Jump to content
  • Join the online East Midlands astronomy club today!

    With active forums, two dark sites and a knowledgeable membership, East Midlands Stargazers has something for everyone.

Dob setting circles


Guest Fluke
 Share

Recommended Posts

I've just skipped through the epic 'Degree Circles' thread on CloudyNights.com.

Has any of our group had a go? I know Daz is keen to mod his, and Martyn has mentioned it before too...

Anyone know of any UK suppliers of the laminated circles? I've done a few Google searches to no avail

Cheers, Dan

Link to comment
Share on other sites

Mick (doc) definitely did his when he had his big Dob Dan. He's the man to speak to Re: Dob mods :)

Link to comment
Share on other sites

Thats what I'm going to use next when I get round to designing a new dob, do away with the degree circle.

As long as the shaft goes into the ground board and is secured it will work fine.

Link to comment
Share on other sites

Yes, similar, but uses an encoder to measure rotary motion. I have one which came with the scope, you just need a modified M10 bolt for it to fit in. This will mean modding the base a bit, but it's easy to do.

Thanks to Damian letting me have a old lappy of his, I can now use it, getting the co-ordinates off Stellarium.

Link to comment
Share on other sites

Yes, similar, but uses an encoder to measure rotary motion. I have one which came with the scope, you just need a modified M10 bolt for it to fit in. This will mean modding the base a bit, but it's easy to do.

Thanks to Damian letting me have a old lappy of his, I can now use it, getting the co-ordinates off Stellarium.

Sounds great! Any chance of some pics of your base as I cant really picture the mod?

Link to comment
Share on other sites

Iam having trouble loading the pic.

Basically what you do is get a hole drilled down the top of the M10 bolt head, so that the shaft of the encoder fits into it. A hole is drilled and threaded from the side of the head, so a grub screw tightens onto the shaft and locks it in place.

The bolt has the nut under the base board, and tightened so that it all moves just right. A plate is made to stop the nut rotating when the board moves, that way the movement is picked up by the encoder, as the bolt stays where it is.

Clear as mud when I read it back, I'll see if I can take some small file size pics. It really isn't as difficult as it sounds. If I can get hold of some bolt's I'll drill them and mod them to suit, all I will need is the dimensions of the encoder shaft.

If you are thinking about getting one, ask about the longer cable, so you can have it mounted up by the focuser.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.