Heat Treat ''proper'' blade wrapping ?

[BCROB]

Folks,

went with the Paragon , ordered and should be here in a few days..............
I have been shipping my blades for heat treat until now so I've never really had a hands on blade wrapping lesson. Is there a tutorial available for 'proper' blade wrapping ? with pics ? Also am interested in opinions on type of foil preferred if there is a variety or choice option.

Thanks in advance........

Rob

[Matt Bufford]

No classes really needed.

First the type of foil depends on how hot you are going. If you are treating steels that will be heated to 2000 degrees, then get the high temp stuff. If you are heat treating the 10x steels, get the lower temp foils. Or just get the high temp because price difference is negligible.

I typically start off by completely cleaning my work area of all debris, dust, oils, and any other contaminants.

Make sure the blade is cleaned off completely of oils and other contaminants. I use acetone. Don't touch it with bare hands after it is cleaned. I also wipe down my foil before closing it up. Cut the foil with enough room to fold over the blade and get at least 3 folds for a seam. Fold it up, and roll the seam after every fold until it is sealed up. Some folk like to put a piece of paper in with the blade to eat up residual O2, I haven't ever done it or seen the need to.

Wrap it up in a second layer of foil same method as first, being sure you haven't gotten any finger oils on anything.

I'm sure there are more in depth methods, but I try to keep it as simple as possible. If your seams are good and tight, you shouldn't be letting any air in. As far as the powder stuff goes, I've heard great things, but I've just found no reason to spend any more money when I don't need to.

[Ray Rogers]

Sounds like Slacker has the info on foil, which is good because I never use it. It's like anything else though, once you learn the technique you should get good results. There are also paint on products that serve the same purpose if those have any appeal to you.

I pump argon into my Paragon and remove the need for foil or paint. It probably doesn't work as well as foil in terms of how well it prevents oxidation simply because the Paragon is not air tight so there's always some air in there but it works well enough and it's much more convenient. But, I do all my grinding after the HT is complete so a little oxidation is no problem for me. Just one more method to consider ...

[BCROB]

thanks for replies gents

[Robert Dark]

If you are going with a Paragon and planning on using argon, you need to think "POSITIVE PRESSURE". You will use a tad more argon with slightly higher pressures/volumes, but it will pay off in the long run.

If you decide to "Wrap" your blades, then I think the "double-wrap" is probably the way to go.

Don't ever let anybody talk you into trying to put her into the oven with no wrap or no gas. You can't buy enough belts to grind the de-carb. What might start out as a 4" hunter will wind up as a 2" necker (if you are lucky),

[tuskbuster]

Ray you say you do ALL your removal AFTER ht?.all thickness or just the thinner?

[BCROB]

Originally Posted by Robert Dark

If you are going with a Paragon and planning on using argon, you need to think "POSITIVE PRESSURE". You will use a tad more argon with slightly higher pressures/volumes, but it will pay off in the long run.

If you decide to "Wrap" your blades, then I think the "double-wrap" is probably the way to go.

Don't ever let anybody talk you into trying to put her into the oven with no wrap or no gas. You can't buy enough belts to grind the de-carb. What might start out as a 4" hunter will wind up as a 2" necker (if you are lucky),

thanks Robert for your input........

[AUBE]

I've never tried it but this is something I've wondered about. Argon is heavier than oxygen, so what would happen if you basically had your ht oven sitting inside a box that has airtight sides/bottom then just keep a very slight trickle of argon going during the cycle? It seems like any argon escaping the oven would settle inside the tub more readily than air and keep the oxygen levels low....

There could be a problem with retained heat messing up electronics but that could me mounted elsewhere.

[Ray Rogers]

Yes, I do ALL my grinding after HT is complete. I profile the blade and then it goes straight to HT. Quite a few guys do it that way, it avoids many of the problems that often come up like warpage and concerns about decarb. You need to use fresh high quality ceramic belts but that's just good policy anyway. I use one 60 grit belt per 10" blade, or two smaller blades. Even then, the belt still has a little life left in it. I've done it this way for over 10 years.

No real need to build that air tight box for the oven. I run the argon at 7 cfm all the time that the oven is running for HT (not for tempering) and my 160 cf bottles last me more than a year. Just make sure you have ventilation in the shop because you can't breathe that stuff....

[AUBE]

Originally Posted by Ray Rogers

No real need to build that air tight box for the oven. I run the argon at 7 cfm all the time that the oven is running for HT (not for tempering) and my 160 cf bottles last me more than a year. Just make sure you have ventilation in the shop because you can't breathe that stuff....

Aha, I didn't think it would last that long...I was picturing around 2months. I might end up going the argon route myself. Thanks. (sorry for getting off topic ruger4)

[BCROB]

Originally Posted by AUBE

Aha, I didn't think it would last that long...I was picturing around 2months. I might end up going the argon route myself. Thanks. (sorry for getting off topic ruger4)

please don't apologize this is all very good info ,
especially for newb heat treaters like myself !!

[Ray Rogers]

How long it lasts depends on how much you use it (obviously) and the size of your tank. But, even if it lasted two months I would prefer that to trying to deal with using the oven inside a box. The oven needs maintenance now and then - bricks break and coils burn out. This require you to completely disassemble the oven. And then there's the issue of trying to get the blade out of the oven which is inside the box. Your overall design will affect that a lot but it will always be harder than it is without the box.

One thing that helps me is that my argon regulator is wired into the oven's control box so that argon only flows when the coils are heating. It's not important to have the argon flow only when the coils are heating, it's simply a way to cut down on the amount of argon you use...

[tuskbuster]

thanx ray ,i was beginning to doubt wether i was just using to many belts doin it this way also.it has cut down on my little screwups as far a slight warpin

[10es&]

I highly reccomend using a wooden roller for folding your foil pouches. The seams are much tighter when using one.


Here is an example of one simular to mine.

http://www.secondskinaudio.com/tdc/_...ts/med_256.jpg



Brett

[AUBE]

Originally Posted by Ray Rogers

How long it lasts depends on how much you use it (obviously) and the size of your tank. But, even if it lasted two months I would prefer that to trying to deal with using the oven inside a box. The oven needs maintenance now and then - bricks break and coils burn out. This require you to completely disassemble the oven. And then there's the issue of trying to get the blade out of the oven which is inside the box. Your overall design will affect that a lot but it will always be harder than it is without the box.

One thing that helps me is that my argon regulator is wired into the oven's control box so that argon only flows when the coils are heating. It's not important to have the argon flow only when the coils are heating, it's simply a way to cut down on the amount of argon you use...

My thought was to basically make a topless box with a swing down front door....kind of like a truck bed. The argon *should* pool in the bottom since it is heavier than air. But then the lift from hot air escaping might be enough to lift the hot argon right out too...thats something I hadn't thought of. Maybe it would need a top as well.

Either way I was going to make sure you have easy access to the oven to remove the knives and do repairs.

I'll probably build it the normal way first and give that a try...as they say "if its not broken...". I want to avoid foil if at all possible.