Fine focus knobs for 102 mak.

[dave34]

Ive come across fine focus knobs to fit over the original knobs on SCT 8" AND 9.25"  scopes on ebay, i'm wondering whether they would be suitable for my  Sky-Watcher 102 Mak , rather than the clothes peg trick, can anyone confirm whether the knob size is the same.   Many Thanks, Dave. 

Edited June 29, 2022 by dave34

[DavieH]

Hi dave34, I've been looking at those too - I reckon they would be fairly easy to modify it they weren't a perfect for for your 102 Mak. Only thing putting me off is the postage from the U.S. - it's more than the knob!! Have you come across any being sold in the UK?

[dave34]

Hi DavieH, ive ordered a glow in the dark knob from here in the UK, only £8 with free p&p, made for 127 maks, the seller has said i could return the item if it doesnt fit, the OD may be too large, but i think it will be easy to shave the OD down a bit to fit the 102.   

[DavieH]

Hi dave34,

That sounds good - do you mind me asking where you found it?

[SthBohemia]

On 29/06/2022 at 10:41, dave34 said:

rather than the clothes peg trick

I'm curious! The clothes peg trick!! Wassat??

[Zermelo]

The push-on knob for the 127 is available in the UK here:

https://www.ebay.co.uk/itm/185060378222

I couldn't say if the 102 and 127 have the same size focuser knob.

The alternative is a clothes peg on the focuser knob, move the end with a finger and it's more sensitive than twisting the knob directly.

Edited July 8, 2022 by Zermelo

[dave34]

8 minutes ago, Zermelo said:

The push-on knob for the 127 is available in the UK here:

https://www.ebay.co.uk/itm/185060378222

I couldn't say if the 102 and 127 have the same size focuser knob.

The alternative is a clothes peg on the focuser knob, move the end with a finger and it's more sensitive than twisting the knob directly.

i bought the knob in the link above, unfortunately  it doesnt fit the 102, the OD is too big, not enough room between the knob and the visual back. 

[SthBohemia]

I would be more inclined to fabricate something using a Meccano 3" diameter pulley with rubber tyre attached on a 1" axle fitted into a bored out focus knob and clamped with a set screw to the 1" axle. All thats required being to bore 2 holes and tap the knob for the set screw.