I apologize for the lengthy post (and if this post is in the wrong section!). I recently received two of Adafruit's "Micro servos" (the SG92Rs) along with Adafruit's Pan/Tilt kit. I'll admit I'm a bit disappointed. I followed the assembly instructions and setup a simple test sketch to try out the servos once installed in the kit. As soon as either were powered up (when set to 1500us) they both proceeded to slam hard against their endstops. Thinking this was an issue with my code I went back and attempted to trim the servos. Nothing worked. After a few more attempts both servo's endstops broke and the servos spun freely. What a bummer.
After disassembling one of the servos, to see what was going on, I think I found the culprit. The flanged screws included with the servos are far too long. When they "bottom out" with about a 1/8th to 1/16th of an inch left before they properly engage with the servo horn. Thinking this was "by design" I continued to screw the screws in until well seated. This worked but also damaged the servo. It dislodged the press-fit connection between the serovo's potentiometer's shaft and the output drive gear, effectively creating a "continuous rotation servo". After re-reading the assembly guide there was no call-out for this and I'm not sure how I would have known not to use the provided screws. If I were to do it again I would "snip" the screws to about 1/2 their current length.
Anyway, I wanted to let Adafruit know of the potential defect and see if there was any way I could get replacement servos. Additionally, I would suggest a fairly large warning to be put on the instructions that the screws provided in the servo bag are TOO LONG and should be altered before installation. If Adafruit is agreeable to the replacements I would also like to purchase another kit. Upon assembly of the first kit I stripped several screws and doubt they would go back easily upon a second assembly.
Issue with Micro Servos & Pan/Tilt Kit. Assembly damages ser
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Please be positive and constructive with your questions and comments.
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- adafruit_support_bill
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Re: Issue with Micro Servos & Pan/Tilt Kit. Assembly damages
The screws included in the full-kit are different from the ones packed with the servos when purchased separately. The SG92R comes with 2 washer-head mounting screws. The single short screw is for the horn attachment.
If you contact [email protected] with a link to this thread, we can replace the servos.
I'll add an extra warning to the assembly guide.
If you contact [email protected] with a link to this thread, we can replace the servos.
I'll add an extra warning to the assembly guide.
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- Joined: Fri Nov 23, 2012 9:03 pm
Re: Issue with Micro Servos & Pan/Tilt Kit. Assembly damages
Thanks Bill!
Just a note, I don't think my kit came with washer-head screws. The only ones I saw where the ones that came with the servos. Hence this picture (https://learn.adafruit.com/assets/26885) confused me :/
Edit - Alright. I re-read your post and I understand. I would suggest perhaps a call out whenever there are differences between the kit with servos and the kit without servos.
Just a note, I don't think my kit came with washer-head screws. The only ones I saw where the ones that came with the servos. Hence this picture (https://learn.adafruit.com/assets/26885) confused me :/
Edit - Alright. I re-read your post and I understand. I would suggest perhaps a call out whenever there are differences between the kit with servos and the kit without servos.
Please be positive and constructive with your questions and comments.