Back Pack guns - What's out there, or build my own?

[isoaker]

I've tried the straws and such out and for now the answer is simply no. The straws work by reducing the internal diameter of certain areas which will allow the water to flow straighter. I personally do not believe the screens to much anything.

I have not seen any real differences with 4" straws added. Simply put, you shouldn't ever need to use those except as a last resort if your water gun can barely put out a stream. Because we know how we should construct a water gun now, we should not rely on cheap tricks that are not of the highest possible design standards.

The screens I mentioned mostly for holding the straws in place, otherwise I fear they straws would be shot out being a smaller diameter than the tubing.

As for laminating the flow, 'tis just theory for me and haven't had actual experience testing things with and without, but do recall Big Bee mentioning them in the past. If straws do little difference, then hopefully frankenbike's thought of using larger nozzle piping should still produce a good, solid stream, though thicker than the commonly used 1/4" stuff. I suppose it's also a balance between nozzle size, pressure supplied by the firing chamber, as well as nozzle smoothness to prevent deformations of the stream shape upon exiting the orifice. Not sure I'd consider the straws as 'cheap tricks', though, since for the typical consumer, most wouldn't know about the straws so no one would care whether or not they were present in a water blaster. The fact that they are there suggests that the manufacturer felt they were useful in some way for those soakers (though perhaps not so useful in some homemade designs).

Due to years of homemade water guns being taboo, barely any developments have been made, so you can (and should) pioneer the pressure-washer gun.

Dunno if I would have ever considered home made water guns as taboo. However, I still definitely believe those building them should have some good knowledge on what they're getting into and things to consider before going out and building things. I'd hate for someone with only partial knowledge to be building a homemade out of substandard or unreliable parts and having a pressurized section fail on them, potentially doing damage and/or injury.

[frankenbike]

Even when you know what you're doing, there's still the chance of some sort of design or material failure. Isn't there a show on the History or Discovery channel called "Extreme Engineering Failures" or something like that?

I suppose I should spend the extra money and get the larger size. I can always use a smaller nozzle on it. I'll look for a local source this week so I can actually see what one looks like and see if it's suitable or can be properly modified for my purposes.

[isoaker]

Even when you know what you're doing, there's still the chance of some sort of design or material failure. Isn't there a show on the History or Discovery channel called "Extreme Engineering Failures" or something like that?

Yup, but it's still better to have an idea of things that can go wrong and to take some precautions when doing something rather than think that you can do things that you can't (i.e. I wouldn't give someone car keys and tell 'em to go driving just 'cos they've seen others drive. Even trained drivers get into accidents, but untrained and overconfident ones get into more.)

As for nozzles, well, it all depends how things behave based on the system's power and rate of feed to the nozzle as well as any turbulence introduced from valves and hosing. I believe either Doom or another built a nozzle with interchangable nozzle diameters that could be attached. That sort of system would pretty much cover you in terms of flexible nozzle performance, IMO.

[frankenbike]

Well, I went ahead and ordered one of these:
http://www.pressurewashersdirect.com/catalog...._id=148

Expensive, but it gives me some wiggle room in performance. I've seen a picture of it in a PDF catalog (but a direct link is near impossible) and that grip looks like the grip on an assault rifle. I guess I'll find out what kind of attachment it has at the end. I'm hoping it's just a threaded end that I can just use a tap to thread a nozzle with. I have some aluminum I can put in my lathe to tool a tapered outlet.

If it's a bayonet kind of thing, it'll be more problematic but I can figure it out.

No doubt about it, I'll look like a terrorist with the rig I'm thinking of. I may get a coverall suit and dress up like a maintenance man. People tend to ignore anyone who looks like a maintenance man, even after everything they've seen in action movies where the terrorists always dress up like maintenance men