Been and gone and done it now - Bought a Fullerscope

[RLWP]

I must stop looking at Ebay...

I've seen this 8 1/2" Fullerscope reflector pop up several times and not sell. I nearly bought it on the previous listing.

Anyway, according to the handy downloaded Fullerscope document that came with it, it's an 8 1/2" lens, 1293mm focal length. I'm not sure what 'quality' it is, it's probably marked on the back of the mirror under the mount

The tube is a 'Standard' tube - grey plastic with a matt black lining with an optional door (coo!). It's got the standard cradles with an optional slip ring (nice), and a MKI spider support. The focuser is probably the least sophisticated part, a MKI rack mount which is quite crude, and an RAS thread in the end. This is going to have to be sorted to use the eyepieces I have

The mount is a MKIII with optional setting circles, RA manual gear and 45cm flexible drive all standing on a pot mount and pole. It seems to have barbell weights rather than Fullerscope ones

It's big, it's heavy, the mirror looks OK - I wonder if it works?

Note to self: STOP BUYING TELESCOPES!!!

I'll post some pictures later

[Mr Spock]

A classic scope. Optics should be pretty good if not quite up to today's standard.

A new focusser and you should have a solid piece of kit.

[RLWP]

A classic scope. Optics should be pretty good if not quite up to today's standard.

A new focusser and you should have a solid piece of kit.

Now, I do have a nice Crayford focuser here. Except, I'm not using a complete Fullerscope if I do that

Oh dear, originality vs practicality - the restorers eternal dilemma

Richard

[swamp thing]

Now, I do have a nice Crayford focuser here. Except, I'm not using a complete Fullerscope if I do that

Oh dear, originality vs practicality - the restorers eternal dilemma

Richard

Too look at keep the original. To look through, replace it

[damnut]

Would be a classic with a bit of tlc, new optics and mount - New scope then!

[Peter Drew]

First thing to check is the back of the mirror, this could determine how much care or expense could be justified.  Fullerscopes offered mirrors in A,B & C quality, an A quality would be by David Hinds, as good as they come even by today's standards.  

[RLWP]

First thing to check is the back of the mirror, this could determine how much care or expense could be justified.  Fullerscopes offered mirrors in A,B & C quality, an A quality would be by David Hinds, as good as they come even by today's standards.  

I think that's going to have to be one of my first actions, taking the mirror out of it's cell. Where are those brave pills...

Richard

[damnut]

I think Philj may be able to help, he has restored more scopes than I have owned!

[Laurie61]

Welcome to the Fullerscopes club  It's unusual to have a door in a standard tube, perhaps this was a mod by the previous owner ? Your scope sounds very similar to mine, which I bought back in 78, it has grade A optics and performs very well. So well I would not consider parting with it I have part flocked mine and replaced the 1 1/4", dual speed, focuser with a Revelation 2" unit. The optics have a standard coated primary and OO hi lux secondary. 

Mirror in cell. 

[andrew63]

Gosh, this takes me back.  They were functionally but 'properly' made telescopes. Here's my 6inch, only B grade optics but very fine planetary views !  Really no comparison to the  modern synta fare.

Hope you get the scope up and running soon.

Looks like the shed could do with a tidy !

I think grade A was 1/10 wave, grade B 1/8 -  didn't know the had a C grade though.

andrew

[John]

Gosh those photos take me back to the days when I used to hang out at Telescope House, Farringdon Road and chat with the folks there indluding Dudley Fuller.

I've owned a couple of their EQ mounts including one that Dudley made for me from new - took him 4 months to make that as well !

They are solid and rather crude but do the job OK.

I seem to recall that the door in the tube to clean the mirror was an option that was offered.

I hope it's a Hinds mirror, they were generally 1/8th wave PV at minimum.

[RLWP]

I think it's to do with being an engineer - I've always taken my new toys apart

The Mirror cell:

and the collimation nuts:

Much the same as Laurie's

It isn't easy photographing the back of the mirror, however:

So, it's number 753A and has a focal length of 1293mm.

And:

Don't know what the 10/8 means. However, it's a Fullerscope, and is 1/10th wavelength. Together with the A in the number, I'd say it was A grade

Erm, what does 1/10th wavelength mean exactly?

Richard

Richard

[RLWP]

According to the document I have, 'A' quality mirrors are better than 1/10th wave, made of low expansion glass, aluminised and double coated. 'B' quality are also low expansion, 1/8th wave and single coated. 'C' quality appear to have been bought in and were around 1/4 wave

I'd say the original purchaser was quite clever. They didn't buy the 'delux' white tube, instead went for an A quality mirror, a matt black painted standard tube with no end rings but added a door. Likewise they bought a slip ring and an RA manual drive but stuck with the standard focuser

Richard

[Paul M]

Congratulations.

I saw that scope on ebay also. I thought it would be a great addition to anyone's collection.

I can't find my old Fullerscope catalogue. When I see these old images from it I go bleary eyed. Some of my earliest astro memories are of that catalogue. Only after many years of dreaming and then eventually leaving school and getting a job could I start saving up for my first proper scope.

I think mine was what they called their "export" model. Gloss white tube with the access door in the side.

It lives at our caravan in Cumbria now. The OTA is stored in the wardrobe and the mount and pedestal are under a tarpaulin outside.

[Peter Drew]

Good result!   

[RLWP]

Wow, Paul - the Export model appears to be the top of the range with all the options. Very nice

Richard

[John]

Erm, what does 1/10th wavelength mean exactly?

Richard

Assiming that it's accurate and that it's a peak to valley (PV) measurement then It's the equivilent of Orion Optics Ultra Grade. An 8" F/6 mirror by them to that spec costs £504 new. Thats just the mirror.

Should provide pretty good views

[philj]

Congrats on a nice scope there, my mate had one exactly the same as that when I were a lad. We built an observatory and had his 8.5" next to my Tasco 10te.

The views were excellent through the 8.5", I remember seeing some remarkable detail during a Mars opposition in the 70s.Being a refractor man I don't know what their coding was but I suspect you are right with the 10th wave for the class A mirrors. 

Yep Fullerscopes Export range were the fully tricked out versions of each model. I always wanted an export 4" F15 refractor but Im having to slum it with the deluxe

[RLWP]

So, the focuser. I think a possible problem is going to provide my solution.

On the right, the Fullerscope rack focuser with RAS 1 1/4" thread. On the left a Revelation dual speed Crayford 2" focuser with 1 1/4" sleeve. I think it's called progress?

Anyway, the issue:

The Fullerscope draw tube and focuser is carefully designed so that when fully 'in', the end of the tube is flush with the inside of the telescope tube. The Revelation (another Ebay bargain) projects a lot into the tube when fully 'in'. On the other hand, it doesn't go as far 'out' as the Fullerscope one.

What I think I will do is make an adapter that uses the four Fullerscope holes. The adapter will  be thick enough for the fully 'in' Revelation draw tube to touch the outside of the telescope tube. I'll lose about 4mm of 'in' travel but gain a lot of 'out'

I'm not planning to modify the telescope tube. The cone of light from the mirror must already pass completely through the aperture in the main tube, so opening it out to pass the Revelation draw tube doesn't seem to add anything

Have I got my reasoning correct? Also, what's the proper description for 'in' and 'out'?

Richard

[Laurie61]

Lambda 10, very nice. It looks like the mirror may have been refigured  to an A spec given the new s/n ? Mine has year of manufacture and fl engraved on the back and other details were marked in pencil, unfortunately the pencil marks have disappeared over time.

[RLWP]

I've just noticed, your mirror cell isn't a complete ring, it is in three segments

Richard

[Laurie61]

Ideally you will need to work out where your eyepieces come to focus and adjust the focuser travel (in/out) to suit, not all eyepieces come to focus at the same distance from side of tube. You could move the primary a bit if its needed but I doubt you will need to do this. 

[Laurie61]

I've just noticed, your mirror cell isn't a complete ring, it is in three segments

Richard

Yes, that is the original design, I have not modified it. 

[Paul M]

Yes, that is the original design, I have not modified it. 

And it's identical in design to my 6.25 mirror cell. I didn't mod mine either

[RLWP]

I was just observing the variations in Fullerscope parts.

I do notice that the cast ring on mine has several air bubbles in it. Such a shape isn't very easy to cast - there's always a place where the poured metal, having flowed around the ring, meets the flow coming the other way. This is where bubbles, globs, gaps and nasty inclusions happen.

The three legged design you have would cast more reliably

Richard