I've got one of the HF step bits, which I'm trying to use for drilling a
1-3/8" hole. So far I've managed to coax it into cutting up to the 1-1/4", but the 1-3/8" step doesn't seem to be up to the task.
I know a regular file isn't the right tool, so I'm guessing I'll want to take a flat stone to it (?), but where? Down the "cut away" part of the bit, or tangent to the outside circumference of the bit?
Stone the flat surface . I've done this on router bits when they aren't too dull and it's amazing the difference it can make . If you stone on the round it'll alter the cut diameter ...
I've had a go with a Dremel & a grinding bit. I wasn't too successful but that may have been down to my poor technique. I reckon it would work well if you had a good hand.
This is what "slips" are made for. Slips are narrow sharpening stones, and they come in various shapes -- rectangles, pyramids, and long cones are the common ones.
I have them in grades from Medium India (Norton's aluminum oxide) to white hard Arkansas, and they get a lot of use in honing lathe bits; knocking the turned edge off of drill bits; and even sharpening serrated kitchen knives.
They're something that every machine shop used to have on hand. A common use for them was fitting and honing punches and dies, but they're useful for many things.
If you're going to try using a Dremel, try cutting with the edge away from you, rather than the usual stoning direction of cutting with the edge close to you. Then you can use a fine sandpaper disc or a cutoff disk, which will give you more speed and a much finer touch than most of the wheels. You can have really good control that way. You also will shatter some cutoff disks, so eye protection is especially important.
You may get a slight turned edge that way but you probably won't, unless your bit is really too soft. The turned edge is easy to knock off if you encounter it.
Yeah, the Arkansas versions are getting so that I want to lock them in a vault. I've got India slips that do almost as well, good enough for most of the rough work. They make ceramic ones that work just about as well as an Arkansas stone now, for about a 1/3 of the price. I've got some small diamond hones that work well enough for sharpening stuff like the step drill, work fast, too. I wouldn't use a hand grinder on the step drill, myself.
I've never tried the ceramic stones, but I want to. I have so many traditional stones of all types that I can't even count them, but I'm always interested in something new.
I think that diamond stones are cheating, like sharpening my fillet knives with my wife's motorized kitchen sharpener. d8-)
========================================= Cheap but Good Honing Oil Recipe: 90% kerosene, 10% motor oil.
Better-Smelling Honing Oil Recipe, for use in the kitchen, and by wimps: 90% scented lamp oil, 10% motor oil.
Cleaning the glurp out of an old oilstone: Heat in a toaster oven that you don't ever want to have in the house again, at 250 deg. F for an hour. Wipe off with paper towels. Bon appetit.
I have alway understood that the reason for using oil for honing was to prevent the stone from becoming clogged. So thought using detergent oil might be better that non detergent oil.
But skipped straight to using detergent, namely Dawn and water. Seems to work well for me. The stone does not become glazed. And a glazed stone can be cleaned with water, detergent and a tooth brush.
I've also used dish detergent in the kitchen, and it does help keep the stone unclogged, but the lubrication of regular oil is supposed to extend stone life, too. I don't know; I havent tested it.
However, when I'm really laying into it, like taking the belly out of a chopping knife on a coarse stone, I've noticed that it cuts much faster when well-oiled.
With the cost of stones today, I don't take any chances. I use honing oil.
Another great way to clean stones is with an ultrasonic cleaner (15 min in detergent solution, 10 min rinse in clean water, let dry). I got a good Branson cheap off ebay a few years ago and have been finding all sorts of uses for it. It can even (supposedly) age your wine:
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tried that in my Branson cleaner, it definitely changes the taste but not always for the better. I think it mostly just removes the dissolved gasses making it flatter.
That is cheap. The customer reviews are generally good, but these cheap models usually skimp on ultrasonic power and have a lower frequency. The better models also sweep the frequency slightly so the nodes of the standing waves move around to insure everything is cleaned.
I will be the Designated Wuss then. Considering the amount of involuntary blood samples I donate (when using a blade well past it's expiration date), I think a straight razor would be lethal. :)
That's the kind I used, to trim the downy fir I was pleased to call a beard many (cough MANY) years ago.
If you promise not to tell anyone, I will confide a secret. As recently as last year, I asked for one of those at a local drugstore. The SWT at the register looked at me and said "Safety Razor? What's that?" :)
She eventually recovered by mentioning that they
*did* sell safety razor blades.
I'm really intrigued to see if those blades can actually be sharpened using the apocryphal glass tumbler or if that was just creative thinking on someone's part.
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