Restoring an old power hacksaw – Part 1

Posted by on November 25, 2014

A power hacksaw you say?

I always wanted one of these machines, this particular unit was based on a patent from circa 1890, amazingly these machines still have a spot in our hearts, and shops.

After many weeks of looking for one I managed to find a power hacksaw that was both in good shape (read: no missing parts, more on this later), it was listed for an “OK” price and it was also located somewhere near me, so I could have it delivered for a reasonable fee.

Despite what some people in general told me (“avoid this, buy an import bandsaw instead”) I went ahead and pulled the trigger on it. I’ve seen the import bandsaws and they require the same amount of work, or more and it is still a weak little thing that will fail sooner than later. Don’t get me wrong, most of them are meant for hobby use and will probably work fine for you after an adjustment or two, I just don’t like them.

And it arrived on my birthday!

This is what I got fresh out of the truck after a quick wipe-down…

Some assembly required...

Some assembly may be required…

 

The dovetails looked fine, there is some visible wear on the gib, but this was expected.

The dovetails looked fine, there is some visible wear on the gib (not shown) but this was expected.

 

Now THIS is what a 3/4" HP single phase motor should look like, at least size wise. Unlike the China crap we see these days with extruded aluminum body and two end caps made out of recycled pea cans this thing is all cast iron and steel, yey.

Now THIS is what a 3/4″ HP single phase motor should look like, at least size wise. Unlike the import crap we see these days with extruded aluminum body and two end caps made out of recycled pea cans this thing is all cast iron and steel, except for the pulley.

 

partially assembled, checking the wear on parts -- This needs to be addressed.

Partially assembled, checking for wear on parts — This needs to be addressed.

 

A bit of history

According to the guy who sold it to me, this machine used to be “blue” — However I was able to count at least 4 different colors after sanding one part down, who knows how many people owned this thing, for how long, where it’s been… how many parts did it cut?, we’ll never know!

I do know this belonged to his dad, he was what I would call a general fabricator / welder and I know he bought it used already.

I’m thinking this might be from the 50s but could be slightly earlier, sadly it doesn’t have a hydraulic feed, just gravity.

What’s wrong with it?

All the parts were  there, except for the depth stop. Oh well, that’s the least of my concerns right now given the wear on some of these parts, I’ll have to figure out a way to fix them at least temporarily…

 

  • The upper belt does not fit properly and thus slips under load, the lower belt is brand new and fits perfectly, so that’s good.
  • While the dovetails can be adjusted for wear/play, everything else can’t — The machine uses simple bearings (steel on iron, with grease ports) wear does occur and given the nature of this design, some parts end up being oval, which makes it even harder to fix without major machining.
  • The motor needs new bearings, it sounds terrible but the start winding works fine and the centrifugal switch also works properly, so not all is bad.
  • Conrod has play, the holes are not round anymore!
  • Wiring, terrible job and no PG / Ground, what the heck. Needs an upgrade, although I’ll keep the Bakelite switch, since that is part of the automatic shut-off and also, original to the machine.
  • Motor pulley is not running true at all. This was NOT the original motor. The machine most likely came with a 1HP 3 Phase motor as it was quite common back in the day.
  • Color, this would not be my first choice. Plus they did a terrible job painting over the old paint and rust.
  • I’m sure there’s something else terribly wrong with this machine but I haven’t found out yet.

 

First cut

Despite the machine sounding like an engine with a set of loose valves, broken rings and a bent con-rod I managed to get a relatively good first cut after assembling it. Clearly we’ll need a coolant system for this puppy…

So it cuts... but slow. OH WAIT A MINUTE!! -- They mounted the blade the wrong way around!

So it cuts… but slow and it vibrates a lot. 2″ round aluminum rod, 20xx series

Slow?

Turns out the previous owner mounted the blade the wrong way around… But this was a new blade, odd. He handed me three blades in total, one worn (trash) one fine, one coarse (installed). I can’t help but wonder if they used this machine like that all the time, or if he just wasn’t paying attention when he swapped the blade prior to the delivery.

At any rate, the machine now cuts as fast as a power hacksaw should cut, with a coarse blade. At least the vise seems well trammed, I noticed some shim stock underneath, interesting. We’ll measure how well it cuts later on.

For now I’ll focus on minimizing the play on the main parts of the machine, replacing bearings, etc.

Paint can wait!

 

To be continued…