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Made this in 15 mins, upcomming project

Posted: Sat Jan 28, 2012 10:17 pm
by discovershashank
Well just had to sharpen the edges, perfect for box cutter, sits in wallet nice, sharp(gonna heat treat tomorrow), not sharp on the top so can't stab myself :wink: . Let me know if you like it. BTW this is the spring steel from a Smith and Wesson folding nife which was a piece of junk. The original project is to make a small fixed blade knife out of the folder blade.


I WILL UPLOAD THE PICTURE OF THE BLADE FIRST THING TOMORROW. Will appreciate if some once can suggest a design by probably shaping it our own windows paint or some photoshop, I have been told about a place where they have the right tools but I am planning to use a file kit I am gonna get in a couple of days, maybe tomorrow itself.

Re: Made this in 15 mins, upcomming project

Posted: Sun Jan 29, 2012 12:32 am
by marthandan
dont sharpen the knife before heat treat. the edge will burn away if it is too thin.

Re: Made this in 15 mins, upcomming project

Posted: Sun Jan 29, 2012 4:40 am
by discovershashank
Thanks so much fir the positive input, would remember when working on real projects.

Simple but Great input

Re: Made this in 15 mins, upcomming project

Posted: Mon Jan 30, 2012 11:04 am
by essdee1972
Cool piece. How do you heat treat at home?

Cheers!
EssDee

Re: Made this in 15 mins, upcomming project

Posted: Mon Jan 30, 2012 11:48 am
by Mark
You heat the steel to a "medium cherry" color. It is about 1850F IIRC. You can tell by the color, but if you do not have anyone to show you the simplest and best way is to just heat it until a magnet will not stick any longer, and there you have it. Now when it is at a medium cherry, immerse it in some oil. Old motor oil is fine a is most anything else. If you do not have oil use water but for small items oil is usually better.

After it has been "quenched", it will have a grey appearance and be hard enough to cut glass but is also very brittle. In fact if you drop it on a cement floor it may shatter into a few pieces. So you need to temper the steel by rubbing it shiny with some sandpaper adn tehn gently heating it with a torch until the metal turns a light yellow to blue tint. Then you are done.

Re: Made this in 15 mins, upcomming project

Posted: Wed Feb 01, 2012 12:29 pm
by essdee1972
Thanks, Mark! What kind of heat source do you use? (I currently have only kitchen heat sources - gas burner and microwave :)). I have experience of heat treatment of steels at industrial level, but never tried it at home (just like the stunts!). Do you need a gas welding kit?

Cheers!

EssDee

Re: Made this in 15 mins, upcomming project

Posted: Wed Feb 01, 2012 3:39 pm
by marthandan
essdee....a charcoal furnace would be the easiest to set up.
things you need:
1. box made of MS. dimensions - 12" * 6" * 5". thickness >= 6mm.
2. a MS pipe; length >= 24", dia = 1.5", thickness >= 6mm.
3. a vaccum cleaner with a blower option.
4. charcoal.

your local blacksmith will be able to make the box for you, if you cant find one. drill two lines of holes (dia <= 4mm), 12 " long approximately 60 degrees from each other. seal one end of the pipe (need not be airtight). weld the pipe to the base of the box with the open end jutting out of the box...and you have your furnace.

put charcoal in box. light it up. slide the vaccum cleaner hose in to the pipe and your furnace is ready.

you can adjust the vacuum speed to vary the temperature of the furnace. i use a Euroclean ACE model and at full blower speed, the furnace gets hot enough to melt file steel.

have fun.
PS: it helps to have the longest pipe possible. try and have some heat resistant covering between the pipe and the vaccum cleaner hose. else a wet rag will do.
the temperatures get very high and i advise you to exercise caution in the use. please do so at your own risk and i shall not be held responsible for any outcome of your actions. (i feel a bit awkward, putting this disclaimer. i hope you realise that it is risky and dangerous at such high temperatures)

Re: Made this in 15 mins, upcomming project

Posted: Fri Feb 03, 2012 6:38 am
by Mark
The simplest way to do this -reliably- is to do a search on the term "two brick forge" and you will get a bunch of links on things that look like this:

Image

In short, take 2 soft firebricks (they MUST be "soft firebrick", if they are not they will conduct too much heat for a small burner like a propane torch and it will never get hot enough). You hollow out a pair of bricks and make a hole for the torch flame to go in to.

That is all. You can do quite a lot with one of these small forges.

Re: Made this in 15 mins, upcomming project

Posted: Fri Feb 03, 2012 6:56 am
by Mark
Also, before you heat treat it would look nice if you ground/filed the blade into a "sheepsfoot" style tip:
Image

Re: Made this in 15 mins, upcomming project

Posted: Fri Feb 03, 2012 9:39 am
by Moin.
Mark wrote:The simplest way to do this -reliably- is to do a search on the term "two brick forge" and you will get a bunch of links on things that look like this:

[ Image ]

In short, take 2 soft firebricks (they MUST be "soft firebrick", if they are not they will conduct too much heat for a small burner like a propane torch and it will never get hot enough). You hollow out a pair of bricks and make a hole for the torch flame to go in to.

That is all. You can do quite a lot with one of these small forges.
Hi Mark;

What does the little Troll in the pic do ? Temperature Control ? :mrgreen: :mrgreen:

Regards
Moin.

Re: Made this in 15 mins, upcomming project

Posted: Fri Feb 03, 2012 9:59 am
by Mark
Moin. wrote:
Mark wrote: [ Image ]


Hi Mark;

What does the little Troll in the pic do ? Temperature Control ? :mrgreen: :mrgreen:

Regards
Moin.
He's related to this guy:
[youtube][/youtube]
(You might want to watch this standing up)

Re: Made this in 15 mins, upcomming project

Posted: Fri Feb 03, 2012 10:34 am
by essdee1972
Moin, you stole the words out of my mouth!!

Thanks, Mark & Marthandan! Marthandan, I believe your design is something like our old time clay ovens, with MS instead of clay, and a force-feed air intake with the vacuum. Will a CI bucket work?

And I fully understand the need for the disclaimer. Having conned a university a long time back to give me a degree in Metallurgy, and having worked in heat treatment for a year or so, I realise the inherent danger of such activities!!!

However, since mine's a small Mumbai flat, I think I will take this with due circumspection - don't want to be thrown out of the society for arson!!

Thanks!

EssDee

Re: Made this in 15 mins, upcomming project

Posted: Fri Feb 03, 2012 11:42 am
by xl_target
Best of luck with your project, Essdee.

Mark, I almost fell out of my chair laughing at your video. Yes, I know you warned us to stand up. :lol:

Re: Made this in 15 mins, upcomming project

Posted: Fri Feb 03, 2012 11:51 am
by marthandan
essdee...yes...its a "portable" version of the clay oven :D ... and the easiest and cheapest that we can set up in India.
"Having conned a university a long time back to give me a degree in Metallurgy, and having worked in heat treatment for a year or so"...oops!...my apologies if i sounded like teaching a lay man.

a CI bucket might not be thick enough. it might need a layer of clay on the inside.

mark...no offense...but the propane torch furnace would be more expensive and difficult for us to set up.we get everything in India but you will have to search for it and, most likely, will not be available in "hobby" quantities...if you know what i mean. the advantage of being in the USA is that you can walk into Homedepot and get everything you need...or you can order it online.

Re: Made this in 15 mins, upcomming project

Posted: Fri Feb 03, 2012 1:35 pm
by Mark
Ok, well if you want it simpler and you have access to a scrap yard and you have "real" charcoal and not briquettes:
This stuff:
Image

and not this stuff:
Image

find a "squirrel cage" blower like this:
Image

And set it on the ground and attach it to a meter or so long section of pipe which can be anything, even soft drink cans with the ends cut out. Cover the pipe with dirt, then build a fire with some sheets of paper and cover with charcoal. Turn on the blower and regulate the draft with a piece of metal, wood, or cardboard over the intake of the fan. You can find these fans in scrapped electronic cabinets and microwaves to name a few, any size will pretty much work. Just have the fire be a mound and that will work. Heat it red then drop it in oil, then bring it inside and draw your straw color on your kitchen stove.