• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.
[4]

Boring Head Arbor: 1018 Or 4140 Or Other?

January Project of the Month [3]
[10] Like what you see?
Click here to donate to this forum and upgrade your account!

Uglydog

Active User
H-M Supporter-Premium Member
Joined
Dec 6, 2012
Messages
2,240
Likes
1,260
#1
I've had a Criterion DBL204 without an arbor.
I've got a project where I'll need the reach and rigidity of the 204 so I thought I'd finally get the arbor made.
Am planning on a 1inch arbor and the requisite 1.5"x18 threads.

I've got 2inch 4140 and 1018 on the shelf.
I'm thinking I should make her out of 4140 about .999 and heat/quench and temper.
Any strong recommendations for an alternative?

Thoughts?
Concerns?
Recommendations?

Thank you for any/all suggestions.
Daryl
MN
 

Bob Korves

H-M Supporter - Sustaining Member
H-M Supporter - Sustaining Member
Joined
Jul 2, 2014
Messages
4,502
Likes
4,782
#2
Hi Daryl,
It might warp a bit when you heat treat it, so it might be worth leaving extra stock for grinding it to size after hardening and tempering. Actually, a boring head arbor does not need extreme radial accuracy, or hardness for that matter. A 1" shank of unhardened 4140 should support the boring head through everything but a major crash, only real downside would be more wear on the 1" shaft.
 

george wilson

Global Moderator
Staff member
H-M Supporter-Premium Member
Joined
Jul 26, 2011
Messages
3,487
Likes
758
#3
I agree with Bob about the 4140. I never harden R8 shanks that I make. I keep a few old truck axles around for making good,strong arbors and shanks. Axles are hardened only where they run as bearings or through bearings. The rest is readibly machinable. But definitely superior to mild steel.
 

rgray

Active User
H-M Supporter-Premium Member
Joined
Nov 26, 2012
Messages
840
Likes
389
#4
That's a big arbor and probably is just fine raw. But...nothing like a hardened tool, so if you have the ability I would heat treat and temper just so it looked cool.
Grinding after heat treat as Bob said would be great to if that is an option.
 

Uglydog

Active User
H-M Supporter-Premium Member
Joined
Dec 6, 2012
Messages
2,240
Likes
1,260
#5
All,
Thanks for the feedback!
My oven would easily do it, but I don't have a grinder.
I've got a couple grinders available to borrow, but no cylindricals.

I'll run with the raw 4140.

Daryl
MN
 

george wilson

Global Moderator
Staff member
H-M Supporter-Premium Member
Joined
Jul 26, 2011
Messages
3,487
Likes
758
#6
i have everything necessary to heat treat and grind tool steel arbors. but,i don't bother with large ones as it just isn't necessary.

typed with one hand while eating a sandwich. hence no caps.
 

scwhite

Active Member
Active Member
Joined
Mar 19, 2017
Messages
313
Likes
237
#8
I've had a Criterion DBL204 without an arbor.
I've got a project where I'll need the reach and rigidity of the 204 so I thought I'd finally get the arbor made.
Am planning on a 1inch arbor and the requisite 1.5"x18 threads.

I've got 2inch 4140 and 1018 on the shelf.
I'm thinking I should make her out of 4140 about .999 and heat/quench and temper.
Any strong recommendations for an alternative?

Thoughts?
Concerns?
Recommendations?

Thank you for any/all suggestions.
Daryl
MN
4140
 
[6]
[5] [7]