Re: How are bellypans made?
 

FRC2168 has been using this stuff the last few years: McMaster 84825K89

I learned about it while at college with FRC229, they used it for their ramps back in 2007. It's listed as Noncorrugated Panels, is about 1/4" but the stuff is super light weight and can handle a good amount of weight.

Note: I've heard it called Polygal, but I believe that is the whole Kleenex vs tissue paper argument.

Re: How are bellypans made?
 

To give the students some exposure to composites, we use a piece of 1/4" plywood laminated with 6 oz. carbon on both sides.

Re: How are bellypans made?
 

Where to do you get yours? Can the 6061 be waterjetted instead?

Re: How are bellypans made?
 

Any metal supplier will have 6061 sheet. Yes a waterjet works the same.

Re: How are bellypans made?
 

Thanks!

Re: How are bellypans made?
 

Last year we used a honeycomb fiberglass, the only problem was that some adhesives, such as Velcro tape, did not stick well. You can drill holes for support but you must have washers along with the nuts for the bolts.

Re: How are bellypans made?
 

We use this for mounting electronics and other materials. Lightweight, easy to mount to, easy to work with -

http://www.andymark.com/product-p/am-0836.htm

Re: How are bellypans made?
 

Use fiberglass instead carbon if mounting electronics, or coated it with some clear coats. Same with using aluminum sheet, paint it so it's not conductive. I've seen too many times a live wire come loose and touch the mounting board. Also instead of plywood, use a foam core and save yourself a ton weight!

Re: How are bellypans made?
 

We CAD ours and a sponsor water-jets it from 1/4 inch aluminum. We then tap directly into it and attach our electronics that way.

Previous to this we used ABS and nuts and bolts. However, in 2010 and 2011 we had so little clearance under the robot that we had to tap the baseplate or countersink flat-head bolts from the bottom up.

Re: How are bellypans made?
 

Last year, 1370 used 3/4" plywood (Lowes) to mount all of the electronics on. This year, because we were afraid of the weight limit (rightly so, it turns out), we used 1/8" Lexan. Band saws, vertical mills, and circular saws with either forward or reversed blades works just fine. Unfortunately, our Lexan was a little too gummy to use the tried-and-true method of score it and snap it at the line.

Re: How are bellypans made?
 

2079 laser cuts 1/16 5052 aluminum sheets. The only reason we use 5052 is because we put flanges on the edges, but 6061 is stiffer (or at least a standard T6 temper is). Our shop doesn't like to laser thick aluminum because of its reflective properties that damage the laser, but if you want to do thick stuff you can use a waterjet. I don't see a need to use anything thicker than 1/8 for a belly pan anyway, but I guess there could be a reason sometime.

Re: How are bellypans made?
 

6061 T6 is not stiffer, but it is stronger. Nearly all aluminum alloys have essentially the same stiffness (elastic modulus).

Re: How are bellypans made?
 

We used .09 laser cut 5052-H32 sheet. It was bent with the back piece of the chassis as the flange (suggested to us by Sean from 2415). We did not add much lightening this year, but for next year we will definitely be using the diamond pattern commonly used by 254 etc.. Here's a picture

Re: How are bellypans made?
 

If you can score and snap it, it's not polycarbonate! It's most likely acrylic (Plexiglass).

I'm not too keen on starting with a material that needs a lot of cutting to make it do the job, for any part of the robot. But I guess if you have access to machinery that can do this, and you like drawing neat designs in CAD, then it kind of makes sense. We usually do fine with a sheet of plywood, of a suitable thickness for what's attaching to it and how big of an area it spans.

Re: How are bellypans made?
 

I have used 5052 and 6061 on belly pans with great success in each. The 5052 does flex a smidge more I found, but overall does what it needs to. Its what the sponsor had on hand at quick supply so we dealt with it. Even had to cut one of the belly pans in half since we had parts that didn't hit the tolerance we needed by some random chance. I'm not sure what happened but the bending was free so I'm not complaining.

- Andrew