Struggling with sharpen plane blade after cambering

[Tony Wilkins]

With grinder at last installed on stand, cambered the O1 blade for my LV 5 1/4w. Grinding went well I think. Got the 8” radius I wanted. But I’m struggling with sharpening. In my LN jig I could get the middle but. In the corners, no matter how much pressure I applied, I count get on the stone. Tried freehand but with neuropathy I’m not the greatest to feel bevels. Edge just is t getting sharp.

Suggestions?

FWIW using king 1k & 6k water stones

[Derek Cohen]

Tony, I will take a stab at this, but recognise that I do this freehand (I only use a guide for BU plane blades).

First point - an 8" radius is quite strong, and I doubt that you will use more than the central third of the blade. This means that the outer thirds are going to go unused, and do not need to be as sharp.

Second point: David Charlesworth provided a model (don't think of it as a method) for cambering a blade in which he divided the blade into sections - hone the outer sections three strokes each .... etc. In your case, keeping in mind that you have an 8" radius and are not trying to create this from a straight edge, hone only the centre, and then "swipe" from the centre the remainder of the third on one side, and then repeat it on the other.

Thirdly: Use the guide as a pivot and don't try and run it back-and-forth. You are seeking to hone along the secondary bevel leading edge, which is a curve. If you want to additionally hone while moving the guide back-and-forth, that is okay, but the movement you are looking for is to polish on the curved leading edge. This is what I do freehand.

Finally: remove the wire on the back of the blade.

A thought about the King stones. I used these 20+ years ago, and the composition may have changed. If you create a slurry, the stone cuts more strongly. If you remove the slurry, you may get a finer polish.

Regards from Perth

Derek

[Jimmy Harris]

I'm not aware of a jig that'll work for cambered blades. Paul Sellers have a video about making a scrub plane and he shows two different methods to sharpen a cambered blade by hand. The figure 8 method he does is kind of difficult to master, but the other method he briefly shows might be easier if you haven't tried that. It's pretty similar to the method shown in the Lie Nielsen scrub plane sharpening video, but turned 90°, which also might be worth a look at. Either one of those would be a lot easier than Rob Cosman's method of going around in circles.

Otherwise the best thing I can think of would be to hollow out a channel into a piece of wood with the correct radius and glue some sandpaper to it. Then make a jig to hold the blade at the correct angle and run it back and forth. That sounds like a huge headache to me and hard to get right. So maybe send it off to a sharpening service?

Personally, I'd just keep practicing the free hand method and try it a bunch of different ways until you find what works best for you. It's a scrub plane. It doesn't need to be razor sharp.

[Tom M King]

I use an old Record guide that only has a ball under it. I can hone a Scrub plane iron with it. It's the red one in this picture just to show it but I'd never sharpen the narrow chisel with it.

Otherwise, the only other choice I know of is freehand. My helpers could sharpen the short radius cambers with the Record guide, but Zero chance by hand.

Just a note about King stones: I'm not familiar with the whole line, but I do have one 300 that doesn't require a slurry. I have no idea about the 1k and 6k in question.

edited to add: Here's a later version of the one I have.

https://www.ebay.com/itm/395102282805?hash=item5bfdee6435:g:owcAAOSwtQ9lWz3 J&amdata=enc%3AAQAIAAAA8KCsO32RJt%2BlvnEQ3m2EvHAxY8r %2FeAv%2BMUTQUZe%2BrR9LLn6eER6VuxJ1jBKZy5jmp7V62U8 rNV1C28phpHruGD3S%2FTqRuNU8Iu3pS%2FIcrPshjIAT8RfRM jRipc22N8STrmo0%2B6S3xyMqHGpIfdT3TkeARvL%2Bf7R4sD% 2BwBg6Ylo8gVEtfihx3w0ZyXgpXuxqjjpyrAfk65lr0RaYMI9N vx%2FPXUD%2Fi12MwFvp19SB1k7x8hEPggUsK532bFrzu8lBu1 K5PkmacSA8lSKIgsIqRKArhsA0ceIqCvJ6oI9qYGJjqNZPTqUp BcLss3Y85ccoe0A%3D%3D%7Ctkp%3ABk9SR8Tx8bubYw

[Tony Wilkins]

Tony, I will take a stab at this, but recognise that I do this freehand (I only use a guide for BU plane blades).

First point - an 8" radius is quite strong, and I doubt that you will use more than the central third of the blade. This means that the outer thirds are going to go unused, and do not need to be as sharp.

Second point: David Charlesworth provided a model (don't think of it as a method) for cambering a blade in which he divided the blade into sections - hone the outer sections three strokes each .... etc. In your case, keeping in mind that you have an 8" radius and are not trying to create this from a straight edge, hone only the centre, and then "swipe" from the centre the remainder of the third on one side, and then repeat it on the other.

Thirdly: Use the guide as a pivot and don't try and run it back-and-forth. You are seeking to hone along the secondary bevel leading edge, which is a curve. If you want to additionally hone while moving the guide back-and-forth, that is okay, but the movement you are looking for is to polish on the curved leading edge. This is what I do freehand.

Finally: remove the wire on the back of the blade.

A thought about the King stones. I used these 20+ years ago, and the composition may have changed. If you create a slurry, the stone cuts more strongly. If you remove the slurry, you may get a finer polish.

Regards from Perth

Derek
I use the DC method for smoothing and jointer blades but this seemed to be too severe for that. I think the wheel on the LN guide is too wide to get the pivot all the way to the edge with that radius. I’m using that much of a radius because I’m planning to use it as a traditional fore and rough work. Felt what I thought was a wire edge but when I took it off the edge was still not sharp.

[Tony Wilkins]

I have a vague recollection of the Paul Sellers video you’re talking about. I’ll go find it. The 90* thing is what I was trying at the end and felt the best but the cutting edge just wasn’t sharp.

[Derek Cohen]

Okay Tony, I recalled a guide I built many years ago as part of "The 10c Sharpening System". https://www.inthewoodshop.com/WoodworkTechniques/The%2010%20Cent%20Sharpening%20System.html

It looks like this ...

https://www.inthewoodshop.com/WoodworkTechniques/The%2010%20Cent%20Sharpening%20System_html_1c8b323 8.gif

Designed by Brent Beach ...

https://www.inthewoodshop.com/WoodworkTechniques/The%2010%20Cent%20Sharpening%20System_html_m3eaaf5 aa.gif

It is just two pieces of wood screwed together.

The scrub plane modification would be to saw the bottom to a Vee to act as a pivot, or shape a camber there. Even a nail below would work - just run it on a scraper blade.

What made me recall this was this "upside down" method I used for the LV Mk 2 before Lee Valley produced a cambering kit for this guide ...

https://i.postimg.cc/FzkCn1tj/Advanced_Angles_on_the_Lee_Valley_Honing_Guide_Mk_ II_html_m6069c322.gif (https://postimages.org/)

Regards from Perth

Derek

[Tony Wilkins]

Okay Tony, I recalled a guide I built many years ago as part of "The 10c Sharpening System". https://www.inthewoodshop.com/WoodworkTechniques/The%2010%20Cent%20Sharpening%20System.html

It looks like this ...

https://www.inthewoodshop.com/WoodworkTechniques/The%2010%20Cent%20Sharpening%20System_html_1c8b323 8.gif

Designed by Brent Beach ...

https://www.inthewoodshop.com/WoodworkTechniques/The%2010%20Cent%20Sharpening%20System_html_m3eaaf5 aa.gif

It is just two pieces of wood screwed together.

The scrub plane modification would be to saw the bottom to a Vee to act as a pivot, or shape a camber there. Even a nail below would work - just run it on a scraper blade.

What made me recall this was this "upside down" method I used for the LV Mk 2 before Lee Valley produced a cambering kit for this guide ...

https://i.postimg.cc/FzkCn1tj/Advanced_Angles_on_the_Lee_Valley_Honing_Guide_Mk_ II_html_m6069c322.gif (https://postimages.org/)

Regards from Perth

Derek

I do have a mk 2 with camber roller. Not my favorite guide but I could try it if it will work?

[Derek Cohen]

Tony, try the Mk2. Remember, you do not need to hone more that the centre third of the leading edge since there is already a steep camber.

Regards from Perth

Derek

[Rafael Herrera]

Tony, an 8" radius is quite extreme and, as Derek pointed out, in production you're more likely to only use the middle third of the blade.

I'm guessing here, but if your neuropathy makes it difficult holding the iron when free hand honing, a contraption like the one shown in the picture might help. I actually use that block to abrade the flat side of irons when I refurbish them. The block is out of a 2x4 off cut. It doesn't need to be that big, just big enough for a comfortable grip.

513291

[Rafael Herrera]

This is my scrub plane and its iron.

The scored line on the bench is an 8" radius arc. My camber radius if longer than that.

I don't do a lot of rough planing, but when I do this plane is plenty aggressive for my taste.

My guess is that, unless I'm planing green wood, I might cause damage to the board if I try to plough through with an 8" camber.

513293513294

[Derek Cohen]

I would call an 8" radius on a scrub plane "moderate" since the typical radius on a Stanley #40, the LN and Veritas scrub planes are 3" radii - that is "severe"! These blades are also only 1 1/2" wide. 8" would be a "severe" radius on a jack plane. I found, as Rafael pointed out, that this is too great for the hardwoods in my location, cutting too deeply to avoid great tearout. Consequently, my jack uses a 10-12" (closer to 12") radius.

Regards from Perth

Derek

[Bob Jones 5443]

I’ve no need for an 8” radius, and don’t know what such a need might be. For typical flattening and smoothing — about all I use hand planes for — I’ve found the David Charlesworth sharpening and cambering method produces excellent results, surprisingly quickly, easily, and reproducibly (and the 1/2” wide wheel on the Eclipse guide enables fine edge control).

And cheaply: I don’t go in for honing guides or systems that cost over a hundred dollars. The Eclipse and its Taiwanese imitators fit the bill nicely. David was always a parsimonious fellow himself, one of many reasons I admire him.

[Tony Wilkins]

I’ve no need for an 8” radius, and don’t know what such a need might be. For typical flattening and smoothing — about all I use hand planes for — I’ve found the David Charlesworth sharpening and cambering method produces excellent results, surprisingly quickly, easily, and reproducibly (and the 1/2” wide wheel on the Eclipse guide enables fine edge control).

And cheaply: I don’t go in for honing guides or systems that cost over a hundred dollars. The Eclipse and its Taiwanese imitators fit the bill nicely. David was always a parsimonious fellow himself, one of many reasons I admire him.
Does it work for you on very rough sawn boards? It’s my preferred way for pre planed lumber but figured it would be too slow for the rough stock and uneven panels I’ve been working on.

[les winter]

LeeValley to the rescue! I own this and use it for scrub plane blades and compass plane blades. Works perfectly for this task.

https://www.leevalley.com/en-us/shop/tools/sharpening/guides/114954-lee-valley-replica-honing-guide?item=15M1001

[John Erickson]

Turn that blade 90* to your stone, use your fingers to hold the blade flat on the grind of the cutting edge, start at the right corner of the blade go forward and roll the blade the same time. I'm right handed.

[Tom M King]

That LV guide looks good if the blade you need to sharpen has a slot. My Scrub plane doesn't. The Record 161 works like a charm with it, as well as short radius cambered jack plane irons. There always seem to be some for sale in the UK on ebay, but I don't know that I've ever seen one here. Mine came from the UK back when a small packet was 5 or 6 dollars to ship.

[chuck van dyck]

I was just honing the iron on my #40 yesterday. I am in the middle of getting a 96x24 cherry slab flat for a credenza commission. Unfortunately my planer maxes out at 20”.

I free hand but I find it helpful to hold both stone and iron and bring them together that way. So hold iron in non dominant hand, and use your dominant hand to control the polish. Since you don’t mind grinding it really doesn’t matter how perfectly you are registered to the bevel. Any inconsistency will be ground away next time you need to grind. Get get the stiffest buffing wheel you can find and put it in a drill. I use a 4” ryobi from hd. Get it nice and broken in with compound and touch up the polish as needed.

Sounds to me like you still haven’t hit the edge. Probably the back still needs some work.

[Tony Wilkins]

I’m wondering if I need a stone more coarse than 1k?

[steven c newman]

Since the OP is using C. Schwarz as a guide to flattening boards with a plane...also in that Woodwright's Shop show...they show HOW to sharpen that 8" radius....may want to go back and take a look? "Handplane Essentials" is the episode, I believe....

Just a thought...

[Bob Jones 5443]

Does it work for you on very rough sawn boards? It’s my preferred way for pre planed lumber but figured it would be too slow for the rough stock and uneven panels I’ve been working on.

In my shop, that’s what the jointer and planer are for. The hand plane — almost always the 5-1/2 — whisks away the machining marks and dials in precise dimensions. Certainly, in a shop without the luxury of those machines, we need the plane to do more. So I guess I ask less of my planes than some.

I can also imagine an application where you want the finished board to retain some rough texture for aesthetic purposes. Then it would be good to have a scrub plane. My work is more conventional than that.

One might want a scrub plane for rough wide slabs, too, of course. I rarely work with them. When I flattened my birch bench, I just used my 607, but the surface was just wavy, not very rough.

[les winter]

513329513330

No slot? No problem. This gadget is called a ball transfer. Readily available and cheap.

[Jim Koepke]

No slot? No problem. This gadget is called a ball transfer. Readily available and cheap.

Also known as a ball caster.

jtk

[Tony Wilkins]

Haven’t been back to it. Just using the LN blade in my smoother. Not ideal but a good lazy solution.

[Ted Calver]

For those with a Tormec, this (https://www.youtube.com/watch?v=uFnHfHLjKbk) just popped up on my YouTube feed. Shows sharpening of blade for Stanley No 40.

[chuck van dyck]

Haven’t been back to it. Just using the LN blade in my smoother. Not ideal but a good lazy solution.

taking the path of least resistance isn't lazy. you just wanna make something. tools work for you, not the other way around. I use whatever I have however needed to get a job done. Some specialty jig is only gonna take up space. I believe CS would approve of this tactic.

[Tony Wilkins]

For those with a Tormec, this (https://www.youtube.com/watch?v=uFnHfHLjKbk) just popped up on my YouTube feed. Shows sharpening of blade for Stanley No 40.
I’ve wondered if I should have gotten a Tormek instead of the grinder. Are you trying to feed my TAD?

[mike stenson]

I have both, my tormek sits under a bench 99.99% of the time.

It's great for turning tools, but I don't use it for planes. It's way too slow.

[Tony Wilkins]

About to bring the top in the house (if the wind cooperates). It’s not perfectly flat on the bottom but it’s close. The traditional folks (CS, M &T, Folsanbee, Cherubini) talk about how rough secondary surfaces are. I think I’m at that point. I’ll look at it again once it’s been inside the house a while for twist, movement, etc. it’ll be cut down in length anyway.

[steven c newman]

As noted elsewhere...stand to the side of your oil stones...lock the tool in place by locking your arms tight to your body.....use your hips to generate the movements...and move in a Figure Pattern to sharpen a Cambered edge.....Schwarz uses Olive Oil....I use 3in1 oil....Place the plane iron back into the plane...sharpen again in..maybe a year?


I use a Great Neck Corsair C-5 as a scrub-jack....been in use for several years now....been sharpened twice...once when I bought it, and once 2 years ago...8" radius. Chip breaker is set to the edge of the irons corners...no, I don't need it radiused to match the iron's camber...not needed.

A few years ago...I needed a glue up of Ash planks....3/4" x 16" x 54" to make to the of an Entertainment center....C-5 Scrub Jack flattened the panel, leveled the high spots down to flat...then the panel was smoothed with a #4 Stanley....YMMV, of course..

[Jim Koepke]

On an episode of The Woodwrights Shop, Mary May shows a technique for sharpening carving gouges.

It is similar to what Steven describes @ > https://www.pbs.org/video/carving-away-with-mary-may-tioglz/ < it is at about 14:30 minutes in. It also works well for me on cambered blades.

An 8" radius on a 2" blade should be about 0.063" at the center if my math is correct.

Actually if the math was done correctly here > https://www.handymath.com/cgi-bin/arc18.cgi?submit=Entry

513467

That is a lot of wood to hog out if the full width of the blade is to be used. It is the reason most scrub planing only uses the center of the blade.

Three of my planes are set up as scrub planes and another can become a scrub plane by simply changing the blade.

513468

From left to right the blades are for a #5, a #5-1/4 and a #40. Not shown is a blade for a #5-1/2.

At one time it seemed like a scrub plane wouldn't be of any use in my shop. Then one day playing with a beat up #5-1/4 impressed me so much it seemed a good idea to convert some of my extra plane bodies. The #40 was offered by one or my favorite local tool sellers at a price I couldn't refuse.

jtk