Author Topic: Skew chisel grinding.....was a grind!  (Read 22564 times)

Offline Ken S

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Re: Skew chisel grinding.....was a grind!
« Reply #30 on: June 14, 2013, 03:35:15 am »
Rob, would you please post some info on your father's skews?  I'm starting to think he used some worn out files.  (a common practice)  If he did, and didn't reheat them, you are certainly a devoted son to try to reshape them!

Ken

Offline Ken S

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Re: Skew chisel grinding.....was a grind!
« Reply #31 on: June 14, 2013, 03:37:42 am »
ps.....Nice looking wands.  Well turned.

Ken

Offline Rob

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Re: Skew chisel grinding.....was a grind!
« Reply #32 on: June 14, 2013, 10:26:18 am »
What an interesting idea...worn out files....I've never come across that but I can see why people would have modified them in days gone by before a tool catalogue on every website etc.

No they are definitely early but "proper" turning tools.  Henry Taylor and Robert Sorby mostly...maybe a record or two.  All made in Sheffield, the heart of what was once the British steel industry....mostly gone now except for some specialists.

I'll take some snaps and post them and you can see the stat of the bevels yourself :-)
Best.    Rob.

Offline Rob

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Re: Skew chisel grinding.....was a grind!
« Reply #33 on: June 14, 2013, 10:50:56 am »
Here's some rather appauling pics but will hopefully convey what I'm babbling on about.

Best.    Rob.

Offline Rob

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Re: Skew chisel grinding.....was a grind!
« Reply #34 on: June 14, 2013, 10:51:23 am »
Best.    Rob.

Offline Rob

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Re: Skew chisel grinding.....was a grind!
« Reply #35 on: June 14, 2013, 10:51:44 am »
Best.    Rob.

Offline Rob

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Re: Skew chisel grinding.....was a grind!
« Reply #36 on: June 14, 2013, 10:55:46 am »


This ones rubbish...it was trying to show how I've free-handed the bevel enough to create a micro bevel just on the edge of the edge (excuse poor grammar).

The notes on the shank help me to position it using the usb without a jig so I can get some consistency.  You know I'm constantly surprised and rewarded by how accurate an eyeball'd measurement can be.  I appreciate this isn't a neat and tidy bevel but the edge is easily straight enough for practical purposes with the job in hand.  I guess that chap trying to plan his curly maple has an altogether different problem in terms of the job in hand.  The trick is to create an edge which is fit for purpose I guess depending on what you'll use it for.
Best.    Rob.

Offline Rob

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Re: Skew chisel grinding.....was a grind!
« Reply #37 on: June 14, 2013, 10:56:36 am »


Slightly better but not much...should have used a white background
Best.    Rob.

Offline Rob

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Re: Skew chisel grinding.....was a grind!
« Reply #38 on: June 14, 2013, 10:57:59 am »


OK...though out of focus, you can see the micro bevel clearly now.  So this is one I've done. Next up is a monster that doesn't even have a handle...that I haven't done...gotta be nearly 2" wide
Best.    Rob.

Offline Rob

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Re: Skew chisel grinding.....was a grind!
« Reply #39 on: June 14, 2013, 11:00:20 am »


This is the big one...you can see that Dad (around 30 years ago) last did it with a stone I gues....bevels all over the place. That's one I'd like to regrind completely...preferably using the BGM-100 on a Norton or equivalent 46 type grit stone.  And to that end I'm getting a 2nd hand record 6" grinder this weekend for not much
Best.    Rob.

Offline Ken S

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Re: Skew chisel grinding.....was a grind!
« Reply #40 on: June 14, 2013, 12:23:12 pm »
Rob, You have a labor of love ahead of you.  I had the same pleasure restoring my grandfather's 1891 Stanley jack plane.

You might enjoy this book:

http://conoverworkshops.com/store/merchant.mvc?Screen=PROD&Store_Code=CWOS&Product_Code=4345&Category_Code=HS8

I have taken many classes with Ernie Conover over the years.  You may remember the Conover lathes.  Ernie and his father designed and built them.  He is also a fine teacher and a no slouch woodworker.

Best of luck with your restoration.  Keep us posted, and let us know what you think of the Norton 46 grit wheel.

Ken

Offline Ken S

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Re: Skew chisel grinding.....was a grind!
« Reply #41 on: June 17, 2013, 03:20:42 am »
Rob, as promised, I tried grinding on a metal lathe bit with my belt grinder and the dry grinder with the Norton 3X 46 grit stone.  i'm not exactly what alloy the lathe bit is, but it's a fairly certain bet than it's at least M2 high speed steel.

The belt grinder did OK.  Normally for a project like this I would have used a fresh belt.  The belt was slightly worn.  i am convinced it would do a satisfactory job.

The Norton 46 grit stone did very well.  I used only moderate pressure.  I think you will like it.  As I stated earlier, my dry grinder is a 40 year old six inch Sears Craftsman.  it's probably very much like your Record.

I wonder if using the dry grinder with the 46 grit stone would speed up sharpening planer blades.  presumably one would need to remove nicks.  If the nicks were removed with the blade held at a right angle and some of the approximate bevel restored with the dry grinder, the operation could be completed on the Tormek. The dry grinder would have already done much of the "heavy lifting".

Ken

Offline Herman Trivilino

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Re: Skew chisel grinding.....was a grind!
« Reply #42 on: June 17, 2013, 05:15:45 am »
The dry grinder would have already done much of the "heavy lifting".

That's essentially the concept I use when shaping a badly worn mower blade or one that needs the edge angle reduced.  It saves time and frustration.

I find that if I switch back and forth between dry grinder and Tormek it keeps the edge from overheating.

« Last Edit: June 18, 2013, 04:16:28 am by Herman Trivilino »
Origin: Big Bang

Offline Rob

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Re: Skew chisel grinding.....was a grind!
« Reply #43 on: June 17, 2013, 10:12:41 am »
Thanks for that chaps.  Your posts have been really useful.  Well, I got the 2nd hand Record this weekend from a lovely wood turner chap I met on a different forum.  Another wood turner only about a half hour drive from me (love the Internet for connecting special interest groups like that).  I digress!

The dry grinder is a little gem...6" wheels, one white and quite friable and the other a pink O Donnell wheel which I think is tuned to HSS turning type tools.  No tool rests or eye guards but the motor is sound and the wheels are fine.  No idea what grit they are either because the chap who owned it had also forgotten.....the blind leading the blind so to speak :-)

Mounted it on a board to dampen vibration and clamped that to my bench.  I've got one of those little t bar diamond dressers now that Herman recommended yonks ago and I have to say they're brilliant.  Only paid £8 for it too...nice.

I offered up that big bad 2" skew that I pictured the other day....with the gnarly bevel and......it just ate it for breakfast!!  Fantastic.  It's great having spent so much time on the Tormek because you develop a sort of "feel" for how hard to present a blade.  I quickly found out that too much pressure or for too long starts the loss of temper (blueing) which of course the old T7 avoids completely.  Simply light pressure, side to side movement and frequent cold water bath dunks did it easily.  I improvised a wooden jig (rest at the right height and marked the shank of the tool for protrusion control).  Then just freehanded it.  Amazingly fast steel removal....what a difference!

So last night I ordered the BGM-100 and that sucker will be attached to the dry grinder by the weekend.  Then I may have another crack at the planar blades!!!!
I also like the idea you both discuss about squaring off a nicked blade until you reach the end of the nick...then change the angle to grind the bevel.  I've never done that but it just sounds intuitively a good way to do it.

In all cases....my plan is to shape on the BGM setup and sharpen on the tormek.  But I have to say...I'm extremely impressed with the speed of steel removal...was starting to think that was a holy grail...happy chap again :-)

Best.    Rob.

Offline Ken S

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Re: Skew chisel grinding.....was a grind!
« Reply #44 on: June 17, 2013, 11:36:03 am »
Rob,

I mounted my dry grinder on a board (3/4 standard plywood).  It now lives on a heavy duty metal shelf.  It is easy to pull it out and set it on a bench.  It is just as easy to return it to the shelf.  It's quite practical.

Make sure you wear good eye protection!!!! 

I'll put the wheel dressing in the Ashley Iles post in Hand Tool Woodworking.

The grit size should be included in the long alphanumeric description on the side of your wheels.

Good luck with your venture in Dry Land.

Ken