Useful Facts and Ideas for New Spudgunners *Update

by **draculon** » Sun Apr 03, 2005 1:28 pm

I don't belive that anyone has asked questions about this before, but someone will eventually. This is a topic to post the meanings of any pipe symbols or phrases and their explanations. I'll start.

NSf-PW: means that the pipe is pressure rated
XXX p.s.i.: the pressure the pipe is rated to
DWV: Drain, Waste and Vent: safe for Combustions.
Male NPT x Socket Weld: adapter with male threads that fits over a pipe by slipping on.
Female NPTx Socket Weld: opposite of male
NPT x spigot: fits into a couling, bushing, anything that joins pipe
PVC: Polyvinyl Chloride: standard pipe, pressure rated but can become brittle
ABS: Acrylonitrile-butadiene-styrene: good for combustions but not pressure rated, DONT USE IN PNEUMATICS!
Cell Core: Very Unsafe. I wouldn't recommend to use it in anything.

Painting Pipe: This is how I do it.
1. Sand all the lettering off with 220 grit sandpaper.
2. Clean pipe with medium strength lacquer thinner to remove dirt and grime and leave a more proffessional outcome.
3. Krylon Fusion works best for plastic, but ohers work well.
4. Apply paint by spraying 6-12 inches away from pipe. Take your time and don't try to cover the whole thing in one go. This will help to eliminate drips and runs.
5. After your first coat has dried, from anywhere between 12 minutes to an hour, repaint it.
6. Let it cure for at least 24 hours(on Fusion it says 7 days).
Congrats, you painted it!!
I wont post about solvent welding because DR has his own Sticky.

Pneumatic Gasses:
Regular Air: Standard propellant for pneumatic launchers. A bit heavier on the molecular level than other gasses, but is readily available and cheap.
Helium: lighter than air, is a good propellant. Joel claims to have broken the sound barrier by using helium as a propellant with the supah valve.

Safety: This is what you should do and not do. http://www.spudtech.com/content.asp?id=16

Common Comustion Fuels
Propane: Very powerful and efficient, requires precise metering though.
Wd-40: Almost useless now that the propellant has been cahnged to CO2, although the older cans will work (no blue dot on nozzle).
Right Guard: The primary fuel of spudguns. Cheap, efficient, but less powerful than propane.
Hairspray:The worst fuel possible. Gums up your chamber, a more reasonable altrnative is deodarant.
Acetylene: VERY, VERY powerful. The pressure spike cannot be handled by PVC. Not reccomended for use ever (by me, other people have different opinions).
Starter Fluid (Ether):Very powerful, but somewhat difficult to meter. A half second spurt should do the trick.

Reasons Your Combustion Doesn't Work
http://localhost/forums/viewtopic.php?t=9243 : This is a sticky by Plasticex, accesible on the main page of the Newbie Corner. IT's a really good interactive guide. If you're combustion isn't working, check here.

Soldering Copper
1. Light your propane torch (Bernzomatic, etc).
2. Apply flux to the pipe to be inserted into the fitting.
3. Heat the flux with the torch untill it sizzles and insert into the fittings.
4. Apply the solder.

Spudshot alerted me to something else you can do while soldering. You can tin the inside of the fitting by applying solder to the outside of the pipe before you insert it, creating a stronger bond. Thanks, spudshot.

Links Newbies Should See
1http://localhost/forums/viewtopic.php?t=6164 A great sticky by Chewy. Contains lots of links that I would have posted if they werent in a different sticky.

A Basic Barrel Sealing Valve
This is similar to Clide's flash presentation, but in a 3d format. It is based off of the Indirect Linear Piston Exhaust Valve that plasticex uses on his LRPL-01.
<img src="http://x2.putfile.com/5/12611184945-thumb.jpg">
IN the photo, the horizontal blue structure is the chamber inlet. The vertical blue structure is the outlet to the barrel. The magenta object is the piston, which seals against the green elbow. The red cylinder is the piston cylinder, which gives it a smooth sliding surface. It's not that bad for my first 3d drawing.

Again, any additions to this list are greatly appreciated.
Edit: Thanks to spudmasterofmtwashington for making this a sticky.

by **ryanpowell167** » Sun Apr 03, 2005 2:35 pm

Well, all my pipe in my area is DWV but it is also perssure rated, and it has never failed in any of my combusitons or pnuematics. DWV is ok as long as it is pressure rated. And most DWV fitting are good for lower pressures.

by **plasticex009** » Sun Apr 03, 2005 3:27 pm

This is a good idea draculon. I updated/added to your list. I hope that we can get enough common terms compiled to make a sticky. So if people could suggest common terms to put into this list it would be helpful.

<h1>Piping Terminology</h1> Note: piping refers to both pipe and fittings.

PVC (Polyvinyl Chloride): Common high strength plastic material used in piping systems. The main drawback to this material is its tendency to fragment when it fails catastrophically. The risk of a launcher rupturing is very very low when used within the pressure rating of the pipe system. Most people use 100 psi as a maximum in pneumatic launchers to obtain an even higher safety factor.

ABS (Acrylonitrile-butadiene-styrene): Plastic piping material that is very tough in nature and will not fragment. Pipe not rated for pressure can be used for combustion launchers. Piping rated for pressure can be used for combustion or pneumatic launchers although it is hard to find.

Cell Core: Lightweight piping made for use in DWV systems. The pipe is composed of two thin layers of solid PVC plastic with a porous core sandwiched between. This material can be used in combustion launchers safely.

NSf-XXX: (NSF is the acronym for National Sanitation Foundation.)
<ol><li>DWV: Pipe/fittings meant to be used only for gravity flow (Drain, Waste, or Vent) systems. The fittings in this class usually have thinner walls, shorter sockets to bond to pipe, and, if a threaded component, fewer teeth that can be screwed into a joining fitting.

The weak joints caused by these components are why it is not recommended to construct pneumatic launchers out of DWV piping. Using this class of pipe for combustion launchers has proven to be safe. Avoid DWV clean out caps in all situations! They have proven to be the most failure prone component on many launchers.

<li>PW: Pipe/fittings meant to be used in potable pressurized water systems. Standard for use in combustion or pneumatic launchers. Some pipe/fittings will have both PW and DWV stamped on them signifying they can be used for both pressure or gravity flow systems.

<li><a href="http://www.nsf.org/business/newsroom/connection00-1/connection_page4.html">For more information on other NSF categories look here.</a>
</ol>

XXX p.s.i.: This denotes the pressure rating of the pipe system (including PVC fittings of the same class [e.g. NSF-PW]).

SCH XXX: Schedule (SCH) refers to the thickness of the pipes walls. Common schedule values for PVC piping are: 40, 80, and 120. The higher the SCH number, the thicker the pipe wall and thus the higher the pressure rating. <a href="http://www.harvel.com/pipepvc-sch40-80-dim.asp">SCH40-80</a> <a href="http://www.harvel.com/pipepvc-sch120-dim.asp">SCH120</a> dimensions/pressure ratings.

SDR XXX: Standard dimension ratio (SDR) is another way of classifying pipe wall thicknesses. In the SDR system, the ratio of wall thickness to pipe diameter is constant. This means that all piping in a SDR class has the same pressure rating. Common classes of SDR pipe are 13.5, 21, 26, and 41; lower numbers correspond to higher pressure pipe. <a href="http://www.harvel.com/pipepvc-sdr-dim.asp">Dimensions and pressure ratings for common SDR piping.</a>

CTS: Copper tube size (CTS) is the standard for copper piping sizes. CPVC is also available in these sizes. <a href="http://www.copper.org/applications/plumbing/techref/cth/handbook.pdf">The Copper Tube Handbook (7.0MB PDF)</a> contains a great deal of the information about copper piping and is a worthwhile piece of literature to have handy. <a href="http://www.harvel.com/piping-cts-dim.asp">CTS CPVC sizes and pressure ratings.</a>

<h1>Fitting Terminology:</h1>

Male NPT: Threaded fitting with male (outside) threads having a taper of .75" per 12" (~3.576Ã‚Â°).

Female NPT: Threaded fitting with female (inside) threads having a taper of .75" per 12" (~3.576Ã‚Â°). NPT stands for National Pipe Thread which is the standard pipe thread system of the United States.

Socket: Fitting containing female solvent weld joint(s). Examples of common socket fittings are tees, 45Ã‚Â° or 90Ã‚Â° elbows, end caps, and couplers. Sockets are usually tapered to ensure a leak free fit.

Spigot: Fitting containing male solvent weld joint(s). Examples of common spigot fittings are reducing bushings, street elbows, and plugs.

by **pacogoatboy** » Sun Apr 03, 2005 5:16 pm

I believe that pipe is supposed to list all of the standards it conforms to, so if a pipe says DWV, that only means that it can be used for DWV purposes. It does not necessarily mean that it is not pressure rated. If, however, it does not also say PW or XXX psi somewhere on the pipe, then it should be treated as though it were not rated at all. PW or DWV is usually used on fittings, and pressure ratings are printed on the pipe itself.

DO NOT believe the guy at the hardware store who claims that SCH 40 means that something is pressure rated!

Valuable information for copper tubing can be found in the link below. There is just too much info to sum it up...
http://www.copper.org/applications/plum ... _table.htm

**Sponsored**

by **Dextromethorphan** » Fri Apr 15, 2005 1:14 pm

I tried to make a list EXACTLY like this a while back and put it on a web page but everyone was like "you can't have one single all-inclusive web site. That's impossible" even though I just wanted to make a list. But hey, at least it finally caught on, so...uhh...great diea...even though I already thought of it, lol.

by **SMOMW** » Mon Apr 18, 2005 12:27 pm

I'm making this a sticky. It's a good thing for beginners to read.

by **RMS** » Thu Apr 21, 2005 2:16 pm

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by draculon
[br]Painting Pipe: This is how I do it.
1. Sand all the lettering off with 220 grit sandpaper.
2. Clean pipe with medium strength lacquer thinner to remove dirt and grime and leave a more proffessional outcome.
3. Krylon Fusion works best for plastic, but ohers work well.
4. Apply paint by spraying 6-12 inches away from pipe. Take your time and don't try to cover the whole thing in one go. This will help to eliminate drips and runs.
5. After your first coat has dried, from anywhere between 12 minutes to an hour, repaint it.
6. Let it cure for at least 24 hours(on Fusion it says 7 days).
Congrats, you painted it!!
<hr height="1" noshade id="quote"></blockquote id="quote">

Does this painting procedure work for ABS? PVC? both?

by **draculon** » Thu Apr 21, 2005 8:07 pm

I should think it works for both. I can't find ABS in my area so I'm assuming it works.

by **Icesoda** » Sat May 07, 2005 12:34 pm

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by RMS
[br]
Does this painting procedure work for ABS? PVC? both?
<hr height="1" noshade id="quote"></blockquote id="quote">

It's a general painting guide, works for PVC, ABS, Aluminium, Steel, Copper, Other plastics, My arm, Rocks... Uh. Well, okay. Works for almost everything[:p].

by **airpress** » Wed May 11, 2005 1:15 pm

I have a question.

How many pressure can hold standard PVC pipe?
For a pneumatic.