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View Full Version : Ported fiberglass box.....



Zacmc212
05-14-2005, 01:38 AM
I have been searching through and reading lots of helpful posts on ported fiberglass enclosures. Most people say that you should make the box first, aim alittle high on the internal volume and figure out port length from there. But once it is built and you figure out the internal volume how do you add the port? Im sorry if this didnt make much sense its kinda hard to explain....and im new to glassing. Thanks.

Zacmc212
05-14-2005, 04:01 PM
anyone?

GCAdidas13
05-14-2005, 04:30 PM
It's all guesswork until it's actually built. Guess how many cubic feet you are going to have NET when you finish glassing, then make the port about 10 inches longer than what you think it should be.

Then, when you build the box, tape off the port from the inside and fill it with packaging peanuts. Then you can find the actual volume of your box.

After you have the actual volume of your box, you can find out what you're tuned to, and if you are tuned too low you can always raise the tuning by reaching into your subwoofer hole(s) and cutting excess port off with a jigsaw or something.

That's just what I would do, though.

CntInjaDisNinja
05-14-2005, 05:53 PM
make the box first

measure the internal volume with with packing penuts or water. When you find that buy a 3" or 4" hole cutter for your drill and then add the proper port length with PVC pipe.

ruckus
05-14-2005, 06:34 PM
make the box first

measure the internal volume with with packing penuts or water. When you find that buy a 3" or 4" hole cutter for your drill and then add the proper port length with PVC pipe. yup. Thats what im doing and I'll be using flange ends and fibering them smoothed out into the body of the box.

Zacmc212
05-14-2005, 09:38 PM
It's all guesswork until it's actually built. Guess how many cubic feet you are going to have NET when you finish glassing, then make the port about 10 inches longer than what you think it should be.

Then, when you build the box, tape off the port from the inside and fill it with packaging peanuts. Then you can find the actual volume of your box.

After you have the actual volume of your box, you can find out what you're tuned to, and if you are tuned too low you can always raise the tuning by reaching into your subwoofer hole(s) and cutting excess port off with a jigsaw or something.

That's just what I would do, though.

This is what i am going to try to do. But if i did use the pvc pipes how would u connect it to the box? glue? or just use some more glass?

Also i was looking on ebay and i think im going to use matte but im not sure how thick it should be?

Thanks for the help

ruckus
05-15-2005, 12:07 AM
Im using 3/4 oz mat for my box. I figure 3-4 layers will have it nice and strong

LightningStryk7
05-15-2005, 12:16 AM
but the port adds displacent, it is not a dimmensionless object, therefor ur box volume will decrease causing a diferent port tuning. But you could put a rather long tube in it, and then figure out the displacement and then see what it is tuned to, if its ti low cut a little off and figure again. And to seal the tube to the box perhaps Silicon would work :confused: