Yeah a straight rod, while simpler to build mechanically, adds a lot of complications to driving the build - like you say John P, drive speed is dependant on how far up the rod the top platform would be etc. The design I am opting for is much simpler in the long run and less error prone.
Ok I will go with a 1:1 ratio for the external gearing then (assuming I can get the necessary hardware and engineer it to purpose, but 1:1 should give me the best chance of doing so), meaning I will need the motor to run at exactly 64rpm for a shaft speed of 1rpm. Nice and simple... in theory
Good to know the heat sink set-up looks sound. Actually I meant to say that the amount of goop you get in the kit is really a tiny amount - I know you only need a little but I was really scraping the last of it up, and ended up rubbing the little pack it comes in over some of the surfaces to salvage every last bit. Not sure if I got an unusually small amount with mine.
I think I want to buy some more to top it up, as it is certainly not enough to form a small bead around the washers like in the build instructions. What sort of stuff can I use, is it the same thermal paste you buy for CPU application?
Ok I'll test the transistors are not connected to the heat sink tonight - so to do this ( newb instruction time ) I put one probe on the heat sink, and one on the metal part of one of the transistors, turn the MM to the lowest ohm setting (I dont think it has a beep setting) and if it is all good the it should read infinity?
Cheers
UPDATE: I just got around to testing for shorts, and all is good, no shorts on any of the transistors to the heat sink buffer plate. I also did the rest of the shorts tests on the build instructions (C3 and C1 caps) and they are sound too.
Ok I will go with a 1:1 ratio for the external gearing then (assuming I can get the necessary hardware and engineer it to purpose, but 1:1 should give me the best chance of doing so), meaning I will need the motor to run at exactly 64rpm for a shaft speed of 1rpm. Nice and simple... in theory
Good to know the heat sink set-up looks sound. Actually I meant to say that the amount of goop you get in the kit is really a tiny amount - I know you only need a little but I was really scraping the last of it up, and ended up rubbing the little pack it comes in over some of the surfaces to salvage every last bit. Not sure if I got an unusually small amount with mine.
I think I want to buy some more to top it up, as it is certainly not enough to form a small bead around the washers like in the build instructions. What sort of stuff can I use, is it the same thermal paste you buy for CPU application?
Ok I'll test the transistors are not connected to the heat sink tonight - so to do this ( newb instruction time ) I put one probe on the heat sink, and one on the metal part of one of the transistors, turn the MM to the lowest ohm setting (I dont think it has a beep setting) and if it is all good the it should read infinity?
Cheers
UPDATE: I just got around to testing for shorts, and all is good, no shorts on any of the transistors to the heat sink buffer plate. I also did the rest of the shorts tests on the build instructions (C3 and C1 caps) and they are sound too.
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