Newbie on plugs

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#1

Hi there have been reading over this great site over the last few days as i wanted to get clear in my head what to ask before talking crap.

I’m new to the whole process of fiberglass and carbon parts but was hoping that i would be able to get some guidance on methods so that i buy the correct products etc…

I’m based in the uk and have seen the list people have produced for suppliers so i will go through those to source what i need.

my plan is to make a carbon air box for my car making use of the limited space and have enough of a cold air feed to supply and also keeping as much hot air out. i was thinking a 2 part and then fixing both halves together once complete. the top part of the air box would have an access panel flush to the top, the filter i thought would mount to a turned aluminum piece bonded in between the 2 sections

i did think whether it would be worth using expanding foam to get the shapes of the cavities i can fit the airbox and feed in but then i would need to remove them and also turn these into plugs to take molds from

i then thought about shaping them from high density foam but am just not sure which is the best method as i would like to make it in the best way possible

any advice/opinions are welcomed to guide me

thanks in advance Stuart

#2

You can use a urethane foam of 5-10lb density. If it’s going to be machined, 15-40lb gives excellent results, and requires little finishing work, but is difficult to shape with hand tools. Too light and it crumbles easy and requires a lot of work to fill the pores.
Coat with duratec base coat, primer, and hi gloss. You’ll end up with a beautiful plug that after waxing is ready to make a mold(s) from.
Keep in mind where any parting lines are going to be, even single piece sections might have multi-piece molds.

#3

Hi thanks for the advice there, would you mainly recommend making a mould using 2 part polyurethane of the area it will go in and shape from there or make an oversize plug and trim to suit ?

i will be finishing it by hand so will do my best in making it.

if anyone else has any tips please post them or guide me to what i should look for.

thanks again

Stuart

#4

2part foam works great unless you can buy a block of the PUR foam and hand shave/ shape down.

The plug is the exact size of the finish part. And the mold will reproduce any scratch or imperfection too…do it right the first time and be done with it.

Is there a market for more than 1x of these? Just trying to get you thinking out of the box of “ME” only…LOL. Make your hobby pay for it’s self…until it becomes your business. :cool:

#5

well there could be a market but i’m not so sure yet as it’s not really a mass market car mazda 323 GT-R.

PUR Foam is polyurethane right? i have been looking for this kind of thing but not sure where to find it in the uk.

i will work as hard as i can to smooth and polish the plug to ensure the mould doesn’t get ruined.

thanks for your inputs !

#6

PUR is Polyurethane

I guess I need to have my own terms glossary listed on here…:smiley:

#7

it’s ok i think polyurethane is usually referred to as PU so it was easy enough to guess.

now i just need to find the right stuff

thanks again

#8

Yea, I guess I should refer to it as PU and PUR as Polyurethane Resin…I never stop learning…:smiley: