Prop hardening questions

[Glenn Gates]

The BS is really free flowing now.

 

[dwilfong]

When I quenched I use 2 gallons of distilled water and with props being so small there was never an eruption. When quenching oil hardening tool steel/drill rod we used oil over water, ie: in a 5 gallon pail (steel) with water about 3/4 full and then enough 10 to 30 weight oil on top to have about 1 inch of oil over the water. When quenching steel we would swirl the object in a figure 8 pattern in the oil to balance the cooling to keep the object from warping.

Thanks, John

Cat urine...

Norm, how do you get the urine? :huh:

 

[Matt Mordja]

Good topic Doug,

Per B.W., Terry is spot on, kind of only going half way without the 1450'f

"When peak aging copper beryllium castings and weldments, the customer must always solution anneal prior to age hardening. However, if peak properties are not required, castings can be age hardened from the as cast condition without the solution anneal."

 

[Michael Caruso]

Good topic Doug,

Per B.W., Terry is spot on, kind of only going half way without the 1450'f

"When peak aging copper beryllium castings and weldments, the customer must always solution anneal prior to age hardening. However, if peak properties are not required, castings can be age hardened from the as cast condition without the solution anneal."

Blacksmiths in the old days quenched in urine and looking at colors of metals to tell temps is a lost art. That dull red in a dark room tells a lot whether or not its stuffing box tubing or props. I am told (lol) be careful after turning on the lights as to which end of the stuffing box tube up pickup. Ha

 

[Norm Doerr]

When I quenched I use 2 gallons of distilled water and with props being so small there was never an eruption. When quenching oil hardening tool steel/drill rod we used oil over water, ie: in a 5 gallon pail (steel) with water about 3/4 full and then enough 10 to 30 weight oil on top to have about 1 inch of oil over the water. When quenching steel we would swirl the object in a figure 8 pattern in the oil to balance the cooling to keep the object from warping.

Thanks, John

Cat urine...

Norm, how do you get the urine? :huh:

You need to get some cats... trap some strays, probably need at least three large felines or more....Depends on how much heat treating you want to do.

Then get some of these http://www.shopmedvet.com/product/tom-cat-catheter-kendall-3-5-french-5-5inch-open-end/catheters-suction-supplies

 

[John Beardslee]

Good topic Doug,

Per B.W., Terry is spot on, kind of only going half way without the 1450'f

"When peak aging copper beryllium castings and weldments, the customer must always solution anneal prior to age hardening. However, if peak properties are not required, castings can be age hardened from the as cast condition without the solution anneal."

Hi Matt,

I've heard that the new ABC props are of a different BeCu alloy and do require a higher temp for annealing and heat treating but the 2% alloy thay Octura props were cast from only required 1100F. I've not talked to anyone at BW in years so with newer technology and equipment for analysis that is available today may have changed the temp for the annealing process.

Thanks, John

 

[John Beardslee]

Good topic Doug,

Per B.W., Terry is spot on, kind of only going half way without the 1450'f

"When peak aging copper beryllium castings and weldments, the customer must always solution anneal prior to age hardening. However, if peak properties are not required, castings can be age hardened from the as cast condition without the solution anneal."

Blacksmiths in the old days quenched in urine and looking at colors of metals to tell temps is a lost art. That dull red in a dark room tells a lot whether or not its stuffing box tubing or props. I am told (lol) be careful after turning on the lights as to which end of the stuffing box tube up pickup. Ha

Hi Mike,

A guy I used to work with was a friend of Randall of Randall knives. Randall collected the urine from the urinals in his machine shop to use to quench his custom knives. Randall did a minature Bowie knife and Arkansas toothpick that went to the moon during the Apollo missions. I can't imagine how it must smell when he would quench hot metal in that stuff.

Thanks, John

 

[John Beardslee]

One thing I think would be useful for heat racing props would be to develop a recipe for heat treating BeCu to less than full hard ie: 1/2 or 3/4 hard or ? This may allow slight tweaking or bending without cracking or breaking the blades.

Thanks, John

 

[Michael Caruso]

One thing I think would be useful for heat racing props would be to develop a recipe for heat treating BeCu to less than full hard ie: 1/2 or 3/4 hard or ? This may allow slight tweaking or bending without cracking or breaking the blades.

Thanks, John

2nd that John I would be fine with typing it up for everyone. Great information to all of us must not be lost.

 

[dwilfong]

I have done many props and thy still break if you V cut them.

Now the one Norm did is still in one piece after a few years of testing.

So what gives Norm?

Is it the cat pis?

 

[Norm Doerr]

I have done many props and thy still break if you V cut them.

Now the one Norm did is still in one piece after a few years of testing.

So what gives Norm?

Is it the cat pis?

Secret Thing is that a lot of it is trial and error... Even though many props are supposed to be made of a published or said alloy, I am almost sure they do not have a testing lab to measure production samples to make sure they are all exact. You also have other factors involving the oven, ramp times, soak times, quenching procedures.

Your best bet is to do what Beardslee is saying and you should be okay.

Actually Cow Pee can be bought.. (tarnex) that works just as good.

 

[Mike Larson]

I've a small jewelry kiln... and the instruction I recieved from the guy I got it from has 750 degrees one hour and 350 for 3.... I've not tried the thing yet, as it takes a dedicated 20 amp circuit easily...( pops a standard 15 breaker) I'd had a half dozen propellors my mentor had done and they were hardened to the point you are done sharpening and forget touching up... as research and testing is always ongoing, finding "the one".. seems constant, ie: locking the cup and pitch in would be great..... I work them as cast, per pitch rake and cup... hardening would be great per keeping the edge on them, as even as cast they dull quickly, and roll edges easily from debris strikes and whatnot..... whats what with these temperatures vs the other stated major temps, and quenching?,.. I'm in my garage of course, and quenching in oil reeks, and I'm understanding the basic fact heating any metal produces oxide, or similar airborne chemical, just how dangerous is this, could it be?.. I already get trussed up to just work them, respirator, suit and gloves,( should mechanical machinery be used) but intensively does the heating process really release the crap at even worse levels?... I'm in constant thought on throwing blades, and danger combined with even working them in the first place... but soft, thinned propellors suck.... instruction and recommendations would be welcome... like... send 'em to Norm, easily enough, ...aint worth my pain.... thanks Mike

 

[dwilfong]

There is no smell to speak of quenching in oil. You barely get a woof of smoke sticking the prop in it.

The small oven I use plugs in to any 110v circuit.

Can't smell a thing using the little oven.

Now you get a 220v kiln and spend hours heating it up Ya you might smell some of the old crap that may be in a old unit.

You will also need a special dedicated circuit and a place to put it in the garage.

I just put mine on the wood work bench with a piece of tile under it.

No need for over kill it's just a toy boat prop.

The major advantage in doing your own is you can change it real easy when testing.

Just anneal and work the prop then re-harden.

When you get what you like then send it to Norm. It will be set in stone.

 

[DPeterson]

One thing I think would be useful for heat racing props would be to develop a recipe for heat treating BeCu to less than full hard ie: 1/2 or 3/4 hard or ? This may allow slight tweaking or bending without cracking or breaking the blades.

This is exactly what my intentions were. I don't want my props over-aged and brittle. Just hard enough to help hold pitch.

So to go this direction I take it the annealing is still neccessary? What would be your gut approach to this?

Good info here. John - I will be calling you up when I more of my set up together.

Doug

 

[Michael Caruso]

One thing I think would be useful for heat racing props would be to develop a recipe for heat treating BeCu to less than full hard ie: 1/2 or 3/4 hard or ? This may allow slight tweaking or bending without cracking or breaking the blades.

This is exactly what my intentions were. I don't want my props over-aged and brittle. Just hard enough to help hold pitch.

So to go this direction I take it the annealing is still neccessary? What would be your gut approach to this?

Good info here. John - I will be calling you up when I more of my set up together.

Doug

45 years ago and old guy told me if I want to anneal very small parts like out props to use boring bar chips. I used the boring bar chips to anneal good grade Blue Point hardened Allen set screws so I could drill them with a .018-.020" drill bit. Great way back in the day to modify racing engine oil systems so the rod and main bearings would live. Automotive machine shops that bore cylinder blocks oversize will have plenty for every one in boating for free. All you would have to do is ask them for some. LOL I forgot all about using it for years until this prop heat treating came up and it does a great job. I will get some from one of my friends this week and try it on a hurt M-645 will report. These chips are real small as most cast iron cylinders get bored approx .024" oversize total diameter. So the chips can be half size .012" or .006". I think it will do a better job than steel shot as far as even cooling unless the steel shot is very small as the boring bar chips.

Just thinking it might not Shock the prop material as quick but more evenly. Dunno?

John B. Saved me from screwing up........I do screw up every now and then. Thanks again John 10:36 AM 10.13.13

Hi Mike,

I sounds like you may be getting the annealing process for ferrous metals confused with the process for non-ferrous metals. Ferrous metals (iron based) require a slow cooling from high temps to anneal and non-ferrous metals require a fast cooling from high temps to anneal.

Thanks, John

 

[Terry Keeley]

https://www.intlwaters.com/gallery/albums/userpics/10068/Prop%20Heat%20Treat.pdf

 

[J Solinger]

Even though it's not the very best, going straight to the hardening stage without the annealing stage will improve your props shape holding ability and make them less prone to edge dings. I don't recomend annealing finished props though. That process is pretty severe and would distort them so I would skip it. As has been said, for best material performance 1rst anneal, 2nd do your prop work, 3rd harden. And skip the piss, use salt water for annealing. LOL

As for 1/2 hard or 3/4, octura props are likely about 1/2 hard as cast. Try to find some data on tensil strength and elongation as it relates to hardness in this material.

 

[Michael Caruso]

Even though it's not the very best, going straight to the hardening stage without the annealing stage will improve your props shape holding ability and make them less prone to edge dings. I don't recomend annealing finished props though. That process is pretty severe and would distort them so I would skip it. As has been said, for best material performance 1rst anneal, 2nd do your prop work, 3rd harden. And skip the piss, use salt water for annealing. LOL

As for 1/2 hard or 3/4, octura props are likely about 1/2 hard as cast. Try to find some data on tensil strength and elongation as it relates to hardness in this material.

Thanks Joe,

I was going to ask about salt water.

Trudie @ Octura who has made more Octura parts with her own hands than anyone would believe is a wealth of information just call her. She can tell you the exact propeller material. CST 1-847-674-7351 best times 10:00-2:00 or leave a voice mail or you could fax over your questions 1-847-674-7363 any time day or night.

 

[Terry Keeley]

Octura's alloy is 20C, also from page 4 of my above post:

"Because most salts will attack copper beryllium at

temperatures in the solution annealing range, solution
annealing should not be performed in a salt bath."

 

[John Beardslee]

One thing I think would be useful for heat racing props would be to develop a recipe for heat treating BeCu to less than full hard ie: 1/2 or 3/4 hard or ? This may allow slight tweaking or bending without cracking or breaking the blades.

This is exactly what my intentions were. I don't want my props over-aged and brittle. Just hard enough to help hold pitch.

So to go this direction I take it the annealing is still neccessary? What would be your gut approach to this?

Good info here. John - I will be calling you up when I more of my set up together.

Doug

45 years ago and old guy told me if I want to anneal very small parts like out props to use boring bar chips. I used the boring bar chips to anneal good grade Blue Point hardened Allen set screws so I could drill them with a .018-.020" drill bit. Great way back in the day to modify racing engine oil systems so the rod and main bearings would live. Automotive machine shops that bore cylinder blocks oversize will have plenty for every one in boating for free. All you would have to do is ask them for some. LOL I forgot all about using it for years until this prop heat treating came up and it does a great job. I will get some from one of my friends this week and try it on a hurt M-645 will report. These chips are real small as most cast iron cylinders get bored approx .024" oversize total diameter. So the chips can be half size .012" or .006". I think it will do a better job than steel shot as far as even cooling unless the steel shot is very small as the boring bar chips.

Just thinking it might not Shock the prop material as quick but more evenly. Dunno?

Hi Mike,

I sounds like you may be getting the annealing process for ferrous metals confused with the process for non-ferrous metals. Ferrous metals (iron based) require a slow cooling from high temps to anneal and non-ferrous metals require a fast cooling from high temps to anneal.

Thanks, John