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Thread: Powder metal scraper?

  1. #1
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    Powder metal scraper?

    I only have a limited number of tools for the lathe so far. Today I've decided I could use a round nose scraper. So far I've bought just Crown simply because the price and quality seams good. I have a Crown 1" bowl scraper that's curved but a diameter of about 1 1/2" or so. It's a little large to get into the corner of a bowl so I was thinking a 3/4" round nose would be useful. I'm on the edge about getting a negative edge scraper but think I want to wait until I have more experience with sharpening. One of the reasons I went with Crown is simply because I wanted to learn on good quality but not too expensive.

    I did look at Thompson but I don't have any ash (we are about to loose them due to the Emerald Ash borer so I've been letting them grow as big as possible before harvesting them) to make a handle out of. I might have some yellow birch but I haven't looked into if it would make a good wood for a handle. I can't see buying something that I can make. I wasn't able to tell from their website, do you have to specify what shape you want? They just list widths and the picture shows them without an edge but they say they come sharp.

    D-Way only sells negative rake scrapers. I think I would have no issues sharpening it but I would like to spend more time learning how to turn than wondering if it's my skill on the lathe or if I didn't get a good burr on the tool. Down the road seams like a better time to learn.

    Sorbey seams to be more expensive than the Crown but I don't know if it's any better. Crown makes a regular high speed steel, a cryo version for the same amount ($34 from Hartsville is almost throw away tool money) or powder metal for almost twice the price. I see Thompson only sells tools that are made with powder metal. I did a search in the turner's forum but the only thing I came up with was on gouges. What do people think, is it worth getting power metal for a scraper?

  2. #2
    Join Date
    Mar 2007
    Location
    Wetter Washington
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    888
    No, Dave (D-way) sells regular scrapers also. But his M42 steel is not powder.

    Personally I'm not certain that there is that big an advantage in using V10 vrs M42 for a scrapper.

    (note to sell, we really need to get a large NR scrapper from either Dave or Jimmy (boxmastertools))
    Making sawdust mostly, sometimes I get something else, but that is more by accident then design.

  3. #3
    Join Date
    Nov 2006
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    Erie, PA
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    564
    The Thompson scrapers generally come unsharpened but Doug will grind them at symposiums. You can call him and ask. The 10V steel stays sharper longer than other steels. You can use most any wood for handles, does not have to be ash. One noted turner uses tree branches for handles.

  4. #4
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    Feb 2018
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    Cookeville TN
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    338
    Ihope Reed Gray steps in on this. I don't think a particle metal tool holds a burr longer than HSS. It does hold an edge longer. Even if it does hold an burr longer we are talking about seconds and to me it's not worth paying the extra. To cut clean with a scraper you need a fresh good quality burr so it's important to play around and learn what works for you. I have several HSS scrapers and one gives an excellent burr straight off the grinder. The other 2 I have to roll the burr myself.

  5. #5
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    I prefer Thompson steel for scrapers. I buy them straight, square-ended and grind to suit me. I've also ground scrapers from other Thompson steel: skew chisels, detail gouges, and the round rod stock he sells. I think they hold an edge extremely well, as well as or better than any other scraper I have from HSS, and I have a bunch. (Note that I don't typically use the burr from grinding, but hone and strop the ground end and burnish a burr with a carbide rod.) I've even turned steel on the wood lathe with a scraper from Thompson steel, although it did need sharpening more often.

    For special-use scrapers I grab and grind something from a box of old tools I keep on hand for students or give-away.

    I see no reason to buy a negative rake scraper or ANY scraper with any particular shape when I can grind it to any shape I want. Admittedly, significantly reshaping a large scraper can be tedious - use the coarsest wheel in your shop. I bought an 80 grit CBN wheel from Rizza Woodturners Wonders just for reshaping tools. It works better and quicker than I even imagined.

    These are my favorites NRS I ground for bowls and platters, and a few of the small scrapers I use for small things such as boxes and such. (I've posted these photos before - I really need to take some better pictures.)

    scrapers_neg_rake.jpg scrapers_small_thompson.jpg

    You don't need ash for handles. I've made useful handles from oak, cherry, maple, bubinga, persimmon, sassafras, maple, osage orange, olive, hickory, and whatever else I had around. You could use basswood for a scraper handle unless you used it for aggressive hollowing like some do. I know it's a long walk, but if you get down this way stop in and we'll make all the handles you can stand - I have way too much handle-sized wood.

    In fact, I use most of my negative rake scrapers without no handles. Since there is no significant force on the tool when used as intended, I find no reason to make a handle. (The tools take up a lot less space this way!)

    I think of the price of a higher quality new tool this way: it is almost insignificant compared to the cost of the other things related to turning: lathes, chucks, grinders, bandsaw, jigs, books, the shop itself, taxes, electrical power for air conditioning - and time.

    JKJ


    Quote Originally Posted by Alex Zeller View Post
    I only have a limited number of tools for the lathe so far. Today I've decided I could use a round nose scraper. So far I've bought just Crown simply because the price and quality seams good. I have a Crown 1" bowl scraper that's curved but a diameter of about 1 1/2" or so. It's a little large to get into the corner of a bowl so I was thinking a 3/4" round nose would be useful. I'm on the edge about getting a negative edge scraper but think I want to wait until I have more experience with sharpening. One of the reasons I went with Crown is simply because I wanted to learn on good quality but not too expensive.

    I did look at Thompson but I don't have any ash (we are about to loose them due to the Emerald Ash borer so I've been letting them grow as big as possible before harvesting them) to make a handle out of. I might have some yellow birch but I haven't looked into if it would make a good wood for a handle. I can't see buying something that I can make. I wasn't able to tell from their website, do you have to specify what shape you want? They just list widths and the picture shows them without an edge but they say they come sharp.

    D-Way only sells negative rake scrapers. I think I would have no issues sharpening it but I would like to spend more time learning how to turn than wondering if it's my skill on the lathe or if I didn't get a good burr on the tool. Down the road seams like a better time to learn.

    Sorbey seams to be more expensive than the Crown but I don't know if it's any better. Crown makes a regular high speed steel, a cryo version for the same amount ($34 from Hartsville is almost throw away tool money) or powder metal for almost twice the price. I see Thompson only sells tools that are made with powder metal. I did a search in the turner's forum but the only thing I came up with was on gouges. What do people think, is it worth getting power metal for a scraper?

  6. #6
    I put up a video a short while back called 'Scary Scrapers' which covers shapes and scraper use on bowls. You can find it here or on You Tube. I prefer a quarter round nose profile, or if you only have one, then a round nose. As near as I can tell, there is no difference in performance of the Thompson tools and the D Way for edge holding or sharpness. I prefer the Big Ugly tool for heavy roughing and other scrapers for shear scraping (covered in that video as well. I do not consider a scraper a good tool for fine finish cuts on bowls using a flat on the tool rest cut, but they are excellent for shear scraping with a burnished burr (covered in another video).

    robo hippy

  7. #7
    Join Date
    Apr 2018
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    Cambridge Vermont
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    As my skills grow I'm sure that it'll open up more options. I wish I could say that I never made a mistake and didn't have to worry about catching an edge with a scraper but that's not the case yet. I wouldn't feel comfortable not having a handle. In fact that's why I wanted to stick with ash. My long term goal is to find the 4 or 5 tools that are my go to tools and replace them with nicer, more expensive tools. Burnishing to form the burr is also something I plan on switching to. But right now there's too many variables until I get more time on the lathe.

    So far I've only made two bowls from a cherry tree that snapped in a wind storm last fall so it has stress damage. The first bowl split apart a couple days after turning (I was hoping it would just warp). The second seams to be fairing much better. Doing bowls means dealing with two spots of end grain both inside and outside of the bowl. Spindles probably would be easier to start on but I have lots of bowl blanks to play with. I'm thinking cherry is a softer wood so it should be good to practice on.

  8. #8
    Join Date
    May 2009
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    Boston
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    Hurricane tools has a new line of tools using the M42 cryo steel which are reasonably priced. I picked up the 1 inch square and round nosed scraper and the work well and hold an edge nicely.

    I bought them so I could turn one into a half round scraper.
    Don

  9. #9
    Lots of good advice here. I have found this to be useful as well when trying to understand the potential advantages of powdered metal: http://www.cindydrozda.com/html/ToolSteel.html

  10. #10
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    Sep 2015
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    Don Jarvie, I read your post about Hurricane M42 Cryo tools. I did a google search and could only come up with M2 cryo tools. I'm wondering if you meant M2 or I am just having trouble finding the M42. IMHO, an M2 tool is not that much different from HSS to justify much of a premium cost. Let me know if it is indeed M42.

  11. #11
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    Quote Originally Posted by Brice Rogers View Post
    Don Jarvie, I read your post about Hurricane M42 Cryo tools. I did a google search and could only come up with M2 cryo tools. I'm wondering if you meant M2 or I am just having trouble finding the M42. IMHO, an M2 tool is not that much different from HSS to justify much of a premium cost. Let me know if it is indeed M42.
    This page has an invitation to call a metallurgist to answer questions about steel, at least theirs:
    https://carterandsontoolworks.com/bl...-the-science-1

    Also, here is something about cyro hardening of M42. I didn't read it. mit.imt.si/Revija/izvodi/mit156/kivak.pdf
    I noticed it with a google search of cryo hardened M42 HSS.

    BTW, you said "IMHO, an M2 tool is not that much different from HSS to..."
    I thought M2 is HSS, one of the many types.

    JKJ

  12. #12
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    Oct 2008
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    Kapolei Hawaii
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    I like my Crown Pro PM tools....... IF I had to choose only 1 gouge, it would be my Ellsworth 5/8" Pro PM gouge. Yes I have many other brands, but that is my favorite. Just my $0.02.
    I also thought M2 is HSS..... For your original question, I think it's worth getting PM vs HSS for a scraper. Or any tool. Not including M42, which supposed to be awesome. My grunt work gouge is an M42. So sharpening is kept to a minimum.

  13. #13
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    My apologies they are M2 cryo. My go to tools are the Crown PM but these are reasonable to learn or experiment with.
    Don

  14. #14
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    Apr 2018
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    Cambridge Vermont
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    When I looked at the Hurricane tools one site said they bought the metal from Crown and put their own handles on them.

  15. I favor Thompson Tools.

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