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-   -   VersaFrame by VEX Robotics (http://www.chiefdelphi.com/forums/showthread.php?t=131601)

JesseK 21-12-2014 08:41

Re: VersaFrame by Vex Robotics
 
Quote:

Originally Posted by Monochron (Post 1415539)
Maybe I am undervaluing the usefulness of that hole pattern, if so could someone enlighten me? I see it as something that can save you some measuring when trying to line things up, but can also cause you to waste time cutting the tubing so the holes line up perfectly, and can make mounting near a hole a serious pain as it ruins the strength of the metal at that point.

The hole pattern would immediately save an hour or two of drilling tubes/plates while simultaneously guaranteeing precision alignment with the VEX gussets. This compounds later down the road - imprecise rivet holes (1)require the piece to be re-made or (2) are more likely to fail, causing heartache during a match in addition to having to re-make the mechanism.

Depending on the game and a team's design process, the hour or two is paramount to quick iteration, which then translates into getting a working design earlier in the season. 2014 really required fast iteration of a physical machine if a team did catapults. 2013 probably didn't require too much physical iteration except at the disc transition points. 2012 didn't require any physical iteration for the main game piece (since it was so squishy), but required a lot of iteration for the bridge lowering. And so on ...

Chris is me 21-12-2014 10:40

Re: VersaFrame by Vex Robotics
 
Quote:

Originally Posted by Monochron (Post 1415539)
Maybe I am undervaluing the usefulness of that hole pattern, if so could someone enlighten me? I see it as something that can save you some measuring when trying to line things up, but can also cause you to waste time cutting the tubing so the holes line up perfectly

It's really easy to do this. We just made a little jig that anyone with a CNC mill, 3D printer, router, or any number of machines could make. A little flat plate 2" long, 1" wide, with two hole-sized nubs sticking out of it 1" apart. Just place this in your VersaFrame part and mark the piece at the edge of the jig. If you can't make this jig, just use a VersaChassis gusset, a few (non-installed!) rivets, and a steady hand to do the same thing.

Quote:

and can make mounting near a hole a serious pain as it ruins the strength of the metal at that point.
This really isn't the case at all. A hole less than 1/4" in diameter is going to have minimal impact on a beam's resistance to bending, especially since the hole is not on the face normal to the hole. There is no noticeable difference in strength, certainly not even close to "ruining" the part.

Monochron 21-12-2014 12:31

Re: VersaFrame by Vex Robotics
 
Quote:

Originally Posted by JesseK (Post 1415590)
The hole pattern would immediately save an hour or two of drilling tubes/plates while simultaneously guaranteeing precision alignment with the VEX gussets. This compounds later down the road - imprecise rivet holes (1)require the piece to be re-made or (2) are more likely to fail, causing heartache during a match in addition to having to re-make the mechanism.

An hour or two of drilling? Maybe if I was trying to replicate the hole pattern, but I just don't see that much time used in putting a couple mount holes in tube. The time you lose cutting the tube so that multiple holes line up with multiple other holes would mitigate a lot time saved drilling in my opinion.

I could see the benefit of guaranteeing alignment with gussets, but again, only if you cut to the proper length. It is definitely a time saver to line up with gussets, no doubt, but you lose the ability to just get a length, clamp it to another piece, and drill right through.

Quote:

Originally Posted by Chris Is Me (Post 1415590)
This really isn't the case at all. A hole less than 1/4" in diameter is going to have minimal impact on a beam's resistance to bending, especially since the hole is not on the face normal to the hole. There is no noticeable difference in strength, certainly not even close to "ruining" the part.

My bad, replace the word "metal" with "mount hole". We tore the metal in a couple places our first year by having to drill multiple holes close to each other on some sheet metal. The metal itself held up, but the bolt in the correct hole tore its way over to a nearby hole and came out. That is what I was referring to.

JesseK 21-12-2014 13:39

Re: VersaFrame by Vex Robotics
 
Quote:

Originally Posted by Monochron (Post 1415626)
It is definitely a time saver to line up with gussets, no doubt, but you lose the ability to just get a length, clamp it to another piece, and drill right through.

This, in my experience, has been fine for everything but a drive train. Getting 4 rails to line up squarely (< 1/32" deviation in the cross-diagonal measurements) using only gussets takes a LONG time. Well, maybe there's a better way than how we used to do it. I'm all ears for that, but it has to be square.

Good point on the cut-to-length though. It's a given for my team and often overlooked in discussions.

Chris is me 21-12-2014 16:50

Re: VersaFrame by Vex Robotics
 
Quote:

Originally Posted by Monochron (Post 1415626)
My bad, replace the word "metal" with "mount hole". We tore the metal in a couple places our first year by having to drill multiple holes close to each other on some sheet metal. The metal itself held up, but the bolt in the correct hole tore its way over to a nearby hole and came out. That is what I was referring to.

I guess I'm confused as to why you're not using the existing hole pattern to mount stuff, with the possible addition of half-inch holes in order to install more rivets. With the 1x1 tubing we did have a lot of wear problems with bolting through, mostly due to the incredibly thin wall of such a tube - these problems did not persist when stepping up to 1/16 or 1/8 wall tube.

If you're not really using the hole pattern, there is a lot less reason to buy the VersaFrame tubing profiles.

Quote:

Originally Posted by JesseK (Post 1415650)
This, in my experience, has been fine for everything but a drive train. Getting 4 rails to line up squarely (< 1/32" deviation in the cross-diagonal measurements) using only gussets takes a LONG time. Well, maybe there's a better way than how we used to do it. I'm all ears for that, but it has to be square.

Good point on the cut-to-length though. It's a given for my team and often overlooked in discussions.

We have a lot more success by clamping the frame square using large C-clamps before riveting. Still takes awhile to get it square, but it holds very nicely once its there allowing for easy mass riveting.

billbo911 21-12-2014 18:17

Re: VersaFrame by Vex Robotics
 
Quote:

Originally Posted by Chris is me (Post 1415690)
...We have a lot more success by clamping the frame square using large C-clamps before riveting. Still takes awhile to get it square, but it holds very nicely once its there allowing for easy mass riveting.

This is also the approach we use. We will get it close by first dropping a few rivets into their holes, but not popping them. We then use large cabinet clamps to apply a small amount of pressure to the frame. Then using light mallets, we tap the frame pieces until everything is square and flat. We then tighten the clamps to hold everything secure. Once we have double checked all measurements and are satisfied they are right, we go to town on setting all the rivets.

This process takes a bit longer, but taking the time to do it right the first time is still way faster than having to re-do it again and again.

Bonzabonz 23-12-2014 18:15

Re: VersaFrame by VEX Robotics
 
Is it possible to use bolts as opposed to rivets when connecting the gussets to the metal tubing, or is there a major drawback somewhere when using bolts?

Oblarg 23-12-2014 18:17

Re: VersaFrame by VEX Robotics
 
Quote:

Originally Posted by Bonzabonz (Post 1416519)
Is it possible to use bolts as opposed to rivets when connecting the gussets to the metal tubing, or is there a major drawback somewhere when using bolts?

Be careful not to crush the tube by overtightening, especially with the .04'' stuff. It's shockingly easy to do. But, yeah, you can do it.

Chris is me 23-12-2014 19:31

Re: VersaFrame by VEX Robotics
 
Quote:

Originally Posted by Bonzabonz (Post 1416519)
Is it possible to use bolts as opposed to rivets when connecting the gussets to the metal tubing, or is there a major drawback somewhere when using bolts?

Bolts can loosen, and generally bolts have a bit more play in the hole than rivets. They also weigh more. But other than that, they're fine. It's mostly just user preference.

mrmummert 23-12-2014 20:03

Re: VersaFrame by VEX Robotics
 
Hello...

1610 used the Versa chassis for the first time this past year and we
did pretty well with it (on winning alliance at VCU, Finalist at Chesapeake
and a Quality award at Chesapeake basically because the robot ran so well). The
1x2 held up well. We used that for our basic frame including a practice bot.
We used the thin 1x1 for our arm but looking back i wished we had used the 1x2 for that.
We were able to have the basic frame built and running in a couple days. The biggest
drawback we had was using all the pop rivets. We're planning on using
it again depending on the game and are looking into a Pneumatic pop rivet gun.

Team 2363 used it also and did very well (winners at Chesapeake,
winning alliance on Galileo) They used the 1x2 for their arm and it
held up much better than the 1x1 we used.

notmattlythgoe 29-12-2014 08:02

Re: VersaFrame by VEX Robotics
 
Quote:

Originally Posted by mrmummert (Post 1416563)
Hello...

1610 used the Versa chassis for the first time this past year and we
did pretty well with it (on winning alliance at VCU, Finalist at Chesapeake
and a Quality award at Chesapeake basically because the robot ran so well). The
1x2 held up well. We used that for our basic frame including a practice bot.
We used the thin 1x1 for our arm but looking back i wished we had used the 1x2 for that.
We were able to have the basic frame built and running in a couple days. The biggest
drawback we had was using all the pop rivets. We're planning on using
it again depending on the game and are looking into a Pneumatic pop rivet gun.

Team 2363 used it also and did very well (winners at Chesapeake,
winning alliance on Galileo) They used the 1x2 for their arm and it
held up much better than the 1x1 we used.

We actually just used 1x2 stock, not the versa tube.

TCMJ1816 29-12-2014 23:11

Re: VersaFrame by VEX Robotics
 
We've been prototyping with WCD using the Versa Frame this off season. The assembly of the frame itself has been a dream, so easy. We haven't had any issues with the strength of their 2X1 tube. We hope to use it very extensively this next year, It sped up the build process while maintaining a very high level of accuracy.

Coach Norm 30-12-2014 00:40

Re: VersaFrame by Vex Robotics
 
Quote:

Originally Posted by Chris is me (Post 1415690)
We have a lot more success by clamping the frame square using large C-clamps before riveting. Still takes awhile to get it square, but it holds very nicely once its there allowing for easy mass riveting.

We used Versa Frame last year and love the way it allowed for not only prototyping but also for our actual robot.

For those teams that are using rivets, you may want to look into using Clecos. Check out this link here: http://www.mcmaster.com/#5099a34/=v8rnw9 and Cleco pliers: http://www.mcmaster.com/#5099a51/=v8rphz
. These will allow you to use an existing hole or pattern not only to drill or to rivet. We have used these for several years to assist with mounting bumpers as well.

asid61 30-12-2014 01:13

Re: VersaFrame by Vex Robotics
 
Quote:

Originally Posted by Chris is me (Post 1415690)
We have a lot more success by clamping the frame square using large C-clamps before riveting. Still takes awhile to get it square, but it holds very nicely once its there allowing for easy mass riveting.

This is what we do. To get it square, we use the bellypan as a reference to align all the 2x1. We have some 36" steel rulers graduated in 0.01" increments, so we use those as a good gauge of the length of the 2x1 when we cut it.
Generally for most/all of our gussets we just cut and drill the gussets on a drill press and bandsaw. Then we clamp it to the 2x1 and drill through.


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