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Old 01-03-2019, 10:56 AM
AstroApprentice (Jason)
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Retractable tripod wheels

Hi all,
I recently injured my hand and have found I need an easier way of moving my visual setup.
I've considered scoperoller http://www.scoperoller.com/index.shtml, but don't really want the tripod permanently on wheels, particularly when viewing.
I've also looked at JMI dollies http://www.jimsmobile.com/buy_wheeley_bars.htm, but they seem a bit bulky and unsightly.
Just wondering if anyone has used or is aware of retractable castors attached to a tripod? I have them on a table saw and like simply using my foot to engage/disengage the wheels e.g. https://www.carbatec.com.au/rockler-...aster-kit-pk-4. To work on a tripod the castors would have to be angled to offset the tripod leg angle, and fixed to the leg somehow.
Do you think this could be done?
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Old 01-03-2019, 11:08 AM
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doug mc
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I recently attached a length of pine framing timber to my hand truck ( trolley) with a hole in either end for the tips of my eq5 tripod. Just pull the mount back against the trolley, and you're off.
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Old 02-03-2019, 07:35 PM
Wavytone (Nick)
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Jason what surfaces do you want this to roll on ?

Many years ago I made a trolley to carry an old-school 8" f/7 newtonian by cannibalising some very wide wheels from a kids trike, they worked a treat - reasonably stable even on grass. A large contact area (ie wheels that are wide with large radius) are the key to stability and a smooth ride on rough terrain. For the same reason 4WDs have big fat tyres not skinny little wheels like a Mini, or a Daihatsu Charade.

Skinny little wheels like castors will be a total PITA.
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Old 02-03-2019, 08:05 PM
sharpiel (Les)
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What’s the EQ mount head Nick? Did you make it?

Remember the old days of ATM’ers...reading ATM Mag etc and building scopes and mounts in the shed at home..?

Old car parts and plumbing supplies were always helpful.

Nice work on your set up anyway
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Old 02-03-2019, 08:34 PM
Wavytone (Nick)
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Hi Les,

It was a frankenmount. In that pic the scope scope with a square OTA is the original 6" f/18 Loveday folded newtonian, with a 6" f/8 for comparison, as it was published in S&T. Normally though it carried 8" f/7 and one of the 6" scopes onboard.

The mount started as a AstroOptical "Goliath" with 1.5" solid shafts running in bronze bushes, but:

- the original steel central pier and legs were pretty flimsy IMHO. I made the rigid tripod using Karri floorboards glued and screwed, it was vast improvement - only thing better may have been a solid concrete block.
- the 8" diameter worm wheel and clutch was smelted, cast and machined by a friend with a machine shop. The raw material was duralumin, from several engine blocks I found on a tip, and smashed into small pieces with a 16lb sledgehammer one afternoon (I had worked as a surveyors chainman for years, and boy could I swing a sledge. A well-aimed good whack would punch a neat 3" hole in an engine block). I had a backyard BBQ made from concrete blocks which we adapted as the furnace using a vacuum cleaner in reverse to provide a forced-draft, and made a crucible made from casting clay. Loaded with coking coal the crucible was white-hot and easily hot enough to melt aluminium alloys. The alloy was cast in sand moulds as described in one of the SciAm ATM books.

Very dangerous stuff to attempt in a backyard, though we cast enough alloy blanks to keep him happy for a long time. Duralumin was apparently nice stuff to cut on a lathe, yet hard and strong - and with a significantly lower melting point than aluminium.

- parts of the mount were reinforced with welded gussets as I identified where it flexed the most.

- while living in Canberra I had the mount on the lawn trolley to move it around, as the house had an extensive garden-cum-orchard.

Always regretted swapping the 8" and mount for a C8. The 8" was far better but too heavy to manage at a time when - as a uni student - I moved to Sydney to live in shared accommodation, whereas a C8 was manageable despite comparatively poorer optics.

Last edited by Wavytone; 02-03-2019 at 08:58 PM.
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  #6  
Old 02-03-2019, 08:58 PM
rbronca
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What you seek is here.
https://blythenterprises.com.au/wp-c...spec-sheet.pdf
Easy to move, easy to adjust the level, easy to make solid. For a tripod your only decision point is how to connect the two. Maybe a trolly?
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Old 02-03-2019, 09:48 PM
sharpiel (Les)
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I have to agree with Nick here. Larger diameter wheels are better on any normal surfaces but particularly over uneven yards, lawn and pavers. I have bird cages on small castor wheels and even the tiniest of budgie seeds will cause them to stop rotating when caught under the leading edge, on even polished wooden floors.

Ease of movement comes with large wheels. Small castors seem ideal but usually disappoint.
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Old 25-04-2019, 01:18 PM
Swagman105 (Geoff)
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Homemade platform

Hi all
Like many I have the need to move my heavy rig out of the garage over some rough paving to a good viewing position on my driveway. I decided on a moveable platform on which the tripod would sit and be stabilised by raising the casters off the ground once in position.
My first attempt was a failure with too thin a ply base, too small casters and an unwieldly stabilising mechanism using inverted second hand scissor jacks on the underside of the platform to raise the wobbly casters off the ground.
I am very happy with the outcome of my Mark 2 model pictured. I used 26mm ply instead of 17mm, larger 5" casters and had some hand operated screw jacks made up out of 16mm threaded rod, with 16mm coupler nuts welded on to a solid 26mm deep u shaped bracket that fitted snugly over the ply.
An eye shackle and turnbuckle assembly attached to the underside of the mount when tightened locks the whole rig down solidly onto the platform without need of something to keep the tripod legs in position.
It works wonderfully well over some rough bits of paving and provides an almost rock solid platform as well as a place to move out associated gear like batteries and boxes of stuff.
Positioning and levelling the mount is a breeze with the casters and screw jacks. A pleasant surprise was that the screws made marks in the concrete so that the rig can be positioned precisely the same each time. I have used blocks in the picture to avoid marking our sunroom patterned concrete. My wife would kill me if I didn't.
It cost over $200 to make so was rather expensive with the most expensive part being having to pay someone to weld up the metal screw jacks as I cant weld. Nevertheless I still think it money well spent in relation to the cost of the hobby.
I am happy to supply any other details to anyone interested.
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Old 25-04-2019, 05:25 PM
Wavytone (Nick)
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Hi nicely done ! $200 well spent IMHo
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  #10  
Old 25-04-2019, 05:37 PM
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Tinderboxsky (Steve)
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Excellent result.
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