1/4" Bevel Edge Chisels

[grepper]

What an amazing long lived tale.  Gotta hand it to you Mr. kennyk for sticking with it so long.

I think you are right on with what you need to check.  (Clutching at the correct straws, and barking up the right tree). 

The strange thing to me is that this is a very simple mechanical device, with only a couple of things that could affect alignment.  A wheel, a shaft, the control bar and the bar's attachment to the case.

I'm starting over a though I had not been following this. I suspect this has already been covered, but if  if I found myself in your shoes I would do this: 

1. You mentioned your last post that, "So that means the areas I need to look at are: a) bent support bar".  Well..., Is it or is it not?  Whatever it takes, you need to get that out of the way.  I mean, especially at this point, you really need to be able to completely and finally resolve that question first.

Is the control bar and it's legs all square, 90 degrees and straight?  That should not be that hard to verify absolutely, once and for all.  A square, micrometer, dial indicator, lay it on a flat surface or whatever.  Be sure to measure the distance between the two legs at the top and bottom of each to verify the one that is welded is square to the other. 

2.  Verify independently that that each of the sleeves on the top of the case that the control bar goes into are 90 degrees to the top of the case.  That could be a real head scratcher if they are askew!  Use a square and lay it on the top of the case next to each one.  Then, stick the long end of the control bar into each sleeve, one at a time.  Lay a square on top of the case next to the bar sticking vertically from the case and use a micrometer or a block of wood or anything to measure the distance from the bar to the square at the top and the bottom of the bar.  Considering the amount of skew that you are talking about, it should be obvious if there is an issue there.

3.  So, if the bar is straight and the mounting sleeves are straight, bolt the control bar into the machine as though you were going to use it, and test again for straightness as in #2.  A). Like you mentioned, does it go out of alignment when you tighten the control bar mounting screws? Push/pull on the end of the control bar when it's bolted in.  Is there some sort of movement or play?  B).  Check the alignment with the bar close to the when and when it's pulled up.  Does it change?

The strange thing here is that as long as the top of the control bar is straight and vertical movement of the bar up and down is straight, it should not matter what angle the bar horizontal relationship to the wheel is.  For example, if you rested the bar on the wheel and it touched the outside of the wheel but was oh, say, 10mm off the inside edge so that that bar was really jacked at an angle, as long as vertical movement was straight, the angle between the wheel surface and the bar would remain constant when the bar was raised.  Once you ground the wheel to be parallel to the bar it really wouldn't matter.  The bar and wheel surface would still be parallel.  It would be strange to work with, look odd, and you would have a strange angle shaped wheel, but it should still work just fine.

4.  Grab onto the grinding wheel with one hand and the honing wheel with the other.  Push/pull up on one down on the other.  Any movement there?  If there were, I suppose that could change the geometric relationship of the wheel/bar when the machine torques under running conditions.  You might not notice there is any play when the machine is just sitting because of the pressure of the drive friction wheel against the motor shaft unless you yank it around.  I think this unlikely, but if it were true, the angle of the grinding wheel could conceivably change when the machine was running.  I'm barking up trees and grasping at straws here too!

[Ken S]

Good post, Grepper.  If, by chance, one or both of the vertical sleeves is not properly aligned, I would think it highly unlikely that the horizontal sleeves would also be misaligned.  If the support bar is properly aligned in the horizontal position, but hot the vertical position, I would suspect one or both of the vertical sleeves.  That doesn't seem very probable to me, but, I think it is another variable to quickly and easily rule in or out.  Sooner or later we will run out of variables. We will get to the bottom of this.

Ken

ps I couldn't think of the term "sleeves" yesterday.  You have been reading your handbook!  Carry on.

[grepper]

Thanks, Ken.  Kenny is talking about flat chisels, done with the control bar mounted vertically, right?  It could very well be that I missed something.  But either way, a lot of the principles are the same.   I have been more or less following it since the beginning and have not read every word.  Big post!  Is it the biggest?

I was struck by how long this has been going on, and how much work Kenny has put into trying to resolve it.  But you're right... I'm sure it will get resolved as long as he has the patience to stick with it.  Got to hand it to you Kenny!

[Ken S]

Grepper, go back to :in the shop" and scroll down to "more stats".  This is the second longest post on the forum. The longest had 130 posts.  that thread should have been several unrelated threads.  (I remember it.) This one is much more focused and relevant.

Kenny gets the perseverance award!

Yes, chisels are normally ground in the vertical position.  However, I don't see why the horizontal position would not work.  It is slower.  At this point, if it works, it is actually faster!

I believe there is much in this post of benefit.

Ken

[RobinW]

If kennyk does not have success in the next couple of days, he should return his machine to the supplier, or Brimarc as the importer, and get them to verify that the machine and its accessories meet specification (if defined).

Despite clawing his way up the learning curve, like we have all done, to me the most significant point at the moment is kennyk is still not achieving a flat surface across the width of the stone. Unless that is consistently achieved, the resulting sharpening and other issues are secondary.

If Brimarc do not have an expert available in Scotland to go and check out the machine on site, then Brimarc (on behalf of Tormek) should just exchange his machine. If they don't want to give him a new unit, give him a demonstration unit which has been checked out and proven so that if he gets skewed sharpening it would then point at operator error.

We are all guessing at the root cause, or causes, of kennyk's problems, and it is difficult without specific measurements and the elimination of the usual suspects one by one. Only then will a solution will not occur.

[Ken S]

I agree, Robin.  Admittedly we don't know the full story, nor does Kenny at this point.  We are not even sure if the problem is the machine or the operator.  It is time to verify that the machine is either defective or functioning properly.  It is also time, if the machine is ok for someone in the Tormek chain to make sure Kenny is well coached in using it.

Judging from a map of the UK with red flags by the stockists covering the island, someone in the Tormek sales chain should be able to step up and solve the problem.  Also, judging from the lack of other similar complaints from the UK right now, it doesn't sound like the existing service people are overwhelmed with other customer problems.  I agree that a known good unit might even be superior to a brand new unit, assuming it doesn't have too many miles on the odometer.  It would be sporting to give Kenny the choice of new of demonstrator, and send an experienced demonstrator with the new unit to coach him.

This very long post will either bode well or ill for Tormek.  Until it is successfully resolved, if I was a prospective buyer, I might be hesitant to invest in something which might or might not work.  Someone in the Tormek chain needs to fix the problem, whether it is in the unit or the training of the operator. The resolution should happen soon.  This has dragged on for too long.

Ken

[kennyk]

I think I'm getting closer to solving the issue.

I've used a couple of cable ties (zip ties ?)  on my TT-50 and have finally got a true wheel.   it was oval as well, which probably didnt help matters. 

After truing I'm still getting the same grinding pattern that I've been getting on the last 100 or so chisels.
To Rule out 100 identically wonky chisels I decided to attempt one that definitely had not been anywhere near the Viceroy so I dug out one of my Dad's old Stanley 5001 chisels, that I've used for guitarmaking. 
When I tried to sharpen it, I got the same skew appearing. so it's definitely not the legacy of the viceroy machine, or the chisels.

A square against the side of the wheel shows a tapered gap when the USB is resting against the wheel, which I think is the culprit.
To test my theory I started running everything in reverse.  So I took the USB and mounted it on the front of the machine like you would for the SVS-32.  Then I took the SE-76 and mounted the chisel upside down at the wrong end of the jig - completely away from the registration edge.  I ensured it was square, and got to work.

Bingo, straight edge.

So I tried it again with the second SE-76 that Stig had sent to me using a school chisel.  it's also straight, after a bit of mucking around- it wasn't entirely square in the jig first time.  So I tried another, my 5001 1/2".  That is also square.
I'm about to try another School 1/2".

However I now suspect that my vertical mounting sleeves are not parallel to the wheel, which would explain pretty much everything.  the curved blades as a result of fighting the skew.

Thoughts?

[kennyk]

just thought I'd add this, to show what I mean

[Ken S]

Kenny, I applaud your sticktoitiveness and your diagnostic ideas.  Now that Sweden is back from holiday, I think it is time for Sweden to send you a known good factory tested unit.  I don't mean a new unit in the box; I mean a new unit which Stig or another experienced associate has taken out of the box and used to accurately sharpen several tools. a thoroughly overinspected unit! It should be sent to you with return shipping paid for your unit (assuming the second unit works for you). I would think quality control would want to examine your unit. I hope when that happens that Stig will post the results.

Whether the problem is with your unit, operator error, or a combination, this situation should be happily resolved. It will be a good learning situation for your students.

I look at the forum stats from time to time.  Usually the guests viewing the forum outnumber the online members by at least fifteen to one. That's a lot of potential Tormek buyers following your difficulties, Kenny.  I hope those who continue looking will see a successful result, as well as many more future posts from you sharing your discoveries.  You have certainly moved beyond Tormek 101.

Ken

[Stickan]

I´m  in direct contact with Kenny also and have promised him that we will solve this.

Stig

[grepper]

Yesterday a person gave me a chisel to sharpen with a fine divot right in the center where he had hit a nail.  So I got the wheel nice an coarse and started grinding away.  Soon I noticed the chisel was getting out of square.  Exactly the same issue Kenny is having. 

Upon inspection it was easy to see what was happening.  One side of the bevel was not touching the wheel.  I didn't have time to mess around with it and try to find out exactly what the cause was, so I tried just pressing really had on the side of the chisel that wasn't contacting the wheel.  That didn't work.  I ended up getting it sharp and square by hanging the chisel half way off the wheel so I was only sharpening half the bevel at a time.  That worked, but it was a goofy thing to have to do.

Like I said, I didn't have time to muck around with it, but I thought it was interesting that it looks like I'll have to.

Kenny... You are not alone.

[SharpenADullWitt]

I mentioned checking the sleeves to see if they were tight.  I found a post here, that mentioned they should have some side to side play, due to minor differences in the USB (welding/heat can cause some issues).  I would see how hard it is to take them off completely, then reattach. (would also see if the metal housing under them is dimpled or something, causing it to not be parallel of if the sleeves themselves, off the machine, have an issue (angled instead of perpendicular drilled).
I second Ken's opinion of your attitude in finding the problem.

[Ken S]

I looked inside my Tormek with the grinding wheel removed.  The sleeves appear to be held onto the frame with nuts.  The largest metric wrenches own are 19mm, too small for the nuts. 

Do the sleeves fit into precisely sized holes or are the holes oversized to allow for some adjustment?  If Kenny's sleeves are out of alignment, that might be the problem.

Ken

[Herman Trivilino]

The sleeves appear to be held onto the frame with nuts.  The largest metric wrenches own are 19mm, too small for the nuts. 

I think I used a large crescent wrench when I took mine off recently:

http://forum.tormek.com/index.php?topic=1886.msg10023#msg10023

Do the sleeves fit into precisely sized holes or are the holes oversized to allow for some adjustment?  If Kenny's sleeves are out of alignment, that might be the problem.

I don't think there's any play or adjustment.  Those slots are punched into the frame and that determines their locations. 

You may be onto something here, Ken.  Just now thinking about it.  The axis of the grindstone must be precisely parallel to the USB's horizontal rod.  If the position of those slots is off just a bit then no amount of adjustment or grindstone truing could make up for it, and it would produce the very type of issue experienced by Kenny.

[grepper]

I posted a few posts back that I sharpened a chisel and it ended up out of square.  The resolution to my issue was simple.  I put a square against the side and over the top of the grindstone and it was obviously not flat.  Additionally the bar did not lay flat against the stone. 

Truing the stone fixed it.  I have not sharpened another chisel yet, but I doubt there will be any problems.

As far as to Ken's idea that maybe the control bar mounting sleeves are not aligned, that's super easy to confirm.  Just lower the bar so it lays against the wheel and put a square against the side of the wheel and along the bar.

The thing that gets me about Kenny's problem is that it does not seem to me that it should be all that difficult to figure out.  By that I mean:

1.   Bar is straight and legs are straight and square.
2.   Stone is flat.
3.   Bar is square with the wheel.
4.   Chisel lays flat against the wheel

That has to work... Right?  Unless you do something really wonky when sharpening, it's almost hard to go wrong.

The first three are easy to check with a simple square.  The fourth is obvious.

Addition:  I guess the jig could be funky and not holding the chisel square with the wheel, but that would be easy to check with a straight edge against the side of the wheel, or just by looking at it.  I think that's unlikely... but could happen I guess.