Wednesday, March 18, 2015

Yet Another Equipment Upgrade

I've been meaning to change to a more appropriate metal cutting bandsaw for quite some time now. The one I've been using is actually a horizontal bandsaw that I use in the vertical position. Frankly some of the processes I used it for were similar to driving a finishing nail with a sledge hammer. Now you know what I mean when using the above term "appropriate".

The problem was finding the correct replacement saw. I've know for some time that what I wanted was a very robust saw with a small throat dimension. There was a bandsaw made in Racine Wisconsin years ago that I thought would work but those saws are few and far between.

Assorted bandsaw parts and one rusty table

The other saws that I thought might meet the criteria were the Powermatic 141/143 bandsaws. The 141 is the woodworking version of this saw and the 143 is the wood/metal version of this saw. The difference being the 143 has a gear box for reducing the speed of the blade.

When you begin to look for one of these Powermatic saws it becomes immediately apparent that the 143 with the gear box is priced significantly higher than the 141 wood cutting saw. On average the difference in price was about $1000. Must be some kind of great gear box huh?

I finally resolved myself to look for a 141 saw with the idea of replacing the motor and drive system with a new C face motor that I would bolt up to a speed reducing gear box. These parts are available off the shelf and the drive transition wouldn't be very complicated.

Here's the saw as I received it from the prior owner
 I put an ad in the "Boyd" forum of the OWWM site stating that I wanted to buy a PM 141 bandsaw. I got a reply from a gentleman that stated he did not have a 141 but he did have a 143 he would be willing to sell. At first I thought I was right back where I started from until he told me the price for the 143. It was reasonable and quite fair and so I agreed to purchase his saw.

I organized all the parts into subassemblies and kept all the related parts together in boxes. As I dis-assembled the saw I also made a list of hardware I would need to re-assemble the saw. Upgrading the hardware on a machine restoration of this type is a sure fire way to enhance the overall look and quality of the machine when completed. I used button socket head screws with the black chrome finish applied the same way I finished the hardware on my PM 90 lathe.

The $1000 gearbox
  Most bandsaws of this size have a casting that consist of a the bottom drive area of the saw with an arm extending up and over the table. The entire back facade of these little Powermatic saws are one very robust webbed casting.

This saw first resided in the Bay area school system shop. This is the area around Panama City, Fla. I guess when the school closed down the shop all the machines were stored in a non climate controlled area. High humidity and salty air are not good for machines. I have no idea why every tool that comes from a school shop has been painted and for some reason the accessories are always missing. No rip fence or miter gauge was included. This saw must have been in a corner when it was painted because it only seemed to be painted on the sides that were easy to access.

Besides the rust this saw was full of sawdust and some kind of strange white residue that looked like it might have been the dust from sawing some form of plastic or other man made material. When I broke the saw down to fit in the back of the car the oil from the gearbox spilled and combined with the saw dust and the mystery material that was in just about every nook and cranny of the saw cavity. I'm glad I laid down 3 layers of poly film in the car beforehand. Fortunately all the functional stuff like bearings and tires seem to be in good shape. That certainly helped to speed up the restoration.

My original plan was to just set the saw up and run it as it was for a while so as not to upset the schedule of work I had planned for the shop. The more I thought about this and the oil soaked material that was in the saw I really feared that sparks from metal cutting might well set this saw on fire. I didn't really want to be that guy that had a saw and a good bit of his shop burn up right in front on him, so before I took the other saw out of service I set about dis-assembling this saw. The next two weeks I spent evenings and weekends restoring this saw.

This saw is built around the main casting so it needed attention first. I cleaned the interior of the casting and was surprised to find sand in some of the corners from when this piece was cast. In lieu of removing the sand it was just painted right over when this saw was manufactured. I first painted the edges of the casting and then painted the interior the contrasting black color. Of course I removed all the lingering sand.

The result of my efforts

 The rusty table now has the nice gray patina that is left when the rust is sanded away and the newly exposed surface is waxed.

All the under parts or basically any parts that reside in the shadows in this saw were painted satin black. The other parts were painted Rustoleum Sage Green. Parts that were not painted were finished with cold gun bluing, then waxed and polished.

I left the wheels the original gold color. It's a nice contrast when you open the wheel covers/guards.

So far this saw is doing it's job quite well. Cutting metal requires more feed pressure as compared to cutting wood and being able to use the leverage of my body weight makes applying the feed pressure much easier. That makes for less toll on my arms and shoulders.

If you frequent the OWWM forum you may know that these saws are sometimes referred to as the "Gumby" saws. If you look at the pic of the Gumby action figure below it's easy to see why. 

Gumby with his sidekick Pokey

My definition of an intellectual is someone who can listen to the William Tell Overture without thinking of the Lone Ranger.