flattening LN blades

[Alf]

When I used to grind my blades I found there were two problems. The first was the potential for overheating and ruining the blade (I didn't have a wet grinder). The second was the problem Sean is having in consistently achieving a square edge, despite using a good guide.

Both of which are largely, or wholly solved with practice. Over-heating is also helped by correct choice of wheel (in my case a hand cranked grinder and a coarse wheel solved things in that respect). But practice at grinding is needed - just like everything else, no-one's born with the ability to use a grinder successfully. The difference is that some things we like to practice, like planing, whereas grinding blades is seldom in the top ten of fun things to do. :lol:

Cheers, Alf

 

[sean_in_limerick]

you are sooooo right Alf, i hate grinding - it can be a painful experience as well if you finger slips off the blade! Certainly i need more practice i'm just hoping that i pick something up from how other people do things.

 

[Frank D.]

I've actually come to like grinding, although after a few hours it does get a little tedious. I learned a trick from one of Mr. Charlesworth's articles on how to keep blade geometry when regrinding the primary bevel. He proposed not to grind right down to the edge, but to leave a hair's width of unground metal right at the cutting edge. Actually when he proposed this it was primarily not to wear down the blade prematurely, but I've found that if you start grinding with a square edge, it also has the benefit of preserving the geometry. With a little practice you can really leave just the slightest bit of the cutting edge untouched. It's the same principle as when you want to correct an edge that's out of square: you grind a flat on the cutting edge to make it square (with the blade at a 90° angle to the wheel), then you grind at the correct angle (say 25°) until the flat you previously created has just about disappeared. You shouldn't completely grind out the flat (i.e. grind all the way to the cutting edge) because it's your reference and if you did you'd risk recreating a new edge that's out of square. So leaving 1/64" or 1/100" unground along the edge makes keeping the edge square a lot easier. No jigs or engineer's squares are needed while grinding.
Mind you I don't use a Tormek, and once I set the tool rest at the appropriate angle, I do the grinding freehand. I don't know how easy this would be on the Tormek, but I assume it's possible because Mr Charleworth also uses a Tormek.

 

[engineer one]

frank that seems a very sensible way to do things
i must say that to me the major problem with the tormek
holding jig is that it has two screws, and you have to be careful
about tightening them down properly i have considered putting
a second piece of metal of the thickness when i am doing very
thin chisels for instance, so that you do not skew the blade to
some extent.

actually i would like to know from someone like DC, derek in oz,
or even Rob Lee, and TLN about how straight and square the sides of
plane blades are. are they ground to width, or just cut on a big
machine, and therefore subject to some irregularities.

once again we are getting really technical, but it will help
us all in the long run.

we have said it before, that first you have to learn that new tools are
not completely sharp, then learn how to get them to a stage
where you are happy with them, and get pleasure from usage.
then you start being unhappy, and look for more accuracy.
then you start to look for those methods like those of DC which
go beyond the call of duty.

most of us here are not full time cabinet makers, we all do many things
and what we are looking for is a compromise between good results,
and extreme sharpness.

i have to say that i accept i was lucky to afford the various tools i
have bought from the dutch ones, which were really inexpensive for
the quality and range, to LB and LN, plus my tormek. but looking
at the maths, i wonder whether it is more cost effective to buy LV or LN
and not have to cost in the time value that not flattening the sole
costs, to buying an older stanley or record, and having to spend
hours flattening the sole, and then changing the blade and maybe handles.

personal view as usual, but i would actually prefer to spend the time
woodworking which is why i have the tormek, then finish on
either the water stones/or diamonds, and then see about getting
a camber finally.

my one hundred cents worth again.
paul :wink:

ps if someone had not pointed it out, i would not have guessed who was being talked about, and i think many might well have been as ignorant
as me :twisted: :twisted:

 

[deirdre]

i also find that getting a consistent 25' primary bevel is no easy task on the Tormek - i know that the actual angle doesn't really matter but i have found that it's difficult to setup accurately even with the angle setting guide that Tormek supply.

Do you have a model with the micro adjuster? If not, that may help a lot.

http://www.sharptoolsusa.com/shop/?page ... fd4f6dceb8

 

[engineer one]

if it is a newer model tormek, you get this as standard.
paul :wink:

 

[David C]

It is odd how easily one makes exactly the sort of mistakes for which one criticizes others. Thank you Derek for your explanation.

In future I will do my best to stick to technique about which I know something!

Leaving a sliver of the previous honing is much recommended.

It is possible to grind an embryonic curve on Tormek if your guide is sloppy, and worn like wot mine is.
Just lift one side of blade while pressing down on the opposite corner. But do please watch fingers do not get trapped.

It should be possible to hone a curved edge on a narrow stone. Using point pressure, in the places where you wish to remove metal.
Speed of metal removal seems to be a function of pressure.

Tormek has some quirks which take a bit of getting used to.

I set bar at "my standard height, 9mm". Then dress stone with diamond device. I get a lighter easier cut, by inserting two layers of 240 grit W&D under the diamond cluster, when setting the restraining bar. Then I do not move the bar, as it is unlikely to be parallel to the stone surface again, if moved.
When an acceptable angle has been achieved, not the projection "for that tool." This allows repeatable grinding angles.

Narrower chisels can be difficult. Japanese are rarely parallel in crossection. The standard jig unfortunately jigs tools from the wrong side. i.e. not from the flat side.
Be prepared to fiddle with the clamping plate. It needs to be relatively parallel to the fixed plate.

Use black felt tip on the bevel to judge relationship between present grind and previous grind. Fiddle with clamping plate to home in on satisfactory grind.

Many honing guides of the wide roller & training wheel type also suffer from this problem!!!

Busy this week and next with short course, & unfortunately lost a lengthy post this morning just before sending.......

You won't be hearing from me for a while....I believe that many of the answers to common problems are already available in my books

David Charlesworth

 

[Scott]

You won't be hearing from me for a while....

That's very "Captain Oates"!! Don't disappear completely. People respect your opinions and want to hear what you have to say!

Regards

 

[MikeW]

You won't be hearing from me for a while....I believe that many of the answers to common problems are already available in my books

:lol:

David, I apologize for my part in your making this decision. I believe none of us is beyond scrutiny--me, you or Derek. I think we should all be able to question methods, techniques, inconsistencies and application of these in any given situation where a lack of understanding ensues. It is the attributing or assumption of moral or ethical defect which often stirs the passions.

For my part, I need to be careful in what I write at times as the pseudo-familiarity which comes from longtime exposure in a forum prompts me to treat someone as if I actually knew them and they were sitting across the table with a good bottle of red wine between us.

Part of the value of a forum is a broad range of experience. We would miss your input.

Take care, Mike

 

[MarcW]

...
You won't be hearing from me for a while....I believe that many of the answers to common problems are already available in my books
...
David Charlesworth

David,

I learnt much from your book, yet not much enough. I watched your dvds, yet I have questions. The one that mostly intrigues... but that for later. I found this place where woodworking exchange happened and I was more than glad about it.

Two weeks back I put some paving stones as border to help my girl-friend's brother ... well he burns electrons... It was a pleasant task and reluctant too, nobody interfered. I thought this would be a great profession, just like my grandfather, self-employed and free. I realized that my profession as teacher is quite not that gorgeous. But once settled and...

What I want to come to is... I need to do woodworking because of my profession, I - viewed as a machine - can't work without wwing. I'm in deep need to have some touchable results at the end of the day. So please tell me what the ... you're doing to flatten long stock, i.e. 3 to 7 feet long. :wink:

Marc

 

[Midnight]

So please tell me what the ... you're doing to flatten long stock, i.e. 3 to 7 feet long.

It's no secret that Mr C prefers to use woodmunchers to do the bulk of his stock prep...

 

[David C]

Marc,

I think you will need a long straightedge and some winding sticks.

Longer planes are hepful. but not essential. We built our workbenches with 5 1/2 s! because that was all we could afford in those days.....

In general longer stuff is flexible, and often restrained by a carcase, or corner joints, so, extreme accuracy tends to be less important.

David Charlesworth

 

[MarcW]

Marc,

I think you will need a long straightedge and some winding sticks.

Longer planes are hepful. but not essential. We built our workbenches with 5 1/2 s! because that was all we could afford in those days.....

In general longer stuff is flexible, and often restrained by a carcase, or corner joints, so, extreme accuracy tends to be less important.

David Charlesworth

Thanks David,

So nihil novi sub sole. That's quite a performance to plane long stuff with a jack.

I apologize for having squeezed you to answer, it was a little late ccasion5: that evening. I'm sorry.

So now I will go and get those dovetails done,

Marc