Keep your dobsonian telescope base rotation smooth with this simple method

[Tiago Ferreira]

This is an easy, simple and very effective technique to help you to have your dobsonian base rotation always smooth. It is an ancient lubricant method of our civilization and i found on Cloudy Nights the ability to use it on the dobsonian telescope and since then i always use it successfully so worth it to spread the information.

 

[NGC 1502]

Glad the soap bar works for you to improve Dob movements 👍

Unfortunately I’ve found that adding any lubricant only helps for a limited time.  After one or two sessions the lubricant collected dust and crud and the smooth movement deteriorated greatly.  The proximity of the azimuth bearing to the ground was a big factor I think.  Perhaps it’s not a big job to dismantle, clean the bearings and re-lubricate. But I found that clean Teflon pads worked best and lasted.

Other factors for good azimuth movement is the surface that the Teflon contacts.  The bottom surface of the rocker box needs to be clean and exactly flat.  The aluminium that my Orion Optics Dob mount is constructed from has a hard pebbly finish and works well.  It’s precisely flat too.

There’s also the “lazy susan” type lower bearing used by some manufacturers, but I’ve no experience of how well that works.

For me a Dob with smooth movements is a joy to use, but a “sticky Dob” is a right royal pain......

Ed.

 

 

[Tiago Ferreira]

On 03/03/2021 at 19:35, NGC 1502 said:

Glad the soap bar works for you to improve Dob movements 👍

Unfortunately I’ve found that adding any lubricant only helps for a limited time.  After one or two sessions the lubricant collected dust and crud and the smooth movement deteriorated greatly.  The proximity of the azimuth bearing to the ground was a big factor I think.  Perhaps it’s not a big job to dismantle, clean the bearings and re-lubricate. But I found that clean Teflon pads worked best and lasted.

Other factors for good azimuth movement is the surface that the Teflon contacts.  The bottom surface of the rocker box needs to be clean and exactly flat.  The aluminium that my Orion Optics Dob mount is constructed from has a hard pebbly finish and works well.  It’s precisely flat too.

There’s also the “lazy susan” type lower bearing used by some manufacturers, but I’ve no experience of how well that works.

For me a Dob with smooth movements is a joy to use, but a “sticky Dob” is a right royal pain......

Ed.

 

 

with my set up works wonderful. i have the lazy susan too but as i say in the video, no soap there. it works very well to, no lubricant on it.

soap only on the formica path of teflon pads. level doesn't change.

i suppose each set up is different and each one has to understand very well his own set up mechanics and act accordingly. what works well for one can work or not for other.

[Stu]

Interesting method! I recently added a lazy Susan beating to my Orion Optics 8” f8 and it is much better now.

[johninderby]

With my Bresser dob when I built the custom base I reused the teflon pads and the metal ring with the textured finish but fitted some thin 40mm diameter teflon disks to the centre bolt to relieve some of the weight. Now has perfect movement. Moves easily but not too easily. Polished the ring and teflon pads with Turtle Wax original car paste wax  which is the only wax that works properly on dob bearings. No other wax has the right properties. 

[NGC 1502]

All good info above on this topic. I think it’s a case of try it and see what works for your scope.

One of the great things about Dobs is the many DIY improvements that’s possible, to make a good scope into a superb one 👍

Ed.

[Tiago Ferreira]

4 hours ago, Stu said:

Interesting method! I recently added a lazy Susan beating to my Orion Optics 8” f8 and it is much better now.

Yeah, lazy susan is very nice. Even in my set up completely modified as you can see in the video picture, it works very well.

I was in doubt because of the lack of base, now i have the Y base but even with only 3 arms to support it it performance well. I had to add friction on each arm, you cannot see that in the pictures but that rubber band friction i add is enough to it.

Each set up has its "particularities" 🙂

Observing at very high magnifications and framing with a ZWO224 and a barlow is an excellent test to the dob smoothness.

[Starwatcher2001]

I've always found that getting the right "feel" for a Dob is a balancing act between smoothness, but also a little "sticktion". Too smooth and it can move in a wind, to much stick and it takes too much force to nudge and overshoots. When I built mine I used a tapered roller bearing (from a GS750) in the centre, teflon sliders and an adjustable clutch so I could vary the feel.

Lubricants never helped due to problems mentioned above, and temperature.

Edited March 5, 2021 by Starwatcher2001
Added a bit

[Spile]

I don't have a problem with the default Teflon pads. I tweaked the tightness of the central bolt so the discs would move freely but not be too loose.

I've heard some have used a couple of CD's as anti-friction mounts which I suppose could work.

I thought about carnauba car wax but then what is the point when there isn't an issue?

 

[Starwatcher2001]

On 03/03/2021 at 19:35, NGC 1502 said:

The aluminium that my Orion Optics Dob mount is constructed from has a hard pebbly finish and works well.

 

John Dobson's original design used an LP record as it has a grooved surface. The Sidewalk Astronomers, founded by John, later moved to a pebbly finish much as you describe and found a product called "Ebony Star" gave a smooth action.

I had the pleasure of meeting John in Pontefract in 2002, courtesy of the West Yorkshire Astronomy Group. He was quite a character and told a good many fascinating stories, not just about astronomy. He was a very knowledgable guy.

 

Edited March 5, 2021 by Starwatcher2001
uploaded wrong image

[NGC 1502]

Well done, what a privilege to have met JD.....👍

[markie]

Hi All

I was looking at doing  something with my Bresser dob base, I'm thinking of getting 2 embroidery rings from my local Hobby shop, they're not expensive , I would be getting 1 slightly smaller than the first,  then fasten them to the base , then get some ball bearings of the correct size, put them between the embroidery rings, then put it all back together, 

Does anyone have an opinion or do you think it wouldn't work?

 

 

Edited August 11, 2023 by markie

[bosun21]

1 hour ago, markie said:

Hi All

I was looking at doing  something with my Bresser dob base, I'm thinking of getting 2 embroidery rings from my local Hobby shop, they're not expensive , I would be getting 1 slightly smaller than the first,  then fasten them to the base , then get some ball bearings of the correct size, put them between the embroidery rings, then put it all back together, 

Does anyone have an opinion or do you think it wouldn't work?

 

 

Just buy a lazy Susan bearing. They are relatively inexpensive and work great.

[markie]

I've read conflicting stories about lazy Susans, but will probably try a few different ideas until I come accross the one that suits,

Thanks for the reply

[Louis D]

On 05/03/2021 at 14:38, Starwatcher2001 said:

John Dobson's original design used an LP record as it has a grooved surface. The Sidewalk Astronomers, founded by John, later moved to a pebbly finish much as you describe and found a product called "Ebony Star" gave a smooth action.

I had the pleasure of meeting John in Pontefract in 2002, courtesy of the West Yorkshire Astronomy Group. He was quite a character and told a good many fascinating stories, not just about astronomy. He was a very knowledgable guy.

 

My photographic OCD side kicked in when I saw that picture and decided to see what I could do to clean it up a bit.  Here's the result: