1/4" Bevel Edge Chisels

[Herman Trivilino]

Kenny, you asked about the amount of pressure you apply against the grindstone with either a tool or the stone grader.  In either case you push as hard as you want.  The harder you push the greater the cutting action.  With the stone grader apply lots of force, don't be afraid you're pushing too hard.

Look at the YouTube videos featuring Jeff Farris.

As Jeff (Moderator) said the trick is to apply more force to the long point side.  You should be able to produce shiny bevels that will wow those kids.  They will think all chisels are that sharp.

[Ken S]

Kenny, do you realize that this is not [oops, read "now", thanks, Rob] the sixth longest (most responses) thread on the forum? (check the forum stats).  Good topic.

Ken

ps After your schedule relaxes, I hope you post some information about the program at your school.

[Rob]

you mean this IS he 6th longest I'm guessing?

[kennyk]

After some more experimenting this morning, I am now convinced that there is something wrong.
I've squared the chisel in the jig, checked the usb is level with the wheel, set the height without putting any pressure on either leg when tightening.

After taking a few passes, the sharpie is wearing away on the same side.  I then put massive finger pressure on the side of the bevel that was untouched, and  the sharpie  ink is still not wearing off where I'm putting pressure.


I tried jigging up the skew chisel jig to run freehand against the usb but I managed to skew in the opposite direction because, in my opinion this jig is fundamentally flawed in design as well. there's no way to reference the side of the chisel is square in the jig, so there's no way on this earth I could guarantee that the skew angle I think I'm getting is the one I am actually getting.   
It is impossible to get a chisel level when the thumbscrew on the top is so far over to one side that it introduces a turning moment on the chisel as soon as it is tightened.  it doesn't help that the v-jaws dont grip the  sides of the chisel properly either.

I'm out of ideas and patience.

[kennyk]

A further update.

The ONLY way I can get anything remotely approaching a square edge is by repeatedly skewing the chisel in the SE-76 away from the registration edge and adjusting this skew.

the latest result was when looking down on the chisel in the jig, back of the chisel up, handle towards me that the chisel was pointing slightly left. using a square there was about 1.5mm gap at the top of the square to the side of the chisel.

What does that tell you?

[Tormek moderator]

Are you still working with the 1/4" chisels? Did you see everyone's advice to start with wider tools first?

[RobinW]

If you undertook the same tests as I did a couple of days ago, did you get similar measurement accuracy? That is the first thing to be clarified.

If the usb is bang on parallel with the wheel surface after truing, ie no light when usb rests on the wheel, and when the usb is clamped at the appropriate height to suit the required sharpening angle and the wheel to usb distances match the accuracies as per my measurements, I would suggest the following.

Pick a reasonably wide chisel 3/4" -1", ensure that the back is flat and no twist along its length (as best as you can ascertain - and you would be surprised how many are not great). A small twist between the part of the blade where it is clamped in the SE-76 and the area to be sharpened will show as skewed grinding. I have several, and I live with it.

Flatten and polish the back of the chisel for the last inch or so. I do mine on waterstones and then finish polish them on the leather wheel of the Tormek. Once that area is polished you should not need to touch the back again.

We are unlikely to have the necessary equipment to prove that the front face of the SE-76 (which is also likely to be rough from casting) is exactly parallel to the axis through the two mounting holes. Likewise we are unlikely to confirm that the reference edge inside the SE-76 is exactly orthogonal to the axis of the mounting holes. However we can proceed despite these unknowns. (Or in the words of Donald Rumsfeld - "there are known unknowns")

The side of the chisel may have a slight concave/convex shape so don't push against the reference shoulder in the SE-76. Put the chisel in the middle with say 50mm sticking out from the jig.

When clamping the chisel, bring the SE-76 clamp down lightly onto the chisel. Use a small square from the front face of the SE-76 to the side of the chisel, but be aware this is only a starting guide not an absolute angle guarantee.

Looking at the chisel end on against the light, see if there is any light showing between the back of the chisel and the SE-76, and likewise between the clamp and the bevel side of the chisel. Adjust clamps evenly so not inducing any twist, ensuring that when clamped the chisel is still at the perceived 90 degrees.

Set the grinding angle eg 25 degrees, fixing the usb as previously detailed with a finger above the threaded rod when clamping. Felt tip mark the chisel area to be ground and do a few strokes and check what is happening.

Because the chisel cutting edge of the blunt chisel is probably not square, and the plane of the bevel also angled so introducing more compound angles, then any shiny area of fresh grinding will probably initially show up as out of kilter. As per your previous photos this may appear ovalled rather than trapezoidal or as desired rectangular.

I would also keep going until I have a full width shiny area and up to the edge of the chisel. The reason for this is that I am then dealing with my grinding, not what was there, or half and half.

Assuming that the usb and wheel surface are bang on, then any skewing is almost certainly down to twist in the chisel; twist by offset pressures in clamping the SE-76, or most probably due to angular mis-alignment even by a very small amount ie the chisel is not at 90 degrees to the axis of the SE-76 mounting holes. This last effect is also most probable because we do not have means of checking absolute angles as explained earlier, and we set the chisel at a perceived 90 degrees.

Throughout all grinding I would frequently re-apply felt tip marker and check what is happening.

To try and correct skewed grinding I would first try applying more finger pressure to one side of the chisel and see if that induced minimal twist would yield the desired answer. You have to think carefully which side to apply pressure, and you are trying to reduce the long side of the chisel. It is easy to take the SE-76 with chisel off the usb, look at it upside down or back to front, and apply pressure to the wrong side.

If unsuccessful, (and because I would expect the angular error to be the problem) I would ease the SE-76 clamps, and adjust the chisel angle by a minimal amount - we are talking 1 degree effects being noticeable here -  re-clamp and try again.

This is a slow process initially but gets better with practice. Take care that the amount of chisel protruding from the jig hasn't changed much otherwise you have to reset the angle.

Also be aware of which angle, when added, or reduced, corrects the long side of the chisel.

It is not immediately obvious whether to add or subtract an angle to get the right answer. Try it several times as a separate learning curve and understand which way reduces the long side of the chisel and for why.

When it comes to checking the squareness across the end of the chisel, I sometimes check mine with a very small square, so that the error introduced by chisel side non-linearities is reduced. Also I tend to use the square only on the larger chisels, as eyeball square is more than adequate for the smaller ones and I do cabinet work.

I have not mentioned re-grading the wheel or using the leather wheel, as these are low down the priority list at this time.

By small angular movements of the chisel you should get a square end and parallel hollow ground bevel. It takes time, and without wanting to sound condescending, a load of patience.

By doing it from the middle of the SE-76, you are not reliant on the inside reference edge. You are also not relying on the front face of the SE-76 to give you 90 degrees. You are doing it by monitoring the effects at the area being ground.

You might think this methodology defeats the purpose of having a jig of this nature, and contrary to the sales videos. I have previously made my own comments in a similar manner, and I would not dispute it at the moment. What I am trying to do is give you a methodology to get success. Once you have this under your belt and getting confident that you can sharpen a blade proficiently, you then go back to using the reference edge and see how you get on. I didn't use my reference edge for quite some time, but lately have gone back to using it and it does work.

I do not want to be rude, but I could comment that I would not expect school kids to appreciate the squareness of a chisel, or the standard of work they probably achieve warrants it etc. etc. but that is inappropriate at the moment as like other contributors I am trying to help you up the learning curve. But is worth re-assessing what is an adequate standard to be achieved in the short term.

I am on the east coast, but I am not in a position to come and help as very tied up for the next month or so with wedding, family gatherings, club bbq organisation etc, so I will post when I can.

[Herman Trivilino]

After taking a few passes, the sharpie is wearing away on the same side.  I then put massive finger pressure on the side of the bevel that was untouched, and  the sharpie  ink is still not wearing off where I'm putting pressure.

Is that the side that's the long point?

[Mike Fairleigh]

I'd like to see some pictures.  One with the blade of your square against the same long edge of the chisel that registers against the inside of the jig (with a light behind it), and another with the stock of the square against that same edge and the blade of the square against the end of the chisel.

It's unlikely, but not impossible, that we've got a defective jig here.

[Tim H]

I just came from the shop after sharpening 2 new irons for a Stanley block plane and a Stanley 90.  The 90 was done first and I referenced on the long section at the rear of the plane when I placed in the jig.  I failed to use a square to see if the new blade as 90º  out of the box but I assumed it was.  When I mounted the new iron for the block plane I did check to see if it was square out of the box and it was. Also, the sides are straight.

With both irons the finished results skewed the edge so that it was not 90º to the side.  Both skewed in the same manner - so as the jig sits on the support the cutting edge sloops down to the right.

I could see this happening but thinking I can live with it and compensate when the iron in placed in the plane.  But the fact that they both skewed in the same direction makes me question my set-up and the reason I have read this post.  I will check the "squareness" of the support to the wheel and I will check the wheel and true as needed.  Other than this and the pressure on the iron while grinding (and other comments here and elsewhere) any other factor to investigate?
Tim

[Ken S]

From time to time I watch Jeff's videos.  This morning I happened to watch his chisel sharpening video linked here:

http://www.youtube.com/watch?v=kMCwG8xehGE

I think it makes sense to make sure we can get a basic very sharp edge.  Once we can consistently create a very sharp edge, then we can be concerned with the degree of squareness.   I do believe this is a two part process.  First the sharpness and then the finesse. I believe we are focusing on the finesse before we have solidly established the sharpness.  I believe we can benefit from watching (rewatching) Jeff, an accomplished Tormek expert, go through the process.

Ken

[Tim H]

I want to follow-up on my comments from last night.  I have some measurements.

First, lowering the slide bar down to the stone I get a perfect fit;  if anything, the stone might be a smig concave in the middle. All blades had sides that are parallel with the opposite side.  The Record and block plane blades we brand new.

Over the last two days I sharpened  4 different blade types (but a total of 5 blades); all were set for 25º.  Here is some facts about the 4 different blade types:

                                                        width           thickness

Veritas (for bevel up use; 2)               2 3/16th          0.182

Record (for #4)                                 2                     0.0885

Stanley block plane                            1 3/8th            0.0785

Stanley 90                                            1                 0.121

None of these blades came out totally square but I would judge the Veritas blades to be nearly perfect. But as you can see, as the blade width and thickness decreases I observe a greater out of square result.  I am not sure what the take away is. I am not able to give a measurement of how much out of square it blade is but results were very noticeable when held up to a light and that the 90 may have been as much as double the error of the block plane iron.

The Stanley 90, while a bit thicker than the next 2 thicknesses, had the worst results. It has the smallest width.

All blades were systematically moved across the stone.

The blade jig was checked and its fence to the front edge is square.

I guess my conclusion is that the thinner the blade, the less width it had there will be a tendency to have an edge that is not square.  But I admit I may be drawing the wrong conclusion.  Anyone care to comment?
Tim

[Rob]

I'm just back from a trip to Jersey o find the current update. Given what you have to get through Kenny, whats next? If it were me in your shoes I would either fix the Viceroy and do them on that or do them by hand on the Tormek using a known protrusion (marked on the chisel with a marker pen) to rough the 25 degrees and then grind a micro bevel only.

In other words, the time has come to change plan.  I know you want your students to get a perfect looking bevel but unless we get another approach sorted they're not even going to have sharp tools which is actually dangerous.  So for me priority 1 is get a useable edge in a classroom setting.  It is entirely reasonable to hand/by eye grind a micro bevel of 1mm at roughly 25 deg (tolerance of say 20-30 degree would still work in a practical setting).

Meanwhile I would be in contact with the dealer of the Tormek to discuss the problem (and probably try out a replacement SE-76) or ensure the Viceroy is working so you can use that while you decide what the future holds.

[SharpenADullWitt]

From time to time I watch Jeff's videos.  This morning I happened to watch his chisel sharpening video linked here:

http://www.youtube.com/watch?v=kMCwG8xehGE

I think it makes sense to make sure we can get a basic very sharp edge.  Once we can consistently create a very sharp edge, then we can be concerned with the degree of squareness.   I do believe this is a two part process.  First the sharpness and then the finesse. I believe we are focusing on the finesse before we have solidly established the sharpness.  I believe we can benefit from watching (rewatching) Jeff, an accomplished Tormek expert, go through the process.

Ken

I certainly don't see it that way.  I don't find it difficult to get things sharp on the Tormek, and coming from other systems, such as he did, I expect sharp isn't the problem.
It does sound like a bad jig to me. (that happens in any manufacturing process)

[Ken S]

I have always believed that Tormek AB is a reputable company concerned with customer satisfaction.  As such, I cannot imagine that Tormek AB would want to let this situation go unanswered.  I realize that Sweden is on holiday until August 4. 

Kenny's problems with the school's new Tormek are certainly well documented.  They are not only well documented; they are documented on Tormek's own worldwide forum.  I don't know how much of the problem may be due to problems with the individual Tormek unit and how much of the problem may be due to  operator error or inexperience. I would like to know, as I believe would many of the forum members.

I would like to see the UK Tormek troubleshooter, instructor set up a time to visit with Kenny at the school and isolate the problem.  The troubleshooter should have a replacement unit with him in case the problem is the school's unit. This should be done soon.

Whether the problem is in the Tormek unit or with operator error/inexperience, the troubleshooter should be prepared to coach Kenny until he is proficient with the Tormek unit. This should not be a hurry up quick overview; it should be a solid training session lasting until Kenny is confident with the Tormek.

The troubleshooter should also be authorized to refund the school's money and retrieve the Tormek.  I would hope this option would not be needed, as I feel the school could be well served with a properly used Tormek.

This customer needs to become a satisfied customer.  This has become one of the longest and most intense posts on the forum.  I want it to have a well explained and happy ending.

Stig, I hope you will become involved in this.  This incident will either confirm Tormek's commitment to customer service or leave many doubts about the Tormek product. I look forward to my ongoing faith in Tormek AB being reaffirmed.

Ken