Trad Gang
Main Boards => PowWow => Topic started by: TSHOOTER on December 31, 2006, 04:10:00 PM
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I've been wanting to make some metal points from old circular saw blades. I have a couple of "cheap" paneling cutting blades that have become dull and am wondering if they are suitable for tradpoints. I had planned to cut them with a cutoff disk in a angle grinder or try to put the cutoff disk in a tile wet saw. Any advice would be appreciated. Thanks
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(http://img.photobucket.com/albums/v247/theferret111/circularsawbladetradepoints.jpg)
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Thanks Mickey
Do you heat/temper etc or just sharpen?
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Sorry I only had time to post the pic and not espouse on it as I was in the middle of getting dinner in the oven (Dianne is out hunting..a man's gotta eat ya know).
The picture is of some trades by Calvin Peters of Canada. My understanding is the circular saw blades without carbide tips make good trades but not the other. I have only made trades from bandsaw blades which I do not heat or temper, just sharpen, so I can't speak from experience on circular saw blades. Hopefully someone else will have an answer on that for you.
Here is a link to the type of trades I make from bandsaw blading, but the process would be the same..choose a particular head design... tanged models are the easiest to mount but take a 3 or 4 more cuts than a simple triangular shaped trade).
Click on any thumbnail to enlarge and read text.
http://groups.msn.com/ferretsarcherywebpage/makingtradepoints.msnw
and here's a pic of a simple 3 sided trade
(http://img.photobucket.com/albums/v247/theferret111/simpletrades2.jpg)
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I would temper them after final shapeing.
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I decided to try to make some today before work. I let my 8 year old help draw the outline and decided to try to cut them out with my tile saw and 4 inch angle grinder cutoff wheel. I'm sure this voids any and all warranties either expressed or implied but it worked really well. Next I'll need to grind the edges and may narrow the tang a little. Since I don't have any shafts for these I'll have to start on those too!! This stuff never ends does it? :D :D
(http://i90.photobucket.com/albums/k263/tshooter_2006/IMG_5555-1.jpg)
Thanks again for your replies guys. Now how should I go about tempering/heat treating. I saw a thread somewhere about heating on the top of an electric stove until red hot and dropping in a can of burnt motor oil and then putting in the oven for a period of time?? Anyone tried this??
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Oh, Buddy, somebody chime in on this! At the moment, this is right up my alley!
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Looking good so far. I'm interested too. That is one of my future projects.
Marvin
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For heat treating & tempering, make sure you get any grinding work done first (ie; if you're grinding edge bevels, before sharpening)
Heat your points EVENLY over a good gas flame or in the BBQ untilthey reach critical temperature. This can be simply checked with a good magnet. When steel reaches critical it looses it's magnetism. Once you've checked one or two, you should be able to remember the color OK. As soon as they reach the corect color/temp IMMEDIATELY immerse them in veg oil (motor oil works too) Leave themin the oil until they are at room temperature. Be really careful when you quench the steel. The oil WILL flare up.
Once they're all done, put the points in a pre-heated oven at 190-210 degrees for roughly 2 hours. This will draw out the temper & depending on the steel should gve you a hardness of around 55-60RWC. I can't be exact on this, cause all steel's different & tempers at differing temperatures. If you clean off any burnt on oil after quenching, you'll be able to see the steel change color as it goes through the different temp ranges. You want to be looking for a golden-straw color during tempering to indicate roughly 200 degrees.
Once they're done in the oven, let the points cool in the air, then you're ready to sharpen them & give 'em a final polish.
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Sorry, forgot to say.Those temperatures are in Degrees Celcius/centigrade, not Farrenheit
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Oh no Ferrets going modern.... :banghead:
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High quality circular saw blades already have excellent temper in them where as low quality blades you buy these days are made from mild steel and can't be tempered. The old fire-tooth blades are good if you have any of those laying around. But if you have to buy a blade, make sure it says, made from HIGH QUALITY STEEL.
If you can cut your trades out of the good blades without removing it's temper then you can save yourself a tempering job. I haven't found a good high quality circular saw blade that I can't cut out by using those Bi-Metal hacksaw blades that the Napa Auto Parts stores sell. And of course, a good mill file helps for shaping.-ART B
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I GOOGLED TEMP CONVERSION AND FOUND THAT 190-210 DEG C = 374-410 DEG F.
NOT SURE HOW I'LL PROCEED BUT APPRECIATE EVERYONES ADVICE. THANKS
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Originally posted by Art B:
...If you can cut your trades out of the good blades without removing it's temper then you can save yourself a tempering job.-ART B
However, does anyone know if those circular blades have the same hardness/temper from center-to-edge? The colour looks different, and if so, you'd want to change your cutting layout so that the front of your heads was at the circumference of the circular blade.
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Temper seems to be pretty consistant throughout Allen. Most times it's just the teeth that gets a little extra tempering for better wear. But as I mentioned, some of these cheaper blades that are produced today are made from mild steel and can't be tempered. Easy to check and see what kind of steel you've dealing with. Just heat up the tip (cherry red) of your trade and quickly cool in water. If it will then take a file cut then it doesn't have any carbon content. If it becomes brittle and will not take a file cut then that's what your're looking for.-ART B