Page 1 of 2 12 LastLast
Results 1 to 15 of 17

Thread: Cosman Blade

  1. #1
    Join Date
    Nov 2008
    Location
    New Jersey
    Posts
    103

    Cosman Blade

    Guys, here is a pic of my Frankenplane. Its a Bailey #5 with a Cosman blade which I finished sharpening and honing. Now have get it to fit this plane. I found a video by Rob Cosman that says you have to file the throat to get a proper fit as the blade and back iron are so much thicker actually over twice as thick as the original ones. In the video he never says how much to file that heard or saw.
    Has anyone done this type of retro fit and is your throat opening beyond .260 inches? In the pic of the throat and blade the back of the blade is bottomed against the sole of the unit and the blade is still not projecting. I have a small amount that I can still move the frog forward and try to bring the blade thru again but it would most likely hit the front edge. Just want to ask b4 I take away too much material. Any thoughts advice welcome.

  2. #2
    Join Date
    Mar 2003
    Location
    San Diego, CA
    Posts
    317
    I haven't done it myself but have a friend who had to increase the opening by 1/8" on a Bailey #5 before his blade projected. That convinced me I didn't need a Cosman (IBC) blade.

  3. #3
    Join Date
    Nov 2008
    Location
    New Jersey
    Posts
    103
    Greg is there any chance your friend has a set of calipers and could give me an idea of how big it should be?

  4. #4
    Personally, I would pass on any product that required that much modification of a tool. Hock and Lie-Nielsen both make Stanley replacement blades that are direct fits, without modification. I found them to offer significant improvements in planing performance and edge retention. The Hock blades are easier to hone. The Cosman products promise a lot and cost you a lot, but much of their performance comes from the hand and eye of Mr. Cosman. An example: The plane irons that cost a premium because they were personally honed by him. If he will drop by weekly to refresh those edges, it might work out to be a fair deal. Otherwise you end up with a dull blade that you ​will have to hone yourself.

  5. #5
    Join Date
    Sep 2007
    Location
    Longview WA
    Posts
    27,437
    Blog Entries
    1
    Howdy Pat,

    Your pictures didn't come through.

    As far as setting the frog is concerned, it should be set forward so the bed of the frog and the back of the mouth are aligned.

    If the mouth needs to be filed, only enough to allow shavings to pass needs to be removed.

    jtk
    "A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
    - Sir Winston Churchill (1874-1965)

  6. #6
    Join Date
    Nov 2008
    Location
    New Jersey
    Posts
    103

    Found bigger problem!!!

    Well after thinking for 2 hours that the blade was bottoming out on the shoe of the frog, it turns out it s hitting the cap iron retention screw and won't allow it to protrude far enough even with the frog beyond the base of the throat. Will be on the phone to Mr. Cosman REALLY SOON. This is just not right. Like Mike said the amount of work to fit a new blade (which by the way in his YouTube channel videos says it works) is just ridiculous. Now to solve this I would have to grind the hole in the blade and cap iron into an oval to allow it to pass further forward. I don't own machining equipment to work on tool steel.

    INFO: I spoke to Rob and it turns out that they make the blade in 2 different configuration, actually the chip breaker. One came with a round hole and one came with an oval version. He said that there were many variations of Stanley #5 and some worked with round holes others did not.

    cosman #5 plane.jpgcosman #5 plane throat. jpg.jpg
    Last edited by Pat Meeuwissen; 10-03-2015 at 7:59 PM. Reason: Spoke to Rob:

  7. #7
    Quote Originally Posted by Mike Brady View Post
    Personally, I would pass on any product that required that much modification of a tool. Hock and Lie-Nielsen both make Stanley replacement blades that are direct fits.....
    I agree with Mike. Suggest you return the iron if possible. LV also makesca very nice replacement blade and chip iron. Put those in my own #5 restoration and they work lovely.

  8. #8
    Join Date
    Feb 2004
    Location
    Perth, Australia
    Posts
    9,492
    Hi Pat

    There are a couple of illogicalities here.

    Firstly, a #5 Bailey is generally used as a jack plane, which means that it is a coarse tool. This involves a strongly cambered blade (typically around 8" radius) and a wide open mouth. So, opening the mouth should not be an issue - it needs to be wide enough for thick shavings.

    Secondly, the blade is totally overkill for such a plane. It is a expensive blade that one would consider for a smoother, rather than a muck-about coarse plane. I think that a thicker-than-Stanley blade is better, but there are others to choose from.

    Thirdly, the blade was designed before the chipbreaker came back into fashion as a means of controlling tearout. Should you choose to use the #5 as a smoother (in my opinion it is too long for this task), then you would need to open the mouth wider anyway to allow shavings to pass by a mouth blocked by the chipbreaker.

    Personally, I would find a nice Stanley #4 and put this blade in that. Both the #4 and #5 are so cheap that you could screw them up and find another. It is possible that you could finish with a magnificent #4 (with the Cosman blade), and a fantastic #5 (with a LV or Hock blade).

    Regards from Perth

    Derek

  9. Over thick blades are just more steel to grind away when sharpening. I'm sure cosman's blades are quality steel, but the thickness is totally unnecessary. The Bailey pattern plane was designed for thin blades, have worked perfectly with thin blades for 150 years and will continue to work perfectly for far longer than you will be working wood.

  10. #10
    Quote Originally Posted by bridger berdel View Post
    Over thick blades are just more steel to grind away when sharpening. I'm sure cosman's blades are quality steel, but the thickness is totally unnecessary. The Bailey pattern plane was designed for thin blades, have worked perfectly with thin blades for 150 years and will continue to work perfectly for far longer than you will be working wood.

    That's known as cutting to the chase .

    ken

  11. #11
    Join Date
    Aug 2013
    Location
    Renton, WA
    Posts
    228
    For all of you that think this is not a good idea I did install a Cosman blade and chipbreaker in a no. 6 that I own. Yes I did have to modify the mouth of the plane to get the blade to work but after filing and fitting the blade I have a awesome heavy Stanley 6 that cuts .001 shavings and works much better than it did before I swapped out blades. I like a heavier plane. I am glad I made the conversion and think that if you need a heavier iron in a Stanley plane it is a reasonable conversion. Not hard to do at all.

  12. #12
    Pat,

    I put an IBC Cosman blade and C/B in an old no 5 and wrote about it in F&C. My memory says about 1 mm was filed from the front edge of the throat. Final width about 15/64".

    This filing work is easy, with a little marking out and care!

    I have almost all my no 5 & 5 1/2 planes tuned up as smoothers because I have planing machinery in my shop. I am generally just refining or perfecting the machine results.

    I think you will like your plane a lot.

    David Charlesworth

  13. #13
    Join Date
    Jan 2005
    Location
    Milton, GA
    Posts
    3,213
    Blog Entries
    1
    Interesting thread. Derek, as is always the case, makes an excellent suggestion. Then Mr. Charlesworth, obviously also a very accomplished woodworker, approaches the topic from almost the direct opposite position. So much depends on the environment we work in and the tools, particularly any machines, we may use. I happen to have a small lunchbox planner, I will admit, so maybe I am in the middle somewhere. I am glad I have a Stanley #5 with a large radius in the blade for making the tapered legs for Windsor Chairs and Tables.... If I had a jointer (machine), but I don't and do not want one.

    I use green wood tools on white oak a good amount. When that oak dries though I may swap over to hand planes, particularly ones with radiused blades. I am now thinking that I might leave a #5 type plane with less/no radius for working tougher drier wood. Although I have a Veritas BUS smoother so I have a good heavy smoother for tough grain. So much depends on the specific work at hand.

  14. #14
    One of the best discussions of handtool understanding and with few posters and few words. Too often one "side" takes over and a different position is crushed when actually there are numerous positions that could be discussed and expanded. So much great understanding available here when it flows. Thank you.

  15. #15
    Join Date
    Feb 2014
    Location
    Lake Gaston, Henrico, NC
    Posts
    9,029
    You could camber the Cosman iron just enough to use as a smoother, and put a Jack camber on the stock iron. The wider mouth won't hurt you a bit with the big cambered iron, and you might not even have to move the frog. I'm not sure if this would work, but might be worth a try. The reason I have so many planes is that I don't like having to spend time switching things around. Once I have one set for one purpose, all I want to do is sharpen the iron when it needs it.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •