I heard many mention trying to acheive a slow crawl with a dolly, and some people talked about hooking up some sort of slow turing motor to do this smoothly. Well, I have an idea and want to hear what you all think. What if you mounted a fishing reel (just the reel) to a 2 foot long 1"X6" board, stood on each end of it with the reel between your feet, and literally reeled the dolly towards you. With some heavy fishing line and a low gear ratio reel, you could keep the speed consistant. What do you all think?

That sounds like a reel great idea!

Fishing reels usually have a rather fast retrieve: They're geared that way to get the line in quickly. Some have two speed settings to deal with heavy loads (something we all wish for) or for a fast retrieve in case the fish makes a run toward the boat.

If you want to use a motor, there are geared low-speed motors that run film processors, etc, which might be available at surplus outlets. There was a place here in Honolulu that sold stuff like that but they went out of business.

Or you might want to create a simple hand-cranked, spool-type device. Use a long handle with a small spool and you'll get a slow retrieve.

Yeah after I posted this, I played with some of my fishing reels, and they are kind of fast at the retrieve. That's when, like you said, I realized some type of big handle/little spool type device would work best. I just figured it would be a lot cheaper than a motor, and its speed could be variable as well.

How about a boat trailer winch. They have a nice thick strap, and a low gear ratio. Just need to hold or remove the ratchet mechanism.

Just something to think about.

-gb-

Or a garage door opener. You can even operate it with a remote control. :)

reviving this as I want to do this so i can do timelapse dolly shots...

something like this ?

http://www.trevswork.com/mo/

You can use a motor from a rotating disco ball. You can find them here: http://www.sciplus.com/singleItem.cfm/terms/12254

5 rpm and runs between 6-12 V DC, (very easy to keep it portable). You can attach a larger pulley wheel to the motor to collect the string attached to your dolly.

And with a bit of luck, even free!

A surplus/ trashed battery powered drill. See 'em turfed out every day (usually 'cos the NiCad's have died).

The motors/ gearboxes have more grunt than you'd give them credit for and have speed control built in, the chuck allows you to afix just about any type of spindle/ reel system you can devise and most will work off a 12 volt lead acid battery no matter what their stated voltages are.

Worth a try.


CS

it needs to be REALLY slow though

it needs to be REALLY slow though

Make it a union job? ;)

Hello Philip,

How slow is slow?

1 meter/second? 10 cm/second? 1cm/second?

Slow speeds does not necessarily mean small motor... For a decent move with no vibrations you will need a strong motor with a big rotation-reducer. In combination with a small pulley you have the power and reduce the speed.
A slow rotating motor will always have its vibrations: So you will need to let your motor run at max speed and reduce speed with gearboxes and pulleys..

A source could be an electrical step?

Onno Perdijk
Key Grip / Manufacturer
Netherlands
www.solidgripsystems.eu

btw:

a 2000 rpm motor with a 1/30 reductor and a pulley of 6cm will give you a max speed of 21 cm/second....

This combi can pull a 50kg straight-line. So the dolly-weight on smooth running track can be over 200kg... (just finished math-school, :-) )

Onno

can you make me one?

Hello Philip,

No problem, I can make you one. Does 21cm/second sounds good to you? Or do you want to go less speed?

What others specs do you have? Track gauge, Height of the pulley?

pricing is 900 till 1500 depending your demands and how much DIY you want to do.

Please call me: +31653201455

Best regards,

Onno


Onno Perdijk
Key Grip / Manufacturer
Netherlands
www.solidgripsystems.eu

Chris Li..... that was way cool..... thanks for posting that.

Test number 1
YouTube - First test with DIY dolly and slow motor (http://www.youtube.com/watch?v=5_NzTRPLKDA)

test number 2
YouTube - Sunset timelapse test - with moving diy dolly (http://www.youtube.com/watch?v=3uxQTLxhv3E)

Here is a DIY slow torque motor dolly i did..
At the end of the first video you can se some stills of the motor i used.
Its a regular 230v mirrorball motor. it moves at about 12cm pr min.
to slow it down to 6cm pr minute i did a pulley system with two strings.

You might try here for motor ideas.

https://bmumford.securewebsites.com/photo/rotary/index.html


Rotary Table Controller (http://www.bmumford.com/rotary/index.html)


Good Luck with your project!