Author Topic: Why not use PVC?  (Read 5579 times)

Ron

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Why not use PVC?
« on: May 16, 2011, 08:19:24 AM »
Simple.

CPVC is sized in a manner that lets you "nest" pipes with ease without having to resort to the larger sizes of PVC that would be necessary to accomplish the same task.

On my Crow's, I've always used 3/4 200PSI PVC as the outer most control rod, and used CPVC and dowel rods for everything else.

SynaMax

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Re: Why not use PVC?
« Reply #1 on: May 16, 2011, 03:29:57 PM »
There's an aspect of this that still doesn't make sense to me.  I'm able to "nest" a 1/2" 315PSI into a 3/4" 200PSI just fine.  It spins freely and everything.

The reason why I bring this up is because I want to build a bot as if it were built by BBI.  I did a lot of research and noticed that the coupling in Crow's pin is sized just like a 1/2" PVC coupling or tee (however, I think the 3/4" CPVC tee would make a good substitute).


The top one is 1/2" PVC.  The bottom is 1/2" CPVC.
Sci-Fi era Crow

CC era Crow

Now, here's a comparison with the CPVC


Forgive me if I'm hijacking your thread, Ron.  I hope you don't mind.  

Obviously, this is BBI's way of making the bots...which means diddly-squat.  In the end, it's your bot; make your own choice. :)

Ron

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Re: Why not use PVC?
« Reply #2 on: May 16, 2011, 09:54:02 PM »
Part of the issue is the amount of material that you're removing from the neck of the pin.  A hole gauged for a 1/2" CPVC T is going to have more 30+ year old plastic around it in case you accidentally bump the end of the beak in a "flexing motion."  What might have just been a scare, is now a rebuild.

Plus it's the way I've always done it ;)



This works really well...

However, it's important to always stop and put things in perspective every once in a while...  take this for example:



Look at the paint on the back of the pin.  This is a close up... IN THEIR MOVIE. ;)


SynaMax

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Re: Why not use PVC?
« Reply #3 on: May 17, 2011, 12:19:52 AM »
Part of the issue is the amount of material that you're removing from the neck of the pin.  A hole gauged for a 1/2" CPVC T is going to have more 30+ year old plastic around it in case you accidentally bump the end of the beak in a "flexing motion."  What might have just been a scare, is now a rebuild.

Yes, I totally agree.  I grabbed some newer Toys R Us bowling pins for those pictures and realized that the hole for the 1/2" is huge.  Perhaps that's why they used 1/2" couplings instead of tees so that they only make one big hole in the bottom of the pin and a smaller top hole for the pipe that sticks through the soap dish.



Look at the paint on the back of the pin.  This is a close up... IN THEIR MOVIE. ;)

Hahahaha, yeah, I love that paint job. XD  I found this lovely Crow paint job on the Poopie tape. lol


Ron

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Re: Why not use PVC?
« Reply #4 on: May 17, 2011, 08:40:42 AM »
The scifi era lighting (ie: MAKE EVERYTHING BLUE!) really shows off the paint flaws.  You know how Testors runs like a race horse and pools making these darker bits in your paint at times?  Well, there's an episode where Crow looks like a melting candle due to all the runs.  Other times, you can see sheets of the paint that dried thicker and Patrick just said "fudge it."

Evil Bob

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Hijack#2
« Reply #5 on: May 17, 2011, 09:17:10 AM »
I love that scene from the movie! It shows Crow tilting his head back and looking up and you can read "Tuppercraft" on his shoulder.

askbotboy

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Re: Why not use PVC? I must show you mine! (Heh)
« Reply #6 on: May 17, 2011, 04:19:53 PM »
I have stayed out of this discussing for a while now- only because I am lazy and haven't wanted to look through my old photos, etc. BUT- I think I have the BBI method- and I may be totally wrong. And if I am I will eat a bug. (of my choosing and when no one is looking) Because I held a few Crows in my hands at Best Brains, and also by looking at old photos, post cards video etc. - I think The bottom of the "e" pin has a 1 inch hole drilled into only the bottom half. With a little X-Acto scraping, a 1/2 inch PVC, straight coupling is forced snuggly into the bottom of pin. Then on the pin top side, I use a 1/2 inch hole saw with a 2 inch section of 1/2 inch PVC inserted into the top. I use a little modeling putty (Milliput) and make a nice smooth edge and prime and paint. Sorry, these stills are from my Crow Video- so not as clear as some reference. But you get the idea.

SynaMax

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Re: Why not use PVC? I must show you mine! (Heh)
« Reply #7 on: May 17, 2011, 08:56:54 PM »
I have stayed out of this discussing for a while now- only because I am lazy and haven't wanted to look through my old photos, etc. BUT- I think I have the BBI method- and I may be totally wrong. And if I am I will eat a bug. (of my choosing and when no one is looking) Because I held a few Crows in my hands at Best Brains, and also by looking at old photos, post cards video etc. - I think The bottom of the "e" pin has a 1 inch hole drilled into only the bottom half. With a little X-Acto scraping, a 1/2 inch PVC, straight coupling is forced snuggly into the bottom of pin. Then on the pin top side, I use a 1/2 inch hole saw with a 2 inch section of 1/2 inch PVC inserted into the top. I use a little modeling putty (Milliput) and make a nice smooth edge and prime and paint. Sorry, these stills are from my Crow Video- so not as clear as some reference. But you get the idea.

Thanks a lot for the pictures and tutorial, Gary!  I agree, it looks like it's a 1/2" coupling in the bottom of the pin.  Do you happen to know where I can find 1/2" and 1" hole saws?  I didn't see any the last time I looked at Lowe's.

Also, do you happen to know when you'll be releasing your Crow build video?

Derek

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Re: Why not use PVC? I must show you mine! (Heh)
« Reply #8 on: May 17, 2011, 09:14:51 PM »
I think The bottom of the "e" pin has a 1 inch hole drilled into only the bottom half. With a little X-Acto scraping, a 1/2 inch PVC, straight coupling is forced snuggly into the bottom of pin. Then on the pin top side, I use a 1/2 inch hole saw with a 2 inch section of 1/2 inch PVC inserted into the top. I use a little modeling putty (Milliput) and make a nice smooth edge and prime and paint.

This is more or less the method I use as well... minus the modeling putty and some of the tools Gary uses... but the same means are achieved. The end results look very screen accurate.

-Derek

askbotboy

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Re: Why not use PVC?
« Reply #9 on: May 17, 2011, 10:39:03 PM »
Hey Max, I did find my hole saws at Home Depot. Look near the door hardware area- I think these are used to start holes for some door locks etc.
Amazon had this kit-http://www.amazon.com/DEWALT-D180002-Standard-Electricians-Bi-Metal/dp/B00005LF01/ref=sr_1_11?s=power-hand-tools&ie=UTF8&qid=1305689866&sr=1-11

A bit expensive though!

Ron

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Re: Why not use PVC?
« Reply #10 on: May 18, 2011, 09:08:47 AM »
What is the suggestions on the rest of the tubing?

Ron

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Re: Why not use PVC?
« Reply #11 on: May 23, 2011, 03:44:12 PM »
So no one knows? :)

crowtrobotfan4

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Re: Why not use PVC? I must show you mine! (Heh)
« Reply #12 on: July 31, 2012, 01:40:16 AM »
I have stayed out of this discussing for a while now- only because I am lazy and haven't wanted to look through my old photos, etc. BUT- I think I have the BBI method- and I may be totally wrong. And if I am I will eat a bug. (of my choosing and when no one is looking) Because I held a few Crows in my hands at Best Brains, and also by looking at old photos, post cards video etc. - I think The bottom of the "e" pin has a 1 inch hole drilled into only the bottom half. With a little X-Acto scraping, a 1/2 inch PVC, straight coupling is forced snuggly into the bottom of pin. Then on the pin top side, I use a 1/2 inch hole saw with a 2 inch section of 1/2 inch PVC inserted into the top. I use a little modeling putty (Milliput) and make a nice smooth edge and prime and paint. Sorry, these stills are from my Crow Video- so not as clear as some reference. But you get the idea.
can u send me the crow video i need it to build him