ATMers - Show us your home-built telescope

[Omaroo]

ATM is alive and well in Oz it seems. There are plenty of people designing, building and using their own reflectors and refractors.

Let's see a photo or two of your own amateur construction effort, all here in the one thread. We didn't have one going, so I thought I'd throw one up.

:atom:

[Omaroo]

My first refractor assemblage - using a short length of poly pipe, an Meade SCT visual back - interference fit into the tube. A WO SCT focuser attaches to that. The business end is a SuplusShed 80x400mm objective pre-mounted in a cell. I've used three short tech screws to hold the objective on to the tube. Length of the tube was determined by lying all the components along a board which I then aimed at a very distant object, and moved the pieces around until I thought I had focus. I measured the distance between the end of the cell and the back of the SCT visual back to determine the tube length.

It is not able to be collimated, which is a pity, but it is still pretty sharp. I have flocked the tube with self-adhesive flocking paper to keep internal reflections off the otherwise white tube to a minimum. I've also attached a Vixen-style dovetail by using short countersunk bolts and bolting straight through into the tube. The nuts and end of the bolts on the inside are not long enough to enter the light path. I've also mounted a WO red dot finder.

Views are good - but being achromatic the scope suffers typical colour - which is virtually cancelled with a minus violet filter on all but the brightest objects (Sirius, etc).

The stainless steel object on the end of the objective cell is the cover off a thermos flask's cup - and is used as a cap, not a dew shield. I plan to make a dew heater to combat the obvious.

[Glenhuon]

Received the package this morning, so got right into it. :)
Did a bit of searching around town for suitable pipe, but nothing available apart from truck exhaust pipe (too heavy) so settled for 100mm PVC.
Its 1mm too big in OD, but an hours work with a coarse file and some emery cloth brought it down to size.
The objective has 3 screw holes for holding it in place, beware, they are not evenly spaced. If you drill through, mark one hole and the tube so it goes back the same way if you remove it.

Turned next to the focuser. Its spigot diameter is 95mm so had to bush the inside of the tube down to suit. The Pad Repair Fitting to the rescue again. These fittings are tapered inside and out. I cut it off at the shoulder and found that the ID at that end was narrower. It also wasn't a real tight fit inside the 100mm. As you can see in the pic I cut right through it lengthwise, the focuser spigot slipped inside and it expanded the OD enough to make it a snug fit in the tube. The focuser spigot has 3x4mm tapped holes in it so marked them driled and fitted 3 salvaged screws to hold it in place.

Tube was initially cut purposely too long, lots of taking off tools here, not many puter oners :)
Tried it with only eyepiece, too long, cut of 100mm. OK
Tried with 2" diagonal. too long, cut off 80mm.

Dust cover is off a 50 pack of CD's, perfect fit.

Made rings from 100mm pipeclips, used the redundant plate from the 80mm to mount it up and ready for first light :D

Tube has still to be flocked inside, fine tuning of length and find something for a dew shield, but essentially all done.

Time taken 8 hours, including running around looking for "bits that fit".

Yes, I'm tired :lol:

Bill

[PhilW]

Great scope Bill! Looks like that PVC tube really works well.

OK, since Chris asked, here is my main scope. I took the light shrouds off for clarity in the photos. Key features are:
- 35cm F/4.6 Suchting mirror
- Mirror box is a ply/foam board/fibreglass resin composite structure, lined with the ProtoStar flocking material
- It has a cooling fan in the back, suspended with 'scrunchies' (= elastic hair ties from the $2 shop), so vibration does not transmit to the scope
- Cell is a 6-pointer designed with PLOP
- Now has Dave Ek's encoder system fitted (that's the disk & wires on the side)
- Six-tube truss; the tubes are bolted together, so they stay together as a unit when you disassemble it (three nuts top & bottom)
- Wire spider made from a 0.016" guitar string. It tensions up with wingnuts, one of which is just visible in the photo
- Filter slide; has a click stop made from a bathroom cupboard catch
- UTA has foam board in place of kydex. Total weight of the UTA is 2.2kg (it's designed for wimps, i.e. me). :whistle:

It balances with eyepieces around 500g. If I use very light eyepieces I have to hang a weight on the front.

Phil

[Glenhuon]

Excellent job Phil. I like the guitar string spider :)

Bill

[stringscope]

Been posted before but here is my 8" F5 fo F16 refractor on alt/az mount. Hoop-pine ply with Oregon legs.

[tnott]

Most of you have probably seen my scope in the articles section but I'll post it here again. The top end now has been reinforced with aluminium tubing bent into a ring (not seen in the picture) to stop the secondary from moving from horizon to zenith. I have also added a drive but I am still waiting for some software issues to be sorted out for it to work.

[stringscope]

Also been seen before. 8" F6 String Truss Travel Scope - Complete observing package.

Ice-scope was at Wiruna last winter.

[Omaroo]

Fantastic job Bill :) Another keeper?

[Glenhuon]

Just had first light, focuses with all eyepieces and diagonal, perfect Aerey rings on the star test, definitely a keeper Chris :)

Just had a funny thought. When I was working I spent my days looking down sewer pipes, now I spend my nights looking up them. :lol:

Bill

[gbeal]

Not much to see picture wise as I didn't do the step by step thing. Plus it is like most any other truss newt.
The new 16" f4.5, to "replace/supplement" the good old 10".
Built between November last year and January this. Truss shroud is a work in progress, mainly catching the Chief Sewing Officer on the machine.
Gary

[Alchemy]

sorry ive only ever bought stuff or paid someone else to do it.

i just want to post to say how impressed i am with the work you guys have done.... amazing!

[Omaroo]

Ian - both of yours are wonderful :) I musy have missed mention of it before - but your refractor has adjustable ratios - f/5 to f/16? I notice the helical objective mount - so how do you change the f/length in relation to its diameter? Are you moving a flint & crown in relation to each other or something?

[Omaroo]

Tim - I love your rocker box. I'm thinking of using its overall design to base my binocular on. I have already made the basic rocker box and it's very shallow too. I like the bearing extensions on yours - similar to the new Obsession ultralight. Do you have any close-ups of the box/bearing design?

[Glenhuon]

What an array of wonderful inovative instruments ! I salute you all :thumbsup:

Bill

[stringscope]

Hi Chris,

The objective lens system is actually the optics from an ex NASA satellite tracking camera. "MOTS". There appear to be 6 or more elements contained within the 500mm long lens cell. In the centre of the cell is an adjustable iris diaphram just like a normal camera lens - just that this one is on steroids. The objective cell is 220mm diameter, 500mm long and weighs 26kg if I recall correctly. Mounting it was a significant exercise. I have attached some additional images that hopefully show how it works. The whole scope weighs more than my 407mm F4.5 Dob!!

While it was designed to deliver a 200mm diameter flat and orthoscopic photographic image, it is not much as a visual instrument and I don't use it. Great fun to build though :D .

In order the images are:
Objective cell prior to mounting after I had fitted some mounting rings to firtinside a 250mm diameter tube.
Next 2 from the front showing iris partly closed and fully open.
F/Ratio Change Knob below focuser F5 - F16.
F/Ratio change drive gear.
Internal collimatable diaginal mirror.

Cheers,

[Omaroo]

How cool is that? Thanks for showing it Ian! Very interesting indeed :)

[GrahamL]

good idea chris :)...nice looking scopes guys a couple I hadn't noticed before :thumbsup:..I not long did mine and its still currant on this page a few posts down so more pics of the same seems a little overboard .
heres a finished pic .. [strange I was hopeing to remove this pic from its original post but can't seem to edit that thread ?]

more here
http://www.iceinspace.com.au/forum/showthread.php?t=21096

Its has a 12 f5 gso primary
2.6" protostar pyrex secondary and 4 vane spider.
kineoptics hc 2 focuser
moonlite connecters top and bottom
And a homebrew velcro mounted mirror cell

[Glenhuon]

Just an Adendum to the 102x900.
Painted the tube to day, inside Black, Outside White.
A word of caution to those who have not used it before.
When painting PVC the tube has to be cleaned inside and out with PVC primer or the paint will flake off due to the release agent used in the manufacture of the tube. Hence the pink colour.
This liquid is composed mainly of Methyl Ethyl Keytone. This is nasty stuff. Use it outside, don't breath the fumes and don't get it on your skin (use gloves and eye protection). Its safe if you follow the rules, but otherwise......

Bill

[Rod]

Here are some pictures of my 12 inch F5 telescope. I made the mirror several years ago and originally had it in a very heavy mount that I rarely used. The current mount is a 'flex rocker' designed to be compact and light - and gets used regularly. The mirror sits on a 4 point mirror cell which can be adjusted by two collimation knobs located at the front of the mirror box. Like Phil's the secondary is supported by a wire spider.

It's great to see everyone's instruments on one thread.

Rod.

[Rod]

Ian,

I love your stringscope especially the way it folds down to that box. What are the strings made of (Kevlar?) and where did you get them from?

Thanks,

Rod.

[stringscope]

Hi Rod,

The strings are "Plus 450" Archery Bow String acquired from a local archery shop. Comes in a reel, quite expensive $100/reel if I remember. Also need a reel of serving thread and you need to learn how to "serve" the ends. The thread below covers the construction of this beastie.

http://www.iceinspace.com.au/forum/showthread.php?t=1562&highlight=stringscope

Cheers,

[Rod]

Thanks Ian,

I had a look at the thread. Very nice work!

Rod.

[tnott]

Here are some closeups of the flex rocker plus pics of the reinforced top ring. For more info on flex rockers check out Mel Bartels' site, esp. the section on the trilateral mount:

http://www.bbastrodesigns.com/

BTW the Tridob uses a rigid ground ring and 'flex-rocker' rather than a rigid rocker box and thin ground board like many designs. My current work in progress is a F3.6 22" version of the Obsession UC.:)

[GaryF]

I'm a little out of town so hope it's okay to post in this thread...

Here's a link and a shot of my 105mm f27 DelMarva Schiefspiegler at our Stellafane convention. It's mostly made from scrap yard bits and pieces.

http://stellafane.org/convention/2007/images/scopes/Entry19/P8112729.JPG

In the attached photo the scope's designer's (David Groski) Schupmann is to the right.

Regards,

Gary Fuchs
Pennsylvania, USA

[gbeal]

Welcome to the forum down under Gary. Good to see some weird (and I mean that in the nicest way) scopes appearing. Man I can't even pronounce the name, let alone spell it.
Gary

[GaryF]

Thanks Gary!

It is a bit weird and hard to pronounce and locating targets with the tight FOV without a finder is tricky...but, with the 2700mm focal length I get about 100X with a 26mm eyepiece, 150X with an 18mm, and it can handle 225X with a 12mm - maybe more if I could get skies like you guys have...

Also all spherical optics so no need for parabolizing; and a contrasty and colorfree view with no obstruction and long eyerelief. Not exactly a rich-field scope but I can just squeeze the moon in with a 2" 30mm wide angle ep.

Gary

[Glenhuon]

Great unususal scope design Gary. Looks like I'd have to go get an engineering degree to operate it though :lol:

Bill

[GaryF]

Bill,

"Looks like I'd have to go get an engineering degree to operate it "

Not at all! In use (with a finder!) it feels like a refractor. Collimation is simple: laser in the focuser, center dot on round secondary, adjust secondary to hit center of primary and adjust primary to hit a point a certain distance above the secondary. I use a piece of aluminum held with a rubber band for a target.

The other thing to get used to is the very narrow field. With the high native magnification I think a tracking mount is called for - but even the simple one I have is sufficient. There's a fairly broad range for focus too.

Over here a lot of ATMs are engineers or have tech backgrounds. I don't (though I do tinker a lot and am fairly handy) and was able to build this and get the angles right without any major problems - there are basically two or three measurements that constrain eveything else. The mirrors weren't hard to make but I wouldn't recommend them for your first attempt. The two have to be as nearly identical in radius as possible - but convex and concave and that's maybe a little tougher than it might seem. You test the primary by nulling Foucault - no masks or calculations, and the secondary by interference against the primary. Nothing fancy needed for that - you can use a piece of green or red cellophane and a flourescent light. Also, working glass that small and thin with normal or even smallish hands and keeping your fingers off the front isn't one half as hard as a 200mm as some suggest who haven't tried it! Having said that, I believe it could be done by a first timer with patience.

I guess I'm excited about it because it performs so well and was inexpensive to make. The inexpensive part is very important to me!

Here's a handheld shot at 150X from a few days ago. It doesn't begin to do justice to the real view.

Cheers,

Gary

[Glenhuon]

I was only joking, looks really well constructed. I'm a retired Mech Fitter so can appreciate the work that went into it.
Never got into grinding optics.. yet. Might give it a go one day.
The inexpensive appeals to me too :lol:
Nice pic, wish I could get a handheld with mine like that :)

Cheers
Bill

[stringscope]

Hi Gary,

:welcome: to IIS. I followed the construction of your Schief over on CN.

Really nicely done including the focuser unit :thumbsup:.

I dream of building one, ............. one day :whistle:

Cheers,

[dugnsuz]

Holy Foccacia,
You guys are an innovative and resourceful lot aren't you!!!!????
Absolutely great
Doug

[Glenhuon]

102 completed :D Now all I need is for the rain to stop and the clouds to go away.

Bill

[Omaroo]

Beautiful Bill! Another masterpiece.

[Starkler]

Certainly looks the goods Bill :thumbsup:
Does it have baffling inside?

[Glenhuon]

No baffling, seems ok without it since I painted the inside black. Just found a perfect fit dust cover for the dew shield, the base of the Fereo Rocher "Bell" I bought Kym for Valentines Day. Someone is looking after me :)
Spent most of the day making the dew shield, that colourbond is springy stuff. Had to bend it around a 100mm pipe to get the initial curve, grind off the paint and zinc coating on the first 12mm of the overlap before it would take a silver solder weld, then squeeze and push it into a tube shape with me thumbs. Gee, I miss the tools that were available when I was working, could have knocked it off in an hour or so. :lol:

Bill

[GaryF]

Bill, Ian, et al,

I don't want to hijack this thread any more than I already have but I'd be happy to provide more info and/or connect you with the scope's designer. Just PM me...

Regards,

Gary

[Glenhuon]

Just a quick one of the Moon. Ready for a good nights sleep :)

Bill

[DaveGee]

two scopes...
here's my 10"f5 Newtonian on my home made GEM with GOTO

and my 7"f7 Dob

[snowyskiesau]

That mount looks quite different to the one described on your website.
Any construction photos for budding machinists? :)

[DaveGee]

Sure, the pictures on my site are fairly old and the whole site needs updating.

The old motors and drives were removed and replaced with new 190:1 boxes and new steppers all controlled be Mel Bartels scope.exe GOTO software. It all works fine however the steppers are a bit noisy and I wish I'd heeded the tips on Mel's site re. rubber isolating the motor housing. Oh well another project to add to the list.

here's some pictures of the gearbox innards ect ect...

[tempestwizz]

Here's my first attempt at a Dob. 12.5" F5 . It rotates (RA) on a ground ring, and in Dec, the rings sit on bearings on one side and teflon skids on the other. Is very smooth to operate.
I'm currently building a new 10" version.
There's certainly a lot of interesting designs out there.

Brian

[Omaroo]

Brilliant Dave.

I wish I could go back 20 years and use the workshop my father maintained while my brother and I were kids. We had access to a 36" lathe, a Myford ML7 and a Unimat 3. We also had a CNC milling platform and plenty of other great stuff in the workshop.

I would just love to build a mount like you have. I've looked long and hard at the G-11 and reckon that there's nothing hard to duplicate.

Hmmm... maybe one day.

Very well done! :thumbsup:

[Glenhuon]

Yep, it looks great. I miss the facilities I had when working for the Water Corp too.
Just joined the local "Mens Shed". Mostly into wood working, lots of machine and hand tools. First project already started, a denver observing chair. Not a great deal of metal working gear there, but they do have a little myford style lathe with a mill head attachment. Can think of lots of uses for that :)

Bill

[Omaroo]

"Mens Shed"? Sounds interesting Bill - might have to investigate!

By the way - that workshop was in our garage... and I didn't even think of buying all the gear off my father when he retired and moved to Brisbane! D'oh! :doh:

[asterisk]

Hi Chris

Mens Shed:

"Every community in Australia will have a men’s shed.
<LI style="COLOR: rgb(51,51,51)">To address the issues of men’s health (physical, emotional and social well-being) in the community. <LI style="COLOR: rgb(51,51,51)">To engage the elderly, differently-abled, youth, veterans and other groups of men of the communities in both rural Australia and urban Australia, and to specifically address any issues of isolation, loneliness and depression; <LI style="COLOR: rgb(51,51,51)">To support the social interaction of men in transitional periods (e.g. Redundancy, Bereavement, Retirement, Ill Health, Relocation, Respite Care);
To share, disseminate and preserve the skills, abilities and interests that are relevant to the community. "None local.

Good luck

[Glenhuon]

The Shed here in Coota has been going since about 1996, just completed a major extension which was officially opened last Wednesday. We had quite a few visitors from other sheds in surrounding towns interested to find out about expanding their places or starting one. Its a great way of sharing resources and knowledge, keeps guys active in retirement, and in one case I know got a bloke who had lost a lower limb an interest outside home. The president reckons he's even had wives come to him about asking their hubby's to join the shed, and get them out from under their feet for a while :lol:

Bill

[anj026]

This is an interesting thread, thanks everyone for sharing pictures.

Here is picture of a 6"f5 dob I made a while back using a Meade mirror. The tube is octagonal 4mm ply. I sold this scope. It was very light and great for casual stargazing.

The refractor is 6"f15, also octagonal tube made with 4mm ply. The lens is made by D&G. I wrote a review that you can read here at Ice in Space. It is not the most convenient scope to use but the views are worth it.

[Glenhuon]

Nice woodwork Andy, theres something about a wooden scope that is very appealing.
The 6" refractor reminds me of the ones shown in prints of Astronomers of yesteryear. Can just picture someone there at the eyepiece with the long tailed coat and top hat :)

Bill

[anj026]

Thanks Bill.
I admit the woodwork is a big part of the fun for me. I love to dream and plan new telescopes. Very few actually get built but I've always been a bit of a dreamer. I love to look through old Sky and Telescope magazines and books like The History of Telescopes by Henry C King. It is very satisfying to create something that can bring the universe closer and can be shared with family and friends.

[Kokatha man]

Just had to make a comment Dave - from someone who loves tinkering and inventing/adapting: your achievemnets (to use a modern expression) just blow me away!

And to think people in their ignorance get worked up over Obsessions and SDM's etc - not to be too derogatory towards suchlike - but your constructions just make that sort of stuff second-rate!

Particularly impressed by the finishes as well as the machining/fabrication and other intricacies: formed ply tubing et al (please don't tell us it's only Bunnings cheapo stick-on faux wood grain and enhanced photos!)

Honestly brother, works of art (and I'm a pro artist) - is that a telephoto camera lens mechanism adapted for the focusser?

Highest quality Dave, regards, Darryl.

[DaveGee]

Hi Darryl,

I guess you mean the focusser on the 7" Dob. Yes it's made from the helical section of a 100mm telephoto lens. I found it at a car boot sale for $2 IIRC.

[Starkler]

I dont think its fair or appropriate to describe people who appreciate obsession or SDM scopes as ignorant :whistle:
You are comparing apples with oranges in so many ways here.

I could say more but I wont....

[Kokatha man]

Hi Geoff - I was tossing up whether to go fishing tonight (the waters in my bay look so darn inviting) but I'd hafta hook up some new nav lights first: decided "sod it!" - we've had such good ob nights without wind that I'll enjoy that instead. But little did I know that I'd left some unintended bait out.....

First up, before I explain my comments, let me apologise for offending you: it was not an intention of mine; but neither is appearing offensive my desire - so I do apologise.

"Ignorance," as in my phrase "people in their ignorance" has no connotation of they being ignorant per se - ie they are not "intrinsically" or "by or in itself" ignorant (Macquarie dictionary) but rather "they" are "ignorant of" something specific - in this case the heights to which technical, as well as aesthetic creativity can rise. It is what is generally referred to as "small i" ignorance.

This is not "snake oil" I am applying Geoff with the above explanation: a simple troll through my posts should evince you of the grammatical focus within my writing; be it the patois of "lingo" or erudite english grammar. This is because of my appreciation, and professional employment of, language.

I have lived a public life or sorts where essays, papers and other written presentations have been a stock-in-trade: you will no doubt have been aware of my post on "Reconciliation," and I would like to assure you that on matters pertaining to that subject I am an optomist as well as a committed (public) worker towards such - it is my belief that many prejudices are based on "small i" ignorance as opposed to deep-seated xenophobic hate et al, providing me with the logic (some might say faith) that these issues may be resolved for the benefit of all.

Seeing Dave Gee's creation (to give it its' proper description in my appraisal) literally "blew me away" - and I would add here Geoff that I am a professional artist with an international reputation who not only has an aesthetic dictate, but by definition has had to attain technical dexterity with many processes; often working alongside architects, engineers et al to accomplish commissions. (google "yerrakartarta" or "yangadlitya" to appreciate the scale and intricacy of some of my "art.")

You are quite right about apples and oranges, it is most probably highly debatable that Dave would even consider making equipment for others: the cost of such a labour of love would be prohibitive. This does not, however, cause me to resile from my belief that his achievements "pale into the shade" the Obsessions and SDM's et al: though of course as commercial products they are constrained by said identity.

Perhaps it would have been more proper for me to use the above comments re my comparisons: this would have alleviated the possibility of it seeming to be personally offensive to you (and other owners of said equipment.)

Once again, I apologise for the unintended slight you perceived; and I'll say with a smile that if one of the fine scopes you and others possess came my way, I'd have a smile a mile wide.

Best regards, Darryl.

[omnivorr]

..Darryl 's usage intended the meaning : "unaware of "

:)

Cheers
Russ PS I too am AWESTRUCK with admiration (and envy), not only at DaveGee's creations,
but at the sheer magic of their material qualities... parts of that mount look like they were sculpted from billet alloy :)

[Starkler]

Thank you Darryl for your rather verbose reply and explanation.

Rather than finding the comment personally offensive, I assumed that perhaps your comment was spawned by a desire to bring the owners of high grade commercial scopes 'down a peg'. Whether such comment can attributed to previous experience with a person bragging of owning such a scope, or envy I do not know. A person getting "worked up" over an obsession or sdm isn't necessarily exclusive of knowledge that something better may exist out there in ATM land.

As an SDM owner, I take absolutely no credit for the quality and workmanship of the scope that I purchased. Apart from my input as to the basic specifications of the scope, all I did was hand over a wad of cash. I give full credit and kudos to skilled ATM people like DaveGee who have turned their skills to producing outstanding work the likes of which simply cannot be purchased commercially.

I really do envy those with the skills, time and tools to be able to do great ATM work. I think we all know that just about all commercially made scopes and mounts leave something to be desired, and the ability to custom make exactly what you want is a wonderful thing.

[Kokatha man]

"I dont think its fair or appropriate to describe people who appreciate obsession or SDM scopes as ignorant :whistle:"



Hi again Geoff - as I hope I articulated, semantics et al are fascinating subjects: and perhaps before I go any further I should confess that I can be a bit of a stirrer (termed "devil's advocate" in more formal surrounds!)

Having made this admission I'll cheekily state I've (obviously) included selected quotes from your postings to stir/suggest that there can be all sorts of (possible) interpretative constructs in "a bunch or words."

Notwithstanding aforesaid, there was definitely no intention to be personally offensive either in fact or perception; I should have chosen my words of praise more carefully - maybe something along the lines of your comment re commercial productions. (though could that perhaps have lead to a "posting assault" on me from every owner of any expensive commercial gear?!?)

My apologies again Geoff for any slight, regards, Darryl.

[AstroJunk]

Darryl,

Never, ever, even on the darkest, gloomiest, rainiest night, ever, coment on a mans choice of telescope.

You might as well just call his wife a minger that sleeps with goats.

Some things you just don't troll about:P

[Kokatha man]

Hi AstroJunk - methinks you've come in a bit late on this current lot of postings for me to get too verbose!

What's a "minger?" - doesn't sound too nice and certainly sexist: perhaps it's something you've experience of, but I'm sure the moderators wouldn't approve?!?

Anyways, I notice you've got one o' dem types of scopes too - I can takes a hint wid d' best o' 'em: mebbe's I should start on Losmandys or Taks jist t' git the balance right!

Regards, Darryl. ps whaddya tink of d' thread sommun started called "who's got the best scope?" or somesuch?!?

[Omaroo]

Uhmm.. I'm sorry, but will you blokes take your argument elsewhere please? I started this thread to let people introduce their home-made equipment, not talk semantics.

[Satchmo]

Yes we need a `Starry night with camp-fire and bottle of Port' section of the forum for this sort of stuff. It would be good if moderaters had a simple `eject to the camp-fire ' button.:lol:

[stringscope]

OK. To get back on track:

16" F.45 String Truss Dob - just operational and first light 8 hrs before leaving for the 2007 SPSP.

Entire instrument designed to fit into the boot of a Holden Astra sedan - and it does too :lol:

Few changes since then. More photos to follow.

Cheers,

[Glenhuon]

Yep :lol:
Quite miss the "Port and Cheese" sessions we used to have at WA astrocamps. Was a good break between observing sessions and helped everyone calm down, relax a bit and remember that the voices in the dark were real people. :)

Bill

[Glenhuon]

It does too :eyepop:should rename the car Tardis.

Bill

[anj026]

Here is my 90mm achromat. It is basically a smaller version of the 6", similar construction. The focuser is a GSO 2 speed with dielectric diagonal. The focuser adapter is homemade from brass. The mount shown is the same one for the 6" refractor just with less counter-weights and a different dovetail clamp and plate. The lens is an Antares 'Vixen spec' traditional style achromat made in Japan, magnesium fluoride coatings on all surfaces, 1500mm focal length. I am in the process of making a portable mount for this scope but young children and study commitments have been taking priority.

[DaveGee]

Very nice Andy,:thumbsup:

Do you have details on the construction of the tube? and where did you acquire the objective? Hmmm wood tubes are nice.;)

[stringscope]

Hi Andy,

I am with David Gee on this. Your scope looks fantastic:bowdown:, I reckon there is something really nice about a wood scope tube :)

I have been wanting to have a go at an octagonal scope tube for some time so if you could offer any hints that would be great.

Cheers,

[anj026]

Hi Guys

The construction is the same principal used for the 6" refractor that is shown in my review of the D&G 6" f15 lens. It uses 4mm marine ply with baffles acting as ring frames. Check out that review and if you have any other questions I will try my best to answer.
I bought the lens online from Hands On Optics in the US. It is listed under accessories; parts; Antares. I paid about $160-170US and feel it is worth it for a quality hand made lens (made in Japan). It is shown as 93/1500 but actually works out to 90mm clear aperture once mounted in a cell. It comes without a cell but Hands On will probably be able to supply one if you ask them. The Antares 4" lens' come with a cell but are $350US. I used one that I purchased from Meridian Telescopes in the US for about $30 and then modified it to suit the wooden tube. If you are handy with a metal lathe the cell should be easy enough to make yourself.

Regards

[Paddy]

Ian, I'm very impressed and as I am interested in the possibility of building a lightweight and compact 18" reflector, I wonder what weights you ended up with and where you got you mirror and plans

[stringscope]

Hi Patrick,

No formal plans I am afraid, lots of inspiration off the web though. Mirror second hand through IIS (20yo Meade), repolished and refigured by Mark Suchting.

Operational weights (kg):

Rocker box 9
Altitude bearings 2.7
Mirror box incl 4X2.2AH SLA batteries
dew heat controller cables etc 25.4 (batts weigh 4 kg total)
UTA 2.8
Finders & misc 1

Weight excl truss 40.9 kg

The scope has 2 truss configurations:
String truss 0.5
Tube truss 2.8

Complete operational max weight excluding eyepiece 43.7 kg

Note: There are no counterweights required or fitted.

Cheers,

[stringscope]

If you are looking for a very light weight design, Stathis 24" scope is most impressive I reckon ;)

http://www.stathis-firstlight.de/atm/

[Kokatha man]

Hi s/scope - I'm rather intrigued by your 8" refractor: you comment that "it is not much as a visual insrutrument and I don't use it" -
could you elaborate a bit on that please, and let me know whether you've used it for any sort of imaging?

I ask, because for nigh on 40 years now, I have possessed a somewhat similar lens assembly that I allways harboured the idea of transforming into a scope of sorts.

Mine is a compound lens assembly, not having disassembled it I don't know the number of lens, but several at least; it has an objective diameter of 6&1/4" with a focal length of 50". (f8) This can be varied, like yours, by an iris diaphragm that is operated via a rotating ring on the lens body.

I had it on excellent authority to have been formerly utilized as a type of telephoto lens by Adelaide's "Advertiser" daily paper by the sports photographer: it originally came mounted onto a long rectangular box that was tripod mounted, the rear end of the box holding a large photographic plate/film. Evidently it had some fame as the camera responsible for some classic football and Test cricket photographs.

It's provenance prior to this was (reputedly) that of being a sophisticated camera lens; part of a speciallized aircraft reconnaissance job. I think, given the era when I bought it (circa 1970) it was more likely to be such than something akin to your lens prior life - satellites only being 14-15 years before it came into my possession. The lens are optically coated, it is quite a heavy assemblage and that is about it.

Have entertained ideas about employing it for some use for many years, and how I've managed to drag it around with me all these years is a minor miracle in itself! Would be interested to hear your thoughts, and if you would elaborate a bit on the question I put to you above.

Regards, Darryl.

[Paddy]

Thanks for the link and the information, Ian. All stored for future reference!

[stringscope]

Hi Darryl,

Compared to a Newtonian of similar aperture, this refractor exhibits significant CA, dimmer image and lower contrast. My primay interest is visual DSO observing and therefore not much use to me.

On the plus side a very flat field and in monochrome light, very sharp indeed.

I had to build a mount for it to find this out. I guess you will have to go through the same process with your lens.

See attached link

http://www.iceinspace.com.au/forum/showthread.php?t=17888

Cheers

[AlexN]

incredible work by everyone who's posted scopes!!

One day off in the future I can see myself with a big fat 16 - 20" truss... Perhaps one day WAY off in the future...

[Roger Davis]

Let's see... When I was 11 I made the 6" f/8 the optics of which I still have. Then the 10" f/9.2 which we used at school. It had three eyepiece ports and the secondary mirror moved around to three detents to make observing easier. Following that there were a few more reflectors of various apertures from 10" to 18". Then I was asked to do a 16" f/4.5 for a guy with low COG. Then I made a couple of front ends for a few dobs and a 20". Then I did the 27" for the ASV along with a couple of other guys (that's a 27" upper cage assembly on my garage wall). Hmm, think that's enough.

[jayscheuerle]

Wow! There are some amazing scopes here that I'm sure will affect my next project's direction. This is the 2nd version of this scope that I'm continuing to tidy up. Everything but the trusses packs into the ball. Thanks for looking! - j

[Omaroo]

Jeepers Jay - that looks fantastic. :thumbsup:

It looks so well put together it could could pass as factory-built. That's a compliment by the way :) Very nicely finished! How much does it weigh?

[jayscheuerle]

Thanks, Chris! I weighed it for the first time tonight and it's around 18.5 lbs. (8.4 kg) assembled, including base. - j

[astronut]

Excellent job Jay,
It's one beautiful looking scope!!.
BTW I haven't recieved the heater yet for the secondary, may be next week!.
John:thumbsup:

[AlexN]

Jay.

Wow!

Speechless.. Perhaps next time a 12" of the same design!

[mental4astro]

I dare to disturb a sleeping dog-> this thread has been dormant for some time. Let's raise it from its slumber of two years and see what happens :poke::scared2::prey2:

I'll add my two much flogged scopes and diy dobbie mounts...

10" f/5 dob
17.5" f/4.5 dob
8" f/4 on diy mount, shared scope with Hickny, :thumbsup:
4.5" on diy mount

[jayscheuerle]

Those are some real scopes, Alexander. I've got a 16" waiting in the wings to start on, but I've been playing small in the mean-time.

There's a couple of sub $100 4.5" f/8s, the ball one being the "PortaBowl". A 4" f/6 beater scope "Frank the Tank". And a 6" f/5 called "Frankenscope".

All good exercises, but I really need to buckle down and make the practical biggie... - j

http://home.comcast.net/~jayscheuerle/stick.jpg
http://home.comcast.net/~jayscheuerle/portabowl.jpg
http://home.comcast.net/~jayscheuerle/frank.jpg
http://home.comcast.net/~jayscheuerle/frankenscope.jpg

[mental4astro]

"Frankenscope", :lol:, that is one seriously stitched up puppy, :lol:. Looks like you've used bits and pieces dug up from some telescope graveyard- isn't that a focuser from an old Astroscan?

I've noticed an RKE eyepiece in another one of your scopes- they are really good eyepieces. I've got an approximately 25 year old 28mm RKE, and it works sooooo well in the 17.5" Odessius.

Jay, lovely work with the Eeor2.

[jayscheuerle]

Not from the Astroscan, but another Edmund 6" f/6(?). - Good call!
Top can, end rings, and finder are cut from some orange Celestron with a broken sled focuser (I bought the mirror, he sent the scope). Bearings are legs from an Ikea table.

Gave it to a teacher friend of mine. Had to ad braces connecting the ends of the bearings to where the trusses connect the upper can because the bearings were like giant kangaroo feet, bouncing the scope all around... - j

[pgc hunter]

wow those are COOL!

[CharlesM]

Hi all, new member here.
Heres an 80mm f15 refractor I built a while ago.
It was supposed to be a quick project using ag pipe but I got totally carried away.
The worst part was all the polishing.

The lens is an 83mm Jaeger (sp?) doublet, all brass and large section aluminium is home cast.
If anyone is interested the full build details can be found here
https://www.hobby-machinist.com/threads/80mm-long-focal-length-refractor.26212/


My latest project is a 12" bino.
Another very long project but its getting closer to the finish if we consider grinding and polishing the two mirrors to be a quick job.
Again the full story is here
https://www.hobby-machinist.com/threads/the-giant-binocular.55688/
I hope to be flexing the mirrors but have a number of questions that I will be asking else where on the forum.

[sopticals]

My current "stable", but need to "thin the herd". Anyone interested in a 25" dob??

Stephen.

[Bobbyoutback]

Wow Stephen !

Respect
Bobby :)

[croweater]

That nice 10" Zhumell would do me Stephen
Cheers, Richard