I'm looking for advice on a design for a wheel track for my 10' DIY wood dome. I'm having some issues keeping it it rotating evenly due to imperfections in not having a perfect circle. The previous attempts I've made by adding guides either on the outside of the dome or guides up against the wheels have added too much friction and uneven binding which simply have made my easy-to-rotate dome very difficult to rotate. Since I want to motorize and automate the dome soon I want something better. I think my best solution is to install a track of some design that will be very close to round, and then have a V or U wheel which will sit in that track. It should be pretty easy to locate the center of the dome, then attach a string to that point and draw a nearly perfect circle on the bottom of the dome where the track will be mounted as well as the platform that the wheels sit on. Then I can install the track and wheels on that circle, esuring that the wheels are turning on a true circle and will not bind or shift. My two design options I'm considering are with a V wheel and a T shaped track, or a U wheel and a piece of round conduit. I'm planning for 12 wheels, which should be more than enough to handle the weight, but I could do more if needed. Advantages/disadvantages I can see are:
- I'd use a 1-1/2" steel track which should be very durable and then support that with two aluminum 1/2" brackets which would be screwed into the dome (with notches cut every foot or so to allow for the bend).
- This design would allow for a perfectly smooth surface for the wheels to sit on (as opposed to screws or holes discussed below)
- It'd be super easy to bend to my perfect circle shape
- Not sure if it's a negative, but it would have only a tiny area of contact on the wheels. However that's what the V wheels are designed for.
- Something like this https://www.amazon.c...y/dp/B085C2SVNP
- I'd use a 3/4 metal conduit as my track
- I'd either attach it with screws (which would cause a tiny bump every time a screw crossed a U wheel). Or more likely drill a hole larger than the screw head, and then a smaller hole through the other side of the conduit and then the screws would go through the conduit and hold it to the dome from the inside (I would still have a tiny notch left that might cause the U wheel to slightly sit in, but this should be a lot less friction than screw heads)
- It'd be fairly easy to bend to shape, but more work to get perfect than the flat steel track mentioned above.
- It would give me more surface area for the round conduit sitting on the U wheel. Everywhere I read I hear that bigger and flat wheels that provide more surface contact is better.
- Something like this https://www.amazon.c...g/dp/B08XZBR4TK
Below I attached an image showing kind of what each track would look like, with conduit and U wheels, or the track I'd assemble for a V wheel. I'm interested in feedback on which is the better track system. OR if I should be considering something totally different. Thanks!
Edited by althor74, 24 May 2021 - 11:09 PM.