Dob mount build.

[Carbon]

Oversized is good for small dobs.

One suggestion if I may add is to trim out portions of the alt bearings which do not affect the motions of the scope, but still maintain structural integrity. Besides cutting down on weight, it will also make the bearings appear a lot smaller.

[foundaplanet]

So much for a first night out. The sun has been out all day, I got the finder aligned on Vega and then woosh bang , mist, cloud fog or whatever it is.. Well and truly Kylie Minogued.

Oversized is good for small dobs.

One suggestion if I may add is to trim out portions of the alt bearings which do not affect the motions of the scope, but still maintain structural integrity. Besides cutting down on weight, it will also make the bearings appear a lot smaller.

Yes the bearing works a treat cheers.. You are right it definitely needs a bit of something..

[Moonshane]

here's what I did along these lines.

[Carbon]

Moonshane, I've seen your setup before and it's beautiful......quite elegant.

[foundaplanet]

Nice job Moonshane... Elegant.

Can any body give me an idea on the nudge thing please? Is it generally done buy holding the focuser? The reason I ask is that, by shear accident I have two places to very conveniently mount a couple of removable handles. They would locate directly under the front of the scope. I clamped a couple of test pieces on and whilst sitting down, it seemed like the obvious thing to do and was a comfortable place to rest my hands. But, I don't see these on pictures I look at on the internerd.

Edit; Not really handles more like gear sticks.

[Moonshane]

I generally add a 'dob knob'. see below and left from my focuser. this is a kitchen / furniture adjustable foot with a M8 thread, drilled and bolted to the tube. it's a bit like this

it makes the movement of the scope doable with (literally) one finger and mine is a 16" dob especially given the large bearings you have used it will work well. I don't use the focuser as this could potentially create flexing issues.

with a manual dob, I tend to put the object far right (in the newt view) and let it drift left (really it's right but you know what I mean) then move again. even with narrow eyepieces at decent mags (e.g. a plossl at 120x) you get about a minute between nudges.

[foundaplanet]

Oh right yes, I can see that on your image.

I have about 4 mm of remaining thread on the nut head that holds the spider. I may be able to make something up to try this out.

Thanks.

[Moonshane]

Ooooh, I'd not use the spider nuts for the same reasons - will play havoc with collimation. it looks like mine is on the same bolts but it's not.

Best fitting it a few inches away from the spider nuts if you can. I actually made use of some additional holes drilled for some reason by the previous owner. you could always grab the top of the tube but this will be awkward if you have a dew shield and can create warm currents.

[Carbon]

I added a rubberized ball knob on mine.

[Moonshane]

show off

[foundaplanet]

Mmm, yeah course, a bit daft really. Not sure I fancy drilling. I'll try a modified jubilee clip.

[Carbon]

show off

I've since gotten rid of that red spacer thingy and moved the ball knob closer to the focuser.

[foundaplanet]

The base got its first night out last night.

Thought I'd post a pic of the driving gear.. I went for trying out the handle idea mainly because it felt so comfortable. Although I have practically zero dob experience, I'd have to say I am very happy with this. Its a doddle to use.

[Moonshane]

very inventive! dobs are the best option for visual in my book.

[rory]

some fantastic mounts there guys , brilliant. i used a old kitchen cupboard handle on my dob,works a treat apart from the fact its metal and get a little cold on the donny's ! you live and learn.

[Carbon]

That joystick is a cool idea!

[Carbon]

I just noticed you have 2 control sticks. Do you feel the azimuth stick is necessary?

[foundaplanet]

That joystick is a cool idea!

Joystick.. Ha, I like that, very apt.

Interesting you should should ask about the az. Probably not, I did wonder myself last night whether it is absolutely necessary. I guess I will have a better idea when I have used it a little more. I have come at this a little blind really. When I was a kid (to a large degree I still am ) I had a fork mounted 6" scope but I have never really used a dob much at all. So it is mostly a case of have a play and see, although I am a chippy so I have a decent idea of what I am doing with the construction but the mechanic is a case of something new. I just cramped a test piece on to try it first.

I very nearly used four 30 mm dowels to hold the bearings together but figured it would be easier to keep them parallel using two pieces of ply. It was only this which led to the handle and it really does work a treat. It would be interesting for me to see what a dob expert thinks of it in application. For me it seems like the obvious way to move it, I was almost just tracking my objects with minimum effort, sat on my stool with my eye at the eyepiece. Hands comfortably resting on the 'joysticks'...

[Moonshane]

it's a great design. the only thing against it is that leverage is less the further away from centre of gravity you go so it's possibly more effort where it is. but if it works then awesome!

[foundaplanet]

it's a great design. the only thing against it is that leverage is less the further away from centre of gravity you go so it's possibly more effort where it is. but if it works then awesome!

That is a good point. Of course. I will now move the alt joystick to the centre. Thank you for that.

[Carbon]

Correct, there's less effort to maneuver the scope if the joystick is as long as the scope itself.....more leverage and less jitter. This is why a knob or handle mounted on the upper tube assembly works so well.

[Carbon]

Correct, there's less effort to maneuver the scope if the joystick is as long as the scope itself.....more leverage and less jitter. This is why a knob or handle mounted on the upper tube assembly works so well.

But the joystick must be absolutely rigid, the longer it gets. You must also consider balance issues. A long stick will make the scope nose heavy.

But I think when all said and done, the best solution is a small, lightweight handle mounted on the tube.

[foundaplanet]

I gave the base a little bit of cosmetic surgery today.. I shall be ordering a telrad for it tomorrow after seeing one used tuther day.

It still has the joy stick and it seems to work but I now need a dob head to try it out and let me know.