Pnuematic fittings
 

It appears that there aren't any standard push-to-connect pnuematic fittings in the kit (unless I'm missing something: http://www.usfirst.org/uploadedFiles...%20Rev%20E.pdf) so I'm wondering where does everyone get the little plastic push-to-connect fittings?

Re: Pnuematic fittings
 

Most industrial supply companies will source them, especially those dealing with pneumatics.

For low quantity we usually just use mcmaster and add them to our normal orders.

Re: Pnuematic fittings
 

Also check out SMC's website.

We've had the same few (large) bags of them for a little while now, so I couldn't say where we got them (maybe even in the 08 or 09 kit or something?). Odd that they give you all that brass and no quick-connects...

Re: Pnuematic fittings
 

Allied Electronics: http://www.alliedelec.com/pneumatics/fittings/

Re: Pnuematic fittings
 

The push-to-connect fittings were offered this year as one of the choices in the extended FIRST Choice KOP through AndyMark, so keep an eye out there next year too.

We order extras from a variety of places, usually chosen based on building a bigger order. Here's a T-connector for instance: http://www.alliedelec.com/Search/Pro...&MPN=KQ2T07-00
Other common fittings are listed at the bottom of that page too. P.S. Same as Chuck's link above.

Re: Pnuematic fittings
 

What ports do our pnuematics have? These (http://www.alliedelec.com/pneumatics/fittings/) all have NPT 1/4 or 1/8 threads, but the festo solenoid (http://www.andymark.com/product-p/am-0888.htm) has M7 threads. Will these be able to interface?

Re: Pnuematic fittings
 

Princess Auto carries quite a selection. www.princessauto.com. The cylinders they sell are metric but they carry both metric and imperial fittings.

Re: Pnuematic fittings
 

FIRST requires 1/8" NPT, but that's just the diameter of the airflow cylinder (technical term anyone?... NPT I guess :p ). The threads will vary. All of the brass fittings and quick connects teams usually get (including all the ones posted so far, I think) have the same standard thread (not sure exactly what it is). However, the newer Festo (and SMC I believe), while they have the same NPT, they have a different fitting that you have to buy from the mfgr (as far as I know), which uses the M7 you are seeing on their website. These interface with the rest of your interface then with the standard 1/8" NPT tubing between the two different types of fittings.

Re: Pnuematic fittings
 

Interface? They are different threads for the specific applications. The push in part of these fittings have nothing to do with the port size thread type.

The push in fitting needs to be for the standard FIRST .25" hose size. The fittings you get from AM will fit this hose and whatever fittings you will buy will need to be sized for this hose. I believe you will find this to be the standard size for most of the fittings you will see.

Also if you see 6mm hose size fittings they will works as well (I belie what comes from on the festos from AM is 6mm)

Re: Pnuematic fittings
 

I know of no FIRST requirement for fitting thread size only hose size.

NPT = National pipe thread

Re: Pnuematic fittings
 

Oh... that's news to me, thanks for the enlightenment :)

I knew it was just the hose size restriction, but not knowing the acronym I assumed that was it... You learn something new everyday!

Re: Pnuematic fittings
 

Would this be legal hose?

http://www.princessauto.com/power-tr...matic-hose-red

It's the right dimension, but 125 max PSI seems to be cutting it a bit tight.

Re: Pnuematic fittings
 

IndySam is correct except for
The hose size that IndySam is talking about is:
The OD of the Freelin-Wade tubing in the KOP is 0.25" and that is the push-to-fit size needed.

If you use push-to-fit fittings, I suggest getting a tubing cutter and ensuring that you cut the tubes square. Angle cuts cause so many leaks ... :rolleyes:


Also, these are last years rules ... next years may (or may not) be radically different. YMMV.

Re: Pnuematic fittings
 

As for the pressure, 125 psi should be just fine (correct me if I'm wrong). I'm pretty sure all the hosing we have is labeled with that as well. Our pneumatic systems never get above that on the high end (k maybe like 130), and I'm guessing that published number is before the safety factor of at least 2.

Re: Pnuematic fittings
 

I don't recall Princess Auto carrying the hose but a new colour hose comes in the KOP every year - the supplier was taking suggestions at the championships. You can buy approved hose from McMaster Carr. The big advantage of Princess Auto is that you have two in Calgary and they're a lot cheaper than McMaster Carr.

Incidentally, National Pipe Thread (NPT) is tapered at 3/4" per foot or 1:16 so that the threads lock to give a seal (assisted by Teflon tape or pipe dope). 1/8 NPT has 27 threads per inch. We had an issue this past season with some Festo solenoids that had been anodized after threading so that the push fittings wouldn't thread in. We had to re-cut the threads with a 1/8 NPT tap.

Re: Pnuematic fittings
 

Excellent point, that one tool will save you hours of leak fixing and should be in the toolbox of anyone using pneumatics.

Re: Pnuematic fittings
 

I endorse the comments about cutting the tubing properly. Impress upon everyone who works with pneumatics that this is critical.

As for the pneumatics rules...hopefully there will be some further improvements, but as they stood in 2011, the rules were very strict, but relatively straightforward. It's easier for you to just refer to the rules than for me to reiterate everything, but here are some highlights.

Tubing is restricted by inside diameter: only Ø0.160 in ID is allowed. Since the Princess Auto tubing doesn't seem to indicate the ID, you'd have to demonstrate to the inspector that the tubing was the right size. Ø0.250 in OD tubing is often found with this ID, but there are variations.

The vendor rates the tubing for 125 psi working pressure; that's sufficient, so bring a printout of that web page to inspection. (Allowing tubing documentation in lieu of factory-printed markings was a great change.)

As for the ¹/₈ in NPT restriction, it's a bit non-obvious. By supplying and allowing parts that don't use NPT fittings (e.g. the Festo valves), FIRST is endorsing the interpretation that it's based on size rather than the presence of NPT threads. This effectively means that the port diameter may not be larger than that of a ¹/₈ in NPT port, whatever the actual method of connection. Notably, that's different from the orifice diameter, which happens to be around Ø0.125 in on a lot of ¹/₈ in NPT hardware. In fact, the maximum port diameter that would engage a ¹/₈ in NPT fitting is about Ø0.37 in, but because the depth of the tapered port is unknown, the maximum diameter is not precisely defined. (This is therefore an area for improvement in the rules.)

Given <R67B>, I'd try to avoid this in the future. (That's arguably a prohibited modification to a pneumatic component. You're not supposed to perform machining operations on valves.)

Re: Pnuematic fittings
 

McMaster has push fittings.