This is a instructable about how to make your very own Fiberglass speaker shell.

My car is a 1994 520i BMW, Its my pride and joy :).

This project can be a bit pricey but it is cheaper then buyig custom made ones from a shop. this all up in materials was probably AUD $200, but i brought extras and more then i needed and for future projects. But look around and find the cheapest stuff if you can!

All steps are how i did  mine, you can change how you do them or follow mine, compeletly up to you.
I did a lot of research on how to do these but no one did a instructable on how to do speakers for the front of the car, only Subwoofers. I take no credit for coming up with this competely by my self, i looked and read a lot of instructables on how to do this.  I will update this instructable when i have painted mine as i am not at university for the moment where i can use a painting room with free paint :)

please comment, i will try to reply!!

And please ignore all Spelling Errors haha


* Fiberglass Mat ( 2 Metres )
* Resin & Hardener ( 2 / 3 Litres )
* Body filler ( 1kg )
* Wooden dowel ( Single lenght, 6mm )
* Speaker Spacers or MDF Cut to size
* Fabric ( Fleece or simular ) ( 1 Metre )
* 1" Brushes (least a dozen, cheap ones)
* Cups ( For mixing )
* Syringe ( For Resin Hardener )
* Masking Tape
* Painters Blue Tape
* Plastic ( Bin Bags or Protection plastic )

** All Materials are based Roughly on what i used **


* Dremel or other cutting device
* Hot Glue Gun
* Saw
* Sanding paper
* Ruler
* Fan ( Big )
* Safety Glasses or Goggles ( Safety First!! )
* Face Masks ( Suitable for Fiberglass Fumes AND / OR Fiberglass Fibers )
* Gloves ( 50 pack )
* Radio ( Help the time go by )

Time to get cracking!

Step 1: Preperation


This is very important as this will protect your car from stains that i have heard are very hard to get rid off.
If you follow this carefully you should have the same result as me. No Stainage.

Also Make sure the area your doing this in is well ventulated. I did mine in the carport with a fav next to the door airing the car while i did this.

Step one:

Pull off any Interior panels that are covering the speakers and the areas you want to fiberglass and the surrounding areas. atleast by a few inches.

Step 2:

Once Step one is done, Time for the taping to begin.

What you want to do is begin with the masking tape and cover the surrounding area and then put a few strips going into the the gap or speaker space to create the depth of the shell.

Im sorry i forgot to take pictures of this bit but i have the pictures of blue tape.

Step 3:

Same as step 2 but with the blue painters tape, this will hopefully prevent any resin slipping through to the carpet. Make sure to leave no gaps. Have a look at the picture.

Step 4:

Lay plastic down on floor or if there is no floor, then around the lowest part as gravity is a Heartless Bitch. Make sure to tape over the edges of the plastic so that the resin can not seep through under it. Make sure that any part that could get resin on it is covered.

Step 5:

Prepearing materials. Cut the fiberglass into either 3" squares or managable strips, entirely up to you. You probably want a sizable pile so you dont run out during the resin stage.


* You can draw a line with a marker on the tape of where you want the fiberglass final edge is to be, the ink should soak through to the fiberglass.

* Dont be shy with the tape. Seriously, if you care about your interior then cover the thing in tape.
Been thinking about doing this for a while with a sub in the trunk of a sedan.. I'm really thinking this will be the summer that I do it.. Nice 'ible.
thanks man, if your going to do Subs, make sure you do least 5 layers and probably coat the inside again with resin just to be safe. :) good luck

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