Thread: Rob Cosman

No experience of them myself, but Jim Davey sells them and may be able to comment for you.
See:
Jim Davey - Planes and Sharpening - BLADES / IRONS for Sale: STANLEY, IBC Pinnacle A-2 Cryo & ACADEMY M2 HSS Replacement Irons for Sale
Cheers
SG

I just checked some shavings I took today with an Academy blade fitted to a Stanley #6. They were 0.02mm, 0.00078". With a bit more care sharpening there might be a bit more in it too. So yes, good blade.

Cheers
Michael

With correct sharpening technique, most modern thick A2 or M2 blades will achieve these results. I have no trouble doing this with Veritas planes, but as Rob Cosman says, they aren't cheap.

The real advantage of the blade/chipbreaker combo he is promoting is that it has been purpose designed to "up-blade" a cheaper Stanley or Record plane, i.e. it fits, and it works out of the box.

By way of comparison, I modified my very first (craptacular quality) Record No.5 to get the same results using a heavy Clifton blade and chipbreaker, but along the way I had to make custom parts, file bits off things to make them fit, etc. I ended up where I needed to be, but only after lots of stuffing around. If I had to do it again, I'd definitely just go for a "drop in" A2 blade/chipbreaker solution such as Rob Cosman describes.

If you don't tune it, no matter what blade and cap iron you drop in, it's not going to perform like in the video. So if you spent that much tuning your Record wasn't wasted. Even if you got Cosman blade/cap iron set, you would have needed to anyway.

Once fettled, cheaper alternative, like Hock or Lie Nielsen cap iron and blade set will perform just as well and they will drop right in, too. So I don't really think there is anything special about Cosman set.

Thanks, fellas for your thoughts.

I thought that Derek C. had responded but now I can't find his post!! Was I seeing things?

These are a super blade and coupled with the Cosman Cap Iron they are even better. The adjustable tabs at the rectangular slot in the Cap Iron allow for the extra thick Iron and reduce that annoying backlash usually associated with thick Irons. They are A-2, 60-62Rc, double tempered and cryo treated, very well finished and have the correct width slot so that there is not too much lateral backlash.
I have a few Irons in stock and a fresh batch arriving within a week, including the new IBC/Cosman Double Iron - have a look at my site for details.

Take care and Stay Sharp,
Jim

Originally Posted by Tiger

Thanks, fellas for your thoughts.

I thought that Derek C. had responded but now I can't find his post!! Was I seeing things?

I did reply, but deleted it. No, I did not say anything disparaging about Rob Cosman, whom I like and whom I've chatted to on a few occasions.

I very much like the little add-on for the cap iron he is manufacturing. This will open up the opportunity for many old Stanleys and Records, etc to use thick blades (not because of limitation of the mouth but because of the adjuster). While he has patented this idea, I am sure I have seen it in use on planes in the past, and I know I (for one) have considered building and using this gizmo in the past as well. Nevertheless, no one was/is making it, and I like the concept.

On the other hand the blade steel, while sounding very good, is probably no better/different than the LN, LV (especially) and Hock. What is different is the thickness of the steel (assuming that the blade is thicker), and here I would say that the standard LN blade is probably the same as this one.

At the end of the day you have to sharpen the blade. The blade alone does not produce a miracle. More importantly, I would like to see Rob planing a interlocked hardwood, not the straight-grained softwood he was using in the demo (which is not a test of anything at all!).

Regards from Perth

Derek

The Blades that Derek has mentioned are just about the same - A-2, over 60Rc, 2.45mm or thicker - except the Veritas and Lee Valley aren't cryo treated.

Take care and Stay Sharp,
Jim

Thanks for the further suggestions.

My experience is that I can get my blade razor sharp and it will cut thin shavings but not to the extent that Rob produces. I also find that the razor sharpness doesn't last long and I need to touch it up regularly to maintain the thin shavings. With a chisel that's no big deal, with a plane iron, it's more work as you have to disassemble. On top of that, there is a little bit of chatter with my plane (which is a Pope no. 4) and maybe that affects the quality of shavings.

Derek, I'm glad you made the point about the quality of timber being used in the Cosman demonstration as when I saw it, I thought wow and why can't I achieve that.

With a correctly tuned regular plane (Stanley, Pope etc.) and well sharpened and with the right bit of wood, can you produce less than a thou shavings?

Originally Posted by Tiger

With a correctly tuned regular plane (Stanley, Pope etc.) and well sharpened and with the right bit of wood, can you produce less than a thou shavings?

Yes you can but it doesn't last as long as the Super Blades. The A-2 Blades are usually 60-62RC whereas M2 is usually tempered to 62-64Rc - the A-2 gets to brittle if harder than 62Rc. M2 HSS is tougher than A-2 High Carbon steel and will hold its edge longer. Downside is that M2 is tougher to grind and hone.
You can put an edge on anything, even the Victory Irons from Stanley during WWII when they couldn't get Sheffield steel, but it doesn't last long.
I find the A-2 relatively easy to hone and with good edge retention.

Take care and Stay Sharp,
Jim

Originally Posted by Tiger

Thanks for the further suggestions.

.... Derek, I'm glad you made the point about the quality of timber being used in the Cosman demonstration as when I saw it, I thought wow and why can't I achieve that.

With a correctly tuned regular plane (Stanley, Pope etc.) and well sharpened and with the right bit of wood, can you produce less than a thou shavings?

Tiger, as Jim notes, the advantage of a good blade is that it holds an edge longer. However it is generally always a balance between edge-holding and ease of sharpening. Here in Oz we tend to lean towards edge-holding since our timbers are so abrasive (compared to the USA, for example).

Also do not confuse edge-holding with improved planing performance. Sure, a sharp edge will plane better, but our interlocked timbers requyire more than simply a sharp edge. They require a high cutting angle as well. Adding a thick and sharp blade to a Stanleyt plane works well for moderately hard timber but add interlocking grain and I bet there will be as much tear out as with any other blade that is sharp. That is why we have the HNT Gordons and the BU planes - they offer high cutting angles to go along with sharp edges.

What can you do with a sharp edge on soft wood? Gee, just about anything. Here is a $5 block plane from Bunnings ...



The Orange Block Plane – a review

And a 10 foot shaving with a standard angle Mujingfang on pine ...



... but can you plane like with on hard, interlocked Jarrah? ...



Regards from Perth

Derek

Thanks, Derek for that explanation. I haven't ventured into the high-end planes yet, I have a number of Pope, Record and Stanley planes most of which I have reconditioned as I enjoy that sort of thing. I don't use much hard timber except for Blackwood which is prone to tearout with my planes no matter how sharp the blade is. As I have a number of planes, I could grind a high cutting angle on one of the blades if that would help, what is an appropriate angle, bearing in mind that I'd still be using the same thin blade.

Hi Derek, the wood I was using in the youtube clip is not a soft wood, it is yellow birch, about as hard as eastern Maple. Can be a bear to plane however this pc was nice and straight. That said, in my new DVD that comes free with IBC/Woodcraft blades, I use pine as well. My reason is to allow the new guy an opportunity to develop his/her technique before having to apply the extra muscle.

To the chap that commented about dropping the blade in the old Stanley/record, you do need to do a bit of fixing. The advantage of the DVD is to show you some quick processes that prevent you from having to reinvent the wheel. Total time on most #4's is under an hour. I use a file, screwdriver, flat surface such as a jointer table, float glass or table saw top, sticky-back sand paper, feeler gauge and a bench vise. Most hobby shops would have all of this. The DVD has an 8 page downloadable pdf so you can print off shop notes after watching the process on TV.

Final note, dealing with figured wood is a challenge. Plane has to have a flat sole, the blade has to be held firmly and it goes without saying it has to be sharp. As I have travelled around teaching in three countries I am surprised at how few actually know how to sharpen. A few years ago while doing a seminar in England, David Charlesworth was in the audience and he confirmed what I just said, very few know how to sharpen. The next two criteria are pitch and throat size. You can’t do much to change the pitch on the old planes but you can adjust the throat and with a bit of effort make is parallel to the blade and really tight (this is why the sole has to be flat). The trailing edge of the sole just ahead of the blade provides downward pressure on the fibers preventing them from lifting up as grain direction changes. To alter the pitch or angle of attack, play around with a back bevel, I suggest having a separate blade for this. Perhaps it is time for a youtube video planing figured wood with an old Stanley and new IBC blade/breaker, see if we can’t make some folks happy.
Enjoy your shop time!
Rob Cosman

Thanks for dropping by.

Nobody can sharpen? Really? There's so much information available on sharpening. What's missing?

Not that I'm the world's best sharpener or anything.......