tabletop dolly
 

I'm going to build a trackless tabletop dolly with skate wheels. Trying to decide - 3 wheels or 4? 4 wheels would have a bit more stability, but on a tight circle 3 wheels seem like they might pivot better? any feedback?

(edit)

The more I'm thinking about it, seems that with 4 wheels, uneven surface could cause one wheel to not be in contact, resulting in rocking motion. 3 wheels will always be in contact with surface.

So I'm leaning toward 3 wheels, with one wheel "fixed" and 2 wheels "steerable"

Re: tabletop dolly
 

I've just built a tracking dolly using skate wheels. This was the second attempt after using plastic wheels with plain bearings which was hopeless. My second attempt used all eight wheels from some used skates that I paid NZ$15 for from TradeMe (our version of eBay) and used the wheels two each side of each axil to ride on a tubed track. I have just tried the dolly on a flat surface, and it really doesn't want to move in an arc - even a very shallow one - so I think you'd need to swivel the axils for a tight curve.

I am keeping the first dolly with the plain bearings for curved tracking shots.

BTW I was having alignment strange problems with my skate wheel build, until I realised that the two center wheels are slightly larger diameter than the outside wheels. (80mm vs 84mm)

Re: tabletop dolly
 

I went with a 3 wheel design - with a triangular hardwood base - two of the wheels are adjustable to allow it to curve - very stable. I'm painting it black today.

Re: tabletop dolly
 

I painted it black but the paint is very soft, so i need to coat with polyurethane. it's tough to spray paint outside in frozen Michigan in winter!

I made two interchangeable camera mounts for it: a fixed quick-release that will spin horizontally 360 degrees...and a modified still camera tripod head that will allow a tilted angle.

Re: tabletop dolly
 

The finished dolly - with the head of a garage sale tripod w/ quick release base attached. it's about 12" per side.