Recumbent - Machining a stem?

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




View Full Version : Machining a stem?


BlazingPedals
02-04-08, 10:33 AM
Let's see if there's any machinists in the house.

I'm building a new steering system for my Baron. I would like it to consist of a Terracycles Flex-Stem, flipped backwards, and a RANS LWB riser. I will add a stop to the Flex-Stem, so that's not an issue yet. The problem is the RANS riser.

The riser is listed in Hostelshoppe as 1 1/8" OD, 1" ID. If that were true, it would fit right over the 1" extension of the Flex-Stem. It does not. The 1" figure is merely a nominal number, and actually measures 15/16", so if I want to use it I need to remove some material along the inside diameter, for about 3" into the riser. Any ideas on how I would do that? Using emery cloth sounds like way too much work and not very accurate either. I've got access to common hand power tools and a drill press, but no fancy shop equipment.


Dr.Deltron
02-04-08, 11:26 AM
I've got access to common hand power tools and a drill press, but no fancy shop equipment.

I would say that because you are trying to make a 15/16" hole into 1", I would use the drill press and a hole saw bit that's 1". The saw kerf should be just about right to remove that extra 1/16" diameter.

PaPa
02-04-08, 07:34 PM
Use an automotive brake cylinder hone at low RPMs w/plenty of coolant. Dry cutting and/or too fast of cutting speed will only clog-up the stones.


BlazingPedals
02-04-08, 08:05 PM
I am trying the brake cylinder hone. So far I did it dry, but haven't been clogging up the stone. Not enough heat that I can't hold the part in my hand while I'm grinding. That 6061 is hard stuff! Anyway, it's almost bored out enough; I'll have to work more on it tomorrow. I was using a cordless drill and I managed to run the battery down.