metric drawings imperial workshop

Martin - as well as the EN8 steel bevels that Jason has linked to above, HPC also do the bevels that you are after in Delrin link at much better prices £20 + vat for the pair. EN8 is somewhat overkill in your application, the drawing suggests brass (CuZn) in the materials spec with mild steel as an alternative. Given the application and likely speed that you'd be using I'd think that the Delrin gears would be adequate. If they broke down eventually then they have the advantage of being standard parts that could be replaced or up graded quite easily.

Brass bevel sets in 3:1 ratio used to be very common as they were used in the final drive for slot cars, but I don't know what module or dp they were. They were also fairly cheap from memory, they might still be around, a bit of "Googling" could bring them to light. Could also be worth asking at your local model shop to see if any of the RC helicopters, cars or trucks use a suitable gear set. If so they are very probably available as fairly cost efective spare parts.

Just found moulded delrin bevels for your application at Motionco price even better - cheap enough to buy on an experimental basis

Edited By Keith Long on 23/10/2014 14:55:50

Just had a look through teh PDF, quite an interesting project and a novel method of propulsion, have I got it right that as the blade rotates the pitch varies and that is what gives the directional thrust?

HPC have them but make sure you are sitting down before clicking here

Martin - as well as the EN8 steel bevels that Jason has linked to above, HPC also do the bevels that you are after in Delrin link at much better prices £20 + vat for the pair. EN8 is somewhat overkill in your application, the drawing suggests brass (CuZn) in the materials spec with mild steel as an alternative. Given the application and likely speed that you'd be using I'd think that the Delrin gears would be adequate. If they broke down eventually then they have the advantage of being standard parts that could be replaced or up graded quite easily.

Thanks Keith for that my secondary education was not as good as I would have liked and if you had not pointed that out I was going to have a go at making them in common salt but realised that NaCl

Does the Voith website still have the great simulator? If I remember right, there was a really spiffy animation of the system that showed you how you steered the boat by using a joystick. I don't know much about shipping, but I do know that the double-ended Halifax to Dartmouth ferries here in Nova Scotia have Voith-Schneider propulsion. They can sail in any direction, including sideways. When they reach the dock , they keep the props turning to force the boat against the side and end of the dock. That way they never have to tie them up and the turn around time is just a couple of minutes.

way, way off topic for this thread, by my plan a few years back was to see if the VS system could be applied to a vertical-axis wind turbine. I drew up a complete 12" = 1 foot prototype on AutoCAD but never got the chance to make it.