Would a Cart for a Dob Be a Bad Idea?

[rabbithutch]

Having just got an 8" Dobsonian, I'm a bit overwhelmed by its size. I have a very, very limited patch of sky to look at because of trees and buildings; so it's very likely that I'm going to be lugging it to better sites. Because I'm 69 and have experienced cardiac problems (and well overweight - Hey, Im American - and out of shape), I don't look forward to trudging with a heavy base and a bulky OTA across dark fields: so I had the idea of building a 2-wheeled cart to move it around on. What I need is opinion on whether his could damage the scope.

My plan is to build a square base and have the dob mount sit in it. The dob will sit on its gimbels on the base. It will remain in the cart when viewing and when the scope is stored. Of course, the scope will ride in the cart with the upper end of the OTA pointing more or less skyward as it is wheeled across ground. I can use SketchUp to work out a design that will ensure proper dimensions that will allow the lower end of the OTA to swing as far out as need be for the lowest declination viewing and for the base to rotate as needed.

I don't know enough about the scope to know if this type of rig will do any damage. I have the tools and knowledge to construct the cart, but need to know if the idea is flawed. I think that the scope is LESS likely to be damaged riding in a cart than if I tote it around, but what do I know?

If anyone has already done this and you can point me to an article, I would very much appreciate that, too.

TIA

bob, uncle to dozens

[GrizzlyBear]

I have seen many use carts to lug thier scopes around. I doubt that it would harm it if done properly. Draw something up and get opinion here. it would probably be the best.

[Orion_the_Hunter]

Hi Bob, great idea. A Dob is one of my options, but I would need to build some kind of table/platform to raise it up by about 30-40cm to use on my balcony.

Whilst you are building it, could you post pics of the project?

Cheers, Ed

[ollypenrice]

Lots of Dob owners use a wheelbarrow handle principle. http://images.search.yahoo.com/images/view?back=http%3A%2F%2Fimages.search.yahoo.com%2Fsearch%2Fimages%3Fp%3Ddobsonian%2Bwheelbarrow%2Bhandles%26ei%3DUTF-8%26fr%3Dslv8-grpj%26fr2%3Dtab-web&w=320&h=480&imgurl=www.eyetotheuniverse.com%2FDob%2520in%2520Daylight.jpg&rurl=http%3A%2F%2Fwww.eyetotheuniverse.com%2Fmyastrokit.htm&size=212KB&name=16inch+Dobsonian...&p=dobsonian+wheelbarrow+handles&oid=c1d03b1a9a6d6249fb22a83386281bbf&fr2=tab-web&no=7&tt=15&sigr=11etin0ua&sigi=11gbfgc6s&sigb=13edor1dd&.crumb=y0OgbUh4Rlk

My own big dob used to have two bars with inflatable tyres/wheels on one end. These bars attached to the scope by wing nuts, you picked up the handle ends and walked.

But for yours could you not use a hand truck? One of those thngs used by porters for carrying piles of crates, several suitcases etc? You might make a dedicated base for it. I did this to wheel my 20 inch SCT out into the garden before building fixed observatories. There are ideas for this in Phil Harrington's Star Ware book. http://www.cpsc.gov/cpscpub/prerel/prhtml01/01203a.jpg

Olly

[bcfcciderhead]

What about collimation? would riding on a cart with all the bumps knock it out?

I ask this because if i use my dob in the garden it stays fine, but when i put it in the car and go to a dark site it's out when i check it back at home.

[yeti monster]

I've been considering such a cart. If the scope can be suspended in such a way that shocks are absorbed before they reach the OTA, I think it is an excellent way to lug a beast of a scope around. Perhaps fairly large tyres, inflated to around 10 psi or so might be sufficient to isolate it?

[Peter Drew]

As Yeti suggests, don't skimp on wheel/tyre sizes, within reason the larger wheels are easier to push and ride the bumps better. Design in some cart to ground stabilisers to steady the scope. Good luck and don't overdo the physical. .