Collins rafting on crack (relapsed and OD'd)

If you use a pit forge you will need to get more air to the fire to get it hot enough. A couple of feet of iron pipe with a blow drier to the bottom of the pit could work. The head needs to get a couple of shades past non magnetic. If you use oil, be careful of the flare up. If you can get 3 or 4 gallons of used canola oil that would be great. Good luck and test the hardness with a file after the quench and before the temper.
 
I decided to fire it in charcoal, a whole 18lb bag.




While I was picking up some used motoroil from my brother-in-law he informed me that charcoal was not going to be hot enough unless I had a bellows to inject some oxygen into the fire. I hadn't thought of that. He recommended going back to our metal artist friend and letting him go at it with his torch.

I ignored his advice and went with charcoal anyway, but first I needed to figure out this whole bellows thing. I thought of using my air compressor and an air nozzle as a bellows but decided that the thin stream of air would be moving too fast and might blow coals out of the fire. I figured a shop vac in reverse would be the way to go. Mine has an attachment with a wide flat nozzle approximately half inch by 3 inches. Here is my set up with the metal bucket of oil at the ready and the fire freshly started.




I also used the fireplace tongs, poker and shovel. One of those magnets attached to a telescoping pointer type metal rod that would typically be used to retrieved nuts or bolts dropped into difficult to reach places in an engine compartment was used to test for magnetism. I didn't really want to get my flesh too close to that red hot chunk of steel to test it for magnetism.

I got the fire going good and hot. Note, if you are contemplating using this open fire shop vac bellows method you really need room for the sparks to fly. Here I am bringing the poll up to temp.




I opted for the two separate heatings method and heated the poll up until it was no longer magnetic. Here it is just before quenching. I have no idea how many shades past non-magnetic it was. This was done when it was dark outside tonight and the picture makes it look a bit more yellow than I thought it looked to the naked eye. All I know is it was freakin' hot and I was super excited that the magnet was no longer attracted to it so I quenched it.




Next, I heated the bit.




My wife was upset she missed the quenching of the poll so she came out and got some action photos for me. This is me and my bellows getting the bit up to temp.




Its ready for the quenching.




This part gets pretty intense when using oil.




It makes for some nice photo ops.






I have yet to clean the axe head up but this is what it looked like after 2 firings and quenchings.



It should be cool enough now to test the treatment with a file and then temper it.

Thanks Pegs and Bo T for the advice. I doubt I would have taken on this project without your input. I also must thank my lovely wife for letting me do this kinda shit in the front yard.
 
I love it. Front yard heat treatment without special equipment.
That axe will obviously be a keeper with a strong personal bond.
 
wow! way to go! Looking forward to the final results. And kudos to your wife - the front yard no less.
 
Awesome!

Next you need to polish it at least enough to expose bare metal. Then heat treat it in your oven. Try an hour at 475° or 500°. Then check it both by the temper color that shows on the bare metal and with a file. If it's still too hard to file then give it another hour 25° hotter.

Here's a color temper chart, appropriately from 'The Backyard Blacksmith' by Lorelei Sims. Great book - highly recommended. You're looking for purple.

Temper%20colors%20BkYd%20BlkSmt.jpg


Remember, your oven's thermostat won't be exact and your temper color will likely show hotter than the setting you used on your oven.
 
My masting axe became filable after the 3rd hour. First hour was at 450°. Then cooled and file tested. Next hour at 475° and tested again. 3rd hour at 500° did it for me. Of course we have different steel, quenched at different temperature and tempered in different ovens. So the file is really your best indicator.

Temper%20color2.jpg
 
The hardening temperature is usually about 75F above the non-magnetic temp !
Motor oil has toxins in it --Stick to canola oil or other veggie oil .
The only axe head I've found in the woods was in surprizing ly good shape .I sure saved myself lots of work !!
 
Bo T said:
It looks like you got it hot enough:) Did you try a file test?
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Yes, I tried to file it and it was quite easy to file. I have a feeling that it was not hot enough.

I put it in the oven to temper anyway and its now just started cooling. We will see what it looks like in the morning. I guess I will most likely be heat treating it again, which was fun so I don't mind doing it again.

BTW, I would love to be using canola oil to quench it but I don't have a substantial amount of used canola laying around. If I start heat treating more items I will switch to something less toxic but for now since I have the stuff, motor oil it is.

edit: I did a little research and now believe that the problem was with my quench. I think my technique was a little off and that is why it didn't harden properly.
 
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I have come to the conclusion that I definitely need to fire it again.

This morning I awoke excited to see what color it turned in the oven last night. I was encouraged that the bit was blue at the edge fading through purple to dark brown. Maybe it needs to be just a tad hotter for proper temper?




So, I touched it with my new Simonds mill bd file that has only been used to work one double bit. The Simonds cut fairly easily so I dug out a couple of my Nicholson bastards that I am more familiar with and they were having a harder time cutting it so I was starting to think it was ok and wouldn't need a new heat treatment. Then I decided it would be a good idea to compare it to the no name double bit using all the files. The double bit is much harder! Its back to the fire for the Collins crack head for more treatment.

I think what may have happened last night was that during the quench I didn't move it up and down enough. Apparently, leaving it stationary during the quench can create oil vapor that acts as a barrier around the tool impeding the heat transfer resulting in slower cooling of the tool. Moving the tool up and down slightly facilitates more oil contact and quicker heat dissipation. Luckily I didn't stir it in a circular motion either, so that is good. Stirring it during the quench can warp the tool and we all know that a warped tool is no good. Also, I may have pulled out too early (yeah, I worded that just for you folks with dirty minds). Anyway, I left it in the oil for about 15 seconds or so on each quench but the oil was by no means done bubbling when I lifted it out. I then put it back in to cool down more. This next round of heat treatment I will be patient and leave it in until the oil stops bubbling and move it gently up and down the whole time. Any thoughts on this would be much appreciated.

Until next time, which will be after I change out a ball joint on my truck today, have a good one and thanks for looking.
 
Judging by your earlier photo I'm sure you had plenty of heat for the quench. Make the corrections to your quenching process and I bet you'll be fine.

Also, if you weren't actively cooling the pole while heating the bit then you would have likely tempered the pole. If you polish a line of steel leading to the pole before heating the bit then you can watch to see if the color starts running to the pole and interrupt it with a few shots from a spray bottle. Or as a precaution just spray the pole occasionally during the heating of the bit without watching for color.

If you reach light yellow or white heat then you risk burning the steel and damaging it. If it starts to spark then you're way past too hot. Don't go past orange heat as viewed in a semi-dark room.
 
Use your file a couple of inches behind the edge. If the edge got a little hot then you might have an area of decarburized steel. The decarburized steel will be softer than steel a couple of hundreths of an inch below the surface. It is hard to tell from the pictures, but if they are giving a true color then you are upwards of 1800 F when you only need to be at 1500 to 1600 F. If you have trouble on the second go round, you can try water. Add Jet Dry to it as a surfactant. Also, test the poll after your quench but before quenching the edge. Good luck and let us know how it turns out.
 
The second attempt went about the same as the first attempt except for about a half inch of the edge of the heel was extremely hard and not fileable. I started thinking a water or brine quench might be in order so thanks for the Jet Dry tip.

Decarburization is an interesting concept. I didn't see Bo T's post before sticking the head in the over for tempering so I didn't file test the poll before the edge quench nor did I file test a couple inches back from the edge after its quench. I suppose its possible to have over heated it and lost carbon from the surface which would mean a lot of file work is in order. Bah! I will try one more heat treat before going crazy with the file on it. Oh, and I will try filing a couple inches back from the edge to see how hard it is back there.
 
Another thought, I was told to use natural hardwood lump charcoal, rather than pressed/formed briquettes. It burns hotter, and more sparks.

I have only done a back yard heat treat on a 5160 knife, but it turned out great.
 
I think your pit forge turned out great. I've read that, for beginners, an open charcoal forge is difficult to master when doing heat treatments. So don't get discouraged. Make sure all the nicks and such are smoothed out before the water quench. Use a larger container for the water. My guess is that; the motor oil is not a fast enough quenchant for your steel, and/or your container of oil is not large enough. Keep us posted. This is a great thread.
 
Discouraged? No. Frustrated? I will admit after the second failed attempt I was getting frustrated but I am better now. I figure its like the work that I do, if it was easy then everyone would do it. I get to learn something from every failed attempt so thats pretty cool. I picked up some Jet Dry today and lump hardwood charcoal too. I am starting to spend too much on charcoal but, what the hell, I hardly spent anything on the axe head itself. Besides, its good wholesome family entertainment. I don't think I will be burning tonight though since its raining and I don't feel much like making a temporary blue tarp shelter.

On the plus side my failures are allowing me to dial in my tempering so when I actually get the quench right I can get the temper right too. Last nights temper went blue.



That was as hot as I can get my oven without setting it to broil or self clean. I figure that setting the dial right between the first and second tempers should result in the perfect purple color.

Do you think a 5 gallon bucket is big enough for a water quench or should I wish up something bigger?
 
I think you had enough oil the first time. If you were quenching 5 axes in rapid succession you'd need a larger tank. But a single gallon will quench one axe.

I don't think I'd use the Jet Dry until I saw what water alone did. An axe bit is thin steel and it's very easy to make thin carbon steel too brittle. Oil leaves a softer core that reduces chipping and cracking but should leave the surface almost as hard as a water quench. Thin steel should be quenched in oil. If oil doesn't harden it then step up to water. Save the Jet Dry and other super-quench formulations low to medium carbon steels.
 
CedarEater said:
I figure that setting the dial right between the first and second tempers should result in the perfect purple color.
Click to expand...

For most medium-high carbon steels (50-65 points of carbon) somewhere in the purple range will be right for an axe. But without knowing what steel you have it's going to be guesswork and file testing to get it right. Once you've got it hard you can do successively hotter tempers until you find your desired softness. Those extra soaks at lower temps won't hurt a thing and actually help reduce stresses in the axes from the quench.
 
Square_peg said:
For most medium-high carbon steels (50-65 points of carbon) somewhere in the purple range will be right for an axe. But without knowing what steel you have it's going to be guesswork and file testing to get it right. Once you've got it hard you can do successively hotter tempers until you find your desired softness. Those extra soaks at lower temps won't hurt a thing and actually help reduce stresses in the axes from the quench.
Click to expand...

+1 And unless you oxidize the steel you can quench many times. One thought, you might heat up your oil to 175 - 200 F before you quench. That will reduce the viscosity of the oil and increase the speed of the oil. Keep moving the head like you wrote earlier. The first couple of seconds of the quench are the most important.
 
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