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No, but the shiny edge.... 

I've got a granite lapping block  http://www.axminster.co.uk/small-granite-surface-plate which is probably as straight as I'm going to get.  when I put the usb up against it, with the legs upright, I'm getting a tapered gap that starts a couple of inches after the micro-adjust leg.  it's a bit tricky to measure but I managed to slip a 4 thou feeler gauge  (think that's about 0.1016mm) under the gap at around 3/4 of the way along.  it's not exact but there is definitely some light.   also it sometimes feels like there's a slight 'rock'  to it. but I was rushing a bit when I did it.
Due to the weld I can't tell if it's got bend in the other axis, as the support doesn't lie down flat on the granite.  Unfortunately I don't have an accurate enough straight edge.  I could use a 12" rule but I suspect its nowhere near accurate enough.

I'm planning to bring the T-7 home tomorrow night and spend most of next week when I am on leave to look at it.     

Did you mean the motor bushings? or something else that I should check?


Sitting down with a nice hot cup of Rooibos tea, (I've had my coffee quota for the day, 2pints of black!) I'm tryin to reason out what could be causing the problem.   The obvious one is user error.
The only other possibilities must now rest with the interfacing between the surface of the grindwheel and the edge to be sharpened.

So that means the areas I need to look at are:

a) bent support bar
b) support bar legs not 90 degrees
c) support bar not in correct alignment with the wheel. (squint)

the thing that I've noticed when I tighten the support legs is the tendency for the non-adjust leg to be pushed away from the screw (as one would expect).  What if the other leg isn't being pushed as far and it's introducing a squint that way?  as the microadjust is the pivot point, any point further away on the other side of the pivot would automatically show the opposite error but larger.  I could be barking up the wrong tree, but I'm now starting to clutch at straws trying to resolve this.

Yes, it is tight.  I'm wondering if it's got a slight downwards bend in it.

no it's fine when it's clamped down.  however it's no good to check if the bar is parallel given that I can move it  3mm before I clamp it!

I've just received a replacement SE-76 from Brimarc, the UK distributor.  I'm still getting the skew with every  single chisel.

The only way I can correct it is to physically pull the support bar up with my left hand as I work on the chisel in either SE-76 with the other hand.

regarding the 110.   there's around 3mm of wiggle room inside the mounting hole. That's far too much play on mine to give any meaningful results, and far more than the play on the support legs.

I've had a look at the edge of the wheel against the 110. and it's convex, with a high point towards the middle.   I've tried truing it with a number of passes.  I've set the height as per the instructions and run the TT-50 back and forward a few times without adjusting the height.   There is definitely something wrong here because the diamond tip is still  catching the low point at the outer edge after several passes back and forth.  I'm starting to get really fed up with the machine again. At this rate I'm going to need a new wheel very soon.  It's down at 235 already because I can't get it level.

Is the TT-50 meant to rattle?  is there meant to be 0.5mm vertical play in the threaded square bar section that holds the diamond tip?

For the level of performance this machine promised,  the tolerances that I've enountered are shockingly bad, that it is very difficult to get an acceptable result.

I'll be honest. If I'd personally shelled out for this machine, It'd have gone back a long time ago.  I've not got one single chisel to an acceptably straight AND square enough edge that I'd use in my own guitar making workshop.   Even the plane blades are more convex than I'd like.  I'm used to getting far more accurate results with nothing more than Japanese waterstones, or 'Scary Sharp' (3M lapping films on float glass)

The further I get into this to troubleshoot, the more problems I'm experiencing.  With this level of vertical play in the TT-50  I cannot see how it is possible to correct the curve on the stone, as the tip has a tendendency to drop.

[Robin made some good points about the lack of a Tormek presence at the major annual wood show in Scotland.]

Robin made some good points about the lack of a Tormek presence at the major annual wood show in Scotland. I attended a more local show in Hartville, Ohio. I was hoping to talk with the Tormek rep.  The Tormek rep was a no show. I ended up purchasing a sharpening product from a competitor. 

It's a moot point, as the Scotland Show has been cancelled this year. 

I'll give the 110 method a try tomorrow.   

I've still got problems with truing the wheel.  when I was trying to true it, the outer edge (EZY lock side) always falls away, about 1/4 - 3/8" in.     

I've noticed that the first inch of my USB is slightly tapered. is this normal?

The uncorrectable skewing (with a correctly set chisel in the 76) has re-emerged after another truing with the TT-50.  During sharpening, the chisel slipped out of the 76 and gouged the wheel, necessitating a re-truing.  I only managed one chisel before it was time to finish up today, but in order to get a straight edge, I had to skew the chisel considerably. 

So I'm still convinced I have a problem somewhere. I'll need to check what's going on tomorrow. 

regarding the setting using the TT-100, it's not really of much use for most of the chisels I have because they're all far too short to use even the 55mm stop.

When tightening the USB, I've always applied pressure to the non-micro adjust leg (or really in between the two legs to put pressure on both), because it just seems to make sense to offset the cantilevered weight of the long horizontal rod before tightening.  IMO there has to be some play in the sleeves, otherwise it would be too fiddly to adjust easily.

I agree,  however it is my feeling that there is too much play in the sleeves.  Tightening the non-adjust leg also moves it front to back by around half a mm, which can also skew the usb above the wheel.  If I get the chance I'll experiment with some masking on the support legs.   However it's not going to be for a couple of weeks I suspect.


In other developments, I've been moving forward with some 1/2" and 3/8" (and 10mm) chisels.  I'm still getting a bit of skewing but I can correct this with huge pressure on the long point.  it's the point closest to the inside of the wheel.   I'm starting to suspect that the previous grinding is having some bearing on this.  If I ever find a blade that's squareish, I'll know more!   

However I'm able to do some troubleshooting now, so this whole saga has taught me that at least.  if I can't correct the skew I have a few things to try, and it's a case of getting a feel for the likely culprit. 
I've done nearly one whole classroom's worth of chisels.  Once I get the last of the 1/2"ers done I can start to tackle the 1/4". but most of these are firmers rather than bevel edged so that should help in terms of aligment problems.

Kenny Nice stand .What height is it and it is .

Just measured, from the ground to the top of the rotating section is 33".     I think the sides are 29" high but by the time I'd put the top and bottom on, then  the extra top and rotating section, and the feet, it came out at  33".

I took the dimensions from the leaflet that came with the T-7 describing the stand, but I think the height is around 30".  I'll need to check, as I added the extra 1 1/2" inches of height with the extra plinth and rotating platform.  then I put feet on it, so it's probably close to the 32" in the leaflet,  but  I'll check with a tape measure tomorrow.

Thanks, Ken.  The difficult bit was manhandling the 8 by 4 sheet of ply on the Table Saw!

I'm going to try to explain this one a bit more clearly...

The issue is that the usb legs rattle inside the sleeves  to the extent that the weight of the chisel in the SE-76 is pulling the support down over the wheel, leaving the gap on one side of the chisel,  until it is corrected by pressure on the other leg, as shown in the second photo.   For the avoidance of confusion, this is PRIOR to tightening the locking screws.   Therefore if I mount the chisel correctly, slide the SE 76 onto the USB, adjust the angle and tighten the screws without further checking what I get is the first photo.  if I put pressure on the non-adjust leg before tightening, then I can now achieve a square grind.

(The chisel was previously sharpened on a Viceroy Sharpedge with a badly dished stone, causing a convex curve in the blade.  In fact every single one of the couple of hundred chisels sharpened by the previous technician on the equipment show the same curve.  I am trying to finally give the teaching staff a proper level of sharp equipment for the pupils to work with. )

I am still concerned about the amount of play between the sleeves and the support legs, as shown in the the gap in the first photo. 

Also, I've never managed to get a completely flat surface across the entire width of the stone.  In fact using the grading stone seems to exacerbate the curve.  In my conversation with Rob on the phone last week, he seemed (unless I have picked him up wrong)  to indicate that a bit of fall away at the corners was not an issue.   My experience over the last few days is that a good amount of finger pressure applied in the correct place, coupled with judicious and frequent checking with a square can more than compensate for this.   However it cannot compensate for a misalignment of the chisel edge to the stone due to the misalignment of the USB prior to tightening the locking screws.

Edited to add another thought:

The weight of the USB on it's own does not show the issues as much, so the usb will sit parallel to the stone surface.
Further the TT-50 is much lighter so does not cause the cantilever effect that the SE-76 loaded with a chisel does.