Anonymous
Unregistered
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OK guys, here goes:
I am relatively new to astronomy (coming up on year now), but in many ways it just feels like something I've always known I'd get into but just didn't have the time to do so previously. A question posed by the wife as to whether or not we should get a telescope for our son has turned into a mild obsession for me (and I never do anything half way). I'm at least happy to report that the 9 year old son enjoys the nights with the astronomy club as well - particularly when he can point the "red dot" at things and nail them in the sight!
But here's my challenge: The wife and her best friend have purchased a camper-trailer and intend to travel the western U.S. next summer with the four kids. The husbands (that would include me) are to join them for a couple of weeks, likely in the Grand Titons... so naturally, I'm thinking, "I have got to bring a scope."
At present, I have a home-built (purchased) 10" f6 dob, lots of plywood, lots of sonotube, very stable and very wonderful but also awfully heavy and not very transportable. No way this thing is getting to the Grand Titons. Now Jack (my son) likes building stuff goo, so I'm thinking, hey, why not build a truss dob? I bought this scope primarily for the quality of its mirror - I've got a 10" Zambuto here, and a growing collection of quality eypieces, so I'm thinking it's absolutely worth the effort.
Now, I've got a table saw and have enjoyed construction projects in the past, am somewhat of a perfectionist, and would likely have a lot of fun with my son "helping out" here an there. My best friend is a machinest, and I'm sure would love make a contribution as well. So my question is, is it reasonable to think I could get this thing on a plane next summer? The mirror would need to be a carry-on in some fashion, a larger piece could could in the airline cargo-hold, and if necessary the girls could haul something that didn't take up a lot of space across country (poles?)
The positive by-product of all this would be a more light-weight telescope that'd be easy to transport in the car - though I wouldn't want to lose a whole lot of stability in the process - hand-tracking is hard enough as it is.
Let me know what you think, and if you have any recommended designs or ideas that would apply to my constraints.
Contemplating the possibilities, with respect to all who have gone before,
Doug Fults
Edited by MMICKELS (06/01/05 09:21 PM)
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Lawrence Sayre
Post Laureate
Reged: 10/16/04
Posts: 3699
Loc: N.E. Ohio
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This might be what you're looking for:
http://www.fortunecity.com/greenfield/twyford/637/travelscope/travel.scope.htm
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My philosophy, in essence, is the concept of man as a moral being, with his own happiness as the moral purpose of his life, with productive achievement as his noblest activity, and reason as his only absolute.
Ayn Rand (in the appendix to 'Atlas Shrugged')
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tishovlin
Carpal Tunnel
Reged: 11/11/03
Posts: 1812
Loc: Springfield, Pa
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Lawrence,
Is that your scope? I noticed the mirror had been refigured by John Hall. Mine just got done by John as well. I tried to e-mail the author of the report but it would not go thru.
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Tim S
C6-RGT
13.1" Truss Dob
Osypowski dual-axis Eq. Platform
15x70 Obies
NP-101
Gibraltar tripod/mount
Losmandy G-11 w/Gemini
I'm headin for Galt's Gulch
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Lawrence Sayre
Post Laureate
Reged: 10/16/04
Posts: 3699
Loc: N.E. Ohio
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No, not mine. I just found it on the web, and it seemed applicable to the original posters quest. My scope is a Truss Dob more in line with the old classical Kreige Truss Dob concept, and my 13.1" f/5.23 mirror is also self made. Mine is nowhere near as radical as the one I pointed Doug to. Mine is knock-down transportable (as in lugable, since it is not a lightweight), but not suitcase like in any concept of the imagination.
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My philosophy, in essence, is the concept of man as a moral being, with his own happiness as the moral purpose of his life, with productive achievement as his noblest activity, and reason as his only absolute.
Ayn Rand (in the appendix to 'Atlas Shrugged')
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MMICKELS
Aluminum Knight
Reged: 01/20/04
Posts: 25172
Loc: The Land of Shake and Bake
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Doug, I have thought of doing something similar with an 8" mirror.I haven't had the time or money to get to it yet though. I'm looking forward to following your progress!
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Mark
"The only thing wrong with immortality is that it tends to go on forever."
Herb Caen
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Tom L
Reged: 01/07/04
Posts: 29817
Loc: Sunny Oregon
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I would say find a pelican case that you think is large enough to carry your Dob and design the scope to fit within it. I would then study Mark's design and go from there. Good luck.
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Tom 
Tele Vue 102mm f/8.6 on an EzTouch
Vixen 80mm f/5 A80SSWT on a grab-n-go mount
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MMICKELS
Aluminum Knight
Reged: 01/20/04
Posts: 25172
Loc: The Land of Shake and Bake
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Tom, I don't have a design for the eight yet. Ron Boe had some very good ideas though. I want to do the EQ platform first. Too many projects and too little time for me I'm afraid.
Doug I think the challenge is not only to make the thing small and light, but also minimize the number of parts and keep set up to a minimum. You having a machinist friend may prove to be very helpful in the end. Good luck to you.
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Mark
"The only thing wrong with immortality is that it tends to go on forever."
Herb Caen
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Anonymous
Unregistered
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Hey Doug -
There are a lot of choices for a travel scope and they all have trade-offs. I choose a string scope for my travel scope.
I live in San Jose and occasionally bring this scope to Hogue Park if you want to see it in person.
Another option is to go with a traditional dob, but make the mirror box so that the UTA fits inside the mirror box for transport. You then end up with a single box plus poles for transport. The trade-off is that the mirror box ends up being bigger than it my otherwise be.
Here are some links to some examples
Travel scope #1
I almost made one like this
Another 10" travel scope
Portable 12.5" Funky 8" travel scope
Hope this helps.
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Anonymous
Unregistered
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Hey, guys, thanks for all the suggestions! You've given me an awful lot to think about - I had no idea there were so many possible directions to take. Wow.
Craig, that's a real beauty you've got there. Let me know next time you're planning to head to Hogue Park with it as I would love to see it in person!
Steve Vegos's "Another 10" travel scope" looks really promising as well. I'm really curious how he did the counterweighting to gain such a low profile so as to "comply as carry on luggage", and wondering if this would be at all possible to pull off at a longer f6.
Other stuff I've seen, for the benefit of others looking to get ideas:
Starbuckets designs: http://www.starbuckets.com/telescopes.html
Albert Highes:
http://pw2.netcom.com/~ahighe/astroequ.html
Regarding airline-ability, I'm gathering now it's either got to be small enough to be able to carry on key components, or it should fit in a pelican case to tolerate rough cargo-handling (though I don't think I'd ever feel comfortable seeing my mirror on the conveyer belt). I could easily have two sets of tubes though, one set for home & one set for the camper trailer, so at least that would help.
Hmmm. BEFORE the girls' camping trip, my goals had been (1) retain usability as my primary scope (2) compact for car travel and (2) fun (my design tinkering lead to a truss-tube design with a clipped-corner triange base, ornamental rockers and whimsical secondary cutouts  While I'd still love to do this, I suspect it'd be too heavy and large for airline duty.
There are other ways to be fun that wouldn't involve as much weight, but I'm wondering if the compromises required to get in onto a plane would relegate it to "travel scope" status only - and I'd really prefer to keep this as my "primary" scope.
OK, 'nuf for now.
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Tom L
Reged: 01/07/04
Posts: 29817
Loc: Sunny Oregon
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Preliminary design is the funnest part! My scope is based off of Albert Highe's design with my own modifications. Albert is more than willing to help you with design issues and is an email away.
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Tom
Tele Vue 102mm f/8.6 on an EzTouch
Vixen 80mm f/5 A80SSWT on a grab-n-go mount
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Anonymous
Unregistered
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Quote:
Preliminary design is the funnest part! My scope is based off of Albert Highe's design with my own modifications. Albert is more than willing to help you with design issues and is an email away.
Albert is very helpful. He lives in Northern CA so you can frequently see him at the local dark sites. At CalStar last week he had his latest scope made out of paper that was beautiful. It was a 12.5" scope which I believe he said weighed 46 lbs.
Michelle Stone who builds and sells Albert Highe designs is also quite often at the local dark sites and she is very willing to lend advice on scope building. So if you do decide to go with an Albert Highe design I would definitely talk to Michelle (she occasionally posts here as well).
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Tom L
Reged: 01/07/04
Posts: 29817
Loc: Sunny Oregon
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That's very true, I have emailed with Michelle also and she knows her stuff and is more than happy to help answer questions. For some reason, this community of builders is an awesome bunch. I'm not adding anything new with my scope design, but the folks in the business are happy to help.
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Tom
Tele Vue 102mm f/8.6 on an EzTouch
Vixen 80mm f/5 A80SSWT on a grab-n-go mount
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Anonymous
Unregistered
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Preliminaary design is fun OK, I've decided on my design constraints:
(1) Easily portable, meaning e.z. to move outside the garage for quick viewing at night, able to fit into a single seat of a car, and able to be taken on flights with all optics in carry-on components.
(2) Very stable, suitable for use as a primary scope.
(3) Unique and Fun! I'd like this to be the scope the kids run up to at a public night just 'cuz of the way it looks.
OK, with all that in mind, and after perusing the wonderful web, I've started to settle on a design, and in fact have drafted a conceptual diagram, but am not quite set up yet to post it.
To describe it, from the bottom up:
With an f6 mirror, I want a really wide base and wider than typical connect points for the lower portion of the supports. I think something modeled after the low-profile & ultralight double-rings of Greg Babcock's "Ultralight" would be supurb, and could be made very wide and yet still be packed into a travel bag (provided the rocker arm supports are no more than a couple of inches high). Such a low-profile design would require additional weight or possibly springs - at 10", I wouldn't expect plain old lead weights to be that unreasonable, actually. If they have to be hand-held, I'd use scuba weights which are wrapped in plastic.
Having thus dispensed with the rocker box, in favor of stubby supports for the rockers, we'll need big rockers to help compensate. No problem - I love big rockers, think this is a great place for some really cool design work. I'm thinking 20" diameter. These can lie flat in the travel bag as well. To keep everything stable, I'll put a 2" tube between them at the furthest point from the mirror box.
For the mirror box itself, I couldn't help but notice the little box that StarMaster uses to transport the mirrors - and I'm thinking, hey, why not just use that as the mirror box? I'll jsut beef up the carrier box and attach it directly to the rocker arms. Dimensions 4" high by 14" wide and under 22" long - small enough for "carry on" even with a 5" "hat box" for the secondary on top. The extra width of 22" both increases the base for stability and would allow 3 1/2" holes to stuff counter-balance weights into.
The "hat box" would be a 5" piece of 14" sonotube into which the secondary would go (agreed, that will be a bit of a challenge, and require a light shroud, but that can go in the garment bag also). One end of the sonotube would have an 11 1/2" round cover which would also fit both the secondary itself and the primary mirror hole. The other end would be a flat panel which is removed to get out the secondary. the "hat box" itself would be attached to the mirror box as a light shround.
I'll go with a 6 truss-tube design, with 2 of the attachment points at the corners of the mirror boxes nearest the sky when aimed at the horizon, and the third smack in the middle of the 2" connector tube between the rockers (that'll be one of the tougher design aspect, I imagine).
Woo hoo! This is fun. Any suggestions on where to post pictures so as to be able to point at the URL? I'd like to post the conceptual diagram... I could bring my web-server back up, but that might take awhile...
Doug "I don't even know what questions to ask yet..."
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Tom L
Reged: 01/07/04
Posts: 29817
Loc: Sunny Oregon
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Post 'em right here...just keep each picture under 60K and 800x600 or less. I need a picture after that description! Whew!
Honestly, why carry the mirror? Pack it within an inch of it's life and don't worry about it. If you design the packaging as part of the overall design, you can do it in such a way that a gorilla would have to take it out of it's case and drop it in order to hurt it.
Looking forward to seeing the drawings.
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Tom
Tele Vue 102mm f/8.6 on an EzTouch
Vixen 80mm f/5 A80SSWT on a grab-n-go mount
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Anonymous
Unregistered
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Ok,the "Instant" BBB Code is not helping... let's try "preview and post and/or attach a file"
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Anonymous
Unregistered
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Hey, it worked! Ok, here's one more, just a design element from a previous effort I'd like to work in if possible.
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Tom L
Reged: 01/07/04
Posts: 29817
Loc: Sunny Oregon
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Your design is very cool looking. Your center of gravity will need to be really low and offset for your bearings to be that low and positioned that far forward. How heavy is your mirror and how many weights are you planning to add? The weights will have to be added to the front...you could always house a small battery there instead and run dew heaters, fans and blinking red LEDs (  ) to gain that extra weight.
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Tom
Tele Vue 102mm f/8.6 on an EzTouch
Vixen 80mm f/5 A80SSWT on a grab-n-go mount
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Anonymous
Unregistered
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I've not had the mirror out of the current scope yet, so I actually don't know yet how much the mirror weighs! I'm guessing that this design will require a *lot* of extra weight though (or springs) - if all goes well the CG is still only some 9" from the pivot point, which gives me only a 1:5 or so leverage arm over the secondary. I like the battery idea! but blinking LEDs??? As for the offset I actually hadn't intended that originally (as I'd wanted it centered between the pole attachment points), but do see how it crept in at the last moment. I might try reducing the width of the mirror box to only 12"x20"-ish so that the 14" tube can overlap on both sides, which would eliminate the offset.
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Tom L
Reged: 01/07/04
Posts: 29817
Loc: Sunny Oregon
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Quote:
...but blinking LEDs???
It was a joke...you said you wanted a scope that all the 10yo boys would flock to at star parties. Having boys of my own, I know how much they like blinking red lights! Actually, placing the battery in front of the mirror box and making it part of it will shift your CG to a more appropriate location as depicted in your initial drawing. This design is cool looking...I hope you take my comments as just food for thought.
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Tom
Tele Vue 102mm f/8.6 on an EzTouch
Vixen 80mm f/5 A80SSWT on a grab-n-go mount
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Anonymous
Unregistered
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Quote:
Quote:
...but blinking LEDs???
It was a joke...you said you wanted a scope that all the 10yo boys would flock to at star parties. Having boys of my own, I know how much they like blinking red lights!
Good point! 
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