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Varying APHs

Posted: Sat Aug 13, 2011 2:07 am
by mr. dude
The discussion here had me thinking about how we can arrange the PCs on a standard APH.
I have some basic drawings to reduce the amount of writing I have to do.

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Using that as the standard APH shape, the problems outlined in the topic linked above are: 1) the sudden decrease from 3" to 3/4", and 2) turbulence. The following design was proposed:

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This gives room for more gradual reduction and has a more linear flow.

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This is something I drew up while thinking about the second design. I feel like it provides a more linear flow, though I can't back it up with physics (I love this excuse, "my brain is in holiday mode").

Of course, the seperate air/water design is the best, but for a standard APH, let's discuss. Do you have any ideas?

Re: Varying APHs

Posted: Sat Aug 13, 2011 11:44 am
by atvan
The second 2 have a lot of dead space. You do not have the bent PC designs there. The reson for these is not linear flow, but to inrease firing angle posiblities. Also for sake of completness you should have the n00b linear flow APH that won't work. I can see this thread being a reference, where n00bs can look at all the possiblities for PC arangement. Alernatively, your post could be added to the customization pages of the APH article. Don't forget to edit the original post when you make more drawings.

Re: Varying APHs

Posted: Sat Aug 13, 2011 2:05 pm
by wetmonkey442
I still don't understand the concern over the reduction in pipe size of the PC to the smaller size pipe for the nozzle. The decrease in size increases velocity which allows a buffer for the external laminator to slow down the stream once again to smooth out turbulence caused by the decrease. So, in the end, your left with a blaster that has the same exit velocity, same lamination, but NO dead space. It's kinda a no brainer, imo.

Re: Varying APHs

Posted: Sat Aug 13, 2011 2:14 pm
by atvan
I believe the point is to allow more flow through the bend in the pipe. Bends normally reduce flow, thus making the gun weaker. However, there are other ways to overcome this. One of the easiest ways is to use a smaller nozzle. Also, brass ball valves have a limit in flow. For example, my largest nozzle is the same size as the hole in the valve. Any larger, especially without a laminator, would just rip the stream apart, as the valve cannot keep up with the nozzle making a non-round stream.

Re: Varying APHs

Posted: Sat Aug 13, 2011 6:47 pm
by mr. dude
What atvan said. It's not so much about eliminating the reduction as it is repositioning it to a more favourable location. It helps provide a more linear flow, and the 3" elbow might have less dead space than the 3" tee design.

As for firing angles, it's a valid point, but 1) these are basic drawings that are only meant to show configurations, and 2) I've never been bothered by that limitation (I only ever use my soakers between 0 and 45 degrees anyway)

Re: Varying APHs

Posted: Sat Aug 13, 2011 7:01 pm
by atvan
You've never shot down a hill? :p also, later in the shot, your angles get reduced even more. The bent design helps with making more shot usable.

Re: Varying APHs

Posted: Sat Aug 13, 2011 7:14 pm
by mr. dude
Not really, no :p
Straight PC APHs can shoot downhill anyway, it's way uphill that they can't do.

Re: Varying APHs

Posted: Sat Aug 13, 2011 8:23 pm
by atvan
You said you olny shoot 0-45, thats why I asked.

Re: Varying APHs

Posted: Sat Aug 13, 2011 8:54 pm
by mr. dude
I just never find myself on a hill/always try to keep my distance, so pointing downwards never applies to me.