Easy Bumper Switching?

[Oblarg]

Clevis/cotter pins work really well.

[bobbysq]

We use clip-on nuts on the frame of our robot (affectionately called "super-nuts") and then use a drill to bolt on our bumpers.

[snoman]

We made our own kinda like this.
https://youtu.be/DlyujQaTLlA
And they were fantastic.

[Type]

In the past my team has used C channel with pins, as it sounds like most people have done. This year we tried to do the same thing but we didn't make our robot out of C channel (first in team history I believe), and we realized the way we wanted to mount it did not meet the rules. Our solution was angle iron on the bumper, and a flange on the frame perimeter. We drill and taped holes into the frame perimeter bumper mounts and drill matching holes on the bumper- bumper mounts. In the end, we had I believe 3/8" bolts6 10-32 (or 10-24, too long ago ) holding our bumpers in. There were 2 on the left and right sides of the robot, and 2 on the front (one on each side of the opening). These were one piece bumpers we used. Throughout the season the holes started stripping out so we used flanged nuts on the end of our bumper bolts. Just turn them finger tight and we never had an issue, easy to get off too. With 2 guys, we could get the bumpers are within about 30 seconds. These mounts were strong enough where we could carry the robot by the bumpers, and not cause any harm to the robot.

[cad321]

Originally Posted by snoman

We made our own kinda like this.
https://youtu.be/DlyujQaTLlA
And they were fantastic.

I really like the design of these bumpers. I don't suppose you have any resources on how you went about making these? Templates, photos of construction, general tips etc.

[Brandon_L]

I've found reversable bumpers to be really easy to use. Look up on CD media, there's patterns floating around. If you don't want to get that fancy, you can make your bumper a single color and have a cover of the opposite color Velcro over it. Industrial Velcro is magical, I've used it in the past to hold our electronics and it held perfectly fine through heavy impacts.

[Chief Hedgehog]

Originally Posted by BigBen

We have a mentor that does a decent amount of sewing and have had the students do reversible bumpers in house the last few years, similar to the RoboPromo kit:

http://www.robopromo.com/product_p/rp-2004.htm

The video at the bottom of the page does a decent job of walking through the process. Words of caution, make sure they are centered vertically on the board, as tight on the board as possible and that the Velcro on top and bottom has several staples through it. That keeps the Velcro from loosening due to movement of the cloth on the wood backing. Also we use full strips of Velcro at on the top and bottom.

This allows us to permanently mount the bumpers.

This. Make the leap to reversible bumpers as soon as you can. The amount of time that reversible bumpers save is priceless.

[FrankJ]

For those making convertible bumpers, Keep in mind the bumpers still have to be easily removable (quick and easy per the 2016 rules) for inspection.

[snoman]

Originally Posted by cad321

I really like the design of these bumpers. I don't suppose you have any resources on how you went about making these? Templates, photos of construction, general tips etc.

i can make a video taking one apart. One of our other mentors did the sewing on them and she is not with us anymore. I will put it on the To Do list.

[nickmcski]

I loved using Pip Pins for our bumpers! Very similar to the grenade pins mentioned about but you have to press the button on the top before removing the pin. The pins are VERY secure, it's almost impossible to accidentally push down that button and simultaneously pull up the pin.

[arc25565]

Those Pip Pins are the best, we have never had one fall out in competition and they are easy to change.

[Bob Steele]

Originally Posted by EricH

This last season, we built 1-piece bumpers, then put an L-angle along the sides. On the robot, we welded some toggle clamps. Pop the clamps, pull the bumper off, put the other one on, lock the clamps down. Didn't lose a bumper all season (though we did do a rebuild for Champs). I want to say we "borrowed" the idea from Citrus or Poofs or someone up that way.

After years of doing convertible bumpers...we switched last year to a similar method as described above. We actually design the bumpers to provide part of the structure of the sides of the robot (within the rules of course) We use an L bracket and the toggles on top. The frame is sized so that the bumper just slips right on. Last year, because we had an opening in the bumper, we put in two simple pins into the frame on either side of the opening that would not allow the bumper to spread apart considering that the toggles only utilize compression and have little shear support.

One piece bumpers.... the way to go if you can do it. Bumper change in about 15 seconds.... removal even quicker.... great for inspection and in the pits to access everything easily. Also easier to transport by removing the bumpers.... They are also much easier to make look really nice and tight.

[Travis Schuh]

Originally Posted by bstew

It looks like we played around half as many matches overall (season and offseason) in 2016, so we probably don't see as much wear as you do. That being said, we build pretty rigid (one piece) bumpers out of bent 1/8 6061 T6 aluminum sheetmetal. They really don't change shape at all during the season. This probably helps the latches avoid some problems.

Could you provide more information on your mounting setup? We mount our latches so that the 1/8 L brackets supports them and should take all horizontal forces. All the latch should be doing is holding the bumper down.

I like your internal sheet frame structure, that could help with a lot of the bumper fit problems we have. We had similar L brackets (probably custom 090 sheet). I also don't think we were as careful with installation.

[marshmello]

Our team uses reversible bumper covers: essentially, we attach one color bumper cloth to the bottom of the bumper and the other to the top, sew the cloths together where they meet in the center of the bumper, and add velcro all around the edges, so you end up with a flap that "hinges" in the middle of the bumper. It switches colors in less than 10 seconds and saves bumper material. If you can find someone capable of sewing reversible covers, I very highly recommend it.

[livia.13]

Okay-so we glued/sewed (I don't know which, I wasn't on the team when they made them) a piece of thick red fabric on a piece of blue fabric, both the same size. We attached velcro to the fabric for the bumpers and the bumpers themselves, and could easily switch them. We also added our team number on both sides with tape! Good luck!