Which motor do i need for DIY focuser?

[bcfcciderhead]

If i was to make a DIY auto focuser what type of motor would i need?

I guess a reversible type to be able to focus in/out, one which dont spin to fast and about 9v?

I feel confident enough to put together all the bits to make it work but unsure about motor types.

Cheers

[Bizibilder]

Do you want to computer control it or just an electric focusser with a hand switch?

[faulksy]

you only have to change polaraty to change direction on a dc motor so thats easy. probably need a gearbox with some thing like a 2.1 reduction so it can be slow and have some torque. you can get all these at maplins

[bcfcciderhead]

Thanks for the quick reply's guys, be happy enough with just an electric focuser via a hand controller, got enough USB things plugged in as it is.

I dont think i have thought this through proper after reading up on this, i was just hoping to fix a small motor that turns at a slowish speed in both directions all by a little switch

Lego motor came to mind.......maybe i just might go i buy the Skywatcher auto focuser, cant see me saving a lot if i try and make one

[Bizibilder]

Nah!! Two servo's and a bit o' wire - works a treat!! http://homepage.ntlw...tricFocuser.htm Made one myself a while ago. The slave servo is driven at whatever speed you turn the master servo.

Or you can do it the "posh" way, again using a servo and battery box: http://stargazerslou...e__hl__focusser I have now made several of these, one for each scope - I just plug the power supply into the one I'm using.

[faulksy]

Nah!! Two servo's and a bit o' wire - works a treat!! http://homepage.ntlw...tricFocuser.htm Made one myself a while ago. The slave servo is driven at whatever speed you turn the master servo.

Or you can do it the "posh" way, again using a servo and battery box: http://stargazerslou...e__hl__focusser I have now made several of these, one for each scope - I just plug the power supply into the one I'm using.

thats good makes sence as the emf will drive it.like it a lot (said in a jim carey voice)