15 replies to this topic

[nerfpower97]

Ok, I'm a pretty experienced modder, but I have no clue about tubing. My local lowes supplies me with 1/2 cpvc and it is just way to tight for my FBR and stock darts, so I've been looking for a new barrel type and PETG seems to be pretty popular.
Questions:
1) Does PETG fit into cpvc or pvc couplers and other attachments?
2) What does thick walled and other thickness terms mean?
3) How is the fit of PETG on stock darts (which is basically the size of my FBR)?
4) What size PETG is best? For stock darts? Tightest, loosest, etc.
5) How can I achieve PETG and what is the average pricing?
6) How durable is PETG?
7) Will hot glue work effectively on PETG?
8) In what ways is PETG different than cpvc? (Besides that it is clear and a different material)
9) Can you get a tube that has the same outer diameter as another tube but has a different inner diameter?
10) Is there a way I can get looser cpvc to where I don't have to bother with PETG?
Thank you to anyone who takes the time to answer these.
Sorry to any admins if I'm doing something wrong, I've never posted before.

[snakerbot]

1. No, but you can wrap it in tape and nest it in 1/2" pvc.
2. Nothing anymore. Everything easily available now is the same, which I believe is the same as the old thick walled.
3. Really loose. Darts fall out of it, at least with mine.
4. Doesn't matter anymore. See #2.
5. 2044T43
6. It'll withstand normal use, especially if you nest it in pvc, but still be careful with it. Don't step on it or anything.
7. Hot glue will stick to it if that's what you mean. It might also melt the petg if it gets hot enough, so watch it. The nozzle of you glue gun will also melt the petg.
8. Different size, different surface finish, (petg is smoother), more consistent dimensions. (CPVC is only regulated on the OD, so the ID can vary a bit.)
9. Depends on what you are looking for, what sizes you want, what material you are planning on using, and how much you want to pay. You may be able to try 89965K17, which will fit in cpvc couplers.
10. Since CPVC can vary on the ID a bit, sometimes different pieces will be looser than others. Bring some darts to the hardware store and check a few pieces.

[quertyman]

I have found that clear 5/8" OD 1/2 ID pipe is a looser fit than standard cpvc. you can find this pipe with this number on 9245k25. (sorry don't know how to hyperlink well) Any pipe with a 5/8 od will fit cpvc couplers. Also you could use sch 80 1/2 pvc, which has almost the same ID as petg and fits in pvc couplers.

Edited by quertyman, 20 January 2013 - 03:35 PM.

[snakerbot]

(sorry don't know how to hyperlink well)

Use the mcmaster code:

[mcm]part number[/mcm]

[Ryan201821]

9. Depends on what you are looking for, what sizes you want, what material you are planning on using, and how much you want to pay. You may be able to try 89965K17, which will fit in cpvc couplers.
10. Since CPVC can vary on the ID a bit, sometimes different pieces will be looser than others. Bring some darts to the hardware store and check a few pieces.

9+10) I've seen a wide range in sizes of CPVC, but nothing more than .500". If you're looking for a larger size than that, the next best options are 1/2" Polyester (9245K25), which quertyman linked to, or the much more expensive 17/32" brass (8859K34), which does not fit in CPVC couplers, or really anything useful. Both are pretty close to true 1/2", where CPVC usually is around .470"-.480" in my experiences. Next size up would be some 1/2" Sch. 80 PVC (48855K21). I emphasize the word some because I've seen other pieces of Sch. 80 that were .560"+ at hardware stores locally. McMaster Sch 80 is usually ±.05" within their listed ID of .526". There is also 1/2" Aluminum (1658T49) which is about the same size. I have never seen the stuff snakerbot linked to (89965K17), but it's much more expensive, and literally the same dimensions as the other aluminum. PETG is a little bit larger (.53") than both McMaster Sch. 80 PVC and 1/2" Aluminum, but it's difficult to measure the exact ID on a tube with such thin walls. The reason PETG is often referred to as "thickwall" is because that's what VisiPak calls it, who is almost definitely the manufacturer for this specific material. Various people sold this stuff out individually over a bunch of years before someone (I don't remember who), discovered they sold the tubing on McMaster. "Medium-wall" also to be sold by members of the community which is the same OD as thickwall, but around .550" ID. This stuff really isn't even used anymore and no one really readily supplies it other than buying a fuckton from VisiPak.

Really, best thing to do is get a bunch of barrel materials and see what your foam fits. If you're looking for stuff to fit stock darts, the brass or polyester should fit pretty well, or the Sch 80 if you want a looser fit. All of this information can also be basically summed up in this thread, which is literally just above this one.

[Draconis]

1. No, but you can wrap it in tape and nest it in 1/2" pvc.

However, Lee's clear, rigid PVC tubing is available in 9/16" OD, with a 0.50-0.51" ID, and also 5/8" OD with 9/16" ID. Nesting a little 5/8" over the 9/16" makes for nice light barrels that will couple in to 1/2" CPVC couplers.

7. Hot glue will stick to it if that's what you mean. It might also melt the petg if it gets hot enough, so watch it. The nozzle of you glue gun will also melt the petg.

I would strongly suggest against using high temperature hot glue. It will definitely warp and damage PETG, making it brittle when cooled. I've traced my early rocket sleeve failures to this phenomenon. PETG does adhere well with cyanoacrylate super glue, partially because the PETG is hygroscopic (Meaning that it absorbs water, though to a small degree in this case. This is also why you can wash out a pop bottle and refill it with water, but the water will begin to take on hints of the pop flavor.), while CA cures with exposure to water. So the CA will actually pull the moisture out of the plastic and bond with it in the process. This is the same reason that CA will bond your fingers together nearly instantly.

[The Snake]

What foam do You use. If its not the brown stuff or black stuff, then I would suggest going to Home Depot. There cpvc is much better then lowes. Believe me, Ive used lowes before. Home depots is a little bit bigger OD, but a good springer fit. Ive used it for air guns with lots of win too.

[snakerbot]

I have never seen the stuff snakerbot linked to (89965K17), but it's much more expensive, and literally the same dimensions as the other aluminum.

Whoops. Yeah, I was looking for your stuff, and found this.

I emphasize the word some because I've seen other pieces of Sch. 80 that were .560"+ at hardware stores locally.

This. Check before you buy.

[pop tart]

If possible, use brass. 17/32 has a nice fit on stock darts. Also, Ryan, I liked your
old avatar better.

[Draconis]

If possible, use brass. 17/32 has a nice fit on stock darts. Also, Ryan, I liked your
old avatar better.

Brass is substantially more expensive than almost every other material we commonly use, and is nearly always limited to 12" long sections. I felt very fortunate to find a supplier locally that was willing to sell it at $3.50 per foot, for a current project. Not at all what I would want to use on anything with a turret, that is for sure. Also, brass has the distinct disadvantage that it WILL tarnish, while plastics will not.

[mr trouble]

You can stretch your FBR to fit the CPVC better. Sometime if I need a in between size I'll take 5/8” FBR and stretch it across the room with a bungee cord and and a length of the barrel I want it to fit. Then I will run along the length of the FBR with a hair dryer and slide the barrel along the FBR checking the fit as I go. You can do it with 1/2” FBR if you need something a touch smaller. Also you can toss your FBR blanks in the drier and check them periodically for fit as they will shrink a good deal.

[spencerak]

Also you can toss your FBR blanks in the drier and check them periodically for fit as they will shrink a good deal.

I can attest for this shrinkage, I put some darts in my drier and forgot about them for about half an hour and the result was a single chunk of foam made up of small pill sized parts that had formerly been my 1.5"x.5" blanks.

[pop tart]

Brass is substantially more expensive than almost every other material we commonly use, and is nearly always limited to 12" long sections. I felt very fortunate to find a supplier locally that was willing to sell it at $3.50 per foot, for a current project. Not at all what I would want to use on anything with a turret, that is for sure. Also, brass has the distinct disadvantage that it WILL tarnish, while plastics will not.

I said if possible. The best barrel you're gonna get will involve
brass and petg- a telescoping barrel. Sorry Draconis if I came across wrong.

[JPRoth1980]

I said if possible. The best barrel you're gonna get will involve
brass and petg- a telescoping barrel. Sorry Draconis if I came across wrong.

For the record, I haven't seen any improvement at all with a number of telescoping barrels (nor have I seen improvement with using PETG instead of CPVC for air guns). Not entirely certain why this is, but in all cases, straight CPVC has proven to provide the most effective barrels. For me. In my own experience.

[Draconis]

For the record, I haven't seen any improvement at all with a number of telescoping barrels (nor have I seen improvement with using PETG instead of CPVC for air guns). Not entirely certain why this is, but in all cases, straight CPVC has proven to provide the most effective barrels. For me. In my own experience.

That is certainly possible. It all has to do with dart fit. In my case, I stretch all of my foam to fit CPVC, use it for springers, and use the Lee's tubing for air guns. Not a LOT loose, but just enough to reduce friction. Because of the sudden release nature of air guns, you don't really need an ideal-type barrel. That's mostly just for springers. It is nice that tightening rings or brass will hold the dart in the barrel, though.

[pop tart]

That is certainly possible. It all has to do with dart fit. In my case, I stretch all of my foam to fit CPVC, use it for springers, and use the Lee's tubing for air guns. Not a LOT loose, but just enough to reduce friction. Because of the sudden release nature of air guns, you don't really need an ideal-type barrel. That's mostly just for springers. It is nice that tightening rings or brass will hold the dart in the barrel, though.

Draconis is right. I hate my foam(frost king) but I do have nice barrels. If only all foam were the same.