Riveting the KOP Frame

[BrendanB]

Our team is currently working on cutting back on our weight. The andymark KOP frame has 32 nuts and 32 bolts holding it together and I am considering replacing them with bolts. We have we have 3/4inch long rivets so they do not go through the frame so I was considering using one on the top and bottom. How much of a problem would it be to rivet the frame together? Should we rivet them all, rivet half, or don't do it at all?

Any thoughts would be very welcome!

[WileyB-J]

think about emergency disassembly before you do anything, what would you need taken apart to service your robot?

[BrendanB]

Originally Posted by WileyB-J

think about emergency disassembly before you do anything, what would you need taken apart to service your robot?

In 3 years of FRC, the only time I have had to take apart a frame was last year and it was 80-20 and it was a very rare instance. We have nothing this year that would require it

Attached is a photo of the corners I am considering riveting:

[wilsonmw04]

we have riveted our entire frame before. It is a great option. You get a nice tight fit and you don't have to worry about nuts coming loose. Some folks on this board have bet they can drill out a rivet faster than you can remove a nut and bolt...

[WileyB-J]

then its your judgement on that, rivets have been used on various robots ive seen and hold up. remember to bring a rivet gun + extra rivets just in case!

[zbanks]

You say you're doing this to cut back on weight.

I'd first make check to see how much weight you'll actually save. You don't want to do all of that to save 0.1lbs.

[BrendanB]

Originally Posted by zbanks

You say you're doing this to cut back on weight.

I'd first make check to see how much weight you'll actually save. You don't want to do all of that to save 0.1lbs.

The weight difference between two rivets and one bolt and a nut is noticeable and multiply that times 32 equals is significant. It is just the structural integrity that is my concern.

[Vikesrock]

Originally Posted by BrendanB

The weight difference between two rivets and one bolt and a nut is noticeable and multiply that times 32 equals is significant. It is just the structural integrity that is my concern.

You will also have to add in the weight of gusset plates for each corner, and subtract the weight of those solid corner connectors. If your rivets don't go all the way through, they won't work with the corner connectors.

[wilsonmw04]

Originally Posted by BrendanB

The weight difference between two rivets and one bolt and a nut is noticeable and multiply that times 32 equals is significant. It is just the structural integrity that is my concern.

We saved close to two pounds moving over to rivets one year. Again, the forces that these rivets will be under should not be an issue for your standard aluminum 1/4" rivet. We didn't have a failure because of wear, only improper installation.

[Dad1279]

We have been riveting for a few years now. No problems. And replacing the corner connectors with 1/8" plates will save alot of weight also.

[Nathan Streeter]

Brendan, I'd suggest making the switch to rivets if you can manufacture the 16+ L-shaped plates for each robot. I'm pretty sure you could expect to save ~2 pounds by swapping out all the bolts and funny connectors for little corner plates and rivets.

You know we've used rivets plenty of time with success on the IFI old KOP frame... I'm sure they'd work comparably well with gusset plates.

[BrendanB]

Originally Posted by Nathan Streeter

Brendan, I'd suggest making the switch to rivets if you can manufacture the 16+ L-shaped plates for each robot. I'm pretty sure you could expect to save ~2 pounds by swapping out all the bolts and funny connectors for little corner plates and rivets.

You know we've used rivets plenty of time with success on the IFI old KOP frame... I'm sure they'd work comparably well with gusset plates.

I know we have done it in the past with the IFI frame the Andymark frame is different which makes the riveting interesting/sketchy since the rivet cannot expand as much.

Thanks for all the suggestions!

[Vikesrock]

Originally Posted by BrendanB

I know we have done it in the past with the IFI frame the Andymark frame is different which makes the riveting interesting/sketchy since the rivet cannot expand as much.

Thanks for all the suggestions!

I would not try and rivet the KOP corner connectors, there is nothing there for the rivet to grab. If you want to go with rivets you'll want to make L or triangular plates to secure the corners and ditch the KOP connectors.

[MrForbes]

As many tall robots as there are this year, I expect we'll see lots of falling over...and if you are using the kit chassis and you have to lose 2 pounds, you might be better off trying to find two pounds that sits a lot higher off the ground, to go chasing after. That would let you lose the weight and keep the robot upright more often.

I love rivets, but the kit chassis is not really designed to be riveted together. As mentioned, if you make your own end brackets from flat aluminum and rivet them on you could achieve what you want. You can use the chassis as a drilling guide, too.

Good luck! sounds like you will have a busy next few days

[Chris is me]

You can take two pounds out of those transmissions instead of riveting the chassis. I love rivets but you can't rivet those corner brackets.