up thrashing the wind.
Let us start at the beginning define the problem and logically and methodically work our way to a solution.
We can set Al checking a million things and miss the one thing that will fix the problem. Right now all we know is something is throwing the fence/fence rail relationship with the table grooves out. Is it a problem or an appearance issue. If it is a problem what is changing the relationship.
I can guess about 100 different things but it would be better to start at the beginning and eliminate each one, one at a time and solve this issue.
Ed in Tampa wrote:In my career as a trouble shooter for IBM I have seen bugs like this go missed for days because an ASSUMPTION was made. Don't assume anything prove each step in a logical Methodical manner and you have to solve the problem. The problem again has to be something is changing the relationship of the fence and fence rail as they relate to the table.
First let us prove we still have a problem. Since nothings says a properly working fence has to be parallel to ext table grooves let us make sure the fence is or is not in perfect alignment with the blade when on an extension table. Do this is order and don't assume anything do it and see.
First using only the front lock down handle on the fence insure you fence is perfectly (as close as you can make it) parallel to the main table miter slot.
Second using connecting tubes mount one of the floating aux table and only tighten down the front fence rail to the connector tube. Still use the rear connector tube but don't lock down the rear fence rail to it. So nothing is pulled out of alignment.
Third using only the front lock handle lock down fence on the front aux table fence rail and check if the fence is parallel or not with the main table miter slot. If it is then tighten the rear fence rail to the connector tube locks. Is it still parallel? If not then the problem is something is canting the table when you tighten down the rear. My guess the bench and way tubes are off.
If the fence remains parallel then use the rear Fence lock if it moves the fence then problem could be table and tubes are not properly the right size force the fence to deflect or something.
If in the third step the fence isn't parallel and if it is still out of parallel about the same amount on all three ext tables it suggests the problem in with the main table.
And we have missed something there.
Double check the main table fence rail is perfectly perpendicular with the miter slot. Check both miter slots. Once that is done. Get out the SS maintaince manual on main table adjustment and go through each adjustment to insure the table is correct. DON'T Assume on any step either do it or check it to make certain.
Once that is done and using only finger pressure or the front lock make sure the fence is parallel to the miter slot. Using only finger pressure or the front lock eliminates all possiblities with table width or fence problems.
Now mount a aux table and check again. If the fence is off then the problem almost has to be connector tubes are bent or the ext/aux table fence rails have been deformed.
I contend that the front lock squares the rip fence with the table (according to how it was aligned) and that the rip fence should not move AT ALL when the rear lock is secured. As a matter of habit, I assist in making certain that the fence has squared itself before I secure it. I do that by pressing the rip fence against the front rail as part of the positioning and locking process.
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
dusty wrote:I contend that the front lock squares the rip fence with the table (according to how it was aligned) and that the rip fence should not move AT ALL when the rear lock is secured. As a matter of habit, I assist in making certain that the fence has squared itself before I secure it. I do that by pressing the rip fence against the front rail as part of the positioning and locking process.
I agree and that is why I have Al do most of the checks using only the front lock. To eliminate all variables that may or may not be causing the problem.
We have to find exactly where the problem begins. Right now all we know is something is wrong somewhere.
Ed in Tampa wrote:I agree and that is why I have Al do most of the checks using only the front lock. To eliminate all variables that may or may not be causing the problem.
We have to find exactly where the problem begins. Right now all we know is something is wrong somewhere.
We don't yet recognize what the cause of the problem is but we do know an awful lot more than just that Al has a problem.
If there was such a thing as a "golden rip fence", many of the variables could be eliminated as possible contributors. As this all started, we dismissed the main table and all of its many parts as possible contributors because the rip fence was dead on.
But, it might have been dead on only because it was adjusted to be dead on while setting on a canted front rail.
It was not until that dead on rip fence was mounted on another table that the issue became apparent.
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
Ok. Everybody take a deep breath. Somewhere along the line I think the solution has been implemented and the problem appears to be corrected. I just wish I knew what the the heck I did to make it go away. I have had all the rails off the tables at various points, realigned the fence after taking off and putting back on the main table rails several times, shimmed the front fence and measured virtually everything I can think to measure. Still, I believed I still had a 1/16th inch offset when the fence moved to the floating or extension tables. I even measured it with a metal rule against the fence and up to the blade.
After I got Ed's post, urging me to go back and check everything again, I did. My blade is aligned to the main table slots within a few thousandths. The fence on the main table is aligned to within 2 thousandths (locking either just the front lock or both the front and the rear locks). Fence is also visibly aligned to the main table grooves although this is NOT a criteria for anything.
Per Ed's instructions, I mounted a floating table with connector tubes but only tightened the nuts on the front rails per Ed's instructions I mounted the fence and locked just the front lock per Ed's instructions. Took some measurements at the front and rear of the fence to the blade and the measurements were ... the same! The only thing I did differently this time was that instead of using my rule, I got my starrett square out. While it is too short to measure from the fence to the blade when the fence is on the floating/extension tables, I used the aluminum block that you use to align the 520 rails to offset the base of the square from the fence (yes, I mic'd both ends of the aluminum block to make sure it was a consistent width).
I then locked the rear fence lock and re-measured and got the same results. Tightened the rear extension tube nuts and retook the measurements and they were ... the same! What? Fence is still visibly skewed to the extension table grooves but again, that has never mattered -- except cosmetically.
Checked the second floating table. Same results.
Mounted the extension table (I know the rear fence needs shims) and got the same results even without shimming.
I will admit I am perplexed. This should NOT be the result because I have checked each floating table and extension table and my tests show the rails are parallel and the grooves are very close to perpendicular to the rails. But the measurements from the fence to the blade don't lie.
I am going to go back and recheck everything again this evening. Maybe I am just too exhausted and seeing what I want to see.
For now and until further notice, I am calling the problem solved. I also want to extend my sincere thanks to all who contributed to this thread.
Moving the non-.314 spacers may have changed things.
One thing to always monitor is the effect of the rear fence clamp. It should always clamp, and never skew!
At this point I would leave the boss 'projections' alone. I believe the machining of the entire boss has been replaced with a spot face or limited area machining as a cost reduction.
A mystery is why are there different sized spacers. I think I would be obtaining a bunch of them(local hardware store if cheaper than $0.80).
We are still assuming the interior tube mating surfaces of the rails are a-ok!
I do not have a GOOD way to check that 'independently'.
The 'mystery' of align now but not later(the aux table grooves) remains.
Perhaps it was always a 'DISTRACTION' after all!;)
I think this shall come up again!:rolleyes:
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
[quote="JPG40504"]Moving the non-.314 spacers may have changed things.
One thing to always monitor is the effect of the rear fence clamp. It should always clamp, and never skew!
At this point I would leave the boss 'projections' alone. I believe the machining of the entire boss has been replaced with a spot face or limited area machining as a cost reduction.
A mystery is why are there different sized spacers. I think I would be obtaining a bunch of them(local hardware store if cheaper than $0.80).
We are still assuming the interior tube mating surfaces of the rails are a-ok!
I do not have a GOOD way to check that 'independently'.
The 'mystery' of align now but not later(the aux table grooves) remains.
Perhaps it was always a 'DISTRACTION' after all!]
If you have extension tubes that are not perfectly straight, you may feel some resistance as you insert or remove the tubes from the rails. On that I would definitely agree.
However, just how bent does an extension tube need to be to adversely effect the alignment of main and extension tables? I think pretty badly.
I had some badly distorted 5' foots. Nick and I went around and around over whose fault that was. He contended that I bent them. I finally bought two new 5' tubes. They were not straight even before I installed them but that is another story. I cut the original 5' tubes into shorter pieces that I use 'til this day. I don't have any alignment problems that can be related to the tubes.
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
This is a kind of lengthy post-script to the problem I was having getting my rip fence to align when moving it from my main table to my extension/floating tables on my 520. It is a long, sad tale, but one with a happy ending (I think). Since it may be of some interest or help to others in the future, here it is:
Despite the best efforts of the members of the forum who offered their advice and solutions, I was never able to fully correct the problems I was experiencing with the rip fence. As a refresher, I was getting perfect alignment of the rip fence on the main table but when I moved it to the floating or extension tables on my 520 the fence was skewed pretty significantly. Even after declaring my problem solved, I found out it wasn't (bad measurements combined with wishful thinking and exhaustion).
For several weeks after I had prematurely declared my problem solved, I worked off line with another forum member (thanks, you know who you are) trying to figure out what was wrong and trying to correct the problem. The closest I was able to get was with shimming the main table rails.
Eventually too frustrated to continue, I contacted Shopsmith customer service and, after discussing all the usual alignment procedures (which I had already tried), I was told I could ship the tables and rails back to Shopsmith at my own expense for evaluation. This lead to an even longer saga that put me out of commission (not due to Shopsmith).
My first mistake was to allow my local UPS Store to package things for me. They did an inadequate job of it and the rails arrived at Shopsmith damaged beyond use per Jim McCann. There was also cosmetic damage to the tables. Jim McCann at Shopsmith was great about documenting the package/packaging and all the damage and giving me quotes to replace my rails and fix my tables.
Even though I had insured the shipment, I got a huge amount of run around from both the UPS Store and UPS itself. My advice: avoid this company like the plague. Amazingly, as a consumer, you can't even make a claim to UPS when you ship through the UPS Store even when you've paid for insurance. You are at the mercy of the UPS Store filing a claim on your behalf. UPS won't even tell you the status of any claim that may or may not have been made on your behalf by the UPS Store. As far as UPS is concerned, you are not the customer, the UPS Store is. Believe, I won't ever be a customer of either the UPS Store or UPS again.
My local UPS Store kept telling me the claim was being processed..... Eventually, with the help of Jim McCann (who knew a UPS representative in Dayton), I was able to learn that the claim had already been denied while my local UPS store was still telling me it was still being processed. When I told UPS corporate (not Jim's contact) that my local store was lying to me that the claim was still being processed, they didn't care one iota. Nice integrity there, UPS!
When I confronted my local UPS Store, they told me they were re-filing the claim and needed additional documentation, which I gave them promptly. More time went by. Claim still being processed. Finally, they admitted it was again denied and that was that, there was nothing more they could do. After some more run around from my local UPS Store "manager" I finally tracked down the owner (no small feat in itself) and I was able to get satisfaction, but only after I threatened him with a lawsuit and made it clear that I was in a unique position to follow through on that threat notwithstanding the relatively small amount of money involved. I really dislike having to make threats like that but sometimes there's no alternative.
Now, back to the issue with my tables, rails and fence alignment. Back at Shopsmith, Jim McCann put some new rails on my tables and mounted them up to a test bed at Shopsmith. He confirmed he was was seeing the exact same problems I was reporting: he could align the fence to the main table, but the fence went out of alignment when moved to the extension or floating tables. Hooray, I was not crazy after all!
How bad was it? Bad enough that Jim said things were unusable. He later confirmed that comment referred to the fact that the fence was skewing to the point where it would become a kickback hazard when used to the left of the blade (towing in). Luckily, I had always used the fence to the right of the blade (towed out).
Now for the source of the problem. I had assumed the problem was the main table since I was seeing the same skewing whichever floating or extension table I moved the fence to. Jim reported that the main table was fine, almost perfectly within spec and that the little ridges on the bottoms of the main table fence mounting pads were not interfering with the rails (one of my guesses that proved wrong). Jim also shot down another issue I had discovered: the table mounting pads on my main table were not exactly perpendicular to the table surface. According to Jim, however, still within spec.
Instead, the problem was with the floating and extension tables all along. Although the distance between each pair (front and rear) of fence mounting pads on the extension and floating tables were within spec, the distance between the left front and rear pads was nearing the lower limit of the spec and the distance between the right front and rear pads was nearing the upper limit of the spec on the floating and extension table. Because of the stack up of tolerances, the rails mounted skewed to the table and the fence would skew when mounted to the rails.
Because the tables were technically within spec, Jim told me he could not replace the tables. But because they were unusable as is, Jim offered to shim them and make them as accurate as any other. I must say, the fact that a table could be both within spec and a danger to its user came as a shock to me and I politely suggested to Jim that Shopsmith ought to reconsider its spec, but I also accepted his offer to shim the tables. After all, I wasn't even the original buyer of the machine and so I was surprised Shopsmith would even go that far. But Jim assured me that if something is not right when it leaves Shopsmith, they will take care of it even if you are not the original owner. Read that last sentence again slowly and let it sink in. That's a real credit to Shopsmith.
Even with all the equipment he's got to measure these kinds of things, it took Jim quite some time to exactly shim the rails on the extension and floating tables to the point where he could get everything to align properly when mounted. Jim then had one of the other employees package and ship all the tables, with the new and newly shimmed rails attached, back to me. Unfortunately, 2 rails arrived damaged! Unlike UPS, however, Jim was great about shipping out replacements immediately. I installed them, being careful to keep the same shims in the same place.
I have not had much time to play with my new set up because of work related issues. But I am happy to report that I did some testing and experiments last night and the fence now appears to maintain alignment when moved between the main table and the extension/floating tables.
I am also happy to report that the fence now visually aligns parallel to the grooves not only on the main table but also the extension/floating tables. Although those grooves are not intended to serve as a reference for fence alignment, if your fence is aligned on the main table but obviously not parallel to the groove on your extension/floating tables, that may be a clue that you've got a problem that may require some shimming of the rails.
One other point. When using the floating tables, Jim McCann reminded me that alignment will be impacted by the straightness of the extension tubes you are using and the orientation of the extension tubes within the rails. In fact, Jim told me he was going bonkers measuring my tables, shimming the rails to his measurements and then mounting them only to find out that the alignment wasn't perfect even though his measurements said it should be. Then he remembered the 5 foot extension tubes he was using weren't perfectly straight and he began playing with the extension tubes. Jim's advice to me was to experiment with my extension tubes (even my short extension tubes aren't perfectly straight), rotating them by small amounts and tightening, checking for alignment, loosening, rotating, checking again until I got the best possible alignment with my tubes and then to mark the tubes with a permanent marker (not really permanent on the tubes; it can be removed with alcohol).
So that's the rest of the story so far as alignment of my rip fence goes.
Thanks to all who previously provided assistance. Thanks to Shopsmith customer service and thanks especially to Jim McCann.
Al
Gale's Law: The bigger the woodworking project, the less the mistakes show in any photo taken far enough away to show the entire project!
dusty wrote:...
I rely on the bosses because they are milled surfaces. ...
Note: I speak here only with regard to the newer tables. ...
Wholly Moly, what a can o worms.
My older (mid '80s ver.) tables those milled surfaces were all different, and like Union Bosses cared only for themselves. The bosses themselves were not co-planar, were different thicknesses (even on the same table), and different "textures" (for wont of a better word), as if they had been milled by a hand grinder, using varied grit no less. Heck, I coulda made better tables out of cream cheese.
Hopingly noone else got stuck with those vintage pieces of garbage, but still, beware of the semi-oldies!
Mark V 520, Power-Pro!; Speed Reducer; B/S; Jointer; ShopMate DCS; SS Tenon Master; Rip-Strate; Incra; BCTW; DW734; var. SS sanding systems; Wood River;
algale wrote:...
Now for the source of the problem. ...
Instead, the problem was with the floating and extension tables all along. Although the distance between each pair (front and rear) of fence mounting pads on the extension and floating tables were within spec, the distance between the left front and rear pads was nearing the lower limit of the spec and the distance between the right front and rear pads was nearing the upper limit of the spec on the floating and extension table. Because of the stack up of tolerances, the rails mounted skewed to the table and the fence would skew when mounted to the rails. ...
Al
Etc., etc.
Well I'll be darned! That is EXactly what I found with my old tables. The pads were all over da plaze. (among other things) Wound up buying a complete new set, after probably a hunnert hours of torture wit dem thangs.
And until this moment I never really believed what I had seen.
THANKS Al.
Mark V 520, Power-Pro!; Speed Reducer; B/S; Jointer; ShopMate DCS; SS Tenon Master; Rip-Strate; Incra; BCTW; DW734; var. SS sanding systems; Wood River;
