Thursday, September 29, 2016

More on Curtis' 12" F4 . . .

Out with the old, in with the new. Here's Curtis' 12" F4 OTA
"before and after". It's considerably lighter. Note the two Losmandy
4" dovetails on either side of the OTA. Curtis will be able to
rotate the OTA 180-degrees for imaging, if needed.

The telescope will be mounted on an German equatorial.

Tuesday, September 27, 2016

A 12" F4 OTA for Curtis.....

The tube components for a 12" F4 OTA. This will be a 6-strut design with two
4" Losmandy-type dovetail plates, one mounted on each side. Here you 

see the mirror cell,  3" focuser and spider mounted Curtis intends 
using the telescope for imaging. Curtis lives in Orange, California.

Saturday, September 24, 2016

16" String-Strut Kit for Grant Complete . . .

Grant's string-strut kit. The only components Grant will need to supply
are the spider, secondary, focuser, primary mirror and cell.

Thursday, September 22, 2016

Grant's 16" Kit Just About Complete . . .

A dual fan assembly for Grant's 16" string-strut kit. With this
component, the kit is 99% completed. 

Wednesday, September 21, 2016

Zac Begins Building His Kit . . .

A neat beginning to building his kit, Zac, in Georgetown, Kentucky, starts by applying some graphics. It'll be interesting to see this telescope come together. Here's what Zac has to say:

"Dennis -- Getting some graphics in, these are rub off letters that i have used on models for years, you place the plastic backing over it and rub three the plastic to apply the letters, they are super thin and will be glossed over and will never come off."

Monday, September 19, 2016

A Couple of Photos and a Note from Wyatt in Dallas . . .


Hi Dennis, Here is my DobStuff XT10 conversion out on my driveway in Dallas for some observation of Jupiter on Saturday morning, December 19. Just average seeing, but I still managed to watch a good part of an Io transit over about an hour with some reasonably clear views throughout the session. The scope is really great to use.

Back when you were doing the build for me, I mentioned that primary mirror cooling was one of my main reasons for doing this. I now run both the mirror cell fan and (don’t laugh…) a second cooling fan as shown in the picture. This homemade implementation – rubber bands and all — works really well. The cooling power is greatly increased and I don’t notice any vibration/image blurring. (I have tested it with the second fan both on and off on during planetary observation like the one from yesterday morning.)


Anyway, FYI and thanks again for the great scope! - Wyatt

A Couple of Projects.....

Grant's 16" telescope project is coming along. Here, Grant has asked
for the "strut rocker box". It lightens the weight and is still very rigid.

A 13.1" 6-point flotation mirror cell for Stephen in Wayland, Massachusetts.

With the adjustable back plate, the mirror cell will easily fit
Stephen's 16" telescope tube.

Sunday, September 18, 2016

Grant's 16" Rocker Box and Altitude Bearings.....

A good start on Grants 16" rocker and alt bearings. Here, the bearings
are just about complete. The rocker box sides need just a touch more work.

Saturday, September 17, 2016

Wednesday, September 14, 2016

Zac's 14" Kit Complete . . .

A full 14" kit for Zac, in Georgetown Kentucky, completed today. This
kit includes all components for the telescope -- 14" Hubble mirror,
Antares 1/15th wave secondary, Moonlite focuser and Destiny spider.

Also included, and partially installed, is a Sky Commander digital
setting circle. The struts have been pre-measured and cut.
All packaged up and ready to go.

Sunday, September 11, 2016

Zac's 14" -- Rocker Box and Altitude Bearings. . .

Zac asked for solid rocker box sides. Otherwise, it's virtually complete.
I always assemble the rocker with clamps to check for the fit.
In this case -- it's just right!!
Zac's 14" strut kit is close to completion. Here are the rocker box sides,
altitude bearings and bearing-clamps are completed.




Tuesday, September 6, 2016

Hello Test. 1, 2, 3, 4....

One final task is to do to properly set the strut length is to
setup the optical system and perform a star-test.

I set the struts with a simple-to-use system as found on this webpage:
http://dobstuff.com/struts.htm
The adjustable test struts let me fine-tune the length as needed.
In this case, this 14" F4.6 has struts that are 63.5" in length.

Monday, September 5, 2016

Zac's Mirror Cell and More . . .

A Moonlite 2" crayford focuser.
The 3-vane spider is a Destiny. Note the Kendrick secondary dew heater installed.
The top ring for Zac's OTA is complete. The secondary is a
2.6" Antares 1/15th wave optic.
A good sized ventilation hole for cooling during setup and use.

The 6-point cell on the mirror board.





Sunday, September 4, 2016

More on Zac's 14" Strut Telescope Kit . . .

Zac's OTA rings are pretty much complete. This set has the ETT
(Easy Transport Telescope) option. The mirror cell is under
construction. To be mounted is the spider and focuser.

Saturday, September 3, 2016

A 14" Kit for Zach in Georgetown, Kentucky . . .

A 0.98 strehl -- not bad.
An F4.66 focal ratio.
The 14" mirror as received from Hubble Optics  in Hong Kong.

The mirror is double boxed for safety.
The coating is very nice -- the mirror comes center marked for easy collimation.
This is a "sandwich mirror" -- two glass disks separate
with spacers. Easy cooling. Nice!!