pic: New Chassis Concept

[R.C.]

Originally Posted by chris31

Yeah. I have a few ideas starting to be drawn. Just nothing is final in CAD yet.

Its McMaster 1630T14. So you recommending something thinner with less pocketing. Thats doable. Im still playing around with best ideas for removing weight and keeping strength.

Chris I like your stuff and if you need any help with CAD, please email me. Try using 1x2 aluminum. We have using a 1/16 wall and it is fairly light. You can even pocket some out on the sides but none on the top. We created a frame that had a ton of cnc work and played battle bots with it to see if it would crumble. Plus stress testing told us it would be fine. Make sure you have a safety factor of 10 ((Just to be extremely Safe))

[chris31]

Just the 6 pieces of C channel totally 14.13 pounds whereas the same length of 1x2 with 1/6in walls is about 7.7 so I see what you are saying about weight.

Cory, whats so hard about machining C channel? Im not a machinist but the machinist didnt say anything when I drew a quick concept for him.

[AdamHeard]

Originally Posted by chris31

Just the 6 pieces of C channel totally 14.13 pounds whereas the same length of 1x2 with 1/6in walls is about 7.7 so I see what you are saying about weight.

Cory, whats so hard about machining C channel? Im not a machinist but the machinist didnt say anything when I drew a quick concept for him.

Both the cutter and the vice exert lots of force on the part. Square/rectangular tubing has walls that resist forces rather well in all directions square to a face. C channell is "missing" a side which often can make it hard to clamp in certain orientations (for example, vertically you'd only be holding the ends of the bottom leg), and hard to actually cut in certain orientations (the legs will deflect from the cutter probably, leaving poor finishes). There are ways to get around that of course, but ideally you'd make machining as easy as possible.

The 2x1 will also result in a much more rigid frame, it doesn't twist along it's own long axis as easily as the C channel will.

[meastman]

Our team's robot for the last few years has had the motors directly drive the middle wheel. This could make turning easier if you drove those wheels instead

[gorrilla]

not to be negative but,

could just save yourself the trouble and use the kitbot chasssis....................

would loose the cool factor though.........

[chris31]

Adam, that makes sense. Thanks for the input.

Originally Posted by meastman

Our team's robot for the last few years has had the motors directly drive the middle wheel. This could make turning easier if you drove those wheels instead

All six wheels are powered in this design.

Originally Posted by gorrilla

not to be negative but,

could just save yourself the trouble and use the kitbot chasssis....................

would loose the cool factor though.........

Well, that kind of defeats the purpose of having the chassis design the way you want it and work to your needs. It also wouldnt be much of a learning experience to just bolt some frame material together.

[gorrilla]

Originally Posted by chris31

Adam, that makes sense. Thanks for the input.



All six wheels are powered in this design.



Well, that kind of defeats the purpose of having the chassis design the way you want it and work to your needs. It also wouldnt be much of a learning experience to just bolt some frame material together.

yeah but it saves money and valuable time.

any other teams weld theirs?

[chris31]

Originally Posted by gorrilla

yeah but it saves money and valuable time.

any other teams weld theirs?

Sorry, Im not really looking for recommendations on why I should use the kitbot chassis.

[gorrilla]

Originally Posted by chris31

Sorry, Im not really looking for recommendations on why I should use the kitbot chassis.

well i was just putting it out there...............

[sdcantrell56]

Now is the time to be designing new drivetrains, and telling a team to just use the kit frame right now is not really a good way to encourage new development and growth. Yes in some instances and for some teams it would be better to just use the kit frame; however, a lot of teams can pull off a better custom chassis that fits there needs perfectly. Also we don't even know if we will be given the same kit frame this season.

[gorrilla]

Originally Posted by sdcantrell56

Now is the time to be designing new drivetrains, and telling a team to just use the kit frame right now is not really a good way to encourage new development and growth. Yes in some instances and for some teams it would be better to just use the kit frame; however, a lot of teams can pull off a better custom chassis that fits there needs perfectly. Also we don't even know if we will be given the same kit frame this season.

i know this, and it was just a suggestion...

i also know that if my team had access to all the tools and materials needed, we probobly would...

i am all for encouragement and new growth, just commenting.......

[sdcantrell56]

You should look into having standoffs between the plates. That would add a ton of strength.

[chris31]

Originally Posted by sdcantrell56

You should look into having standoffs between the plates. That would add a ton of strength.

Thanks for the recommendation. Ill be working them into the design after I finish finals (tomorrow).

[sdcantrell56]

If you have the resources, I would recomend making your own standoffs out of delrin. This way they could be a larger diameter and distribute the load better and still be lighter than aluminum standoffs.

[AdamHeard]

Originally Posted by sdcantrell56

If you have the resources, I would recomend making your own standoffs out of delrin. This way they could be a larger diameter and distribute the load better and still be lighter than aluminum standoffs.

If the delrin standoffs are threaded, they will be much lighter than aluminum overall, but the threads won't hold up real well.

If the they are thru holes, they bolt increases the weight a lot as it is rather long. I'd Imagine an aluminum standoff with tapped ends is lighter than a delrin standoff with a thru bolt of comparable strength,