HD-1501MG modification problems

[Hernan]

I finally got around to getting myself an arduino and servo.
I thought i should get a good quality, high torque servo so i could build my robot up to something sizeable (eventually i want it to carry a netbook). however, i may have gone too far, as the servo seems too good quality for me to hack.
The little pin on the drive gear seems to be firmly stuck in the gear, and will not budge. The only thing i can think of is to try and saw it out, but im afraid of damaging the gear in the process (the pin is rather thick, and fairly solid metal). Has anybody hacked this servo before? or have a trick for getting pins out? Or will i need to either spend a fair amount of time very carefully sawing and then filing this pin, or a little money buying another servo which is either easier to hack or already continuous.
Getting the pot sorted wont be a problem, theres a small piece of plastic between the drive gear and the pot which can be removed. It doesnt seem to even need to be glued, as theres now a bearing between the drive gear and pot.
theres some pics of the servo here: http://www.robotgear.com.au/Product.aspx/Details/421, in which you can make out the troublesome pin

[Soeren]

Hi,

If you have just the gear wheel (and nothing else) out, you could hold the steel pin with strong pliers, heat up the brass around the pin (brass expands more than steel) and holding the brass gear with another pair of pliers, pull the steel pin out by twisting/rotating it while still heating the area.
With a strong pair of pliers, you may be able to twist it out even without heat (put a little outwards pressure on the twisting motion).

Alternatively, a Dremel or similar rotary tool with a cutting disk will easily cut the pin close to the brass and a grinding stone bit can be used to make it level with the brass.
Hand tools won't quite do, if the steel pin is hardened.

Whichever way you do it, clean it carefully with benzene or a similar solvent and reapply grease before reassembly.


Before you do anything non-reversible, you might wanna contact the dealer, to see if you can get a spare gear, in case you either screw it up or just want to restore it's original function at a later date.

[Hernan]

Cheers, I'll give that a shot.