Looking at making my own bowl scrapers

[Andrew Derhammer]

I want to make a scraper for a bowl. I was just going to order steel bar from mcmaster carr to make it. How thick should the steel be?

[Bernie Weishapl]

Mine is a 1 1/8" wide and 3/8" thick. I wanted a good heavy one.

[Andrew Derhammer]

Mine is a 1 1/8" wide and 3/8" thick. I wanted a good heavy one.
Thanks. I figured that i could just grind my own and make my own tool handle and save some $. I'm looking at McMaster Carr now. A piece of O1 tool steel 1 1/2" wide by 1/2" thick by 18" long is $34

[Bruce Pennell]

Andrew I just picked up a truck spring the other day from my buddies truck repair yard, he also gave me about 20 valves out of a motor. The valves I cut the tops off and they make great rounded over scrapers. Fit right into my Don Pencil large boring bars. Was going to make a couple handles but don't need to now. Its been to hot out to cut the spring, might do it early in the morning this week sometime. I'm making two heavy scrapers, one inboard one out board. I got to try similar ones when I got my lesson from Wally Dickerman. I'm very impressed with the valves, they are very hard and made to take a lot of heat (duralite) I believe is what my friend called the metal. The ones made to take the newer fuels. I made one round nose. like you would make out of square HSS, and a square scraper tool. They cut as well as my HSS bars. I'll let you know how the spring works out, spring steel should make a good scraper. Now I just have to break out the plasma cutter and cut a couple blanks, and grind an edge. Total cost...my time and a lot of fun screwing around.

[Andrew Derhammer]

Andrew I just picked up a truck spring the other day from my buddies truck repair yard, he also gave me about 20 valves out of a motor. The valves I cut the tops off and they make great rounded over scrapers. Fit right into my Don Pencil large boring bars. Was going to make a couple handles but don't need to now. Its been to hot out to cut the spring, might do it early in the morning this week sometime. I'm making two heavy scrapers, one inboard one out board. I got to try similar ones when I got my lesson from Wally Dickerman. I'm very impressed with the valves, they are very hard and made to take a lot of heat (duralite) I believe is what my friend called the metal. The ones made to take the newer fuels. I made one round nose. like you would make out of square HSS, and a square scraper tool. They cut as well as my HSS bars. I'll let you know how the spring works out, spring steel should make a good scraper. Now I just have to break out the plasma cutter and cut a couple blanks, and grind an edge. Total cost...my time and a lot of fun screwing around. I just picked up A1 tool steel 3/8" thick 1 1/4" thick and 18" long for $28. I'm only using a mini lathe right now so i don't need something huge. Although i am saving pennies for a nova 1624-44.:D

[Bruce Pennell]

Andrew let us know how making your scraper worked out. Good luck with the new lathe, I'm loving my PM, best money I every spent. Sean at Toolnut gave me a great deal. Good Luck ...Bruce

[Gordon Seto]

Andrew,

You have to check whether the A1 and O1 steel you are getting are already hardened or in annealed state for ease of machining. If they are not hardened, they may need heat treating, quenching, and tempering. Otherwise they won't hold the edge. Heat treating a large piece of steel is more demanding then a small drill rod for DIY with a torch.

[Andrew Derhammer]

Andrew,

You have to check whether the A1 and O1 steel you are getting are already hardened or in annealed state for ease of machining. If they are not hardened, they may need heat treating, quenching, and tempering. Otherwise they won't hold the edge. Heat treating a large piece of steel is more demanding then a small drill rod for DIY with a torch.
It says air hardened. Besides with a scrape you should sharpen every 20 seconds. You cut with the burr not the edge.

[Gordon Seto]

Another alternative is getting some used up HSS planner blade and cut it into cutters and make your own shaft with regular steel like this one:
http://www.leevalley.com/wood/page.aspx?c=2&p=49135&cat=1,330,49233&ap=1

[Gordon Seto]

Not necessary with the burr, it depends on wood. Sometimes you can get a better finish with no burr at all. Even with HSS, the burr may not last 20 seconds.

Does file skate on the steel? Last time (couple years ago) I checked with ENCO, the longest hardened steel they carried was no more than 8" long. Do you have the item number?

[Gordon Seto]

It says air hardened. Besides with a scrape you should sharpen every 20 seconds. You cut with the burr not the edge.
The O1 is annealed

Part Number: 9516K172 (http://www.mcmaster.com/itm/find.ASP?tab=find&context=psrchDtlLink&fasttrack=False&searchstring=9516K172) $33.90 Each
Material
Multipurpose Oil-Hardened O1 Tool Steel
Finish/Coating
Ground
Shape
Sheets, Bars, and Strips
Sheets, Bars, and Strips Type
Plain
Thickness
1/2"
Thickness Tolerance
±.001"
Length
18"
Length Tolerance
+1/4"
Width
1-1/2"
Width Tolerance
+.005"
Tolerance
Precision-Ground
System of Measurement
Inch
Temper/Condition
Annealed
Hardness
Rockwell B85-B96
Maximum Attainable Hardness
Rockwell C60-C65
Yield Strength
50,000 to 60,000 psi
Specifications Met
American Society for Testing and Materials (ASTM)
ASTM Specification
ASTM A681
WARNING
Hardness and yield strength are not guaranteed and are intended only as a basis for comparison.

I can't find the A1, but there is a A2
Part Number: 9019K194 (http://www.mcmaster.com/itm/find.ASP?tab=find&context=psrchDtlLink&fasttrack=False&searchstring=9019K194) $27.38 Each
Material
Multipurpose Air-Hardened A2 Tool Steel
Finish/Coating
Ground
Shape
Sheets, Bars, and Strips
Sheets, Bars, and Strips Type
Plain
Thickness
3/8"
Thickness Tolerance
±.001"
Length
18"
Length Tolerance
+1/4"
Width
1-1/4"
Width Tolerance
+.005"
Tolerance
Precision-Ground
System of Measurement
Inch
Temper/Condition
Annealed
Hardness
Rockwell B89-B99
Maximum Attainable Hardness
Rockwell C58-C65
Yield Strength
51,000 to 108,000 psi
Specifications Met
American Society for Testing and Materials (ASTM), Military Specifications (MIL)
ASTM Specification
ASTM A681
MIL Specification
MIL-QQT-570A
WARNING
Hardness and yield strength are not guaranteed and are intended only as a basis for comparison.

If these are the two that you are talking about, they are both annealed.
They just have the chemical composition to be O1 and A2 tool steel, they are soft in current state. They need to be heat treated to have the hardness.

[Andrew Derhammer]

It was A2 and it's ordered. Guess i'll have to heat treat it.