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View Full Version : pic: Swiss Cheese Weight Loss


MrBydlon
09-02-2014, 16:55
[cdm-description=photo]39517[/cdm-description]

Jon Stratis
09-02-2014, 16:59
That's a nice looking robot! I have to ask though... how far back does that hammer pull?

IKE
09-02-2014, 17:49
Some tips I have learned over the years on how to reduce weight for your robot:
http://www.chiefdelphi.com/media/papers/2220

MrBydlon
09-02-2014, 18:35
When parallel with the ground, the hammer is about 16" outside of the frame perimeter I think... It's definitely less than the 20" frame perimeter. I just can't remember the exact number.

The perspective of the camera makes the hammer look longer than it is maybe.

DonRotolo
09-02-2014, 19:12
I can imagine using something to reduce the weight of the hammer's handle. Like 1" x 1/8" square box stock.

...or just round it off and paint it silver.

Jonathan Norris
09-02-2014, 21:19
The quickest way for you guys to lose weight would be to move to smaller nuts and bolts. My eyes see a lot of 1/4" bolts, which are usually overkill for FRC. I've removed over 30 lbs of 1/4" bolts from a robot before... you can replace 1/4" bolts with #10's, #8's, and rivets in most situations.

MrBydlon
09-02-2014, 21:45
Oh for sure! We will definitely do that in the future. Thanks for the suggestions!

The power point from above was very illuminating (lots of DUHHHHHH moments that we had never really considered).

This is going to sound impossible but we had never done rivets before on a robot. I had no idea they were so simple and lightweight and just generally awesome.

We've always done 1/4-20 bolts. Like, always. The idea had never really occurred to do something different until late in the build. We will definitely be investing in more button heads and smaller bolts in the future.

Lots of learning going on this season.

Electronica1
09-02-2014, 21:46
http://m.memegen.com/qedwoo.jpg

cadandcookies
09-02-2014, 21:47
The quickest way for you guys to loose weight would be to move to smaller nuts and bolts. My eyes see a lot of 1/4" bolts, which are usually overkill for FRC. I've removed over 30 lbs of 1/4" bots from a robot before... you will find you can use #10's, #8's, and rivets in most situations.

This is so true. Unfortunately it didn't stop my team from designing around 1/4-20 because we'll have the weight for it...

kevin.li.rit
09-02-2014, 21:54
Don't forget to remove all that extra code.

Mr_D_Mentor
09-02-2014, 21:59
The quickest way for you guys to lose weight would be to move to smaller nuts and bolts. My eyes see a lot of 1/4" bolts, which are usually overkill for FRC. I've removed over 30 lbs of 1/4" bolts from a robot before... you can replace 1/4" bolts with #10's, #8's, and rivets in most situations.

For an average length of 1.5", a 1/4" bolt weighs about .022 lb, so it would take about 1350 bolts to make 30 lb.

MrBydlon
09-02-2014, 22:24
Don't forget to remove all that extra code.

I lol'd.

DELurker
10-02-2014, 07:21
This is going to sound impossible but we had never done rivets before on a robot. I had no idea they were so simple and lightweight and just generally awesome.

We have used rivets in the past. While they are easy and all that, if you do them incorrectly or overload them, they'll fail you. We might get back to rivets in the future, but it's been 5 years and the rivet aversion is still here.

Calvin Hartley
10-02-2014, 07:45
...if you do them incorrectly or overload them, they'll fail you.

I think this goes for just about any fastener.

Bill_B
10-02-2014, 07:45
For an average length of 1.5", a 1/4" bolt weighs about .022 lb, so it would take about 1350 bolts to make 30 lb.

Confirm this at this calculation site. (http://www.portlandbolt.com/tools/bolt-weight-calculator/) lots of interesting information there too. Then there are the nuts and washers . . . . ;)

Taylor
10-02-2014, 09:20
We've always been 1/4-20 folk too. This is because the IFI and AM kit chassis were all 1/4" or 3/8" holes - we just kept consistent throughout.
Now that the new AMoneforYou chassis has .190 holes, we'll be switching to 10-bolts and rivets.