I recently purchased an ZWO EAF electronic focuser as my existing JMI moto focuser for GSO newts are no longer available, so getting in first before it fails
I googled the ZWO website to work out how I could install it and they said that this focuser doesn’t support GSO crayford dual speed focusers for newts. I joggled through all their photo examples folk have posted and there was nothing that resembled a GSO newt with dual speed focuser
I thought oh well I rig up a solution to make it work then
Materials
90mm stainless steel hose clamp
Roll of black pvc tape
30 x 50 x 2 aluminium extrusion
Screws
Misc
Took me 45 minutes and works like a treat
Better still I didn’t even have to drill the OTA or existing focuser , so I if I wanted to I can sell the OTA in the future without holes , scratches etc..
Photos show it fitted to my 6” newt in Sydney but I will be taking the EAF down the coast to my NexDome and fitting it to my 8” newt. It only takes 5 mins to fit
Photos attached
Maybe this set up may help others wanting to fit an EAF to a GSO newt with a crayford dual speed focuser
Hose clamps are on the same level as WD40 and duct tape
I agree , but in this instance , the EAF is supported rock solid , no holes in the OTA , looks neat and tidy and easy to remove and re install.
There’s no mounting facility on the GSO Crayford dual speed focuser to support the EAF bracket ( it only has one fixing point , a 4mm screw point )
To mount it off the OTA, IMO would look like a dogs breakfast with a big off set bracket etc....
At the end of the day it works and works well !!
Thanks for your positive comment
By cutting down the supplied bracket, the EAF can be quite neatly be mounted onto the OTA. Yes it’s a tight fit but once mounted looks like it belongs there. Yes it means drilling the OTA but it’s by far not the only modification I’ve done on it. I might have been less keen if it was a Planewave or something.
By cutting down the supplied bracket, the EAF can be quite neatly be mounted onto the OTA. Yes it’s a tight fit but once mounted looks like it belongs there. Yes it means drilling the OTA but it’s by far not the only modification I’ve done on it. I might have been less keen if it was a Planewave or something.
Cheers
Ryan
Thanks for photo Ryan a very neat job, I decided I didn’t want to drill the OTA, so the hose clamp solved the issue and doesn’t block any adjustments on the OTA or focuser. If I painted the hose clamp semi gloss black you wouldn’t know it’s there !
Thanks for responding
Cheers
Martin
Thanks for posting this thread Martin. I like your idea a whole lot better than forking out another couple of hundred to buy and post the TS item.
I assume that the lock nut on the underside of the focuser becomes redundant so you can leave it slacked off and let the focus motor be the brake. I assume you still set some tension on the other screw though. Is that how it works?
Peter,
Are you referring to the 2 top and bottom chrome thumb screws located on the rear mid section of the focuser ( the top one is a tensioner which allows heavier eye pieces or heavier cameras to stop slipping down whilst rotating focuser and the other is a clutch to hold the focuser stationary irrespective of rotating the focuser knobs.
If so, the top chrome grub screw I tighten as necessary to stop my heavy ZWOASI2600MC from slipping down and the bottom I leave loose.
The EAF focuser essentially just replaces your fingers rotating the focuser knob
Attached are my notes on setting up the EAF focuser to my GSO 6” and 8” newts plus some more pics of my 8” newt set up
NB: The most difficult part of the whole set up is drilling out or enlarging the existing EAF alloy coupling hole to fit on your focuser shaft . It must be done carefully and horizontal with the correct size drill bit ( I think 4.5mm ) otherwise if the hole is to big the opposing grub on the coupling won’t tighten up enough and you will get slippage and if it’s not drilled accurately ( or on a bad angle ) the coupling could snap under gimbal rotation.I wrapped two turns of pvc tape around the coupling and used my small bench vice. My wife helped me to line up the drill NSEW. You only drill into the coupling just shy of half way too. Apart from that , the rest is fairly straightforward
Good luck
My EAF focusers on both rigs have been working perfectly.
Martin, the idea of using a hose clamp is excellent. For years, I have been using these clamps (bought for almost nothing at Bunnings) for so many purposes other than, well, clamping a hose. But I would have never thought of using one to stabilize an electronic focuser! I don’t intend to buy one for the foreseeable future, as I would like to crawl before I can run, but just knowing that there are easy installment possibilities without drilling is great. Thanks for sharing your procedures.
By the way, my rig is finally complete - except for the Optolong L-Extreme filter arriving in a couple of weeks. Guide cam & scope are set up piggy-backed on the BT200 and PHD2 profile set up thanks to the instructions you sent me. Today I will collimate and wait for what feels like an eternity for good weather.
Martin, the idea of using a hose clamp is excellent. For years, I have been using these clamps (bought for almost nothing at Bunnings) for so many purposes other than, well, clamping a hose. But I would have never thought of using one to stabilize an electronic focuser! I don’t intend to buy one for the foreseeable future, as I would like to crawl before I can run, but just knowing that there are easy installment possibilities without drilling is great. Thanks for sharing your procedures.
By the way, my rig is finally complete - except for the Optolong L-Extreme filter arriving in a couple of weeks. Guide cam & scope are set up piggy-backed on the BT200 and PHD2 profile set up thanks to the instructions you sent me. Today I will collimate and wait for what feels like an eternity for good weather.
Thanks,
Stéphane
Stephane,
Thanks, at least some folk think it’s a good idea. Unless you notice the clamp screw behind the base of the focuser , you would think it’s a purpose fit accessory
I did post it on the ZWO forum and sent it to Bintel as well.
That’s great your rig is almost set up. My advice from now on is take your time , step by step, you will most probably have a few set backs but all part of the process
The weather hasn’t been kind to all of us over the last few months but it will eventually improve
Whilst the weather is bad go through your procedures, collimate your scope , balance your rig with all gear on board including camera etc.. and mark positions of the counterweights and scope with texta pen , maybe do some simulations , learn your software programs , there’s plenty of things to do and check before we all get some clear nights
Good luck and be patient
Cheers
Martin
Thanks for your careful guidance. Purely by luck, I already have a 5 x 4.5 mm flexible coupling so I will be spared that part of the process. I find I have a box full of various sizes of couplings left over from days long ago when I was messing about with DIY Arduino focuser control projects.
I am still waiting for Bintel to get my ZWO EAF into stock. It’s been a slow process.
Thanks for your careful guidance. Purely by luck, I already have a 5 x 4.5 mm flexible coupling so I will be spared that part of the process. I find I have a box full of various sizes of couplings left over from days long ago when I was messing about with DIY Arduino focuser control projects.
I am still waiting for Bintel to get my ZWO EAF into stock. It’s been a slow process.
Glad to help
Waiting for Astro gear in the last 18months has been painfully slow , but as long as when you receive it , it’s the correct item and in good condition with nothing missing , that’s the main objective
I waited nearly 9 months for my NexDome to arrive from Canada, everything was spot on when I eventually received it.Imagine if a panel was missing , I’d be still waiting 6 months or longer to finish building it
Its a bit Late but I just picked up a GSO 6" F/4 ota and had the same problem when i went to attach my Gemini focuser, it uses the same bracket as the ZWO EAF.
I was going to make something similar to Martin made, then found someone had already come up with a 3d printed solution, so if you have access to a printer this worked great for me https://www.thingiverse.com/thing:4946220
just used a m4x16mm bolt in the locking hole, another m4x16mm in the capitive hole for the bracket, 2 m3x8mm holes to secure the bracket to the 3d part and a m4x25mm or 30mm bolt to tension the focuser
Its a bit Late but I just picked up a GSO 6" F/4 ota and had the same problem when i went to attach my Gemini focuser, it uses the same bracket as the ZWO EAF.
I was going to make something similar to Martin made, then found someone had already come up with a 3d printed solution, so if you have access to a printer this worked great for me https://www.thingiverse.com/thing:4946220
just used a m4x16mm bolt in the locking hole, another m4x16mm in the capitive hole for the bracket, 2 m3x8mm holes to secure the bracket to the 3d part and a m4x25mm or 30mm bolt to tension the focuser
Nice neat purpose built solution
Thanks for posting
After I designed and fitted my $10 solution on 2 Newts ( which are still working perfectly) , a few weeks later I found this custom bracket on the Teleskop Express website specifically designed for GSO crayford focusers
