daedalusminos
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Easy to model...
- Thread starter ajlelectronics
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Rotator also sold by radio shack and others, I think this might be the one
www.thingiverse.com
Radio Shack Antenna Rotator Drive Gear by gjkozy
This is for the Radio Shack/Archer antenna rotator gear that was a design flaw through use of poor materials.
www.thingiverse.com
ajlelectronics
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Rotator also sold by radio shack and others, I think this might be the one
Radio Shack Antenna Rotator Drive Gear by gjkozy
This is for the Radio Shack/Archer antenna rotator gear that was a design flaw through use of poor materials.
Thank you for that. I looked but found nothing similar. I am going to print it now and compare it.
ajlelectronics
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How did you do it and in what package please?
daedalusminos
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Fusion 360 using the spur gear add in
If you want a resin printed verson done just shout
Pete.
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If the big gear was 0.5mm bigger it would be 60DP, so cutting/printing it at 60DP would be fine. The smaller one is more tricky because of the low tooth count and the shape it looks like it's been profile shifted. I see that the small one on the broken gear mates with another large gear. Remove that other gear and tell me the tooth count and diameter please then I will know the pitch.
Agroshield
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The centre distance between the mating gears might also help you and is easier to measure with confidence.
Determining the correct OD of a gear with an odd number of teeth is less easy than for one with an even number of teeth.
daedalusminos
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I'd assumed 0.4Mod (64dp) as the most likely candidate though that implies some measurement error,
Agroshield
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It might be possible to take some clues as to whether it is DP or MOD from the language in which the other dimensions of the product are produced. Someone said above that it was made for RadioShack, which is US and implies imperial. If there are threaded fasteners on it somewhere, they can be a helpful pointer. It sure is not made in US, but if it is designed in US for overseas manufacture, the drawings, including gears, are likely to be imperial.
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It is an interesting thread as the initial thought of 3D scanning, while giving a perfect digital representation of the part, is not at all helpful in the practical engineering task of making a replacement. Having the 3D model does not widen your choice for manufacture, but severely constrains it to additive machining processes such as 3D printing. It is the difference between a series of points such as (0,0), (1,1), (2,4), (3,9) and knowledge of the relationship y=x^2 .
ajlelectronics
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Now I am seeing just how ignorant I am of such things. It looks like a different language that I will have to brush up on, as so far I don't understand a word of it. I went to a decent Technical school where there was still a machine shop, but don't recall ever being taught about such things. Or would it have been a Mathematics lesson? If so, I have to admit that I was far from a star pupil, managing just a CSE grade 4.
I didn't pass Biology either, despite all the time I spent revising Human anatomy with students of the girl's school adjacent to ours.
I didn't pass Biology either, despite all the time I spent revising Human anatomy with students of the girl's school adjacent to ours.
ajlelectronics
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Rotator also sold by radio shack and others, I think this might be the one
Radio Shack Antenna Rotator Drive Gear by gjkozy
This is for the Radio Shack/Archer antenna rotator gear that was a design flaw through use of poor materials.
Two versions on there which appear to be the same. They are both too small however at 32mm and the spindle hole is also too tight. Scaling it up to 34.5 mm seems to allow it to drop in, but as it was gone midnight, I had little time to play further.
ajlelectronics
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Just for interest, I counted the remaining teeth and interpolated the missing ones and came up with 83. I will strip it further later today though.
ajlelectronics
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The same animal was available under a number of names, all with the same motor unit. I think this one was a Channel Master brand. It relies upon the gear train in the motor and controller running at the same speed to synchronise them. You do that by running the controller to one end stop and letting the motor run until it stalls, then go to the other end stop and do it again.
All fasteners so far are self tappers!
The only second hand controller that I managed to find was a Hirschmann which is an exception to the rule, running faster than the motor unit.
