[DjNik]

Guys when constructing a sub enclosure there are two options for it-Mdf or fiberglass.Which is a better option SQ wise?
I have always considered Mdf to be a better material.
The only advantage of fiberglass according to me would be the option of constructing it the desired shape.
Another thing that has troubled my mind is that how does one determine the volume of enclosures like the following-

[shreyasma]

Using marbles. We can create a cardboard box with the desired volume then fill it up with marbles. Then we can fill the FG enclosure and see if its same.

[Harrie]

Put some gel coat on the mdf rings and spacers first. Then pour water from a can. I use a 5L can and 1L can. 28L = 1Cu Ft.

[shreyasma]

See this

Starting Fiberglass sub box! - MP3Car.com

[DjNik]

Thanks for the link.

[phamilyman]

You need to exclude the volume occupied by the sub cone itself

[abhinav.gupta88]

I think a box which has flat sides would be better for the working of the sub.
Gurus would know better.

[navin]

fiberglass needs a form for the mould. One option is to make this form out of very thin MDF (say 6mm) and let the form adhere to the resin. hence you will get a composite box (6mm mdf + 3mm FRP).

you can use marbles or water but I prefer sand. I have access to dry sand (because on the machines I work with is a water jet) so it is easy. marbles or water will do just fine.

sand density is 1.6, water is 1. I assume marbles will be around 1.6-2.

[DerAlte]

Originally Posted by abhinav.gupta88

I think a box which has flat sides would be better for the working of the sub. ...

No, doesn't play any role. The rear wall should be at a decent distance from the back of the magnet not to constrict VC cooling.

Originally Posted by navin

... I have access to dry sand (because on the machines that I work with is a water jet). ...

A-ha!?!?

[navin]

Originally Posted by DerAlte

A-ha!?!?

DA it is something like this
Water Jet Cutter and Abrasive Waterjet Machine Manufacturer -- waterjet cutting machine and water jet cutting spare parts

the machine spits out a mix of sand (that must be clean and dry) and water.

The spill off is treated and the sand reused.

[DerAlte]

I know, Navin Was just joking about dry sand with water jet sounding like an oxymoron! If we try pumping the sand and water as a slurry, the pipes wouldn't last 5 minutes, so the slurry is made outside the nozzles. Nifty trick!

[navin]

For minute there the "confused" smiley lead me to believe that you actually were. :-)

[yashshroff]

Originally Posted by navin

fiberglass needs a form for the mould. One option is to make this form out of very thin MDF (say 6mm) and let the form adhere to the resin. hence you will get a composite box (6mm mdf + 3mm FRP).

you can use marbles or water but I prefer sand. I have access to dry sand (because on the machines I work with is a water jet) so it is easy. marbles or water will do just fine.

sand density is 1.6, water is 1. I assume marbles will be around 1.6-2.

I know this is a old post, but relates to what i want to know.
How do we combine MDF and FRP, i saw another one of your post's saying to use Marine grade plywood sandwiched between FRP, how do we make those, like AFAIK mdf will not be flexible enough. Please shed some light

[yashshroff]

Originally Posted by yashshroff

I know this is a old post, but relates to what i want to know.
How do we combine MDF and FRP, i saw another one of your post's saying to use Marine grade plywood sandwiched between FRP, how do we make those, like AFAIK mdf will not be flexible enough. Please shed some light

Sorry to be posting againn !!... does it mean to use MDF on front with driver cutout and fg for back mould ?