SpudFiles

I'm still not convinced that cellular core abs is the way to go, but it does have its strong points. This web page has a very interesting comparison of the two materials.

Material Properties: ABS Versus PVC Schedule 40 Pipe
A 2" PVC Schedule 40 pipe has a pressure rating of 280 PSI. At 90 degrees F this should be derated to 75% of maximum, or 210 PSI. This rating applies to pressurization with water, and does not include shock. For water applications, the pipe is derated a further 72% to cover surge or water hammer conditions. This puts the rating at 150 PSI. Most of the larger pipe sizes have lower pressure ratings. PVC pipe degrades quickly when exposed to sunlight. This is not covered in the specifications that I found. In my experience, full sunlight does tremendous damage to PVC Schedule 40 pipe. For example, sunlight can cause failures in pipes that are typically carrying 40 PSI water.

ABS Versus PVC for Spud Gun Construction

Don't use ABS for the chamber, no matter what they say, it's not made for continuous pressure, it's greater at absorbing very high pressure from oxy\acetylene (sp?) combustions for a few times, but it always wears out...

It has a high tensile strength, but I can tell that my ABS cannon is weakoning after me shooting it soo many times (thousands), but It still has some positives...

It's light so if your a complete wimp you can carry it longer than heavy PVC
But if your a wimp you probably shouldn't make spud guns

It's very corrosive resistant and can take chemicals in it that PVC cant...

I say this

ABS for Barrels = great (reduced weight, but bends)
ABS for Non-Propane Combustions = ok for a while (from my experiance)
ABS for Propane Combustions = iffy
ABS for short use remote OXY\Acetylene = iffy (it will break)
ABS for Pneumatics = NEVER!
ABS for Hybrids = NEVER! (it is a fuel-added pneumatic, so obviously no)

PVC for Barrels = excellent
PVC for any combustion (propane and all) = great
PVC for OXY\Acetylene = NOOOO!
PVC for pneumatic = AWSOME!!
Sch 80 PVC for Hybrid = Yes

I'd use Sch 40 PVC over ABS anyday, even for my barrels, but I don't mind the extra weight, it's not like it's that heavy...

They make pressure rated ABS... its much more expensive that PVC, and rarer as well. But if you are able to find it, it is better than pressure-rated pvc

NEVER use cellular core ABS.

You are confusing cellular core with regular DWV, (drain), ABS.

You would not have shot your gun thoudands of times without it breaking if it were cellular core.

DWV ABS is great for combustions, even metered propane propelled ones. Failure characteristics are a lot better. SpudMonster's SpudMonster is an ABS gun, and has a 10' long barrel, and 3x24" chamber, is metered propane, and has a chamber fan. It has not failed.

Just have to use the right fittings and glue...

markfh11q you have no idea what you are talking about!

All DWV ABS pipe is cellular core!

No it's not, buddy!

I can go get a length from the front yard and snap a picture if you'd like. It's thinwall, but it'll serve this purpose.

Just hang on a second.

EDIT: Here they are. The pipe was split from storage under a 55 gallon drum full of aluminum cans, but it served it's purpose. The images are more than a little foggy because of the humidity, and it was starting to get dark.

<img src="http://i10.photobucket.com/albums/a123/ ... dgeABS.jpg">

<img src="http://i10.photobucket.com/albums/a123/ ... oleABS.jpg">

What the hell is that supposed to prove?!
You can't tell pipe is cellular core just by looking at it!
ABS is cellular core they don't sell pressure rated ABS!

Sigh....

SCH-40 DWV ABS is available quite frequently around here in SOLID lengths, not CELLULAR CORE. In fact, I have YET to unearth ANY cellular core ANYWHERE!!!! I don't see why my area should be any different than yours.

Plus, I am also operating off the fact that MANY people have used SOLID ABS in combustion guns, because of its more desirable failure characteristics. SpudMonster, for one, and some people I unearthed on Google USG specialized search.

I KNOW the pictures don't prove much. I'm going to take more in the morning. Macro setting zoomed on the pipe edge will reveal the nature of the pipe. SOLID pipe has lines and ridges left from cutting with a saw. Cellular core has soft edges, with little or no lines or ridges. And you can occasionally see a few of the "cells" in the edge. I have used ABS for a few of my pyro endeavors because I knew it didn't fragment so much as split under pressure.


CELLULAR CORE pipe is available in both ABS and PVC varieties, and is NEVER and acceptable material for any type of pressure use. People would not have ABS guns if all they made was cell-core.

I know you have a spudtech account. Look at SpudMonster's SpudMonster <a HREF="http://forums.spudtech.com/topic.asp?TO ... r">here</A>.

You have no idea what the hell your talking about!

The pipe being SCH 40 has absolutely NOTHING to do with it being pressure rated or not!

You even saying that SCH 40 means that it's not cellular core just shows that you don't know what your talking about!

And, to cap it all off, a little Googling turned up this little gem...

http://www.ppfahome.org/abs/index.html

To quote.

"...ABS pipe is available in solid wall and cellular core construction in Schedule 40 dimensions. These two forms may be used interchangeably for DWV applications."

So... <a HREF="http://www.geocities.com/markfandal/youlose.html">you lose</A>.


EDIT: and I didn't say SCH-40 to imply it's pressure rated!!!!! I AM NOT THAT STUPID!!!!! ALL MATERIALS FOR MY LAUNCHERS ARE CHARLOTTE TRU-FIT PIPING RATED DUALLY NSF-PW & NSF-DWV!!!!! Most people do not use pressure rated ABS. It is sold, but SOLID WALLED, SCH-40 ABS will not fragment, like unrated SCH-40 PVC, or any PVC, which evens it out, and makes it ideal for use.

So where do you buy your "Solid Wall" ABS at?

If you can show me a place to buy solid abs pipe I'll admit your right.

Sorry for double posting, but I believe this requires another post...

I mean no disrespect, and I don't want to start a pissing contest. I'm just trying to prove my point. Having things like "You have no clue what you're talking about" said to me when I speak the TRUTH, not some made-up B.S., makes me feel like I've gotta back up what I said. I'm not trying to get riled or anything, I'm just trying to prove my point.

EDIT: The ABS was bought at our Home Depot in 1995 when we moved here.

You guys sound like married couple lol

Yeah... the fierce arguing and the, "Okay, I'm sorry, I was just... blah blah...", match up perfectly.

I am just trying to prove a small point, though. ABS <I><B>is</B></I> available in solid wall, and in fact, is the only variation of ABS that is safe for combustions... except for pressure rated ABS, of course.

I'm sorry for the "You have no clue what you're talking about" comment.
Because you obviously do, and obvously more then I do in this case.

I agree that solid and even pressure rated abs pipe dose exist, but finding it is another story. All the stores I've been to and even places that I can buy 4" Sch. 80 PVC don't have and have never heard of solid abs pipe.