I’m teaching 5th grade Project Lead the Way and I’m having some trouble with the tank treads breaking whenever I try to shorten or lengthen them. Is there a trick to making these connections or are they just poorly designed?
They want to run in a straight line, so any misalignment of the axles is an issue.
They are not designed to lift large loads, that may cause them to separate.
Finally they don’t deal with a lot of tension. I’ve found that it’s important to support both sides of the sprocket (so they are not cantilevered) so that a lot of tension is not needed.
Can you post a picture of what you are trying to do?
Thanks!
Foster
Is this when you try to separate two treads? Or when you attach them? If so, there are ways to twist a little (hold each tread firmly, pull one a little sideways to the other to create slack on one side) and pry a little and pop one lug off or on. Small screwdriver or thick fingernail… No pliers, for sure.
Let us know how it goes… pic or vid helps.
Guessing you mean the little tabs with the holes in that snap onto the studs of the next link are breaking off? I can’t say I have ever broken one to be honest.
You need to pry one side up real gently when taking them apart… if you just twist them they will break one side off. We have gone through a lot of tread teaching the kids how to separate them.
It’s been the little tabs that fit over the holes that are breaking off. I’ve had better luck using a flat staple remover to pry them up but they’re still breaking on occasion.
Ime just twisting breaks them often.
Just prying breaks them too.
A combination of stressing one a little “sideways” to the other - and a little twist - and a little pry does not break them.
Separating is harder than connecting.
Look closely, you want to spread the stress to both tabs, not concentrate it on one. Seems to take three hands at first, but there are ways… I hold one tread (and treads next to it) with outside three fingers so thumb and forefinger can pry. Holding one tread (and any attached) down onto the table can help.
I’ve gotten 3rd graders to learn how by watching what they are doing, though had one 5th grader who liked to break them.
one problem with small parts made of ABS(Acrylonitrile butadiene styrene - Wikipedia) is that they weaken in the Sun or Heat. have any of your tank tread links been left in heat or the sun? we have had 3d printed parts fall of if given a little bit of force, be sure to check out the link below on that. because i don’t think there is any other reason other than improperly separating them or using #BRUTEFORCE
ABS weathering - Filament - LulzBot
FYI: while the VEX IQ beams and plates are made from ABS, the chain and tank tread links are made from Nylon.
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Sorry About that, even though it is a different material Nylon is still like ABS when it is hit with sunlight or UV.
“Nylon can also be negatively impacted from UV exposure, primarily from direct sunlight”
https://www.creativemechanisms.com/blog/3d-printing-injection-molding-cnc-nylon-plastic-pa