Grinder for Cambering Irons? Rikon?

[Erich Weidner]

I just bought a Rikon 8" low speed grinder (1/2 hp) from woodcraft. I really got it to camber my #5 jack plane (blade) which should arrive in a few days.
Random googling has various people saying it is under powered, to just fine.

Do I need different wheels from what come with it to do an 8-10" camber on this? (I'm looking at C. Schwarz videos/articles and want to give a cambered iron a try. I've always just eased the edges of plane blades previously).

[Frederick Skelly]

Hi Erich,
I have that grinder with a cbn wheel. It's fine for chisels and plane irons. I havent tried to grind a heavy camber, but I dont see why that would be a problem with the "stock" wheels.
Fred

[Jim Matthews]

Derek Cohen illustrates an effective method using a wide belt sander and hardwood template.

http://www.inthewoodshop.com/Woodwor...aneBlades.html

I saw Phil Lowe demonstrate the process on a traditional grinder (plain Jane white AlOx wheel) but it was with fairly thin carbon steel blades. Phil's technique employs a Sharpie marker and some measure of skill.

See 4:10 in the first video for the basics and a brief illustration.

https://www.finewoodworking.com/2007...andplane-blade

[James Pallas]

I've ground lots of steel over the years. Here's my take.
1) speed of the grinder makes little difference
2) wheel grit makes a lot of difference (just like sandpaper)
3) grinding is not a forceful excercise
4) if your object gets too hot to touch you are going too fast (be gentle, take your time)
5) mark your objectives fluid, sharpie so you have a goal to shoot for
6) practice, practice, get some mild steel bar and try it until you are comfortable
7) grinders are for rough work, like a scrub plane or a jack
8) sharpening grinders, Tormek etc. are for refining
My current grinder is an older Ingersoll rand (Baldor). It had a 36 grit and an 80 grit wheels until recently. I bought a CBN wheel for it. It leaves a nicer finish which is easier to refine on stones. I left the 36 grit standard grey wheel on it and start there usually for changing bevels or fixing damage.
if you can touch it without pain your okay, be gentle like the proverbial baby bird. No need for speed you are not going to do this often unless you are refurbish a lot, making tools, or are being ham fisted with your cutting tools.

Jim

PS If I really want to get rough and don't care about heat I have an angle grinder for speed. Now that will get you in trouble quickly. Same rules apply though, you can finess an angle grinder too.

[steven c newman]

In the Woodwright's shop episode, "Hand plane essentials w/ C. Schwarz" Roy learns how to mark and grind and sharpen a #5's iron into a camber....8" radius. Might be worth a looksee over on youtube? In fact, the entire episode is helpful....

Real fancy, high-tech grinder in use, too...
413119413120

[Barney Markunas]

I wouldn't obsess over this too much. You're planning to adjust an iron or two, not do this on a production basis, right? Does it really matter if you don't have the most powerful grinder in the world? Probably not. Do you need the very best wheels on the planet (whatever that means?) to do what you are doing? Definitely not.

You will be fine. Practice a little before you work on your brand new blade. If you don't have any scrap steel around, think about giving your lawnmower blade a little touch up. Once you have some sense of what you are doing, mark out your waste, take your time, and trust your fingers. If the blade that is coming is something upscale (e.g. Hock or LV, etc) think about putting the camber in the stock blade that came with your plane and save the high dollar steel for when you are a little bit farther along your learning curve.

It is not hard to blue an edge if you are in a hurry and not paying attention. But using any grinder you need to be paying attention anyway - safety first. Wear some eye protection, make sure there isn't anything loose nearby that might be caught by a wheel, and don't grind on the side of the wheel unless you are sure your wheel is designed for those kinds of loads. Catastrophic failure of a wheel is not something you want to experience first hand.

It is a bit tougher to put the steel back on so start gradually. Consider starting with a bit less camber and see what you think. It is easy enough to take off a bit more steel later f you decide you'd prefer something more aggressive. Remember, this is for a jack plane. Don't let perfection get in the way of good enough.

Enjoy your new tools and when in doubt, dunk.

[Brian Holcombe]

I have a 1/4hp Baldor with a CBN wheel, the power of the grinder never really comes into play because you can't lean into a hardened piece of steel without ruining the temper, even with a CBN.

[Tom M King]

Since you'll be doing a Jack plane iron to start with, typically 8 to10 inches of radius, it's a good time to learn what you need to do to keep from bluing a corner. When the corner blues starting with a straight iron, it won't matter if the corners get a touch of blue, since you're going to grind away a lot of those corners anyway. Try not to blue a corner to start with, and when you do, try not to next time, and the next. It's really an acquired feel. By the time you get half way to where you're (I hate it when lazy people type your for you're) going, you should be able to get there without getting any part of it too hot.

[Tom Trees]

Is it me, or does grinding your cutting irons in winter, tend to be less forgiving than in summer?
I haven't blued my steel in a while now, although it could be possible that the cheap wheels what came with the machine are more aggressive now,
compared to when they were new.

Could this be because of possible glazing from not using water?...
I will not grind now, without a jar of water within inches of the machine.

Tom

[Erich Weidner]

I don't have any steel laying around (and no lawn mower anymore). The new #5 is a LN and should be here on Friday. (Yey!)
My old #5 (a modern English made Stanley) the screw for the front handle broke (inside the plane. Not sure if that is an example of current Stanley's being "junk", but trying to get that broken shaft out is going to be a challenge). I guess I can practice on that blade before I try my hand on the new LN blade.

[James Pallas]

I don't have any steel laying around (and no lawn mower anymore). The new #5 is a LN and should be here on Friday. (Yey!)
My old #5 (a modern English made Stanley) the screw for the front handle broke (inside the plane. Not sure if that is an example of current Stanley's being "junk", but trying to get that broken shaft out is going to be a challenge). I guess I can practice on that blade before I try my hand on the new LN blade.

Good plan. Gently, slowly, mark before you start. Good luck.
Jim

[Jim Matthews]

FWIW - At one point I approached a curved camber as a necessity. What I really wanted was to avoid "tracks" left on the surface at the side of each cut. I consider cambering to be an advanced skill that requires more tools andtime than I can afford. Sharpening is a task - woodworking is a pleasure.

I now emulate the shape at traditional Japanese plane blades and knock off the corners of plane irons.

Today (after ten years of fumbling about) the only cambered iron I have is a scrub plane, which removes stock in a hurry.

The following video shows a dead simple way to do this.

https://blog.lostartpress.com/2019/0...-a-plane-iron/

[justin sherriff]

The following video shows a dead simple way to do this.

https://blog.lostartpress.com/2019/0...-a-plane-iron/ link not working for me
Is this what you had
Round the Corners of a Plane Iron
https://blog.lostartpress.com/2019/01/16/round-the-corners-of-a-plane-iron/

[Eric Danstrom]

I use a Veritas honing guide with chambered roller for this function.

[Jim Koepke]

My thoughts on blade camber have evolved over the years. Especially since recently a couple pieces of wood benefited from the use of planes with irons cambered to use as scrub planes.

Here is a post on that:

https://sawmillcreek.org/showthread.php?272588

The scrub planes and cambered blades are in post #23.

Here is an old post on another way to 'camber' a blade:

https://sawmillcreek.org/showthread.php?158373

Derek Cohen has sharpening posts on his website > inthewoodshop.com < which include cambering a blade or two if my memory is working.

Another thought that comes to mind is if your stones are worn a bit in the middle, it will automagically camber your blades.

jtk

[Jim Matthews]

That's the one.

[John Stevens]

automagically

jtk
Love it. . .