pic: Cheap 6WD

[MrForbes]

We visited a friend who's into RC planes this morning, he suggested smearing some baking soda on the wood, then adding some thin CA, and beware of fumes. I guess we'll have to get some CA adhesive and make it part of our experiments.

[Ivan Helmrich]

OK, I guess I have to confess, I learned the CA trick while building RC planes. The baking soda works much like "kicker" for the CA, accelerating the cure. This may or may not be a good thing in this case. It may cause the adhesive to cure too fast, not allowing it to wick as far into the wood. I think you are right, some experimentation may be in order.

Rick, I like epoxy for this also, but the 1 to 1 mixes found at the hardware store are too thick in my opinion. A laminating epoxy like West or Pro-set are better choices. This also takes a lot longer to cure and the protective gloves warning still stands.

I like this thread, lots of good techniques for extending the utility of an inexpensive, easy to use material.

[gorrilla]

Originally Posted by Ivan Helmrich

OK, I guess I have to confess, I learned the CA trick while building RC planes. The baking soda works much like "kicker" for the CA, accelerating the cure. This may or may not be a good thing in this case. It may cause the adhesive to cure too fast, not allowing it to wick as far into the wood. I think you are right, some experimentation may be in order.

Rick, I like epoxy for this also, but the 1 to 1 mixes found at the hardware store are too thick in my opinion. A laminating epoxy like West or Pro-set are better choices. This also takes a lot longer to cure and the protective gloves warning still stands.

I like this thread, lots of good techniques for extending the utility of an inexpensive, easy to use material.

could use this perhaps http://www.3m.com/US/auto_marine_aer...ml?itemNbr=208

ive used it before on my hobie cat, its pretty tough sutff....

although ive found it does crack when there is high force dircted at it(such as if it was hit with a chisel
after it had cured)but it does work good for filling things

[Dan2081]

My team is making a similar prototype with six wheels, except we have the middle wheels powered instead of the rear. I think that this this rear drive is a better design but some people on my team don't think so. Can anyone give me any reasons why one would be better than the other (possibly someone to quote) so that I can convince my team?

thanks

[Fe_Will]

I wonder if section 4.6 of the manual also applies just to the crate or everything being shipped?

http://www.usfirst.org/community/frc...nt.aspx?id=452

[s_forbes]

Originally Posted by Fe_Will

I wonder if section 4.6 of the manual also applies just to the crate or everything being shipped?

http://www.usfirst.org/community/frc...nt.aspx?id=452

To save others the trouble of looking it up:

Originally Posted by 4.6.1

The following regulation applies to any team planning to ship its robot into the U.S. from another country. Teams that do not comply risk having their robots detained at the U.S. border by U.S. Customs and not arriving at the event on time.
The U.S. Dept. of Agriculture has adopted international guidelines to decrease the potential for the introduction of certain plant pests that may accompany wood materials arriving from other countries. The crate construction and pallet guidelines stipulate that wood packing materials be either heat treated or fumigated with methyl bromide in accordance with applicable rules. These wood materials must have the approved international mark certifying treatment.

Interesting catch if it applies, but if this rule only applies to "wood packing materials" then I don't think it would be a problem. (Our robot was denied shipment because it's full of bugs!)

Originally Posted by Dan2081

My team is making a similar prototype with six wheels, except we have the middle wheels powered instead of the rear. I think that this this rear drive is a better design but some people on my team don't think so. Can anyone give me any reasons why one would be better than the other (possibly someone to quote) so that I can convince my team?

thanks

I don't think either arrangement offers much over the other; they're very similar. I arrived at the configuration pictured because of some decisions I made about the way I wanted to build it:
-To make mounting the transmission easy, it would be face mounted to the wood (so no chain can run from the transmission on the inside of the frame)
-To minimize bending load on the transmission shaft, the directly-driven wheel needs to be as close in to the frame as possible. This means only one chain can be connected to the driven wheel, which means the transmission needs to be on an end.
This obviously doesn't apply to all designs, it's just the path I took for this particular one.