Prop Hardening

[John Beardslee]

Charcoal Grille

You will never get an in house stove hot enough to cause a problem, your grill is a possibility but hard control.

 

[John Beardslee]

Jimmy Allen’s account, ABC uses #275 alloy. It is annealed at 1,300F with an 11 second oil quench. The peop should be de-stressed at 340F for 20 minutes at this point. Then soak at 594-640F for 40 minutes to 1.5 hrs depending on prop size, then air cooled.
Thanks John

 

[Terry Keeley]

275 isn't coming up anywhere, got a link?

 

[John Beardslee]

275 isn't coming up anywhere, got a link?

Unfortunately no T, all I have is what Jimmy sent me. I’ll see if Jim will tell me what he is using. I’ve heard that he sometimes uses a mix of recycled alloy, so we might be chasing it for awhile.
Thanks John

 

[John Beardslee]

Unfortunately no T, all I have is what Jimmy sent me. I’ll see if Jim will tell me what he is using. I’ve heard that he sometimes uses a mix of recycled alloy, so we might be chasing it for awhile.
Thanks John

Terry, if you search 275 BeCu it should take you to a current sight with info. Let me know if you can’t get it and I will copy and forward.
Thanks John

 

[dwilfong]

http://www.matweb.com/search/datasheettext.aspx?matguid=079415ebbb3549cd8eab443386b404e8https://materion.com/-/media/files/...fs---heat-treating-copper-beryllium-parts.pdf

 

[Terry Keeley]

Terry, if you search 275 BeCu it should take you to a current sight with info. Let me know if you can’t get it and I will copy and forward.
Thanks John

Ha. I tried C275 but it didn't come up, 275C (C82800) sure does tho.

That material is very similar to Octura's 20C (C82500) and would take the same heat treat but I doubt that's what Jim is using. His props that I've seen don't look anything like Octura, more bronze colored than copper based.

Go ahead and ask jim what he's using if you don't mind, tell him Inquiring minds need to know!

 

[mtruex]

Jim is always available to answer questions. Just ask.

 

[John Beardslee]

Jim is always available to answer questions. Just ask.

I know, I always feel guilty, our conversations are never short and he’s try to get product out of the door but always shares his time. So I called, no hello just no I won’t tell you my material! So he follows IW, I said I don’t want to know your material but will you tell me how to heat treat it. He sure did, the process I outlined from Jimmy Allen is close enough that it should work fine. Don’t short cut the process and expect good results. Thank you Jim! Always a pleasure to talk with you!
Thanks John

 

[Buckshot]

So is annealing required prior to hardening?

 

[John Beardslee]

So is annealing required prior to hardening?

No

 

[John Beardslee]

No

No, but I wouldn’t skip the stress relieving

 

[Buckshot]

No, but I wouldn’t skip the stress relieving

Didn’t think so but had to ask.

 

[BACKEMF]

Tom Prezenka once told me that Octura props are 20C (C82500) so for that you first heat through at 1450F (20 mins or so) and water quench, it's then dead soft and perfect for finishing/bending etc.

Next you harden at 625F for about 3 hrs and slow cool. Don't try bending on it after that, lol. Holds a great edge too.

https://materion.com/-/media/files/...fs---heat-treating-copper-beryllium-parts.pdf
Without a kiln you can heat evenly to a dull orange with a torch (do it in the dark) , then stick it in the kitchen oven and run the cleaning cycle. Wala, hardened props and happy wife.

I've tried to find out what alloy Jim at ABC uses but haven't had much luck, seems it's a secret or something.

Thanks Terry. Has this been updated recently for ABC props?? I'm still searching.

Ray S

 

[BACKEMF]

Found my notes on hardening. These are the old equations from years back:
ABC props: Harden at 600* for one hour and let air cool
Octura props: Harden at 625* for 3 hours and let cool in oven
Now I am running mostly the new ABC's and found this to be about the best. It is not brittle and will allow some repitching if moderate.
575* for one hour. Let air cool.
If you need to anneal a prop after hardening, Octura's run at 1250* and Octura's at 1450* for an hour. Quench in oil, not water. Water boils away.
Stu

Stu, is this the final word on ABC props? Thanks in advance!

I take they don't need to be brought up to 1450'ISH* F first???

 

[Terry Keeley]

Thanks Terry. Has this been updated recently for ABC props?? I'm still searching.

Ray S

Brian Buass just told me something very similar to John's post #22:

1300F, quench (I've always used water on Octura props).

425F for 1.5 hrs, let slow cool.

I think the higher the second temp the higher the tensile strength but they can be brittle, I've thrown a blade or two over the years. A lower temp might still be "hard" but have some give.

 

[Alan Elzer]

A butane torch works for me to heat till a bright orange then quench in water. Clean it up blend as you please s/b, then heat to 550 for 5 or 6 hrs slow cool. You tube has lots of video's on how to build a cheap oven with probes & digital temp readouts for reasonable expenses.
ABC props have a lot more burelium than octura so heat treating is different. Jim is a great guy and will gladly talk with you about it.

 

[Tom Foley]

Anyone care to share how you are hardening your props?

On a cookie sheet , oven wide open 600+ degrees for several hours , remove and air cool . Not sure how hard they are but they don't deform after that and stay sharp . Like Terry said lol .

 

[Derret]

BITD (back in the day) I recall Don Pin. (sp?) had a simple HT method that he claimed to use:
use a clothes iron as a heat source - what setting?
put prop on iron covered up with a small tin can & heat up to max setting for a couple hours ?
What temp? ( this before heat guns & the invention of dirt!)
I don't have more info on this ... I used that method at times & never did lose a prop...
Tom P. used to have alot to say about guys 'heat treating' his products..
(Any oldsters from BITD recall this ? - back when just looking at nitro it would detonate! geeez...)
I did buy a lab type heat treat oven for proper HT eventually (to heat treat the steel races for roller bearing rods), and didn't see any
difference in HT methods for props...
Is a really hard prop what is needed?
All you EXPERTS can chime in here....

Dave Richardson
RPM Inc. (ret)

 

[Tom Foley]

BITD (back in the day) I recall Don Pin. (sp?) had a simple HT method that he claimed to use:
use a clothes iron as a heat source - what setting?
put prop on iron covered up with a small tin can & heat up to max setting for a couple hours ?
What temp? ( this before heat guns & the invention of dirt!)
I don't have more info on this ... I used that method at times & never did lose a prop...
Tom P. used to have alot to say about guys 'heat treating' his products..
(Any oldsters from BITD recall this ? - back when just looking at nitro it would detonate! geeez...)
I did buy a lab type heat treat oven for proper HT eventually (to heat treat the steel races for roller bearing rods), and didn't see any
difference in HT methods for props...
Is a really hard prop what is needed?
All you EXPERTS can chime in here....

Dave Richardson
RPM Inc. (ret)

Props can and will lose pitch and actually visibly "fold back " a little after they are worked and thinned especially heavy pitched back cut props . When that heavy twin is coming in and out of the water wide open there are some strong forces at work . The heat treating , even if not the most scientific method desrcibed , does strengthen the prop . However as mentioned they will crack if not annealed again . before bending .