Why is the kitbot chassis bowing in horribly

Does anyone know the reasons why the top panel holding the two gearboxes together would warp horribly? Even before everything was mounted the top part was starting to buckel inwards.

Funny you mention that! Our side panel spontaneously buckled the other day. Nothing hit it, and it wasn’t hot. Very strange…

Nothing has happened to our robot yet…

large pieces of metal shouldn’t just buckle. Thats terrifying actually. Did you leave it on a heater? Did you douse in some odd chemical? Did you look at it really funny?

By side panel what do you mean, because if its one of those C sections thats really really really out of the ordinary. My only explanation for that buckling is a sledge hammer or an unlikely quantum outcome… More information would be useful is all i’m saying.

Please post some pictures and more details.

As you might imagine, I’m interested in analyzing EVERY failure.
If there is a problem, we should know about it – to effectively provide tech support to teams. Also, we’d like to try to make improvements for 2006 (assuming a similar system is provided).

Thanks,
John

I don’t know how much yours is bowing but our metal piece that fit over the transmissions is bowed down, because the transmissions are tipping in. This may not be a kit problem as we have modified the kit and will make supports so that this is not an issue.

As you might imagine, I’m interested in analyzing EVERY failure.
If there is a problem, we should know about it – to effectively provide tech support to teams. Also, we’d like to try to make improvements for 2006 (assuming a similar system is provided)…

I will try and get a picture but I do not have acess to a camera or a scanner. I have one question though. Does it matter in which one the gearboxes are orientated. Our advisor pointed out the fact that the geraboxes have a notch on one side as if they needed to be orientated in a certain direction. Fortunately we are only using this to practice with so it’s not a major disaster.

Were all the parts the same relative temperature when you tightened the hardware?

This sounds minor compared to everyone elses problems, but when bolted together in one of the suggested configurations, two rails were noticeabley not parallel (measured at ~.5" over the entire length). I did not assemble it, but I heard that the people doing it had significant trouble getting the last pieces bolted in because of the bowing.

Ya, something like that happened to ours. We built a prototype and whenever we ran it, besides it making the noise, we also found loose nuts and bolts, and so we tightened everything and then afterwards, the noise stopped. The top panel on the gearboxes might be warped because of the way you mounted it onto the two gearboxes. Probably just tightening everything might fix it.

If the transmissions are tipping in, why not add a piece of sheet metal underneath horizontally to keep them level? Just an idea.

After reading the previous posts we rechecked the bolts, and some of them were loose so that helped. Also additional pieces added to the frame under the motors and elsewhere stiffened things up.

No problems with our chassis thus far, we put it together without a problem. Just yesterday we put in the gear box cover and today got the 4WD working with the electronics.

there are no problem with our chassis too, but there are some rought sound when we run the motor (w/gearbox).

Have you greased it with lithium grease yet. If you did, was it a jelly type and not a spray out of a can. I would suggest to use a think lithium grease jelly and not just a spray. Put allot on and spread it around and then run the gearbox, this should work well and get rid of the grinding sounds from the gearboxes.

we did put grease on it, i’m not sure what type (not WD-40), is a blue jelly colored grease from motormaster

we got the can type, do you suggest we just finish off half a can in each gearbox?
:stuck_out_tongue:

how quite is your jelly-filled gearbox? how tasty?

-Leav

Problem was solved. I think they mounted the top bar to tightly and forced it on like that. It is now a nice looking chasis from which we shall practice driving with.

Did lithium grease come with the kit? If so, what does it look like ? =/

No sorry, it was not included in the kit. You should probably pick up a tube at your local hardware store