Marvel No. 2 Draw Cut Saw Restoration

[T. J.]

I was recently given this saw. As you can see, it was pretty "crusty". I think it will make a nice addition to my shop when I get it restored. I have it completely disassembled now and I've discovered some issues, which I will present in a later post. For now, here's how it looked when I received it.

 

[T. J.]

I removed the motor first, then I attacked the saw with a pressure washer. I was able to remove the first several layers of crust. There's even some original paint under that "protective film"!

 

[T. J.]

Here's the base casting after some scrubbing and a little wire wheel massage.

 

[brino]

What a transformation!
Can't wait for the next installment.

Thanks for sharing.
-brino

 

[T. J.]

As I alluded to earlier, I've found a couple of issues with the crankshaft. First, the crankshaft bushing has a lot of wear on the crank end, accompanied by some galling on the shaft in that area.

So I will need to make a new bushing and shaft. Now here's the other problem that I could use some help with from someone who has one of these saws. This is a pic of the eccentric on the crank and the end of the lever that rides on it.

It looks to me like the eccentric is severely worn. The yoke on the lever has been repaired at some point by welding, and I figure that the hardness of the weldment is what caused the wear. There is a faint remnant of what I think was the original outline of the eccentric visible. Its diameter is roughly 2-5/8", which cooresponds with the size of the yoke on the end of the lever. Although I'm fairly sure of my assumptions here, if someone familiar with these saws could confirm it, I would appreciate it!

 

[silence dogood]

I'm watching this one. Just acquired a Miller-Knute (I think 3100). It needs lots of work.

 

[T. J.]

I reached out privately to a couple of H-M members who have the same saw (have I mentioned that this is an awesome forum?). One had an eccentric that measured 2.624". Mine measures 2.040 - 2.050". So, my plan going forward is to machine the yoke on the spring lever back to round. Then I'll build up the circumference of the eccentric by brazing and machine it to match the yoke.

Also, I'll be ordering some bronze bearing stock and machine it to replace the worn bushing. I asked a question regarding the machining of the bushing here that has generated some discussion. This project will be on hold for a week or so, but I'll post some more pics when I've made some progress.

 

[T. J.]

Progress on the saw has been a little slower than I'd like (as usual), but I'm getting there. I've got about half of the parts painted and they're looking good. Here's the base casting:

I also got the new crankshaft bushing made. I used 932 bearing bronze from McMaster. I started by making a stepped plug for tailstock support, since I don't have a bull nosed center. The steps were a slip fit for the as-cast ID and the finished ID.

Here's my setup in the lathe.

I cut the stock about an inch over finished length so I would have enough to chuck. I first turned journals for the steady rest and set it up. I then bored the ID, going about halfway, then swapped ends and repeated. When swapping ends, I switched to the 4 jaw chuck and placed a scrap piece of 1" rod inside the bore to prevent crushing the now-thin walled stock. After removing the steady rest and reinstalling the tailstock plug, I turned the OD and parted to length.

Here's the old bushing, new bushing, and the remaining raw stock.

 

[brino]

Beautiful job!

 

[TheCobbler]

Did you make a drawing on that bushing? I'm down to that bushing in my rebuild.

My push arm clevis and crankshaft were worn out, so I modified mine with a bearing.