Replies

1. 
   user-87215 | Jul 02, 2011 03:27pm | #1

   Ian, first, you generally do not need to heat treat a float, I made mine years ago and didn't and they work fine. Heat treating is more important for things like chisels or plane irons that see a lot more use.   You will need to anneal the steel ,  unless you are buying O1 from a retailer, in which case it will come annealed.  To anneal it, you want to heat it to cherry red, then let it cool very slowing -  buy some lime at the nearest hardware store - they sell it in the gardening section, and put it in a container, once you heat the steel, stick it as deep in the lime as possible, and the lime will let it cool very slowly,  another option is to head the steel with your propane torch to red hot, then throw the metal in a charcoal grill while the coals are very hot, and don't take the iron out until the next morning.  Since you don't need to heat treat, yes you can use your old files, though you need to anneal all of the file you want to cut for teeth, so make sure you get the whole thing hot.   Good luck with your work - fortunately, floats are not that hard to make.  

1. 
   CedarGroves | Jul 05, 2011 06:38pm | #2

   This is why I love this forum - great info. I figured floats would be one of the easier metalworking projects I could undertake and as a bonus I should get a few new tools out of the deal.... I was thinking about heat treating after I read an article on the wkfinetools.com pages that reccomended heat treating to give better edge life - since I do not have a set of floats already, I have no idea what kind of edge life I'm looking at for heat treated/non-treated steel.

   About this annealing... I don't see a way to heat the whole file evenly the way I am currently equipped - seems one end will invariably begin to cool before the other end is at cherry red. I only have one mapp gas torch and I'm trying to work a piece about 1/8x1x7".... would adding another torch give me enough heat? I thought about making a small propane forge with some mild steel, stove insulation and a couple gas fittings, but that seems like the slippery slope into blacksmithing lol.  

1. 
   lwilliams | Jul 05, 2011 10:53pm | #3

   If you plan to use the floats much, my advise is to harden them and temper them to a hardness of about RC50. This way they'll be easy to sharpen with a file but hold a good edge for a while. I wouldn't try to harden something the size of a float with a MAPP torch. MAPP torches have a pencil-point type of flame and it'll be very difficult. if even possible, to uniformly heat the steel and to avoid burning portions.You're going to need something with a lot bigger flame to be reasonably successful at heat treating a float. I doubt two MAPP torches would do the job but they'd surly make everything more dangerous. I understand you're trying to do this inexpensively but you need to think out the process before trying two torches. At the very least make sure one is securely mounted and you can  control the other. BTW, I have made a lot of floats and have a pretty good knowledge of what's involved.

1. 
   CedarGroves | Jul 07, 2011 10:14pm | #5

   This wouldn't happen to be Larry Williams the author and planemaker from Old Street Tools would it? 

   I can see you don't like the torch idea, which I can understand from a safety perspective, but you don't give an alternative - how would you do it? Using a bed of hot charcoal from a grill seems like it would be too hard to accurately control the temperature of the steel.... and I doubt the hot-plates I've used in the past would completely heat the blank all the way through, which would cause other problems. I have used home-made propane forges before, as I mentioned earlier, but I don't want to invest too much time or energy into making/setting up a device to heat the steel.

   Bottom line is right now I need a few floats, but I don't want to put up the cash for a retail version when I know I can make them myself - I'm a frugal Yankee, that just feels wrong to me.

   -Ian

1. 
   joinerswork | Jul 07, 2011 10:38pm | #6

   Ian,

   I made a set of plane floats a while back out of mild steel, and they have worked fine for me thru 3 or 4 planes.  I figured the mild steel was easily enough worked and if need be, re filed to sharp that they would do for my purpose.   I can always case harden them later if they prove too soft.  The product is called "Case-n-it" if I recall correctly.  It hardens mild steel by introducing carbon into the outer surface of mild steel, producing a hard skin.  Do all your sharpening of the tool before case-hardening.

   Ray

2. 
   lwilliams | Jul 07, 2011 10:54pm | #7

   Ian,

   MAPP torches produce a very fine pencil-point flame. You simply can't uniformly heat the steel with a couple of them, you'll end up with burnt spots and other spots that aren't hot enough. The price of admission to accurately heat treat is equipment that can do the job. Properly heat treated floats, properly sharpened, are easy to work with and dull floats or ones that won't hold a good edge cause you to force things and lose concentration on what you're trying to do. I've made floats by hand filing and it's a lot of work, why waste all that effort by messing up the heat treating. If you're planning on making planes, you'll want to properly heat treat the irons anyway. With a small investment, a couple hundred dollars,  and a little knowledge you'll be able to heat treat small tools as accurately as any heat treating shop.

   You might be able to jury rig something but keep in mind a stay in a burn ward is pretty expensive.

3. 
   roc | Jul 07, 2011 11:52pm | #8

   I am not talking about hot plate you have used

   I mean a mass grande electric burner. I am absolutely positive the burner on our electric stove would do it. 220 volt. I wonder it you couldn't rent a 220volt dude like this one. Or a small kiln that jewelers/metal smiths use. http://www.amazon.com/Countertop-Hot-Plate-Solid-Plates/dp/B003AWZHOO/ref=sr_1_5?ie=UTF8&s=home-garden&qid=1310096292&sr=1-5

   Please note this little kiln is 120 v and reaches 2000 º F

   http://www.amazon.com/Paragon-Industries-SC-Jewelry-Kiln/dp/B003YRCOVY/ref=sr_1_3?ie=UTF8&qid=1310096867&sr=1-3-spell

4. 
   roc | Jul 08, 2011 12:45am | #9

   How would I do it ?

   Until I got all off on the electric burner thing I would go down to the shop, put my rose bud tip

   http://www.toughweld.com/products/1419-oxy-acetylene-rosebud-heating-tip-victor-style

   on my OxyAcetalene torch handle, take several fire brick ( used to line big furnaces to protect the walls ) ( is weird light flakey brick ) and make a little place that would allow the steel float to be heated with out the heat dissipating fast and light the rose bud torch tip.

   The fire brick reflects the heat back onto the steel and in no time it would be red clear through.  Grab it with tongs and into the oil or water it would go.

   The rose bud is the equivalent of many sharp torch flames that Larry spoke of all in one place.  The OxyAcet is hotter than the Mapp easily able to melt the steel into a white sputtering evaporating ball of "Oh my look what I just did ".

   I would use the Kiln if I had one.  My shop mate of many years had a kiln but he moved away long ago.

   Kilns are cool.

   Rose buds are cool ( to use ).

   Not sure if you can rent an OxyAcet rig but you  better be trained how to use it or you might have a deep smoking hole where your shop used to be.

   :   )

   Acetylene explodes reeeeeel good.

   PS: ha ha ha

   knowing about the virility of the Acetylene; the first time a big rose bud pops ( and it will pop once or twice ) the operator will either have their claws in the ceiling or have a heart attack.  The rose bud sounds like a little jet engine on the end of that torch tube and when it pops it sounds like a rather large fire cracker.

   Ha Ha Ha Ha.

   fun

5. 
   CedarGroves | Jul 08, 2011 01:09am | #10

   Acetylene is lovely

   I actually have a good amount of experience with SMAW and GMAW welding and cutting with acetylene - when I was in college I was going for a welding certificate before I changed directions. We did some light blacksmithing as well which is where I first saw that propane forge idea I was talking about.... and you're quite right, O2 and acetylene can be very dangerous gases without the proper training and safety considerations - things like chaining your tanks (just check youtube for "oxygen tank rocket").

   My question would be what is the difference between a kiln and a forge? Don't they both serve the same function (as far as heating metal goes)?

   Ray had a pretty cool idea of using some type of agent to case harden mild steel... something I had not thought of. I have a lot of mild steel laying around from various machine repairs and I'm sure I can find something to make with it :0).

6. 
   roc | Jul 08, 2011 01:42am | #11

   Oh you are right. Ha Ha oxygen tank rocket.

   Kiln is cleaner for home use.  Just a red glowing electrical heating element wired to the side of some durable insulation.

   A forge usually involvves burning fuel, coal or a gas, and an air blast to "encourage" the heating process.  Makes sparks too that fly around some.  Not the sort of thing one would have inside without a flew to take the poisonous gasses out through the roof or a wall. Hard to do out doors because you need it kind of dark so you can judge the redness/heat of the steel.

   Yes I have seen the black smith's forge next door to a shop I worked at get very dirty in deed.  Like being in old time London on one of the worst coal smoke days.  Yeck !

   Once the forge gets all going good it is pretty tame.  Takes months to learn just how to do that.  The kiln is : toss it in, turn it on, wait an hour,  pull it out.  No brain involved.

2. 
   roc | Jul 06, 2011 11:54pm | #4

   Three little words

   Electric

   Stove

   Burner 

   (large hot plate)