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Re: Really Compact APH

Posted: Mon Mar 07, 2011 8:59 am
by C-A_99
Read Ben's APH article to get his range estimates. http://www.sscentral.org/homemade/aph/

A 1" barrel isn't really necessary, as it would mostly benefit for higher pressures, higher than what is possible to pump to with a single-arm pump. (Unless you're Chuck Norris or something.)

Most of the time the blaster is aimed between 0 and 45 degrees. 90 degree PC's are most common because they have less awkward weight distributions, though a 45 degree PC gives a good handle if designed correctly.

Re: Really Compact APH

Posted: Mon Mar 07, 2011 11:06 pm
by strato_2r5
Well, Ben's APH has more PCs. I want to know how far mine will go. If it doesn't go past 30, I'm better off getting an Overload. Okay, I'll use a 1" pump because that's the one in the instructions, and 3" everything else. Do they have couplers for 3" to 1"? If not, how do I couple those and a 2L bottle to 1" PVC?

Re: Really Compact APH

Posted: Mon Mar 07, 2011 11:55 pm
by cantab
The two main ways to join different sizes of PVC pipe are reducing bushings and bell reducers. The former will probably be more compact.

I'd be very surprised if it doesn't make 30 feet. 50 should be a goal. Short range can be due to 'secondary' factors, most commonly a poor pump (that can't make enough pressure) or nozzle.

Re: Really Compact APH

Posted: Tue Mar 08, 2011 12:54 am
by C-A_99
The specifications there call for a 1/2" pump, not 1". Any pumps larger than 1/2" will be too difficult to pump to a decent pressure level.

Re: Really Compact APH

Posted: Tue Mar 08, 2011 1:20 am
by strato_2r5
Then I must have read it wrong. Okay, so I'll use reducing bushings for the pipes. Any ideas how to attach the 2L bottle? I think I saw something in soakernerd's thread.

LOWE'S HERE I COME!!!

Re: Really Compact APH

Posted: Tue Mar 08, 2011 1:28 am
by strato_2r5
Didn't the CPS Custom Assault Rifle have a ball valve with a trigger?

Re: Really Compact APH

Posted: Tue Mar 08, 2011 2:07 am
by C-A_99
Please edit instead of double posting to keep the forums clean, thanks.

Anyway, if you can find reducing bushings and couplers for 3" instead of merely bell reducers, use that as they are somewhat more durable. Otherwise, the bell reducers are the only option. (They're safe as long as they're assembled properly, and APH/CPH's never go anywhere near a level of pressure where it'd be dangerous.)

For triggers, the Riptide DR-4 is another design that uses one, with the casing design being more similar to stock blasters. Any kind of ball valve trigger is difficult to do however, and requires good pre-planning.

Re: Really Compact APH

Posted: Tue Mar 08, 2011 3:46 am
by strato_2r5
Okay, so I'll use a ball valve that opens really easily. I'll use JLspacemarine's design for a trigger (do I need to ask for permission?) because it's very self-explanatory and it uses a spring. Drenchenator uses rubber bands, and I don't really trust them.

UPDATE: I just noticed 3" is too big for my taste. I think I'll use 1 1/2" or 2". Is that a problem?

EDIT: Attached are my blueprints. Any problems?

Re: Really Compact APH

Posted: Tue Mar 08, 2011 7:16 pm
by C-A_99
Ball valve triggers also seem to require a lot of experimentation. I haven't done one myself, but I would conjecture that the design in your diagram would have some trouble opening completely. It will still work, but a fully open valve performs best.

1/2" valves open the most easily. You will of course, have to pick through the batches at the store and test to see which ones open the most easily, but generally, the smaller the valve, the more easily it will open. However, you will want a 3/4" valve if big riot blasts and what not are important, otherwise, 1/2" should suffice for most general uses. Using a 1/2" barrel/tubing to back up the valve is also usually a better idea as the valve will restrict flow anyway, and you'll save a little money with the smaller piping. (Not sure if a 1/2" valve backed with 3/4" improves performance over 1/2" backing by any significant amount.)

For both pressure chambers and the reservoir, simply do the math. Higher diameters bring up the volume substantially. If 3" is definitely too large, and you can't do much about it, then 2" will also work (with a slight loss in performance), but below that it's hard to tell how much performance would decrease.

As far as I know, no one in the community has ever required permission to borrow designs. The purpose of sharing designs is to help and bring insight to everyone else, as well as get feedback at the same time.

Here are some thoughts on the reservoir. A reservoir designed to be top heavy so the water flow will channel to an intake hole on the bottom (instead of using an intake tube) will use up all the water efficiently, whereas using a tube will leave a few droplets behind. However, such a reservoir is not very ergonomic and is difficult to build in. Since you are already using an intake tube, another possible idea is to mount the reservoir beneath the pump, which should balance things much better but does make it more difficult to pump. It's up to you.

Re: Really Compact APH

Posted: Tue Mar 08, 2011 11:29 pm
by strato_2r5
I just figured out that if check valves are too long, I'm going to have to use more curves than I want. Attached is my backup plan. Will it cause any problems?

UPDATE: I just visited my local Lowe's. They have all the parts I need, though I didn't buy anything yet. I'm just worried a little about a 2" pipe. They don't have PVC, it's ABS. Will it work with a PVC bushing? Also, what do they mean by CPVC in the pump construction page?

Any ideas for nozzle sizes?

Re: Really Compact APH

Posted: Wed Mar 09, 2011 4:41 am
by C-A_99
The check valves will be longer than that. They are always longer than they are thick. Check the homemade articles for examples of it.

The CPVC (a pipe used to carry both hot and cold water, and works by different measurements than Schedule 40 PVC) used in the pump construction page is for creating spacers to keep the O-rings in place. However, I'm not sure if I can recommend that. If you can't get a perfectly straight/square pipe cut on the CPVC, it won't turn out very good. Instead, I'd actually suggest trying epoxy putty to create the pump spacers. Also, from my experience, wooden dowels (rods) are TERRIBLE to use for pumps. Aluminum or plastic (the former being probably easier to find) does the best job for that.

Re: Really Compact APH

Posted: Wed Mar 09, 2011 5:18 am
by cantab
To join ABS to PVC, you will need a glue for the purpose - normal PVC glue won't do it. Apparently ABS-PVC joins are often prohibited in domestic plumbing, but products are nonetheless available.

Re: Really Compact APH

Posted: Wed Mar 09, 2011 5:09 pm
by soakernerd
Make sure the ABS is SOLID CORE. Their are foam core variants which should NEVER be put under pressure.

Re: Really Compact APH

Posted: Wed Mar 09, 2011 6:50 pm
by martianshark
If it has a foam core, it will say "celeur core" on it.

Re: Really Compact APH

Posted: Wed Mar 09, 2011 11:33 pm
by strato_2r5
Okay, so I'll just hope they have 2" PVC next time.

Off Topic: I'm trying to get a Max Infusion Overload (don't ask why). Is this website trustworthy? I'm uneasy about the picture; the reservoir is yellow. http://water-toys.biz/WebStore/ProductD ... ductID=288