Saturday, March 31, 2018

A Couple of Trusses -- A Couple of Struts...

I currently have a couple of truss and a couple of strut telescopes underway.
They'are all about the same size, so I'm able to "cut wood" for them
all at the same time!! This photo shows the OTA rings for the truss
telescopes in the very early stages.

Thursday, March 29, 2018

Tuesday, March 27, 2018

Phillip's 8" F7 Completed . . .

Every time I build one of these telescopes, I want to keep it. This one is a beauty -- with excellent optics and motions. The finished product includes a curved-vane spider, a manual or motor driven focuser and secondary dew heater. A complete Sky Commander system rounds out the beautiful features of this telescope.

Note the  Easy Transport Telescope option.

Monday, March 26, 2018

Philip's 8" F7 -- Just About Completed...

An 8" telescope, especially one that's a "little longer" needs to be stable.
Here, the ground board is outside the center of balance for stability.

The azimuth motion is great. 

Dave's 17.5" -- First Light ...


Got the big dob out to the park about 7 and had it set up and collimated in 20 min.  With practice that should be under 15 min.   I’m a total klutz, so that’s a credit to your truss design, not to my assembly skills.  Took another 5 minutes to dial in the 50mm finder. 

In the bright twilight my first target was Venus.  At -3.9 Venus was painfully bright, like an oncoming motorcycle with the Hi Beam on.  The scope resolved the nearly round disk sharply at 100x, using a 20mm TeleVue Nagler.

Sirius appeared, and high above it the slightly gibbous 1st qtr moon.  I needed my new Costco 2 step kitchen stool to get to the eyepiece but it was well worth it.  The moon was jaw-dropping.  Wow!  The Lunar highlands around Tycho and Clavius, near the terminator, were razor sharp with rills, small craters and details

I’ve never seen before in any scope I’ve owned.  Just stunning.  I couldn’t stop looking.  Focus tweaks and eyepiece changes damped down quickly.  The scope moved smoothly in all directions and has just the right ‘sticktion’ for my heavy 2” eyepieces.  Never needed to adjust the weights.

Just as it was getting dark enough to consider a few brighter deep sky objects the clouds rolled in so I reluctantly packed up and rolled out.  Far too short a session but long enough to demonstrate that the optics are just fine, and the design and build is excellent.  Can’t wait for a clear sky and new moon!


Saturday, March 24, 2018

A Note from Dave and his 17.5" Truss . . .


Impressive sight against an 8 ft ceiling, but very smooth and stable in both Altitude and Azimuth. 

Big but quite manageable when broken down.  The ball joints make truss assembly a breeze!

In fact, the entire assembly was quick even without a manual thanks to the great photos from the blog.  They answered every question.

Denks and mono eyepieces all working.  Collimation was quick and easy.  Just waiting for dark skies!

Philip's 8" F7 on its incomplete rocker box. I need
to finish the bottom and add the Sky Commander.

Some detail of the mirror box, altitude bearings and rocker box.

Note the red dot finder and secondary dew heater on the top ring.

Thursday, March 22, 2018

More on Philip's 8" F7....

Philip's 8' F7 is a "bit" longer than the usual
4.5 -- hence the slightly higher rocker box sides.
The OTA (optical tube assembly) is pretty
much complete with the addition of the
altitude bearings.

Tuesday, March 20, 2018

Philip's 8" F7+ OTA

Philip's 8" with Easy Transport Telescope option. 
Philip supplied his mirror cell for the mirror board.
I make a custom mirror cover for all the telescopes I build.
The detail of Philip's motorized focuser and 3-vane
curved-vane spider. A Kendrick dew heater is included.

Saturday, March 17, 2018

Phillips' 8" an Interesting Fix ....

I initially mounted Phillips spider on "top" of the top ring only to find
the secondary mirror was unable to come directly under the focuser.
I need "more length" along the optical axis.

I remounted the spider "under" the ring and voila!!  I was able to
bring the secondary holder and focuser into alignment.

(note the red laser collimator dot)

One issue was the placement of the spider vane. A "fix" took
care of that issue. Looking and working great!!

Friday, March 16, 2018

A Note from Howard and his 16" Telescope...

Howard sent along a nice photo and note:

Hi Dennis, I decided I needed some wheels on this 16"
 to move it around observing sites easier. Seems to work well.

Wheels stay on although easy to remove if need be.
 I just used some electrical conduit for the handles
so they just slide in and out. I use hose clamps to
hold them in place so they don't slide out when I am
moving it and it is quick to remove them
with a screwdriver when I need to move it.

Wednesday, March 14, 2018

More on Phillip's 8" F7.42 ...

The top ring for Philips 8" telescope. The ruler will give you
a sense of size and scale.

Altitude bearings and rocker box sides for Phillip's 8" strut telescope.

Dave's 17.5" F4.5 Truss Telescope Completed . . .

This 17.5" F4.5 truss telescope features a Destiny
Observatory grade 3-vane curved-vane spider, Moonlite
2-speed focuser and 6-point flotation mirror cell
designed and optimized with plop.

Note Dave's nice 8x50 finder and detail of the spider.

The all aluminum 6-point flotation mirror cell. Three
simple collimation thumb knobs it all it takes to
bring the telescope into perfect alignment.

A Denkmeier binoviewer rounds out Dave observing options.

Tuesday, March 13, 2018

An 8" F7.42 for Phillip....

While I'm putting the finishing touches on Dave's 17.5" truss telescope,
I'm making some headway on Phillips 8" F6 strut with ETT.

Friday, March 9, 2018

When you need a custom scope built fast, contact Dennis at Dobstuff.

John lives in Richmond, Virginia.

Late last year I found an 8” f/4 Ed Beck Enterprise Optics primary and matching secondary on Astromart. (I don’t know the make of the secondary) It has a surface blemish about 1” long that does not affect views. I had never hear of this maker before. I was intrigued by the ideas of vintage optics, wide field, sufficient aperture, and easy portability. My first though was a small dob, but then I remembered seeing some Dobstuff newts with integrated Losmandy dovetail. This allows both alt-az and equatorial use. 

At the star party the ATM guys set up the mirror  in in the Focault tester. It showed smooth figure and no other defects. This was readily apparent compared to  other mirrors were tested. I went ahead and had it recoated by Ostahowski (highly recommended) and then on to Dennis for the build. Many emails  were sent back and forth, and about a month later, the scope arrived. 

It has a simple strut design. The rings have a flat side for direct attachment of the dovetail Its also attached to the aluminum truss. Moonlite focuser and filter slide. Dobstuff secondary holder keeps collimation well and easy to adjust thumbscrews. Dennis provided the mirror cell with fan and three thumbscrews for no-tools collimation. Rubber feet allow the scope to stand upright for storage. Two wood rotating finder bases on the truss next to the focuser. Can accommodate reflex or optical finders. 

Things I added:

I started with a 13” Losmandy dovetail, then changed that to a 26” for wider range of balance.

I forgot to ask for a secondary dew heater. (Duh!) Ordered  the Kendrick split heater and glued it with some silicone. I also added a forward platform for the Telrad. I like it ahead of, not next to the focuser.

I have a Lycra shroud from another scope that fits after minor alteration.

First light was under dark semirural skies. With a Paracorr and 21 Ethos, magnification is 45x and Field  of View around 2.2 degrees. This was plenty to see Orion’s Sword region all at once. Thor’s Helmet nebula was easily seen , and even better with a UHC filter. With a 4.5mm Delos giving 208x , observed M79 in Lepus and planetary nebula IC 418. High power isn’t ideal for alt-az use, but I had no issues. The mount is the highly regarded  Discmounts  DM6. No backlash and easy tracking. First light was a success. I was able to observe a number of DSO’s and double stars. 

Second light was at home under a bright bright waning gibbous moon. I used a binoviewer with 2x OCS, and eyepieces from 32 to 11mm. A Lumicon ND25 filter reduced the glare. The scope again provided excellent sharp views, although the seeing was poor from a cold front. The best feature of the night was Vallis Capella. https://en.m.wikiped...Capella_(crater)  It was so distinct I ran in the house grab the Rukl Lunar Atlas. I’ve seen the crater any number of times, but never the Vallis.

Thanks John...

Tuesday, March 6, 2018

Dave's 17.5" F4.5 Gettin' Closer ....

Dave's 17.5" Truss Telescope in its partially completed rocker box
for fit and function. 

The altitude bearings are 25.5" in diameter. Just right for this size telescope.
The eyepiece is at a height of 73.5" at the zenith. One step will do it!!

Monday, March 5, 2018

And While the Varnish Dries . . .

While the varnish dries on the 17.5" Truss rocker box,
I've started Philip's 8" strut telescope with Easy Transport
Option. Here his mirror cell is modified a bit and in place.

Sunday, March 4, 2018

Something a Bit Different . . .

An acquaintance told a friend of  hers that I build and fix telescopes. The
next thing I knew I was upgrading and repairing a 4" refractor for
Phillip here in Palm Desert. He built it as a kid of 12 years old. The
lens seems to be from an old military camera and has an "iris" (not used).

Kinda neat, actually!!

Friday, March 2, 2018

A 10" Kit for Marcus with . . .

Marcus' 10" string-strut kit all completed and ready to package then ship.

An unusual request for a strut telescope is a "full upper tube assembly".
Here, the UTA will affix to the top of the string-struts.

And, "Every Now and Then" . . .

It's always nice to get a new order. But nicer, still, when someone
refers you on a forum. THANKS JOHN!!

Thursday, March 1, 2018

Dave's 17.5" F4.5 is "Rockin'" . . .

With the OTA pretty much completed, it's time to start
assembling the rocker box (the aluminum "silver" support
struts will be black in the final iteration).