AASC pre name change to Astro Optical (pre '77)

[torana68]

Hi all,
Does anyone have any sales docs/catalogues or adds for Amateur Astronomers Supply company pre '77 (pre AOS)? I have some stuff from '77 - '93 (AOS) but nothing from the early years.
Id also like to know when they stopped using the wood mirror cell and changed to the Hall aluminium one (I think al their DK 12.5" were wood?) . I assume the trap door in the OTA went at the time they changed to the alloy cell if that rings a bell with anyone.
Roger

[torana68]

still looking,,,,,

[astronut]

Sorry Roger, no receipts. BUT, I still have my 2.4" Unitron that I bought from them in 1969....ah memories.:)

[torana68]

must have sold a few of those :)

[wulfgar]

I got their "compact" (FL 1000 mm) 6" Newtonian in late 1974. Which had a metallic blue finish. It had a wooden main mirror cell (yuk!). This was spray painted black with some transparent pvc air hose stuck around the base inside the tube to keep the dust out. In the late 80's I replaced it with their cast model, which was a very nice piece. If I remember correctly the cast model was just coming in at the time.

[torana68]

thanks for the info, I'd guess that the cast parts were on the market by '74, you must have just missed out ! how did they perform? any photos?
Roger

[wulfgar]

If you mean the wooden main mirror cell? Not very well, it wasn't refined in its adjustments and didn't hold place very well. It used course 3/8 round headed bolts that served as the mirror floatation points and colomation adjustment. A little bump and it was out. The sort of stuff of home made ATM. The later cast model was simple but excellent, even preferable to basic stuff from America. No photos of the wooden MM cell, sorry. If I find any photos of the scope, I'll PM them.
The spider and flat holder were typical AOS. I think the R+P was a "Royal" for 1"" ep. The finderscope was little 19 mm Unitron. The eq mount was a "Royal" (LNT4)? model with single piece wooden legs and spike tips.
The mirror seemed to be OK optical quality. I sold it 20 years ago.

I do have an AOS 10" F5.6 Newt form the late 80's. (white tube) w/ Samson eq mnt. A/C drive and corrector. The mirror seems decent quality. I recently downsized the secondary to 1.83" with a new spider and holder. Which just fits in for a 1/2 inch fully illuminated field. I moved the Main mirror a couple of inches back years ago. Using the Royal 1.25 R+P with could be low profiled with one of A. Geddes tiny ep collars.
Looks very promising with a 50 mm obstruction rather than the old 60 mm. (make my air cells straight saith the Lord)
The 10" ain't a bad scope for an antique. I only bought it S/H for a laugh and it is proving to be a seriously good instrument.

I'm working on giving it a straight Unitron 8 X 50 finder (late era SCT brackets) that I'm trying to chop to right angle. (been using a Telrad) I managed to get the rear flange bushing out with the aid of acetone. Now if I can get the ep collar out of the bushing I might be able to mate a Carton star diagonal which has a screw thread front.

[doppler]

Good to see that there are some old clasics still around. I still have an old cave astrola from the 1970's. Bought it in 1985. 8" f6 equtorial pier mount, tube rotation rings, 240v single axis drive. The original mirror still has heaps of reflectivity.

[wulfgar]

Must admit that I've seldom used the Samson eq mnt. I found myself climbing a step ladder and converted to Dobby. Tube rotation rings would be a very nice feature if I had them. The weak point of the Samson was the very ordinary straps the held the tube in place. Other than that Alex Stern's machining was very nice and it took the weight and tracked very smoothly.
My other scope is an 6" F8 newt with 1" flat which I converted to pier mnt from a tripod. The only way to mnt long FL / Newtonian's is pier. I assembled that from parts and it was inspired by the classic 6" Newt's of the past.

[torana68]

these must have been expensive new :)

[doppler]

I got mine in 1985 for $1200 secondhand but when you compare what was available at the shops well ..... you can see why I went for the 8" f6 cave with rotation rings and pier mount. (the scope in the second pic is a meade of the same period and the same basic design of mine, and that is a 12" f6 in the background)

Here is a link I found for classic telescope catalogs and manuals http://geogdata.csun.edu/~voltaire/classics/

[wulfgar]

Sounds like one of the "deluxe" models with rotation rings. $650 to $750 USD in the mid 70's.

About $5000 - $6000 in todays money.

Going by the photo's you posted you got the "light weight deluxe model" that lists at 595 USD in a 1976 issue of "sky and telescope".

[doppler]

I am wondering if my scope is actually an older model, the focuser is in a different spot on the tube, the counterweight is fatter and mine has adjustable levelling bolts on the legs. I found this 1975 cave catalogue.

[torana68]

:D thats a nice one! original or have you restored it?

[wulfgar]

The difference is in the equatorial head, yours is the light weight version, you'll notice yours has the thinner "pipes" and lighter bearings. This was a demand at the time for more transportable compact (F6) lighter version in reaction to the SCT craze. Their full weight mount is about as heavy as the AOS Sampson.
AOS had a sort of similar "compact" 8" F6 Newt, with a lighter imported mount at the same time. Minus the tube rings and quality parts. I think theirs was about $450?
Is there much "play" in equatorial axis when it is in drive mode?

[doppler]

You are correct, it is a lightweight delux. The axis shafts are 1" steel rods
(not the original heavy 1.5" ones). I just realised that the scopes illustrated in the
catalogue are 8" f 7's, hence the different tube configuration. There are guide
scope mounting holes on the tube, so I think the original owner had that option
as well, hence the larger counterweight. There is not any noticeable play in the
drive system. For guiding I use a 12V dc to 240v ac drive corector and have
never noticed any periodic errors.
I have resprayed the mount and replaced the mirrors with a set made by
Coulter optical in the US. I will at some stage get the original mirrors recoated.
The originals are made with much thicker blanks. I had to put a weight in the
bottom of the tube to balance it. That is one drawback of rotation rings they are
fixed to the tube. I have also made a mount for 4" f7 achromatic guide scope.

[wulfgar]

The standard focal length for an 8" mirrior was F7 or F7.5 at the time. F6 was compact for an 8" at the time and very new wave. F6 would have been popular with Astro photographers. Your 8" wouldn't require the heavier mount in any case and the lightweight mount is suitable for a 10kg payload. My 10" F5.7 and mount comes in around 60 kg. I can lift it "just" and move it 10 feet or so back into the shed.
You're probably fortunate that your vintage scope is still "with it" due to the 48 inch FL. Anything longer requires a step ladder and people have better alternatives today.
In price compasion a 4" Unitron refractor with EQ mnt and drive was around $900. Almost half a years basic wage in the early 1950's.

I didn't realise speculum mirrors were still common around 1950.

http://www.omahaastro.com/cave/tomcave/

[wulfgar]

A much longer 8", this one requires a step ladder, but still a planetary Newt that eats the best today.
Doesn't appear to be quite F8 though - 64".
60" was a more typical FL for an 8" long focus newt.

http://skyexplorers.com/images/CaveAstrola.jpg

1962 Cave Astrola 8 Inch f/8 Newtonian Reflector Model "B" Deluxe

http://skyexplorers.com/cave.htm

[Wavytone]

Ah, memories.

I built a few scopes in the 70's - but bought a heavy equatorial mount from AASC about 1972-3 when I made my first Newtonians - first a 6" f/8, then an 8" f/6.7 (in those days most 8" mirrors were about f/7-f/8) then a folded 6" f/18.

You can see the mount in these pics... the head was made from steel pipe sections with bronze bushes press-fitted in the ends, with cadmium-plated 1.25" solid steel shafts.

A few years later a worm was made for me by a friend who managed to melt and cast alloy blanks, then machined an 8" worm wheel with 243 teeth, with clutch. At the time I was a bit short of cash so only had hand-cables to drive it, and I thought it wasn't worth motorising. With hindsight it probably would have worked well as this worm wheel was huge compared to anything else around commercially and was quite robust. The alloy was duralumin, which came from an old engine block which I was able to smash into small pieces using a sledge hammer, though they were a bit porous they were good enough for this. I made a fixed tripod out of jarrah floorboards (very solid too) and this sat on a wheeled base on fat wheels cannibalised from a kids trike, it turned out to be stable enough. The baseplate of the mount visible in the 3rd pic was 1/2" steel and those bolts holding the base to the tripod were 1/2" - this beastie was quite RIGID - flexure was not an issue !

The cradle was designed to carry the 6" f/8 and the 8" Newtonians. In 1978 I had come up with a design for a folded long-focus Newtonian and built the 6" f/18 (square plywood tube) shown beside the 6" f/8 for comparison. For those who haven't seen this design, the layout of the 6" f/18 is included.

The mount originally had a piece of tin with a bolt and wingnut to clamp the tubes on the cradle but this was a rather poor solution; seatbelt webbing and some cord did a much better job !

I gave the two 6" scopes to friends in Canberra, and when moving to Sydney sold the mount and the 8" to buy an orange-tube C8 instead which was at least a lot more portable, though the C8 optics turned out to be distinctly inferior and the spur gear drive in the C8 was rubbish in comparison to this one.

Those old enough may remember seeing this scope in the 1981 June edition of S&T:D