Hey Chief Delphi,
as CAD Lead for this upcoming 2013/2014 season, we’ve started to design a pit made of pvc piping. I’ve just cadded all the fittings in creo 2.0 student edition because I just couldn’t seem to find any .prt files of pvc fittings.
We’re thinking of using a few pieces of clear acrylic or pvc in the structure, especially in the front to put some rope LEDs through the pipe! so far it’ll have eighteen 5’ pieces, twenty 4’ pieces, and nine 2’ pieces. The pieces combine with or without the two foot pipes to create an 8’x8’ or 10’x10’ pit.
Attached is a zip file of the fittings I cadded today including:
3-way corner connector
and a tee with side outlet
Soon I’ll upload the whole assembly including renderings!
If you have any additions, or critiques on my cad (:o), any comments would be appreciated!
We plan to use the front pipe as acrylic or clear PVC and threading RGB LED strips through and powered with an arduino. I cadded it all in creo, a PTC program. So far, we plan to make it out of 1-1/2" PVC pipe.
Please comment with ideas, critiques, or anything!!!
There’s no diagonal bracing of any kind in your design which means it will sway big time. You could use small diameter aircraft-type cable with turnbuckles to stiffen it up. A single cross piece across the front will sag if it’s plastic. Consider making up a truss so that it has more depth. How are you intending to hold the pieces of pipe into the fittings?
I have designed 27 pit designs for my teacher/coach and he had turned away every idea of mine. I have no more ideas left! Can you please share your cad files of your final design with me? And a list of materials and stuff.
First off, it looks pretty good, and you did a nice render! (I’m not really sure how the front corner managed to get cut off, but that’s a different thing)
Structurally, like George said, you definitely need some diagonal bracing in there. I would recommend doing this with sheets of plywood or something of the like attached to the PVC in the corners-- this will also give you a better place to mount lighting and such. You can also have a dedicated electronics panel for the arduino controlling the LEDS attached to one of these. When you’re adding lighting, make sure to plan out your wiring-- nothing is more irritating/dangerous than wires falling out all over the place.
I would also recommend having some sort of flat baseplates that can attach to the bottom of the structure. Team 2220 has a different type of pit (a very nice metal truss pit that one of our sponsors partially donated to us), and the steel baseplates are a huge part of keeping the structure stable.
My other recommendation is to plan for how you’re going to store, transport, and assemble the pit. Having some of the parts preassembled may allow you to save time on setup and also glue some of the joints, which will help with keeping everything together. Of course this comes at a cost of space during transport, but it’s definitely something to consider.
Overall, it looks like an awesome low-cost pit structure-- I hope I get to see it at Championships this year!
I do not have the cad for our pit on hand at the moment but here is a picture. It takes <25min to set up it is all folding on door hinges and fits in the back of a mini van(with out robot) its built to fit in a 10/10 but will go in a 8/8 if the pit must be reduced in. Made of wood and for the easy transport is on locking swivel wheels. We put up old banners to cover tools when we leave for safety reasons. [RIGHT][/RIGHT] http://lh5.ggpht.com/-ttK2BPbj2fU/UVzjIs8mWYI/AAAAAAAARvk/ExTV9oshQlA/s800/IMG_8471.JPG
It may be too late for this suggestion, as you have already put a considerable amount of work into drawing your pvc structure, but I would build this from electrical conduit rather than pvc. It is much smaller, a bit lighter, and even 1/2" conduit is considerably stiffer than pvc. Plus, with conduit you can carefully wrap whatever color of duct tape you wish around the pipe to make a very durable colored piece…pvc can be painted, but scratches if you look at it the wrong way.
I bet you could find CAD files for all the fittings from McMaster Carr.
Oh - one downfall - there does not seem to be “T” fittings for conduit, so you’d have to make something yourself.
First off make sure you follow all FIRST Rules for the pits. First has been known to change them from year to year. But if my memory is good you should be ok.
2nd. Have a budget, acrylic can run your cost up fast.
3rd. Remember the pits get crowded and thing’s get bumped into by humans and bots. You dont want your pit crashing down on you or others. The safety Advisers frown on this. ( I know I have been one).
As for your design I like it a lot, Iam not to sure on the stability of it. I think it will twist and wobble. Also are you going to glue any of the pieces together.
Because you don’t want any one bumping in to a section and having it all come down. If you chose not to use PVC cement I would come up with a cheap way to pin all the pieces together.
Also you are limited to only one power strip per pit so know your needs are for your LED’s. Alot of teams use spare Bot batteries.
I’m not sure exactly what you mean by this, but what is provided in terms of electricity varies based on event. Check with your local regional coordinator/planning committee to find out how many outlets, etc. will be available for you at your event.
As always, make sure that your pit is electrically and structurally safe. This may mean asking a professional to come in and examine your pit (if you don’t have someone with a lot of electrical/safety knowledge on your team).