[Boone]

We have some Nakamua NTY3's that each have 3 high pressure pumps. They are very loud so I was wondering if anyone had any ideas on how to baffle them. I was thinking of building boxes out of either 1/4" ply or luan lined with 1-1/2" acoustic foam. Or maybe just putting up a sheet of the foam on the wall behind the pumps. Any thoughts?

[underthetire]

Cool jet and chip blaster cover the pumps with a box and acoustic foam. You may have to add a fan to keep air moving though.

[aarongough]

I would recommend using MDF for the enclosure rather than plywood. MDF has very good sound damping qualities... You may find that it significantly reduces the sound level just by itself without any lining, provided the enclosure is well sealed/baffled.

Plywood is generally made of quite hard wood and would serve to simply transmit the sound rather than damping it. Acoustic tiles would help, but they are *very* expensive and may not work as well as you expect.

I used 5/8" MDF to make an enclosure around my CNC router, once the enclosure is shut the whole thing is very quiet, easy to have a quiet conversation right next to it.

Personally if moisture is not an issue then I would go for 3/4" MDF lined with the same material that they use for floating ceilings in offices. Cheap, rugged and effective. If moisture is an issue, then you're probably going to have a hard time finding good materials that can resist the moisture. Rock wool might be a good place to start.

[Bob La Londe]

How much fluid are these pumps using? I have a Little Giant pump and I can barely hear it when I do a system test with everything else turned off. I have to look at the hose to make sure I see liquid moving towards the nozzles.

[underthetire]

I've seen the high pressure pumps on the nakamuras. They are probably the cat pumps pushing 1000psi at 5 gallons a minute or so. These are not little pumps if it's what he's talking about.

[Boone]

Yea, they are some pretty large pumps. We're going to try to isolate the casters from the floor 1st, which I don't think will do anything. Then we will build the boxes. I think MDF will be too heavy because we have to go in there frequently to clean out the filters, that's why I was thinking luan or 1/4" ply.

Thanks folks...

[Bob La Londe]

1/4 plywood will probably just act like a passive diaphram. It won't deaden much. MDF with doors or removable panels maybe?