Yesterday when I got that CI stove door from the neighbor , I also loaded up his hand cranked forge blower . I've got it pretty much stripped down now and Houston , we have a problem . There are some gears in the drive , straight cut spur gears and one helical ... and the last gear in the train is a small helical and it is badly worn . This gear is machined on the shaft as one piece as far as I can tell , and I'm very doubtful it can be replaced . I'm not sure just how old it is , but he said it was his grandfather's blower from his coal forge - which the guy also has in his shed . Any chance one of you guys has a source for parts for antique forge equipment ? If I can't replace the shaft I guess I have a couple of options : I can very carefully TIG up the teeth and hand fit the gear , or if I can find a gear with the proper pitch and angle I can fab a new shaft . Everything else is just straight replacing screws and machining a couple of bushings .
Another project
Dec 01, 2015
17 Replies
Not up to learning to cut gears, starting with small finicky ones?
If you can get the shaft out as a bare item, could you weld up the teeth and trade favors with someone who _can_ cut gears?
Or if you're really lucky, you could find a mating gear to put onto the shaft (assuming you don't have to cut away too much of the shaft to do it).
Tim , I have no problem cutting straight cut gears . In fact , a couple of the gears in my lathe QCGB were made right here by yours truly as were the gears in this 9:1 reduction set .
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which is closer to finished than those pice show .
Helical gears are an order of magnitude or two beyond what my tooling will do . I have no way to rotate the work in synch with feed .
I would check ABANA websites...many local groups across the country. Might want to google the manufacturer of the blower and see what ebay has for sal e. I look under "blacksmith tools" on occasion. I would think there is a pi n holding the gear to shaft. Best of luck.
You wrote "helical" and it turned into "bevel" inside my head. Probably because I'm an engineer doing accounting (1st day of the month is Billing Day) -- trying to do financial stuff always scrambles my brains.
I wonder if someone over on the Gearotic forum might be willing to help
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. I suspect you'll have to sign up and post a message and see what response you get. Obviously you would have to identify the gear DP/module and helix angle.
The blower was made by Belknap Hdwe & Mfg Co , which means it was made between 1907 and about 1940 - and I was mistaken , it was originally the neighbor's great-grandfather's . The mfr is out of business and I can find no reference to their making forge blowers . The gear is definitely not pinned , the minor diameter of the gear is the same diameter as the shaft . It's looking more and more like I'll be doing some delicate TIG welding ...
That sounds a lot like a Buffalo No.200 "Silent Geared" blower.
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The gear system looks pretty damn close , do they still make parts for these ?
Toss a couple pictures up. There are folks who make parts for specific ones but you need to know who's blower you have.
The Buffalo company is still around BUT they don't carry parts for the old blowers.
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I looked at those last night . I'm not sure how much he really wants to use this , I think he just wants it to work so that he can use it if the need arises . Probably a big part of the wear is because the bushings are totally shot . I'm going to address all the other issues before I decide whether I'm going to attempt repairs on the gear itself . Since I have no idea of how many hours this thing has on it , that gear may outlast Randy ... If that gear weren't helical I'd just machine a new shaft ...
Can you replace the other helical gear?
-jsw
Those old hand-crank drill presses are kick-ass and they work well.
This is the perfect opportunity to ask the little lady if you can buy a metal-sintering 3-D printing machine. ;)
I can probably replace it with a straight cut gear ... but I won't know for sure until I get the gear box apart , got a couple of stuck screws I don't want to bugger up .
If you don't expect to use it a lot you might be able to build up the gear with a torch and brazing rod, although TIG is nice for free-hand sculpting.
Perhaps you could take an impression of the other gear rolling against a warmed wax or hot-melt glue blank, mold a negative of a tooth on it in fireclay and use that as the mold to fill in the worn teeth. Even
95/5 solder might hold up well enough for a while as gear teeth, I've used it to cast tooling fixtures and it's hard enough to take threads reasonably well.-jsw
Here's a story I wrote last year about Buffalo tube benders. This one was used in the restoration of the Statue of Liberty:
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That was the first job I shot with my (then) new Sony NEX-7 camera. It was love at first click. I have a better flash setup now than I had then.
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