6 inch truss dob project

[Ggeo]

Hi all,

Looking to build a 6 inch truss dob using a mirror set from a tal2 which I can pick up for about £130. Couple of questions,

1. Is it a worthwhile project?

2. Should I get an 8 inch mirror set instead? I already have a celestron n6 but this would be my first build project.

3. Could I mount it on my current mount or will the c of g be way out?

4. Any other pitfalls in making my own scope?

Thanks in advance,

George

[gliderpilot]

1. Yes it is worthwhile but only you can really be the judge. It certainly isn't financially worthwhile particularly if you compare the cost of a second hand scope. That being said, I got a tremendous buzz when I had my first light through my homemade 8.5" newt.

2. Up to you really. Yes the views would be better through an 8" but not in a dramatic way but the cost also goes up as does the weight and other such design issues.

3. You should be able to use it on your existing mount. Just make sure there is sufficient space for a dovetail. I find this website very useful for design ideas Telescope Building Projects - Newtonians and am considering a 12" using some of the design ideas.

4. You'll want to make another one but with twice the mirror diameter; you spend a fortune on tools justifying them that you'll use them for diy afterwards; you can't go the tip without checking out the metal bins for anything useful ....

[luukieboy2]

1. Yes

2. I should start with a 6 inch mirror

3. Depends on which mount you got, but yes it is possible

4. You could look to this site, Stathis ATM Page , go to the left and click '6.6" twins'. Within some days I'll start a topic about it, with an 8 inch F/6 mirror.

But what kind of telescope would you like to make? Do you want more portability? I do, mine telescope just isn't transportable on vacation, too big.

[Ggeo]

Thanks for the replies,

I'm going to give the 6 inch a go, then if all goes well I'll move onto a 10 or 12 incher !!

[earth titan]

1. Stathis ATM Page

See the 6.6" twins section.

I'm constantly amazed how many people have done simple but effective designs. This solves, and makes simpler, my forthcoming 8" scope OTA. Two simple alluminium strips - brilliant !!!

[Trull]

I used to have a mono-pole design on a 8-3/4" dob, which worked OK, but was loads better as a twin pole. I'd recommend a twin pole design secured with bicycle seat post quick releases for speed. This means you don't have any awkward angles to deal with.

[FraserClarke]

The reason people build truss dobs is for stiffness. The truss's have triangles in every direction, which makes them very stiff in every direction (if done properly). Things like two strips of metal, or a single pole will not have anywhere like the same amount of stiffness (for the same weight at least). However, in a small scope like a 6--10-inch -- they're probably more than adequately stiff anyway. So, unless you want to absolutely minimise the weight, it's probably not worth building a truss this small. It will look immensely cool though...

The classical version of a mono-pole design is of course the tube

[Ggeo]

OK Update time. I've only gone and bought a 10 inch dob, aperture fever strikes again. Managed to get a good deal second hand on a Revelation dob for less than the cost of the primary. Picking it up tomorrow, can't wait. Will probably fit a dual speed crayford so a bit of modding is on the cards.

Any thoughts on the Revelation 10 inch dob?

Thanks,

George