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W. Robertson Mach & Foundry Co. Number 4 Power Hacksaw


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This is where I shall post any work I do to extend the lifespan of this reciprocating cutting device.

In the meantime, here's a video if it chugging along through a jackhammer bit.

First order of business, replace the light switch with a proper 20A switch.

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  • 4 weeks later...

Full disclosure, PHOTO HEAVY. I know you all have been on the edge of your seats. Some of these repairs were done weeks ago, but I neglected to take pictures at the time. Figured it was time to take it apart again and take some pictures/see how things are wearing in.

Most important thing first. When I first got it the bar that hacksaw arm slides along was noticeably tilted when looking down the length of the ways. I don't have a before picture, but here it is after I fixed the problem. The yellow rectangle is about what it looked like initially. The bar itself was straight, but the hacksaw arm was tilted, leading to wandering cuts. Over time this misalignment had led to some very uneven wear in the ways, so much so that the casting had worn away to the front 2 screw holes on the left side.

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The wear surfaces on top appear to be UHMW polyethylene (or something similar) so I bought a sheet of that and cut it to fit the hollow area in the casting on the side with the excess wear.

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Now the bar glides along the polyethylene rather than the casting and there is about 3/16" of wear surface before any additional damage is done to the hacksaw. The cuts are square again. Assuming it stays well lubricated I figure that ought to last another 100 years of use. Note: The dark stuff is moly grease, not worn metallic bits. I cleaned and greased all the parts before reassembling.

On the opposing side there are 2 slots for inserts. There were 2 cast iron inserts in there before, but I replaced them with mild steel with ~0.080" of brass braised on the wear face.

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Now everything is running true and the hacksaw is no longer eating itself while it runs.

The next item, which was really more of an annoyance than anything, was the oil leak coming from the driveshaft for the oil pump. The guy I bought it from said he tried to fix it, but couldn't get it to stop. After I took apart the brass fittings I found that he (or someone) used a shoelace as an oil seal...

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Fortunately, I had a kit of automotive grommets and one of them fit nicely.

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So far the new seal has held up well, no more drips.

I found one zerk, so I greased that up as well.

I love this thing. It's super simple and every part is comically overbuilt. It may be a little loose in the hips, but it chuggs right along. Given a little time it will cut pretty much anything you put in there without much fuss.

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Pork smoothy? :wacko:

We're getting a lamb soon so I dug out the meat grinder for the Kitchenaid mixer and it only takes little pieces so we'll have to dice the meat pretty small anyway. Mother's hand crank meat grinder would take pieces just smaller than my fist. The hand crank was connected directly to the auger, gear reduces are for sissies or high priced power tools. 

Frosty The Lucky.

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