Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Well I must say that this project just snuck up on me, and the next thing I know, I'm building yet another scope. I have always wanted an 8" F4 newt. but never pulled the trigger on one when they were avaliable.
I didn't want to start from scratch like before, so I found an 8" f6 DSH tube, (Thanks TomL!!) and will use its parts for the build up.
First up was the tear down and getting the end rings refined for my tastes. The mirror cell also needs a fair amount of work too.
As for parts, I will need to pick up a 2 speed GSO focuser, rings for the tube, a secondary mirror, an 8" f4 mirror, and custom build an all aluminum secondary holder.
So lets get started! 
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
I don't have any before pictures, but this is the front ring. I cleaned all the old paint off with my bead blaster. This won't damage the aluminum and will require much less sanding. In the photo you can see the casting "nipples" on the inside of the ring. Those have to go! I used a 3" die grinder to remove the bulk of the material and then finished off the sanding of the inside for a smooth finish.
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Here is a shot of the ring after the inside and outside have been cleaned and sanded smooth. The ring will be powder coated when its done. All I have to do now is hand sand with 400 grit wet\dry sand paper.
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Next up was the mirror cell. It needed a lot of attention. Bead blasting was first and since the ring is a cast piece of aluminum, it wasn't perfectly shaped for a lathe. I ended up using a drill press with a variety of bits and sanding discs to clean it up and flatten the surfaces.
This piece will be powder coated too and is all done at this stage.
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Here is a shot of the back side of the mirror cell.
--------------------
Equipment Overload!
Kerry.
|
Tom L
Reged: 01/07/04
Posts: 29817
Loc: Sunny Oregon
|
|
This is gonna be fun!
--------------------
Tom 
Tele Vue 102mm f/8.6 on an EzTouch
Vixen 80mm f/5 A80SSWT on a grab-n-go mount
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Here is a shot of the end ring after bead blasting.
It was then finished and smoothed on the face and will be hand sanded with 400 grit wet\dry sand paper, and then powder coated.
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Here is the mirror end ring with the mirror cell installed. I happen to like the collimation bolts, so those will stay the same.
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Same item just flipped for the camera.
--------------------
Equipment Overload!
Kerry.
|
rboe
Numbfinger
Reged: 03/16/02
Posts: 39714
Loc: Phx, AZ
|
|
You're the second fellow I've talked with today that has and uses a bead blaster. Dang!
So, wood tube? 
--------------------
Ron
NS11GPS
Pronto
16" dob
15X70 Obies
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Now for the tube. This will be a BIG project. It will need to be cut down to around 29 inches in length, (still to be determined until I get the secondary) and a bunch of holes will have to be brazed shut. Probably some body work too, since the tube will be powder coated when its all done.
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Quote:
So, wood tube?
--------------------
Ron
Sorry Ron, just the stock steel unit. Trying to keep the cost down.
Though a carbon fiber tube would be pretty cool.
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Here is (in my opinion) the worst part of the scope...the dreaded tube seam! I don't much care for it, so it will be welded\brazed shut and then sanded smooth. I have thought of a Hastings aluminum tube and they have several in the 9" diameter that I could use. I may send away for a sample one foot piece of each wall thickness to make sure it will work with the end rings.
Thats of course if the "body" work and hole filling go badly. 
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
The rings arrived from Orion on Thursday. They will be color matched and powder coated to the end rings. But before that happens, I'll have to bead blast all the old paint off and clean up any casting flaws in the aluminum.
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
One problem was that the other ring, (not the one in the photo) had the hinge holes drilled off center by quite a bit. So bad in fact that it will have to be sent back and another new one shipped to me.
This one in the photo is ok but the other one (already boxed for return) had one of the hinge bolts holes off centered by 3\16ths". It wouldn't clamp down on the tube because of the extra play\spacing.
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Here is a shot of the 8" F4 mirror that arrived a few weeks ago. I had a Jim Fly triangle left over and used his mirror centering guage to place it on the mirror.
--------------------
Equipment Overload!
Kerry.
|
rboe
Numbfinger
Reged: 03/16/02
Posts: 39714
Loc: Phx, AZ
|
|
I was looking at a "custom" motorcycle photo and it appeared for all the world that the exhaust pipe was welded up sections of straight sections and arc segments. Very fine weld lines. If you could something similar with the holes and seams then clear coat it; especially if you kept the colour case hardening caused by the welding it could become a design feature of the scope.
You could even add weld spots to make up star patterns.
Not that you would necessarily want a Bad Dog Telescope. 
Pretty cool project though. 
--------------------
Ron
NS11GPS
Pronto
16" dob
15X70 Obies
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Quote:
I was looking at a "custom" motorcycle photo and it appeared for all the world that the exhaust pipe was welded up sections of straight sections and arc segments. Very fine weld lines. If you could something similar with the holes and seams then clear coat it; especially if you kept the colour case hardening caused by the welding it could become a design feature of the scope.
You could even add weld spots to make up star patterns.
Not that you would necessarily want a Bad Dog Telescope.
Pretty cool project though.
Thats an interesting idea Ron, I sure know what your talking about...I have been to quite a few motorcycle shows over the years and love all the fab techniques that people use to build their bikes.
We'll see how it goes. 
What i'm going for is something like Bills scope (Downward Bound), he has the Vixen 8" F4.
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Quote:
This is gonna be fun!
--------------------
Tom
Sure will Tom...thanks to your help in this project and for meeting us in Portland to get the tube from you.
--------------------
Equipment Overload!
Kerry.
|
Sky Captain
Scope Builder
Reged: 11/07/04
Posts: 5743
Loc: Seattle Washington
|
|
Here is a shot of the mirror in the cell. The mirror cell had to be "opened up" a bit to make room for the new mirror. It looks like the stock "8 f6 in." mirror was in the 7-3\4" + range. I also won't use the "clips" that normally hold a mirror in its cell, rather I will use a marine grade adhesive\silicone to secure it in place. I'll use some spacers to keep the mirror "up" while it cures.
--------------------
Equipment Overload!
Kerry.
|
Previous
Index
Next
Threaded
Edit
Reply
Quote
[Re: 