New focuser

[Benno18 (Ben)]

Hi guys. Have bought a micro focuser from the ice trades, thinking that it would fit on to my sw 10 inch dob.
But it dosnt it's a bintel focuser

Was thinking of just making a mounting plate out of some sheet metal I have lying around, and then mounting the focuser to that.

Any objections???

Thanks in advance
Benno

[brian nordstrom (As avatar)]

That should not be a problem if you are careful in mounting the focuser in exactly the same place as the origonal , but before you do anything check that the two focosers have the same travel , in and out and are the same hight , if not you may have trouble reaching focus .
If they are the same ( within 10mm or so ) it wont hurt .
Brian.

[Benno18 (Ben)]

yeah checked that brian. They look quite close.
If it needs to travel out a bit more would you think an extra plate would be sufficient?

thanks
benno

[erick (Eric)]

What doesn't fit, Ben? The Bintel focussers usually come off the baseplate (couple of sunken hex grub screws). If you can get the right baseplate - always worth asking in the classifieds - you might just be able to swap it over.

[Benno18 (Ben)]

The mounting holes of the new focuser dont line up with the old mount holes on the scope tube. The focuser is too small

yeah that would be great Erick. good thinking Batman!!

[ZeroID (Brent)]

Drill new holes or make an adapter plate, no problem. Just do it !!

I LOVE my workshop !!

[brian nordstrom (As avatar)]

Thats it , drill new holes , but use this sequence ,
1st place the tube horizontal then place the new focuser as close to center as you can and mark 1 hole , remove the focuser and drill this 1st hole , then bolt the focuser not to tight with this 1 bolt , this allows a little movement , then mark the 2nd hole diagonally across from the 1st hole , using the with the drill bit as a scribe and remove the focuser .
Drill the 2nd hole and bolt the focuser with these 2 fairly tight ( if the hole aint quite alligned drill thru the focuser into the hole to centralise that hole , then bolt it down with 2 bolts ).
Then just drill the 3rd and 4th thru the focuser body and this garentees all holes are in the right place , remove the focuser for the last time and clean the sharp edges , remove any swarf ( bits of drilling ) and bolt the focuser in place for the last time , done ! .
Just be sure to do all this with the tube horizontal so you dont drop any swarf or tools onto the main mirror .
Easy as that .
Any chance of a few photos ? or an update when you have finished ?
Brian.

Originally Posted by ZeroID

Drill new holes or make an adapter plate, no problem. Just do it !!

I LOVE my workshop !!

[brian nordstrom (As avatar)]

I forgot to mention its easier with 2 people doing this .
Brian.

[Benno18 (Ben)]

yeah brian photos will be on the way. Will be doing it tomorrow morning............. fingers crossed!!!!!

Should be quite easy, juat wanted to make sure i was doing the right thing!!!

cheers guys
Benno

[Benno18 (Ben)]

Just wanted to show those interested this photo.
It is the plate connected to the scope. Now to just attach the focuser!!!!!!

Should i just use the eyeball to align, or something special like a collimator?

cheers
Benno

[brian nordstrom (As avatar)]

Spot on Benno , a good eyeball line up will be ok as there is plenty of movement in the spider and secondary to compensate a small ( 2mm or so ) missalignment .
Look forward to the finished photos .
Oh yea , aint it fun tinkering with scopes ? just be very careful around the optics .
Brian.

[ZeroID (Brent)]

You're onto it Ben. I shifted my focal distance in to accommodate the DSLR and it loused up some EPS but I just got an extender that threads on and bingo we're back in business.
There is always a way ...