[Whizbang]

Hey, so back in April I bought this old school belt driven power hacksaw. It's actually in pretty decent shape considering the age, but I do have a few issues I could use some advice on.





First of all I have alot of pitting on the once bearing finished portion of the saw arm. It is pitted pretty bad in the areas that were not in contact with the two arm mounts. Any ideas on how to repair this? I plan to make some adjustments so I can get more sawing range in which case the pitted could become a problem.







Another problem is that I think I will need more tension on the flat belt. I plan on making a spring loaded adjustable roller

I found the manual online for the hacksaw. Mine is before the print of the manual it is patented 1912

Any advice and suggestions is much appreciated. Thank you.

[harryn]

If you don't mind it becoming more modern and loosing some of its "originality", the life is easier.

Those older saws were from the day when the whole shop was run from one engine / motor, and power was distributed using overhead shafts and drives. There was a car mechanic in my home town that still used that kind of setup well into the 80s believe it or not.

A modern polyurethane flat belt has a lot more transmissive power, and there are others that might be even better for a flat drive seutp. Worst case, you can swap the pulleys out for a toothed pulley.

If you are willing to drive out that square shaft, then it could be cleaned up, chrome plated (to fill in the pits) and put back to use. Driving out a shaft like that could be a real challenge.

If it is just for hobby use, you could potentially get away with just cleaning out the rust, and using a good quality epoxy to fill in the pits. That is just a guess on how well it would hold up though.

[Whizbang]

If you don't mind it becoming more modern and loosing some of its "originality", the life is easier.

Those older saws were from the day when the whole shop was run from one engine / motor, and power was distributed using overhead shafts and drives. There was a car mechanic in my home town that still used that kind of setup well into the 80s believe it or not.

A modern polyurethane flat belt has a lot more transmissive power, and there are others that might be even better for a flat drive seutp. Worst case, you can swap the pulleys out for a toothed pulley.

If you are willing to drive out that square shaft, then it could be cleaned up, chrome plated (to fill in the pits) and put back to use. Driving out a shaft like that could be a real challenge.

If it is just for hobby use, you could potentially get away with just cleaning out the rust, and using a good quality epoxy to fill in the pits. That is just a guess on how well it would hold up though.

harryn, thanks for the advice. I have the original manual for the machine showing all parts for the overhead belt drive and the electric motor version. however the square shaft on my machine indicates it was one of the first run versions, the squared shaft was fitted to the c part of the saw then the pin was chilled hammered in place then welded or brazed. I have tried removing it and its going nowhere. i am afraid of damaging it if i torque on it anymore. A friend of mine said to sand blast it and then fill the pits with a devcon metal but i am not very familiar with these compounds. I was thinking about electrolysis in a plastic trash can to remove the the rust. But then I am still stuck with a pitted sliding surface that needs repair. I am afraid damage would be done if I tried to run this machine at its full stroke going over those pits.

[packrat]

Think of the pits as "grease grooves". Is long as there is no actual rust in them it really shouldn't hurt anything. The square is just a 'guide' for the C (blade) frame and doesn't move at a high speed.

How are you increasing the stroke? Most have a fixed, non adjustable stroke.

[Whizbang]

Think of the pits as "grease grooves". Is long as there is no actual rust in them it really shouldn't hurt anything. The square is just a 'guide' for the C (blade) frame and doesn't move at a high speed.

How are you increasing the stroke? Most have a fixed, non adjustable stroke.

If you look at the second picture down there is a linkage between the C and the shaft connected to the fly wheel from the image all you can see is the bolt but u can intact loosen that bolt and slide it in the slot to get a more aggressive stroke. When i get a chance ill snap a better pic. I am currently away for a day or so. But will get a pic asap.

[wizard]

As to the pits are you certain that they will even come into contact with the bearings? From what I can see the bearing surfaces are good.

I might suggest rerouting the jack shaft and drive so that it isn't under the saw. That to avoid oil, chips and lube on he belts.

[handlewanker]

Hi, the easiest way would be to remove the C frame and square shaft from the machine and just draw file the slideways until you get the pitted area clean, square and parallel all the way.....this is a simple manual fitting job and will cost you nothing but time.

The adjustment is by the blocks on top of the square shaft that have angles cut into them to take up the wear on the square shaft.

Just make sure you mate the blocks to the square shaft when the rust is all filled out of the shaft.

BTW, the flat belt drive is crap....it has 1/3rd of the circumference of the small pulley in contact with the belt when driving, whereas the large pulley has 2/3rd of it's circumference in contact when driven....the small pulley will slip on the belt as soon as you put extra loading on it.

If'n you're intending to use this to get a larger cut area...(extra stroke length).....better to sell it to a collector and buy a decent band saw.
Ian.

[harryn]

If'n you're intending to use this to get a larger cut area...(extra stroke length).....better to sell it to a collector and buy a decent band saw.
Ian.

There is some truth to this statement.

Those belt drive units are a real hazard, so be really careful to not ever have loose clothing near them. A lot of people have been injured by open drive systems like that. Keep kids far away.

As you have seen, removing that shaft (or most anything on that saw) will be "challenging". Fix it "in place" with an epoxy like devcon with a steel filler. Just practice using it on something else first, like a random flat piece or rusty steel or hot rolled. A few tries with that and you will gain confidence, and it is pretty cheap (available at most hardware stores).

[R90/6Rider]

Nice looking old saw! Who manufactured it? It would be a fun project to restore and or modify. Most folks abandoned using these reciprocating power saws for good reasons. They were relatively slow cutting, inefficient, and hazardous to run compared to the more modern band saws that replaced them. Not something I would want to run, as is, in a home shop or anyplace where small children might be on the loose.
If the pin is all that holds the square shaft in place, I would not attempt to torque, drive, or press the pin out, especially if it is welded or brazed in. I would not want to risk chipping, denting, bending, or cracking a cast or forged part. Carefully drill the pin out. The square bar shaft and pin would not be difficult or expensive to replace with new parts identical to the original. If I were going to put this saw back to work I would consider getting rid of the flat belt, use modern belts and pulleys, and fabricate some simple plexiglass guards so you could still see all the moving parts and enhance safety. Even if you don't normally have small kids around, it is amazing how quickly visitors and neighborhood kids explore anything and everything they can possibly get into.

[RICHARD ZASTROW]

Or clean the pits and "brush plate" the pitted area with electroless nickel. You can plate with almost any metal that you would normally plate by plating in an electrode type tank.

Did a lot of "oops" and wear repairs with brush plating in another life.LOL It's used a lot to do on-site field repairs.

Dick Z

add: www.sifcoasc.com

[Whizbang]

Guys thanks for being so active on this thread.I will take the safety concerns into account. The reason I bought this saw cause it looked.sweet and power hacksaws produce great cuts. I have 2 to 4x6 bandsaws one is 20 year old wholesale tool and a 15 year old chicago saw these are the saws that are nearly identical to the harbor freight ones but the castings are a lot thicker. I can't find a replacement brass gear for a reasonable price I will post pics of those saws when I get a chance I just feel like the band

saws have cuts that walk too much

[wizard]

One reasons is the history. It is rather sad that some rather unique industrial hardware has disappeared from the face of the earth. These are machines that literally built America.

The second reason is to embrace simplicity. Often these machine are simple in the extreme, as such they are a lesson in solving problems without the complexity that is often put into today's hardware.

Third is the simple fact that many machines aren't made today.


I'm in agreement with respect to safety, but I do wonder about the issue of kids. Frankly these machines are not anymore dangerous than anything else in the shop built today. Like guns, kids and machine tools don't mix at all and should never be allowed near a shop unsupervised. In any event this isn't to an attempt to discount the real safety issues of these machines for the operator. Making the machine safer isn't an insurmountable problem where a little bit of guarding goes a long ways.

Guys thanks for being so active on this thread.I will take the safety concerns into account. The reason I bought this saw cause it looked.sweet and power hacksaws produce great cuts. I have 2 to 4x6 bandsaws one is 20 year old wholesale tool and a 15 year old chicago saw these are the saws that are nearly identical to the harbor freight ones but the castings are a lot thicker. I can't find a replacement brass gear for a reasonable price I will post pics of those saws when I get a chance I just feel like the band

saws have cuts that walk too much

[LUCKY13]

The pits will not hurt a thing, just be sure and get the rust out of them. They will act like little oil pockets for the grease/oil and it will even reduce friction on the slide. Clean them out, run a stone/hone/sandpaper or it so it has no wrough edges and it will be good to go. Ready to work for a nother 50 years.


Jess

[Whizbang]

As promised here are more pictures of the discussed topics
1) increase of stroke pictures
2) my other two horizontal bandsaws

1:




This extends the linkage and changes the stroke.

And now for the band saws. I have checked one is from wholesaletool the other is central machinery. I got them from a guy who bought the WT one 25ish years ago and when the gear went bad bought the newer central machinery one but the gears do not connect the same and the central machinery one is of a lower quality. I have disassembled the WT one removed the brass gear and also made a mold of the worm gear and taken it to appliedtech. they want near 100 for the brass gear and i would still have to put a slot for the key and the hole for the pin so i haven't done anything with them because i can nearly buy a new one on sale for $50 dollars more.

2:








and for the second/newer one



https://lh4.googleusercontent.com/-Z...0/P1020413.JPG

[wizard]

If you have a lathe you might be able to make your own worm gear, but even going the DIY route you still have to contend with the cost of materials unless you have the goods laying around. It is a sad reality that it is often more cost effective to replace than repair these days. In any event you can find videos on the net that show the lathe hobbling process for worm gears.

In one of the pictures it looks like the gear box is of the bolted on type in another pic it looks casted in place. Either way you might want to look into a surplus ger box if you can find one. If casted in place you would have to mill off the old gear box and bolt on a new one. Again lots of work and frankly probably not worth it.

I had to make similar decisions recently with respect to a belt sander. By the time you are done replacing bearings and numerous other parts you can have a ready to go model for for nearly the same price. This is especially an issue if you don't have lots of time to pursue a rebuild. In the end your time is probably better spent on the old hack saw as that would bring a unique and hard to replace capability to your shop.