Boomilever B/C

[Jim_R]

Boomilever Wiki
2013 Thread
Boomilever Image Gallery

[johnguackmbl]

Some of the new 2014 resources on the soinc.org website. Can anyone tell me / diagram for me how a boomilever would attach to the wall with a J-bolt?

http://www.soinc.org/sites/default/file ... ns2014.pdf
http://www.soinc.org/sites/default/file ... lation.pdf
http://www.soinc.org/sites/default/file ... nStick.pdf

[iwonder]

That's really interesting... I would think initially the base from last year could be replaced with a dowel or rounded out piece of balsa that could slip into the j-hook and rest against it. It definitely gets rid of the issues of washers from last year

[balsa]

So excited for this upcoming season, the new J-bolt solves alot of limiting factors that were preventing booms from scoring higher with the past bolting system (easier mounting, so theres almost no way to incorrectly mount; booms won't slip off of the mounting wall, etc.)

[fanjiatian]

Thank you for posting the testing apparatus set up!
I'm also confused about how to attach the base to the J-hook: would you need two holes? or a different shape?
Could someone explain this?

Also, what's the point of having a spring on the stabilization handle? I understand that the new rule prevents team members from touching buckets with their hands, but a stick with a spring?
Why not just a stick?

[iwonder]

I think the base from last year would be gone completely, you could just put a piece of wood between the tension members to hook onto the j-hook.

And the springs have been used at nats for a while, it makes it so you can't lift/support the bucket with a wooden stick. If you tried the spring would bend.

[jander14indoor]

The J hooks will absolutely require you to change the base, you have to slide your base over the hook, not remove and replace the hook through your base.

And DON'T underestimate how much thought, design work and testing will have to go into your new bases. It will still be the highest stressed part of your design, and if you aren't careful, the heaviest.

At first blush, the base would be a moderately hard piece of wood fitted closely to the inside of the J-hook and just over the thickness of the hook. Your tension pieces would then be attached to the sides of that piece (similar issues of high stress as the previous bases). Trick will be how 'moderately hard' is hard enough to not crush under the load and to provide a secure base large enough to attach the tension pieces too. Also how small you can get away with for this inner piece.

I'm also wondering about stability. Not much to prevent swaying side to side which will get you in trouble in a HURRY.

Hmm, thoughts on the grain for that centerpiece. I think you will want the grain pointing along the tension member as that's the most efficient direction to resist crush and allow the members to be attached long grain to long grain. Might bring up an issue of splitting.

I suspect once you get out very far (a few inches at most) from the attachment point, all the things/approaches used in prior years should still work.

Just some things to think about, have fun!

Jeff Anderson
Livonia, MI

[UQOnyx]

I am very very confused. Is the base supposed to 'hook' on to the J-bolt? Does that mean that the base will not rest on the testing wall? Can someone please post a diagram or a picture of how the boomilever will be mounted?

[jander14indoor]

I don't have the rules on hand, so this is from memory, check rules for yourself.

The hooks are FIXED this year. You will have to slide the base over the gap and into the hook. I don't think the rules require the base to touch the wall, equally importantly, I don't see how you can slide them over the opening and into the hook and still touch the wall.

UNLESS it is required and you have to slide the base over the hook and slide a pin of some sort through the base on into the hook.

Pictures, sorry not my forte.
First case, think of the base as a loop of wood on the end of your tension members that slips over the hook.
Second case, think of the end of the tension member as a fork that slips around the hook sides and you have a pin of some sort between the fork tines that keeps it from slipping back.

Either way, VERY different base from prior years.

Jeff Anderson
Livonia, MI

[UQOnyx]

So does that mean that you are literally hooking on the boom to the testing wall? If it is being hooked on, though I'm not sure it may be a good idea, can't you get rid of a base altogether? Instead can't you bend the tension members in U-Shape in a jig, with the bend of the U being where the base is, and the forks of the U being the far end of the boom, and then just hook the U on the J-Hook?

Also, the wiki needs to be updated to reflect rule changes and to guide people like me .