annealing ideas

zaph1 said:
KClO4+AL (flash powder).
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Potassium perchlorate and aluminum is not a safe cannon propellant. Flash powder detonates and does not burn (unless unconfined and in a pile less than 28 grams). For a cannon your want burning, black powder and tri-nitro cellulose both work but tri-nitrocellulose is for high compression and is dangerous to make since you can't normally buy it in pure form. Its the basis for smokeless powder, I'm not sure if modern smokeless powder uses it though.

Also make sure you don't ever substitute KNO3 for KClO4, it will randomly self detonate during storage because of a chemical reaction with the aluminum. :eek:

0.1g of flash powder will remove fingers, 1g will remove the entire hand. Be careful with that stuff.
 
Thanks,Dan. Pretty much my sentiments,too.
I have had a bit of experience with explosives and rocket fuel..... and a lot with flash powder ( stage effects). I have shot my share of cannons,too. I thought the same as you, but he said he is 37, so I let it go. Darwin has a theory about the misuse of black powder.

FWIW, we used 2fg on small bore signaling cannons, and cannon powder ( I assume it was 1fg) on larger field pieces. For stage effects I used 4fg to get a lot of smoke, and commercial flash powder blends for light with less/no smoke.

Funny that this should come up. At a family dinner recently, my son-in-law asked about a red cylindrical object on the top shelf in the garage ( they live in my old house). He said it was marked "4fg only". It was one of my old flash pots. I kept the ones for black powder separate from the ones for flash powder to avoid mixing the two.

The fellow who taught me how to do the stage effects used to be the F/X man for a big staging production company, back in the 60's and 70's. He worked with Stevie Wonder on one occasion.They would put Stevie on a stage elevator. When the band was really rippin', the F/X man would set off the flash pots, then the smoke pots. Stevie would be raised up in the midst of the smoke. He would appear to materialize out of the smoke to the audience.
After the concert, everyone was at a huge party at the promoters house. My friend was invited to come along. During the party Stevie was hollering ,"Where is Sam?" My friend ,Sam, came over to see what he wanted.There was a fairly well known basketball player at the party. Stevie had challenged him to a contest. Stevie told Sam to go to the truck and get a can of flash powder and a waste basket. Sam gave them to him. Stevie took the trash can and put it on the patio by the pool. He poured a LOT of flash powder into the can. He took a cigarette and went to the other side of the pool. He told the basketball player to toss a beer can into the trash can. It took him four tries. When Stevie heard the beer can go into the trash can, he took the cigarette and tossed it all the way across the pool and hit the can with a big flash. I am told that Stevie used to do this trick by putting some flash powder in the sink backstage,too. Sam said that one of the band members told him, "Don't ever give him a full can of powder!"
 
Out of curiosity, would you rate it more or less dangerous than the hair-spray powered potato guns? I don't shoot them, I always thought they were too dangerous using PVC for a cannon. Our tennis ball cannon is made from 1/2" thick aluminumwith a 2" thick area that holds the flash charge.
 
we *HAD* a hairspray cannon till it blew up in my buddies hands, flash burnt him pretty good but no lasting damage Thank God! as long as you dont over charge it it's ok. we have moved on to a potato howitzer, made from a small tralior, a 10 ft pipe, an electric valve and a 20lb compressed air tank :D It'll chuck a tater 1/2 mile!

Jason
 
Enough snow has melted that I COULD get to the bonfire pile, but I would think the wood is awfully wet. 60 minutes at 375, then how should I cool it, just let it cool normally or dip it in water?

JasonSCarter said:
Or get your lazy, cityfied, candy arse outside, grab a shovel, clear a place and ... build a bon fire, roast some weinies and marshmallows, with the family, throw a file into the fire, dig it out next afternoon, (becareful there will probably be hot coals still) now you have a an ANNEALED file to grind a knife out of with the lines still intact. when ready sprinkle some table salt on the blade, and heat back up the file till salt melts FAST. then quench in MCMaster Carr 11 second oil (about 20 bux for a gallon) plunge straight in, no side to side and no yaw one way or the other a little downward angle is fine.

Jason
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if your doing the low temp route 375ºF for 2 hours then let it cool to normal room temp by itself. just shut off the oven and open the door and let it sit till cool.

If you do the hi temp route make sure you put it in the red coales and pile wood around it to create a hot spot. dig it out the next day and your should be soft enough to not have to worry about it.

If you know anyone with a ceramics kiln then your in luck!
Anneal: Heat to 1375 to 1400° F, soak until uniformly heated, approximately., one-half hour per inch thickness. Furnace cool 50° F per hour to 975° F, air cool to room temperature. soft as a baby's bottom, or as close as you can get to that with steel. anyway!

Jason
 
Oooh, I know someone with a ceramics kiln. I will definitely do that. I'm curious if you can tell me how welding on a guard affects a pre-HT knife? Should I anneal the knife again then HT?
 
If you go the kiln route, don't go above 1375°. What you will be doing is spherodizing the carbon, and to go non-magnetic, 1414°, or above, will negate the effect you are trying to get as the carbon will start going into solution, then when it cools, it will form into layers which will not be so soft to work with.
 
Thanks LRB I copy and pasted the annealing instructions in my post for W1 from http://www.buffaloprecision.com/data_sheets/DSW1TSbpp.pdf But your advice is spot on about the carbon getting into solution from 1400F and up solution.

Zaph. . . PLEASE DO NOT WELD A GUARD ON! sweat one on with Force 44 silver solder, pin and peen one on instead. But if you do weld a guard on, do not quench the steel just let air cool to ambiant temp. You should be fine. Make sure to tell your welder to take it easy though and dont get it too hot. you may cause a large grain growth spot which could compromise the integrity of your knife. Unless you normalize again, and for grain resetting and Stress Relief of Unhardened Material: Heat slowly to 1200 to 1250° F. Soak for two hours per inch of thickness at heat. Soak, slow cool (furnace cool if possible) to room temperature. 2-3x

Jason
 
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