After a few days off in my shop I decided it was time to tackle the crankshaft for my Upshur Farm engine. I decided I would machine it out of 1018 steel as one piece as described in the plans. I milled it to size, marked out the offset centers and rigged up a between center setup on my Taig. I grind up some hss tools according to an article in Model Engine Builder. On my little Taig, machining steel this size is a slow and tedious process. I figure I put in about 1 to 2 hours a day for about a week in my spare time to just machine the main journal. Here's a picture of my nice shiny finished journal:
Very satisfied my result, I proceed to unmount the part so I can saw off the excess material so I can turn the crankshaft ends on the 1/2" off set center. I mount the part in my vise and cut down the middle first on both sides of the journal. Cutting 1/2" steel with a hacksaw is cruel and unusual punishment but lacking a bandsaw, the only alternative.
After about half hour of intermittent cutting, I finish the longitudinal cuts. All I have left are two 1/2" cuts across the part. I remount the part in my vise and cut away. Have you guessed yet what I did? First the picture:
Pretty nice huh? A 0" THROW CRANK!!!!!!!!!
Needless to say it's hard to convey what I felt at the moment. After considerable expletives in English and Spanish I had to walk away from my shop. It was only yesterday after 4 days that I was able to get back in the shop. There's no way I'm going through the ordeal again of machining a one piece crank on my small equipment. After looking at it for a while, I decided to try to salvage some of it by combining the machined journal/web with a pinned and soft soldered shaft. Here's where I'm at:
Looks like it's going to work. I'll have to make a few spacers as the main journal/web assembly is about .10" too narrow but that should not be a problem. I'll continue updating soon. What was that saying, "Measure twice cut once?" Lesson learned!!!!
Jenaro
Very satisfied my result, I proceed to unmount the part so I can saw off the excess material so I can turn the crankshaft ends on the 1/2" off set center. I mount the part in my vise and cut down the middle first on both sides of the journal. Cutting 1/2" steel with a hacksaw is cruel and unusual punishment but lacking a bandsaw, the only alternative.
After about half hour of intermittent cutting, I finish the longitudinal cuts. All I have left are two 1/2" cuts across the part. I remount the part in my vise and cut away. Have you guessed yet what I did? First the picture:
Pretty nice huh? A 0" THROW CRANK!!!!!!!!!
Needless to say it's hard to convey what I felt at the moment. After considerable expletives in English and Spanish I had to walk away from my shop. It was only yesterday after 4 days that I was able to get back in the shop. There's no way I'm going through the ordeal again of machining a one piece crank on my small equipment. After looking at it for a while, I decided to try to salvage some of it by combining the machined journal/web with a pinned and soft soldered shaft. Here's where I'm at:
Looks like it's going to work. I'll have to make a few spacers as the main journal/web assembly is about .10" too narrow but that should not be a problem. I'll continue updating soon. What was that saying, "Measure twice cut once?" Lesson learned!!!!
Jenaro