View Full Version : PvC air rams???any-one here make one?
Northern Touch
03-05-2007, 11:36 AM
I have seen a couple of how toos out there for this and thought I might give it a try, while I'm building my first few penumatic props....I'm still new to this stuff and wondered if any body had any good feed back...
jrzmac
03-05-2007, 12:33 PM
i made this a few years ago http://www.vilethings.com/simple_pop_up_introduction.htm
but traded in the pvc ram for a real cylinder. with all the money you're gonna wind up spending to build one out of pvc, you might as well buy a bimba or something from e bay. i just got a 14" stroke 3/4" bore for $17.00.(10.00 s+h). with the pvc, you'll probably wind up spending 20.00 for all the parts, connectors, paint and so on. then you have the safety thing that i'm not even gonna touch right now, but for $27.00, i think it's worth it knowing that its safe and reliable. something like this maybe: http://cgi.ebay.com/BIMBA-STAINLESS-AIR-CYLINDER-2-IN-BORE-24-IN-STROKE_W0QQitemZ250089119964QQihZ015QQcategoryZ670 10QQrdZ1QQcmdZViewItem
GraveDiggerGreg
03-08-2007, 10:09 PM
agree on safety, but your item example sold for $80 bucks... 42 win and 38 shipping!
Frighteners Entertainment
03-08-2007, 10:12 PM
Ouch, expensive!!
I've been using door closers since 2000, well 2 to be correct, for opening and closing the crypt doors.
You just need to be careful on your pressures and the amount of weight you intend to move.
All the rest are bimba cylinders for the props.
Brad Green
03-08-2007, 10:55 PM
I've built several props using pvc rams, and have since switched each and every one over to real rams or home-built door closers. The pvc ones always tend to be very hard to maintain a good seal, causing them to leak alittle at first and alot later on. Second, if you build it secure enough to handle the load, you really don't have any internal access to re-lube (you need glycerin to coat the "seals" to get it to hold air) or to make any repairs/adjustments. Also bear in mind the pressure rating on the side of pvc piping is for water, air is a different animal altogether. Last thought on the matter, if exposed to very cold weather during use, pvc can go off like a grenade when hit with air. You may have to keep an eye on several auctions, but you can get cylinders at good prices (I just got a 2" dia., 12" throw for $20, shipping and all), or try your hand at a door closer, they're pretty simple and alot safer!
bourno
03-09-2007, 12:18 AM
I use the real cylinders as well. I don't have any experience on making homemade ones though, but I do see their value for some that want to go that route.
As for ebay, that is where I have gotten most of mine. Patience and sniping is a virtue :D For the most part, I have done well at getting most of the cylinders on ebay at a very good price. If they go high, then they won't be shipped to my address, lol.
propmastertucson
05-28-2007, 09:59 AM
A few years ago I built a couple of props that I call “The Boy’s” They are constructed from PVC an have worked well. They run at around 25-30 psi. They are very easy to put together and not too costly. The valve cost more than the prop.
http://i18.photobucket.com/albums/b121/pmtucson/P1010064.jpg
http://i18.photobucket.com/albums/b121/pmtucson/P1010061.jpg
http://i18.photobucket.com/albums/b121/pmtucson/P1010068.jpg
I made them so they would leak. I did not want any problems. I also used the plastic string that is used on a weed eater to stop the ram before it tops out.
PMT
gadget-evilusions
05-29-2007, 01:24 PM
Please use real cylinders. Like everyone said, ebay is a great source if you don't have the money to go new. When PVC is repeatedly pressurized and depressurized it weakens considerably, and when it finally goes will shoot nice shrap pieces of plastic everywhere. Serious injury can occur, even at low pressures.
ScareShack
05-29-2007, 10:12 PM
Please use real cylinders. Like everyone said, ebay is a great source if you don't have the money to go new. When PVC is repeatedly pressurized and depressurized it weakens considerably, and when it finally goes will shoot nice shrap pieces of plastic everywhere. Serious injury can occur, even at low pressures.
I have to agree with this statement. Think safety. PVC may work, but can be dangerous as compressed air is nasty. Take it from me, i was in the hospital for a compressed air accident 2 years ago on my hand.
My 2 cents, use real cylinders....many have had luck with homemade, but keep in mind, accidents do happen, as an accident is just that.
dave the dead
05-29-2007, 10:19 PM
I made one a few years ago, and was totally unimpressed with the performance. It was a maintanence nightmare, didn't pop nearly as quick as I needed for the effect, and ended up blowing the top cap of the ram clean off.....I've used door cylindars many years, and have a bike pump safely inside a trash can trauma (which has been flawless).....
IMO, Northern Touch.....don't waste the time or money on making a pvc cylindar.....
Northern Touch
05-30-2007, 12:18 AM
thankz guys for all the info I think i'm dumping the whole pvc thing I have been playing around with screen door closer's and diff. set-ups and I think all just stick with that for now...I found this site lawnscare.com/and deviousconcoctions.com has lots of cool ways U could incorperate a screen door closer
spokanejoe
06-15-2007, 08:35 PM
OK I didnt listen to all your advice and went ahead and made my own plastic pipe cylinder. It takes over 85 lbs to make it move and that scares me.
I want to get a decent cylinder and have been to Bimba and clippard.com but am OVERWHELMED....can anyone get me an site address that may have fewer choises so I can continue to make my vilething simple popup?
I would like to get something that would rise 2ft like the plastic one was supposed to. But everything I see is way too costly. Can anyone advise me on how to engineer it so it will still rise 2 ft. but use a cylinder with a smaller throw?
I am open to all suggestions but I am basically cheap. LOL Any help will be appreciated.
Why not use real cylinders? You can buy used ones very cheaply on eBay. Look for someone selling several cylinders in a single lot. I have bought dozens of them that way, generally for a few dollars a piece.
-Brian
Sickie Ickie
06-28-2007, 01:33 AM
spokanejoe, gadget has some great ideas on throws that I'm sure would work well for you.
TwistedDementia
06-28-2007, 01:45 AM
I've purchased over 50 pneumatic cylinders (Bimba, SMC, ect.) off ebay, new and used, along with all kinds of valves and hoses ect., and have to say it the way to go, just keep in mind it takes time and patience to find a good deal on ebay but they are out there. So good luck hunting if that's the route you go!
gadget-evilusions
06-28-2007, 07:47 AM
OK I didnt listen to all your advice and went ahead and made my own plastic pipe cylinder. It takes over 85 lbs to make it move and that scares me.
I want to get a decent cylinder and have been to Bimba and clippard.com but am OVERWHELMED....can anyone get me an site address that may have fewer choises so I can continue to make my vilething simple popup?
I would like to get something that would rise 2ft like the plastic one was supposed to. But everything I see is way too costly. Can anyone advise me on how to engineer it so it will still rise 2 ft. but use a cylinder with a smaller throw?
I am open to all suggestions but I am basically cheap. LOL Any help will be appreciated.
What kind of pop up? I have plans for a few pop ups that I don't mind sharing. Some give two feet of travel with much smaller cylinders.
The Haunter
07-18-2007, 02:56 PM
Posting to an old post but i got all my cylinders from the maintinance man at the factory my brother works at .They were going to throw them out.
Death Master
07-18-2007, 09:28 PM
I used to make mine out of steel pipe and rod but after the 1st year the PM was a nightmare, they leaked, and when the TOT traffic got heavy they started to blow by the seals, just when I need them the most. I make a lot of pneumatic animatronics and I use bimba cylinders you cant go wrong. they last a long time, and are reliable. USE REAL CYLINDERS, you wont be sorry. there are a lot of sites that show you how to get a lot of throw for a small stroke cylinder.
Haunted Wolf
07-19-2007, 10:54 AM
What kind of pop up? I have plans for a few pop ups that I don't mind sharing. Some give two feet of travel with much smaller cylinders.
Can you share all of them? I am looking for some ideas to use in a new area of my yard and I would like to step up the startle factor in this part of my haunt.
Thanks!
gadget-evilusions
07-19-2007, 08:05 PM
I can't share plans for all my props, i have a business to run. If you see one somewhere let me know and i am sure i have plans for one laying around here.
Haunted Wolf
07-20-2007, 12:24 PM
I can't share plans for all my props, i have a business to run. If you see one somewhere let me know and i am sure i have plans for one laying around here.
I guess that should have been a no brainer...doh! I'll do some browsing and get back to you.
HalloweenZombie
07-24-2007, 01:08 AM
I've made a PVC air cylinder. I never had a problem with it exploding or anything, but it did stop working half way through the big night when it got a little cold out. Not freezing, but cold enough to lock up the cylinder. I don't think my prop posed a danger to the general public, but it wasn't reliable. I've learned to use real pneumatic cylinders and aluminum stock. If time is money, then the real thing doesn't cost anymore than the PVC stuff does.
redg8r
10-19-2007, 11:36 PM
I reluctantly agree, I say reluctantly because the initial concept & availability of the material is so attractive.
Ive used PVC rams for the last 2 seasons & even though I put alot of added effort to make them function safely & as I intended, they always fail when needed most.
I tried making an additional pair this year & gave up. The hardest part is safely limiting the travel. I wouldn't rely on yard trimmer string to stop a 24" ram under 30psi. I used 3 strands of 65lb spiderwire braid (fishing line).
After the previously built rams failed to operate after a year in storage I scrapped them all in lieu of heavy duty door closers, which I'm not 100% happy with either. so regardless to say, next year will debut new bimbas.
Good luck & thanks for the input all.
airscapes
10-20-2007, 12:55 AM
Made one of these prop http://www.vilethings.com/simple_pop_up_introduction.htm
about 4 year ago now.. pcv ram is doing great, last year I took it apart and adjusted the seal for a tigher fit and lubed with Graphite. Travel is contorled in the desige of the pludger/pushrod with screws in the wood dowl reinforce pushrod . These hit the cap at the end of the travel, as well as the elastic which operate the props hands. Runs at about 50-60 PSI and is THE most popular prop with the best and funniest scares. It has sent grown people running (just the other night) for the car!
Where do you get 24-28" industrial Rams for $50.. ..
Now watch, it is probably reading this and will fail tomorrow:googly:
Right click save and then play
this is a little kid setting up his mom to be scared... evil child.. gota lovem!
http://65.78.32.161:666/halloween-2004/Quick-Time/Popupguy_scared.MOV
harryhood
11-02-2007, 01:39 PM
eh, they're not so bad if you just put a little effort into them. steve at terrorsyndicateproductions.com makes a nice little book that explains his way of making both the door closer ones and PVC. I ran two PVC and one door closer this year and they weren't bad. The advantage of the PVC is you can make them as large as you want. I built two with a 4 foot stroke, those typically would run a few hundred bucks minimum. I used it to drop bugs and a foam girl from the ceiling. Worked great! You just have to put a PSI regulator on there so they don't go flying out the shaft.
Hellspawn
11-02-2007, 02:31 PM
If you need to get 24'' of throw, you can get that with a small stroke cylinder using a 4 bar mech, dont quote me, but im sure its possible
I used a door closer with my body slinger with a 4 bar mech, I think the door closer has approx 5'' of throw and I can push my corpse up and out a good 18-24''
The problem you would run into is the farther you want to bar to lift, the closer to the frame you would need to place the cylinder which equals more force to move (air pressure).
now, if your using a commercial cylinder, I wouldent worry too much about the airpressure, but I get nervous pushing too much pressure through my doorclosers.
get a cylinder with 6'' of stroke and 1'' diameter rod and you could lift just about anything with the right pressure and still sleep at night.
Revenant
11-03-2007, 03:13 AM
Buy a copy of Animatronics: A Guide to Animated Holiday Displays by Edwin Wise. He not only explains the basics for the levers and mechanisms you need to amplify the throw of a cylinder for animation, but gives diagrams and formulas you can use to precisely build something that gives the distance, movement paths, and size you need. It's the best book that exists on the subject that isn't written for the industrial engineer.
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