MAK 127 Auto Focuser

[Mav359]

No real need i suppose but why not

Started to build an auto focuser for my MAK, the optics are great but you only need to look at the mount and the thing shakes all over the place so i figured if i can focus away from the scope then all the better. Its mainly for visual but i intend to a bit of planetary, solar  and moon pics with it. I'm going to get ant EQ5 for it i think

Nothing fancy Easy stepper and nano wired together, i have headed the boards and mounted it all in a project box... simples.  The only thing extra i do is wire the easy stepper up to a RJ11 port & one at the motor end, that way i can use a single cable from the motor down to the control box. Motor is here and the RJ11 port has been soldered to the motor cable. Control box done.

Awaiting the pulleys to arrive and then once they are mounted i can work out exactly where the motor box will sit and the pitch between the pulleys and can then order the belt.

Just a repeat essentially of what i did for my SCT.

[nightfisher]

Any progress on this project?

[Mav359]

Hi Jules

Been busy and waiting on parts but finally made progress today.

Ally plate arrived and ive cut it out & the pulleys are here.

Im using the visual back as part of the attachment mount, only thing is because of the plate it doesnt quite lock the visual back in place so an O' Ring is going to be required. Have measured the pitch between the Pulleys as 80mm so i can get the belts ordered now. As i said a variant on my SCT AF but i'm quite please, few screws here and there i need to replace and im going to put a velcro backing between the OTA and the back of the project box as another means of securing the housing in place.

They were the biggest and smallest pulleys i could use so the gear ratio is only 2.4:1 but its better then none at all. Once i map the movment of the motor i can work out the steps required and the speed at which to use the AF

appriciate any thoughts and comments

[Mav359]

Well it works but inevitably there is a small issue.... 3mm small in fact

The motor pulley and focuser came in with a pitch between them of 80mm, unfortunately the closest cross morse could get with the belt was 83mm so its slightly too big....... tut

Easy enough fix my ally plate was 180mm long so im going to re-order that and use the first attempt as my template for the Visual back & focuser cuts. The motor box will move to the end of the new bar pick up the 3mm and all will be well in my world :-)

As it is its perfectly useable it deffo can't come off, there is some very occasionaly slipage but its actually fine. I could leave but my OCD is kicking in and the statement "That Won't Do" keeps ringing in my ears

Couple of other things to do is to secure the motor box to the OTA but that will have to wait now until the new plate arrives and i can seat the box. The other thing is a few washers/o-rings to lock the visual back a bit more

Cheers

[nightfisher]

Looking very good, where did you get the ally plate, i need a piece to do my 150 mak focuser

[Mav359]

Looking very good, where did you get the ally plate, i need a piece to do my 150 mak focuser

Click Metal

http://www.clickmetal.co.uk/Angle-Types/Sheet-and-Plate/Aluminium-Sheet-1mm---5mm/p-16-6-22/?x=x&plateID=337&vp=25.48&vcpu=2.4&vcpo=0.8&vgrade=1050

Love this place