[FTC]: 80/20 and open builds mounting on tetrix

[robot]

So we have attempted to mount our 80/20 lift onto tetrix but the metric screws don't fit anywhere. I've taken pictures of teams that stick a screw with a rather large end cap into the tetrix axle hole, but all of the end caps of our screws are too small for that to work.

Same thing with openbuilds, unfortunately.

[ehochstein]

Have you tried Rev Extrusion from AndyMark?

http://www.andymark.com/product-p/am-2915.htm

[robot]

Originally Posted by ehochstein

Have you tried Rev Extrusion from AndyMark?

http://www.andymark.com/product-p/am-2915.htm

I saw them at worlds in their booth. They're really lightweight, might have some good uses, but no, we have not attempted anything with these. We're working on 2 lifts right now and I think that's enough

p.s. the 80/20 we have is the smallest available, i think 20mm, and we use delrin sliders for 80/20 which may or may not work well

[ehochstein]

Originally Posted by robot

I saw them at worlds in their booth. They're really lightweight, might have some good uses, but no, we have not attempted anything with these. We're working on 2 lifts right now and I think that's enough

p.s. the 80/20 we have is the smallest available, i think 20mm, and we use delrin sliders for 80/20 which may or may not work well

We used 80/20 on our robot this year as a linear lift. We ended up waterjetting custom aluminum pieces to attach it. I can't think of any simple ways to attach 80/20 to tetrix pieces off the top of my head. We did attach two tetrix worm gear boxes directly to the 80/20 but ended up using 1/4-20 bolts drilled through the 80/20 as we needed rigidity in its construction.

Sorry I can't be of more help. I can share our CAD files with you, if you'd like?

[IceStorm]

Not to hijack the thread but had a conversation in length about the REV line with one of there people on sat in there booth. They are coming out with all sorts of stuff soon for the 15mm line. They worked with a few teams this season to develop it. Can't wait to get my hands on it. Love the versatility of 80/20 but the smallest they have is still overkill in weight. The REV stuff is super lightweight in comparison.

[Sasha]

We are using 20mm series of t-slot aluminum. To attach tetrix pieces to them, we put a 6-32 keps nut (used in tetrix system) in the t-slot - it just fits (wth some effort). After this, we attach the tetrix pieces using regular 6-32 screws. When we need a stronger connnection, we just drill out the hole in tetrix piece and use the metric (m5) screw with the t-slot nut to attach.

However, most of our robot uis built out of t-slot profile; we do not use that many tetrix pieces.

FYI: adafruit also sells 15-mm t-slot profile:
http://www.adafruit.com/products/1275
Haven't tried it myself yet

[robot]

Just simply wondering how to attach our lift/s to tetrix because we seem to have hit a brick wall

[ehochstein]

Originally Posted by robot

Just simply wondering how to attach our lift/s to tetrix because we seem to have hit a brick wall

What size 80/20 are you using? Could you post a picture of what you are trying to do for us? Would help loads!

[budman]

Yes, please post a picture. We used lots of 80/20 this year on our robot due to the COTS rule change. Excited to see teams using other materials like 80/20 and REX. Did not know about the OpenBeam from AdaFruit...thanks Sasha.

[lylecheath]

I've got it!

This is how we did ours, pretty painless, you won't need to buy anything new. We used the axle holes with the screws that it seems that you already have. To make everything align, you need to cut a brass bushing such that the barrel is thinner than a flat tetrix piece. Now you can thread your screw into this brass bushing, and it will allow you to attach directly, no fuss. Also everything aligns perfectly.

Good luck!
-Lyle (4029)

[Greg Needel]

Hey All,
This is something that we have done our best to address with the 15mm REV extrusion. http://www.revrobotics.com/product/15mm-extrusion/

Our small extrusion uses 3 mm hardware, The small holes in Tetrix are 3.7mm in diameter which is a bit larger than a standard fit (3.3mm( hole for 3mm hardware. In our testing of this adaption, 2 screws placed in any of the small holes along a rail makes a firm connection. We have suspended a 30lb load from the bracket without even a hint of movement (we can test to failure if people want).



This summer we are going to be rolling out a whole bunch of new support brackets, hardware, and accessories specifically designed with FTC in mind.

If you have any questions I am always available.


Thanks,

Greg

[robot]

Ah I've got it. For 80/20 we simply slid a tetrix nut into the t-slot (for 20mm)

for openbuilds, the end of the v-slot screw is larger than the tetrix axle hole IIRC, and we just screwed it into a t-nut.

Thanks everyone!

[OllieK]

If your team has access to an accurate cutting machine (table saw or mittre saw), drill, and tapping tools, it is feasible to create the missing mounting components from standard aluminum bars.

The instructions can be found at
http://ftcforum.usfirst.org/showthre...hole-locations





Cheers, Ollie