I use 1/2" x 1/2" dowel pins as pinch rollers to feed hard flat wire. They work but the wear a slight groove in them and the get burnished so smooth that they slip. They are only $0.50 ea. but four a day wear out and they take about 3 minutes to change. Time that the machines aren't running equals about $30/day. Is there anything better? The surface on a new dowel pin is perfect for my application but any smoother would be bad.
You can get HSS in .500" diameter pretty cheap. Maybe try that???
Bet you could find carbide in .500" also for big bucks. That stuff is very brittle, might just break on ya.
Can you stand an extra couple thou? Kasenite surface harden your dowel pins
These ideas are worth just slightly less than you paid for them.
Karl
Half inch solid carbide router bit shanks . I've got a handful that I can send ya , just email me your snailmail addy . My reply-to is good . Cut 'em off with a diamond wheel ...
For some strange reason, there is a bit of lead-drag on the wire from the tempering operation and it bonds to carbide but not to the dowel pins. I like the idea of HSS, I'll look into it. No, I don't have a couple of thou, my design isn't great. I do have a new mechanism in process that will use hardened gears to feed and the preliminary tests are very promising.
I sent a package to "J", I have millions more if they work well. I figured out that with a full pot that the lead stream pressure would overwhelm the cavities and not fill out as well and the valve adjustment is too coarse. With the pot less than half full, it works great.
Great idea! I have tried narrower carbide and there is some lead-drag on the wire that bonds to the carbide but not to the dowel pins, But, it might be a case of surface finish. My address is on "OHIOBRUSH-DOT-KOM" I'll trade you brushes.
Could you set up another set of rollers perpendicular to the drive rollers (like a winch farilead) to guide the wire to an unworn spot on the drive rolls?
Another alternative on a similar line of thought:- Re-design so that the rolls could be indexed across. That way 4" or longer HSS blanks could be used without wasting time on cutting them up. Possibly, if the rolls are continuously inched from side to side, the wear could be evened out to the point where total life is much greater?
Mark Rand RTFM
a redesign so one roller was very hard and the other was sacrificial but easy to change would eliminate most of your down-time.
Thanks. I just talked to "the kid" this morning. he's up past his tail in snow and his diesel truck just became a steam engine. NOT good. It may be a few days before they get a trial.
Karl
Alrighty , I'll get 'em off to you on tuesday . These are all worn or chipped bits from a CNC router machine . But the shanks are undamaged .
On Sun, 14 Feb 2010 02:25:30 -0500, the infamous "Buerste" scrawled the following:
How about feeding it (at a more straight-on angle) between rubber tires, then through the dowel pins? Pre-pinch guides, as it were.
A longer distance between the source spools and the pins might help, too.
-- It's a great life...once you weaken. --author James Hogan
Carbide pins.
They can be had...though they are a bit harder than dowels to find.
Gunner
Whenever a Liberal utters the term "Common Sense approach"....grab your wallet, your ass, and your guns because the sombitch is about to do something damned nasty to all three of them.
Could you get a couple of handfulls case hardened? Is it wear or deformation? It never occurred to me to ask what material dowel pins are made from, but maybe all you need is a length of O1 or W1 drill rod cut to length and heat treated.
Pete Stanaitis
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Gunner Asch wrote:
Did you ever try HSS? How did it work?
Wes
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