Hey guys: I’m installing a simple Atlas Motor Drive to my turn table and am having some difficulties. When the motor runs, the drive worm does not want to turn the gear. It just spins within the teeth and refuses to “catch”. The instructions state to make certain that the worm is not jammed tightly against the gear because a small amount of clearance is necessary. It is not. The unit also is not against the manual crank shaft. The tt itself turns and indexes perfectly when turned manually with the crank. It is almost as if there is too much open space between gear teeth allowing the worm to just spin freely. Any ideas? Thanks folks…
I’m not sure what you mean by “spins within the teeth.” Are the worm gear and the flat gear wheel engaged?
If they are assembled right, does the worm gear actually spin, but not move the flat gear? If that’s the case, check to see that the worm gear is solidly mounted to the shaft. It may be slipping.
The worm gear and the flat gear are engaged it seems properly. The worm gear spins fine but won’t move the flat gear. It is also solidly mounted to the shaft with no slippage. Very strange as this seems like a very simple contraption!
Yes sir…the worm spins continuously, doesn’t bind but does not “catch” anything. As it spins, the ridges of the worm gear go round and round within the same spots between the teeth of the flat gear. continues spinning without moving the gear. And yes the hand crank is off. One of the darndest things I’ve come across. I can take the motor off and turn all 3 of the flat gears by hand no problemo. Tried the motor without the gear cover on to see if I could spot anything unusual in there to know avail. Also flipped the flat gear upside down to see if it could catch the spinning worm gear that way also with no luck.
As I recall, you have to snap off some part of one of the housings to slide the drive unit in. If you didn’t remove enough, then the drive unit will not go in far enough, and will fail to fully engage the gear. Or, there’s some other obstruction keeping the drive from seating properly.
If it’s not that, then the shaft mounts for the worm gear axle may be broken, or the axle isn’t seated properly.
Thanks for your thoughts Mr. B! I know the worm gear axle isn’t broken but I’ll check the part about the snap-off housing. I know that it didn’t give a clean break when I took it off and I’ll check that theory tomorrow morning. Sorry I didn’t get back to this but that darn thing called a job keeps getting in the way of more important things like turntables![:D]
OK. I re-installed the motor again this morning. Turned power on and got the same result as before. Turned the power off and attempted to turn the worm gear with my fingers to see if I could feel anything binding or stuck. Lo and behold as I turned the worm gear by hand, the flat gear began to move as did the track! Then a light bulb went off in my head. The worm gear had been spinning waaay too fast to even begin to think about “catching”. Here’s where I realized that I had accidentally hooked up the motor to the AC terminals on the power pack! Switched to DC where I could regulate the speed of the motor and it now works totally fine! [:I] After I unbury my head out the sand I will head back down to the layout and run the permanent wires for the darn thing. It’s frustrating that I wasted a whole day of layout building for something as silly as that, but hey, that’s the nature of the beast! [(-D] Thanks Mr. B for your assistance! To paraphrase Sherlock Holmes, once you eliminate all possibilities except one, that is the answer!
My recollection is that AC is the correct installation. I used a ‘junk’ toy power pack and adjusted the throttle to a realistic speed. The only time there is any hesitation is when I throw a turnout switch. Check the installation instructions.
It has been a while since I installed it, and the memory isn’t getting any better as time goes by. sigh
edit: OK, I googled and now I remember. DC is correct. The switch throwing consumes AC which sucks power from the DC. Should’ve clicked with the throttle comment in the first paragraph. Which proves the second paragraph. Sorry. [banghead]