Page 1 of 1

Dob Mods

Posted: Mon Jul 10, 2023 11:19 pm
by Mike Q
I think this is a good time to start what could become a very big thread. Lets talk about the mods that we have made to our reflectors, dobs or otherwise. Maybe you have an idea no one has thought of yet, so lets share what we have done

Re: Dob Mods

Posted: Mon Jul 10, 2023 11:22 pm
by Mike Q
And i will start. Bobs Knobs replacing the screws on the secondary mirror and new springs on the primary. Much better then the original hardware

The other thing that just made life easier in finding things, a setting circle and angle gauge. Finding stuff is no longer an issue.

Re: Dob Mods

Posted: Tue Jul 11, 2023 1:14 am
by Michael131313
I agree. A setting circle and digital angle guage make life much easier. I followed Richard Walkers advice on Dakota Starry Nights and made a calibrating mount for the angle guage. Sometimes just holding it can be a degree or more off.

Re: Dob Mods

Posted: Tue Jul 11, 2023 5:43 am
by Graeme1858
When I had my 250mm dob I got the CAD people at work to print out a cardinal points image on A1 paper with a diameter to match the base of mount. Then I bought a digital level and fixed it to the OTA. Then I used a phone app called "Where is it" to convert RA/Dec to Alt/Az. Stuff was quite easy to find!

Graeme

Re: Dob Mods

Posted: Tue Jul 11, 2023 9:25 am
by Mike Q
Michael131313 wrote: Tue Jul 11, 2023 1:14 am I agree. A setting circle and digital angle guage make life much easier. I followed Richard Walkers advice on Dakota Starry Nights and made a calibrating mount for the angle guage. Sometimes just holding it can be a degree or more off.
My angle gauges have a magnetic base and it sticks to the OTA. I level to the base and then stick it on the OTA. Anything i look for is usually within the field of view of my 30mm eyepiece to start.

Re: Dob Mods

Posted: Tue Jul 11, 2023 9:26 am
by Mike Q
Graeme1858 wrote: Tue Jul 11, 2023 5:43 am When I had my 250mm dob I got the CAD people at work to print out a cardinal points image on A1 paper with a diameter to match the base of mount. Then I bought a digital level and fixed it to the OTA. Then I used a phone app called "Where is it" to convert RA/Dec to Alt/Az. Stuff was quite easy to find!

Graeme
I have a fixed circle on my 10 inch which works well, and a adjustable on the 16. Mine are wooden and made by Mark at Astrogoods in California.

Re: Dob Mods

Posted: Tue Jul 11, 2023 12:56 pm
by helicon
I added a Rigel Quikfinder to my old Dob, which may or may not be considered a mod. About 15 years ago I also built a 6" f/5 Dob on a set of rolling wheels I purchased from Ace so it could be rolled out onto the driveway. My kids used it plus we also did some outreach at their school for science night.

Re: Dob Mods

Posted: Mon Jul 17, 2023 12:33 am
by SkySurfer
Yes to Mike Q's suggestions for knobs and a magnetic angle gauge. My dob came with knobs (Orion XT8+) and I'm sure it would have taken me four times as long to figure out collimation if I had to muck about with a screw driver.
Other items I've added are:
Baader SkySurfer III red dot finder. I find the dot is smaller and the lens is brighter than the stock one it came with, so if I know exactly where I want to point, I can hit most targets with a 5mm Paradigm in the focuser.
2" Baader ClickLock eyepiece holder and 1.25" adapter which make swapping out eyepieces a snap. Much easier to work than thumb screws, especially in the winter with gloves on and they pretty much eliminate the issues I had with undercuts.
Asterion EQ base for tracking which makes sketching and taking notes sooooo much easier. NOTE: following the sage advice of Don Pensack, I never leave our dob on it unattended anymore. I luckily never had an issue with it, but he mentioned that they can be tippy, especially in the wind. Fortunately our dob is light enough to lift off without separating the OTA from the dob base so this is no trouble.

Re: Dob Mods

Posted: Mon Jul 17, 2023 2:47 am
by SkyHiker
I took the saw to my solid tube Z12 to make it collapsible. In first instance I used carbon fiber poles provided by the company I worked for. later I switched to aluminum struts with wingnuts. It now fits in my car taking one seat not three. In retrospect I should have got a Skywatcher collapsible Dob to save myself the trouble. I just could not resist the $630 price new when Apertura and Zhumell were competing.

I added manual setting circles for both Az and Alt, and a foldable stand with adjustable feet.

I also made an equatorial platform. It is dual axis and can be autoguided.
IMG_0972_small.jpg

Re: Dob Mods

Posted: Mon Jul 17, 2023 11:17 am
by 10538
On my 14 inch I automatically changed out the secondary screws for Bob’s Knobs. I added (5) Kendrick Fire Flies dew strips and heater, I flocked the inside of the scope and painted all the screws and nuts flat black. I added several pounds of leg weights to the rear of the scope using industrial strength Velcro. I changed out the factory focuser and replaced it with a MoonLite focuser, I love it! I added no-flat tires to the cart and increased the size a bit. I made a rear dust cap because it didn’t come with one. I added a 9 x 50 RACI, also a Telrad that I took off later, a laser for quick pointing, glow in the dark tape on the top of each leveling screw so I don’t trip over it in the dark, bought a clear plastic case for the controller and added Velcro to the back of it and to the OTA next to the focuser so I don’t have to hold it. After trying several different methods to power the scope and heat strip’s I decided on (2) Celestron LiPo batteries that are very lightweight and run all night long.

Re: Dob Mods

Posted: Mon Jul 17, 2023 3:44 pm
by Richard
made a dobs from an old Tasco but gave it away to the needy

Re: Dob Mods

Posted: Sun Jul 30, 2023 10:22 pm
by Mike Q
One of the best mods i have done is adding a green laser pointer and upgrading to a Stellarvue 13x80 finder scope. Nothing like putting a refractor on your reflector

Re: Dob Mods

Posted: Tue Aug 01, 2023 1:02 am
by 10538
I usually don’t observe when the moon dominates the sky. Actually we haven’t seen the moon or anything else lately due to the storms coming through most days. So being fairly bored, I had an idea to do a couple of upgrades to a 54 year old Criterion RV6 reflector. I’ve taken care of it over the years and surprisingly the mirror is in great shape but the 1 1/4 inch focuser is very simple and crude. I decided to replace it with a 2 inch GSO dual speed focuser. It took a while to figure out how to enlarge the hole in the tube to 2 1/2 inches. After a nervous couple of hours I installed the new focuser and adjusted the mirrors using a laser. I also replaced the very small finder with a 9x50 RACI. I checked out some tree tops afterwards and it seems to perform beautifully. Can’t wait to try it once we get a clear night.