# Weights of Hardware

Does anyone have the weights or have the ability to precisely weigh all the sizes of Vex screws, keps nuts, lock nuts, 12" of axle, and other pieces of Vex hardware?

I am trying to get an idea of just how significant a few screws here and there are toward the weight of the robot.

Thanks in advance for any help.

It might help if you measure, say, 10 of a length of a screw so you get an average, and circumvent measurement errors.

The weight of hardware is HUGE. I tried to collect up all of the hardware I used on my 2010 robot when I took it apart and it was ridiculously heavy, I remember it all adding up to a little over 4 pounds. I used a ton of hardware on that robot, way too much to be honest.

As far as measuring the weights of all the hardware I would suggest measuring 100 pieces and divide out if you wish but you are likely going to end up using keps nuts by the hundred…

~DK

Wow. I thought it might be such a significant number. I’m definitely going to have to limit my use of hardware.

The problem I have is that I don’t have a scale with which to measure any of the hardware I have. Also, because we have a robot already built, I don’t have one hundred of any one piece of hardware. I’ll probably end up having to buy a scale and measure the average of ten of each type.

Does anyone know a store where I could buy a scale that could measure very small weights? I’d prefer it not to be online so that way I can just go get one.

I suggest looking into scales designed to determine postage weight. I got mine online, but I’ve seen them at Staples and similar stores.

The biggest problem that I found with vex hardware is that although you may only need the strength of one piece of hardware (if that) you sometimes end up needing to use two the really hold everything together, because one piece is just a pin joint. You have to just limit yourself early, I find myself saying “oh, one extra bolt won’t hurt anything” the problem is I say this A LOT.

As for the scale, do you have access to your school at all? I figure you could try to use one of theirs because a good scale is not going to be cheap (some of the scales we used in chemistry last year cost \$6K).

~DK

I find myself saying that about hardware as well haha. I guess I’ll just go through my entire robot and strip off any un-needed hardware.

I don’t have access to my school right now, but I may be able to ask one of my teachers about it. I guess it’s not too urgent. I can figure that out later.

Also, what would you say is greater: Double the needed hardware on a particular robot versus the minimum amount or the difference between 5 hole channel and 2 hole c channel.

Let’s say that there are six pieces of aluminum 35 long 5 hole c channel that could potentially be swapped out for 2 hole aluminum c channel. Would this be worth a significant amount of modifications? Could I save the same weight by stripping down hardware?

I’d really like to do calculations on these questions, but for now I’ll just estimate stuff.

There is a lot of information that I just don’t have to make that call. Mainly, how much is the “needed hardware” amount and how long is the hardware you are using? Also don’t forget that all c channel is not created equal, if you need the strength or size of the 5 hole c channel you obviously can’t swap it out. I know in Vex a lot of times even aluminum 2 hole c channel is way over built for its applications but definitely think about the swap between 5 and 2 hole aluminum before you make it.

~DK

This question was also asked a couple of months ago and JVN was going to put one of his interns on the task.

There is also some info available on the internet such as this site.

http://www.engineeredpartsinc.com/weights.htm

Right. I understand. The main swap I am considering is in my drive train. We are currently using 5 hole c channel and were considering using 2 hole. Structurally it would serve the same purpose, however it is more difficult to incorporate with our design so I was trying to weigh the advantages with the disadvantages. I’ll keep figuring that out using estimation though.

There is also some info available on the internet such as this site.

http://www.engineeredpartsinc.com/weights.htm

I saw that thread, but I was wondering if anyone had since weighed the parts. Thanks for the link to the other site. That should be useful.

Inventor also gives reasonable estimates.

From the above site, 1000 x 1/2 inch 8-32 screws weigh 4lb. So 100 should weigh 0.4 lb. I dropped 100 8-32 screws into inventor which had their material set as stainless steel, mass of the assembly was shown as 0.432 lb, about 10% more. Close enough for our needs.

Something else you might want to think about is were the weight is. This year since I don’t have to worry about hanging on the ladder I think my team might go for steal instead of aluminum for the drive train to lower our center of gravity. On the other hand the hardware will be more spread out not only on the drive. Of course if the drive is stuggling to move the robot or you want it to have more power and you have no problem with tipping, then you might want to consider the 2 hole for the weight. I’m not trying to tell you not to use 2 hole c-channel, but the weight of the c-channel is not something to normally worry about for the drive unless you have the same conditions as stated above or it is being used higher up the robot like an arm.

I understand your concern. I agree that making the drive train lighter is a potential problem due to tipping. I cannot guarantee that our robot will not tip if I swap out those pieces, so I may not try it. In the current configuration, the drive train has plenty of torque to move the robot and the robot is virtually unable to be tipped even when extended to be able to score at 30 inches. If it ain’t broke, don’t fix it, huh? Haha.

Are you using this information to create a robot design or just because? To simply asnwer your question, if you are using Inventor, LegoMindstormsmaniac has a whole collection of parts (sized, weighted, colored) for Inventor. You should contact him for more information.

Right I know he does (however, given the thread he posted, I don’t think he has the weights of hardware(?)). I don’t typically put nuts and bolts into Inventor because it would be too time consuming. Also, my desktop computer with which I was using Inventor crashed, so I haven’t been using Inventor recently. I’m just trying to make modifications to the robot we currently have built. But I’ll just do some calculations based on what I have.