My new CPS system (Almost Done!!!)

[Andrew]

This article explains how to solvent weld.

Whenever I pull it out of the housing, they aren't there anymore. They aren't in the pump housing. Oh and also I got the pump out of the housing.

You'll need to find those if they've gotten inside the blaster. I don't know how large your check valves are but you don't want the o-rings jamming them open (check inside the tee for them).

[Fishfan]

I found one of them (was on the floor), I'll look for the other one.

http://imageshack.us/photo/my-images/560/sdc11238g.jpg/
http://imageshack.us/photo/my-images/152/sdc11241.jpg/
http://imageshack.us/photo/my-images/40/sdc11241c.jpg/
http://imageshack.us/photo/my-images/29/sdc11244o.jpg/
Some detail on the pump. I took several layers of teflon and put it in the groove, and I took a lot of a electrical tape (that was yellow, because it was in better condition than the black tape.) It looks like it will seal a lot better. The pump rod was dry when I did this. I also sawed off the first groove, although it made the rod a tad shorter, it didn't really matter because the o-ring is in another groove. Since the pump housing came out, it is easier to work with and I will make sure that it seals really well before cementing it back on. When I get silicon lubricant later I will get the pump rod into the housing and test the seal.

This article explains how to solvent weld.

I didn't follow those instructions exactly, but I followed the instructions on PVC cement. I didn't do that mistake on the other parts, it just happened on the pump housing. Also, atvan said the water gun is pressure vessel. It will only be that after the second check valve, not the pump housing right?

UPDATE: I couldn't find the second o-ring, it must have fallen out, because the o-rings OD is smaller than 1/2 inch, so it would fall out easily.

[atvan]

When you are pumping there will be pressure equal to that in the PC- that is how the pump pressurizes the PC.

That pump looks nice.

[Fishfan]

Oh, okay. I see what you mean. Anyways, when I cement the pump housing on, I won't make the first mistake I made!

Oh and thanks for the comments on the pump.

[Andrew]

That pump looks nice.

It does too!

My only question now is, what is the third thick layer of electrical tape (further along the pump rod, furthest away from the o-ring) for? It will help straighten the pump's stroke (one of the purposes of the end-cap anyway) and stop the pump rod from being pulled too far out of it's housing (but surely the tape next to the o-ring will do that?). If you prefer to have it, and have good reason that's fine, but it will reduce you're pump stroke volume by a fair amount.

[Fishfan]

Well, the only reason for that is because I don't want to get the o-ring trapped in between the adapter and the pipe part of the pump housing, because it happened before and I don't want it to happen again. That is how the pump housing came out of the tee, from excessive handling trying to get the pump out. I guess I don't need it that far, I'll take a measurement and see how far it really needs it.
EDIT: I just did it, and I moved it about a 1/2 inch farther down.
One question, Will lubricant help keep the o-ring inside the groove, in other words, prevent it from slipping out of the groove? I would think it will, but I can't be sure of that.

[atvan]

It should. It did for me anyway. If you can get your hands on some silicon lube, you'll have plenty left over, and that stuff works wonders on the pump. My pump that would not move on my APH became very smooth, almost as good as a small stock gun and better than any that were of similar size.

[Andrew]

Well, the only reason for that is because I don't want to get the o-ring trapped in between the adapter and the pipe part of the pump housing, because it happened before and I don't want it to happen again.

OK, that's fair enough, I didn't realise how long the adaptor was. I assumed the single strip of tape beside the o-ring was enough. It's good to have a safety margin as well.

Will lubricant help keep the o-ring inside the groove, in other words, prevent it from slipping out of the groove? I would think it will, but I can't be sure of that.

Atvan is right, it should. The lubricant reduces friction between the o-ring and the inner surface of the pump housing. It's this friction which pulls the o-ring out of it's groove in the first place.

[Fishfan]

Okay, thanks. My dad is going to get some silicone grease at lowes later today Just to make sure its the right one here is the link for it:

http://www.lowes.com/ProductDisplay?par ... &cId=PDIO1

Just to make sure its the right lubricant.
Also, I just found our drill bits so now I can work on the nozzles. I'm going to do something similar to what you did on your water gun, Andrew, because I watched the horizontal blast on your water gun and I like it a lot. I'm also going to make a nozzle like the scatter blast, and also normal ones.

[atvan]

Mine came in a tube like toothpaste, but that looks like it should work.

[Fishfan]

What is a good nozzle size for maximum range? I just drilled a 3/32 nozzle, for a water-saving nozzle.

[Andrew]

So you looked through the SSCentral forums I see?

Frankly, I thought that video was broken (for some reason I can't open it with my .flv player???)
The fan blast spreads because of the washer, which seals the end-cap, intrudes into the nozzle holes at each side of the fan blast, which induces drag on the water, causing the edges to spread. If your end-caps are domed (rather than my flat ones) then you probably don't to do need this to achieve a spreading fan blast as long as you drill the holes perpendicular to the cap (follow it's curvature). I could only get flat end-caps so had to be a little creative to get the blast to spread.

If heard of others using aerosol lubricant, but the grease should work fine. You could place some in the gap between the two yellow tape sections, and that will lubricate the housing while you pump.

As for the best nozzle size for performance, that varies with each blaster. Mine works best with an 8.5mm nozzle, but I can't guarantee that will be optimum for your blaster. The best method is to test different nozzle sizes and graph the results (range against nozzle diameter). If you can get a hose connector with the same thread size as your threaded adaptor then that will be an efficient option for testing. The smoother transition of diameter usually offers better performance.

[Fishfan]

Okay, I got the lubricant, but Lowes didn't have the one I posted above. Is says DuPont teflon silcone lubricant. It says it lubricants and waterproofs.
Heres the link:
http://www.lowes.com/ProductDisplay?par ... &cId=PDIO1
Is that one safe to use? I thought I remembered seeing a DuPont article saying products marked with Teflon was a scam or something.

[Andrew]

Seems Legit.

[Fishfan]

Okay, but will it work for this application? Unfortunately, it doesn't have as one of its suggested applications as a pump for a homemade CPH

[atvan]

Is it like grease or is it runny?

[Fishfan]

It is runny, but it said it was for waterproofing.

[Andrew]

It also says that it's suitable for o-rings and sliding mechanisms. Sounds like it should do the job. It's supposed to be an alternative to silicone spray, so it should work just as well. If not you could always lubricate some drawers with it.

[Fishfan]

Okay. I will try it out and see what happens. Before cementing it I will test it to see if it hold up to water. Worst case is later on as the gun ages, if the lubricant washes away, I will just add more lubricant to it.

[Andrew]

Worst case is later on as the gun ages, if the lubricant washes away, I will just add more lubricant to it.

You will have to lubricate it now and then to get the best from it. Not too hard with the screw-on end-cap.

You might not have to take the pump all the way out either. Just adding more lubricant to that area between the two yellow tape collars should do for routine maintenance (it will get dragged along the inside of the pump housing as you pump).