A new 22" dob is being born

[Pablito]

Hello again after longer break

Finally I had a chance to do focusing test yesterday. Everything is perfect, no need to cut and now I can  put a black paint on the poles. Good balancing and scope is moving smooth. 

Street lamps flashed straight into the dob (don't have light shroud yet) but M57 was still very nice

[Andy_E]

Great work Pablito... really looking forward to a full on first light report! Love the finish on the mirror box too, very different to the mock-Victorian mahogany effect on mine!

[estwing]

great work and well done...good luck on your proper first light

[andyman]

WOW thats a cool looking scope 

[dezzie]

The fellas at my local club are building a 22" dob too, this looks awesome and hopefully when ours is done I can post pics too!

[arrayschism]

Really looking forward to a first light report on this

[WaveSoarer]

It looks great.

[Big_Daz]

WOW That's a beauty.

[crashtestdummy]

Looks amazing,hope my project build looks as good as this does!!

[Peter Drew]

I'm in the process of refurbishing my 30" F4.1 Dob, housing half finished as well.

[8kids]

I'm in the process of refurbishing my 30" F4.1 Dob, housing half finished as well.

That's a big dob. Do you have any photos?

[Peter Drew]

Taking some as I go along, don't hold your breath! 

[wookie1965]

That`s a lovely build cracking scope well done makes me want a dob now.

[Pablito]

Hello,

Thanks for good words  I have a couple of pics with completed scope.

P.S. Peter, I am starting making 30" the next month

[Peter Drew]

Look forward to seeing that Pablito, it obviously won't be much problem for you!. Mine is in the simplest original form of Dobsonian, John Dobson personally signed the rocker box as a seal of approval during his visit to the UK in 2002.   

[Moonshane]

That's a truly lovely scope. I really like some of the strengthening features like the double ring on the underside of the UTA. the UTA is quite short, will you have to take anti dew measures on the secondary?

[Pablito]

How heavy is your 30"?

This 22" weights ca. 65kg in total. For me it's still too much but there was no intention to loose weight. Had no time to do it and my customer didn't  mind it. I am during making 24" structure and I already make it lighter where I can. I use three layers of plywood (4mm+12mm or 15mm+4mm) and in 12/15mm I make holes, after giving 4mm from both sides it's lighter and still stiff. Much more work but result is great

[Pablito]

Moonshane, if it will be necesary, I will use black HIPS or thin terrarium/aquarium foam to make dewshield.

[Moonshane]

that's what I tend to do too. I am not a fan of gadgets/electronics on my scopes other than a fan.

[Peter Drew]

Pablito. The unscientific answer is VERY heavy, I've no means of weighing it but I would estimate 150K. It's much too heavy for the traditional PTFE bearing design, the rocker box has a stainless steel underplate which is supported by 6 ballrace bearings, the side trunnions also run on ballrace bearings. PTFE pads are used to create sufficient damping and can be adjusted such that both axes require the same effort to move them, one finger is all that is needed to do this. The Telescope will live outside in a blockwork housing and will run out on rails when in use.   

[knobby]

I think that is a thing of Beaty ... Really we'll done !

[Pablito]

Peter, as stationary scope it's not a big deal. I wish to achieve not more than 100kg and if I get under 80kg I will be delighted. Mirror weights ca. 40kg so have another 40kg to put into the structure. It will be portable scope but I can't sacrifice stability to get it lighter. Some things just have to be heavy... We will see, hope it will be lot of fun not a frustration

[Rustysplit]

Very nice work Pablito. I really like the idea of the 3 layers with lightened centre layer, very cunning. A brilliant way of adding stiffness without weight.