Re: Union Pacific Big Boy 4012 in 1.5"
Posted: Wed Jun 07, 2017 4:51 am
Asteamhead, thank you! By the way a pizza oven is a great idea! I'll have to get one specifically for doing the rest of the rims.
These last few weeks I decided to tackle one of the more repetitive tasks and get it out of the way. Springs.
After a lot of investigation I decided to cut them with an abrasive wheel and drill the holes. I considered punching and cropping but considering the time to make and/or source the tools I would have them done faster if I cut and drilled.
Using the angle grinder with a ultra thin cut off disc kept heat to a minimum and when the disc showed signs of glazing I swapped a fresh one on. I cut all the leaves about 0.5mm longer to allow for cleaning up and squaring off with a quick pass of a with a carbide end mill. The leaves were then dropped into aluminium drilling jigs I made and stack drilled with straight flute carbide drills. The clamps were made from box section and the rollers are 0.375" rod that was drilled in the lathe. I did deviate from the drawings however, which called for a 0.125" pin to pass through the roller and be riveted over at either end. I simply used an M4 button head cap screw and tapped one side of the clamp, any excess head height that causes interference will be ground down. It has the bonus of making spring packs more easily serviceable should they need attention for whatever reason.
As of now 2 engine truck, 10 main and 4 trailing truck springs are done. Just another 14 for the tender and the monotony is over!
These last few weeks I decided to tackle one of the more repetitive tasks and get it out of the way. Springs.
After a lot of investigation I decided to cut them with an abrasive wheel and drill the holes. I considered punching and cropping but considering the time to make and/or source the tools I would have them done faster if I cut and drilled.
Using the angle grinder with a ultra thin cut off disc kept heat to a minimum and when the disc showed signs of glazing I swapped a fresh one on. I cut all the leaves about 0.5mm longer to allow for cleaning up and squaring off with a quick pass of a with a carbide end mill. The leaves were then dropped into aluminium drilling jigs I made and stack drilled with straight flute carbide drills. The clamps were made from box section and the rollers are 0.375" rod that was drilled in the lathe. I did deviate from the drawings however, which called for a 0.125" pin to pass through the roller and be riveted over at either end. I simply used an M4 button head cap screw and tapped one side of the clamp, any excess head height that causes interference will be ground down. It has the bonus of making spring packs more easily serviceable should they need attention for whatever reason.
As of now 2 engine truck, 10 main and 4 trailing truck springs are done. Just another 14 for the tender and the monotony is over!