what kind of fleece?

whiterob wrote: bellsracer wrote: If you do need the cloth to stretch 2 ways, I use unbacked automotive carpet. It can stretch in multiple directions and is typically made of polyester so it will make a perfect chemical bond to most resins. I have not heard of doing that before. It seems like it would work okay except I wouldn't think it would work well for complex shapes. ~snip~

It holds up really well for complex shapes and designs. When you are under a time gun, it really breaks down the set and cure time. I've used nylon too but for time crunching, you can't beat UBCarpet. That's why it is used by so many top shops as the base for fast projects. From what I understand, it is also used a lot on those reality shows that makeover cars. They are in a time crunch so they need to break down the timing. pump My Ride is 10-14 days, Overhaulin' is 6-8 days, Trick It Out is 14 days including delivery times, etc. I am trying to remember a show that used to be on in Japan and Europe that did makeovers in 2-5 days. You get the idea. Something that they don't mention is that time crunching can also be spared if you know your mixes really well. (i'm not there yet, but I'm learning). A technique I saw where a mix is a bit colder that usual, but well mixed and then baked during cure time. Timing is crucial (like measured in seconds) and temperature too measuRED / set to individual degrees, but the result is a minimal warping, full strength setup. Unfortunately, the technique works ONLY if you know humidity, ambients, and mixes really well. I still need at least 2 more years of practice for this one.Never send your ducks to eagle school.

The difference between ordinary and extraordinary is that little extra.

The 3Ls of life: Learn from the Past, Live for the Present, Look to the Future.

ckeeler wrote: i dont use fleece, never have. im not exactly sure when people started using fleece anyway. i always use nylon. reinforce from the inside, not the outside. (cant figure out why people do that either, just makes for way more work than needed).

how do you reinforce tight corners from the inside of your box?? ive never used fleece i just go to my local fabric shop and look in the bargin bins for something that has equal unilateral strech and is about $2 per m.

as for using automotive carpet to speed up the drying process? if thats what you mean i dont see it helping much, and since the inital fabric is just for shape purposes eg it will never hold a substancial weight you can just dump a heap of catalysist into the resin sure it will cause it to crystalise and hence lose its structural properties but your not really after them so...

squires500 wrote: ckeeler wrote: i dont use fleece, never have. im not exactly sure when people started using fleece anyway. i always use nylon. reinforce from the inside, not the outside. (cant figure out why people do that either, just makes for way more work than needed). how do you reinforce tight corners from the inside of your box??

always, always, always, build your boxes so that they have no back side. then reinforce from the inside. and thats how you reinforce tight corners from the inside of your box.

here are just a few tips for anyone out there because i see alot of people doing things "strangely" when it comes to this stuff (IMHO).

1.) if possible, always use nylon or jersey material or grill cloth, something thin rather than thick like fleece or carpet. in the end you are going to have something much stronger this way. use something that does not have a bunch of "fuzzies" or "hairs" all over it. you just cause yourself more work with that type of material because you are a.) either going to have to sand all that crap off, or b.) cover the whole thing in body filler, and then sand all that junk anyway, which i think is a wiz poor way of doing things and makes way more work for you then needed to begin with. so......the choice of material is important and i recommend staying away from fleece.

2.) no matter what the project, if there is anyway possible at all, LEAVE ACCESS TO THE BACK SIDE. why? so you can reinforce from the inside. that means in the initial stages of making the MDF structural portion of your enclosure, or other project, plan ahead and build it in a manner so that there is no rear panel, that way you can reinforce the box on the INSIDE not the outside (as they say in the Guiness beer comercials, "BRILLIANT!!"). you can always add your rear panel later once you are all done reinforcing and if it happens to not be an enclosure, maybe you dont even need a rear panel. are we seeing the common idea here folks? by doing things a little different in the initial stages, you are creating WAY less work for yourself later on and you will end up with a nicer product.

3.) touching on number 1 again, once you are done reinforcing, and given the fact that you used something like the material mentioned, you should end up with something fairly nice to start before even doing any sanding. in other words (if you put enough resin on the material before you started the reinforcing stage) it should be shiney and smooth already. all you need do now is find the areas that actually need the shape modified a bit or blended in and sand thoses areas with 40-60 grit so that body filler will stick to it, and do your magic with it. once you get it where you want with what ever grit you prefer, go ahead and sand the rest of your project so as to remove any minor imperfections in the surface resin from the very first stage of putting resin on the jersey material as well. blend in your body filler. guess what? now your ready for a few coats of filler primer and some finish sanding...thats it.

you should end up with an outside surface that is mostly the original resin with only a few spots here and there that have body filler before you primer. you didnt have to "bondo" over the whole entire thing and then have to sand all that bondo. thats a crazy way of going about it. not only that, my customers want to have, and i want to give them, a "fiberglass enclosure" when they pay me to build them one, not a piece of "fleece covered in bondo". yuck! all that bondo = nothing more than a weak, most likely gonna crack, pile-o-crap. and look at all the sanding it took to make it too!! why that style or method is so popular is beyond me.

squires500 wrote: as for using automotive carpet to speed up the drying process? if thats what you mean i dont see it helping much, and since the inital fabric is just for shape purposes eg it will never hold a substancial weight you can just dump a heap of catalysist into the resin sure it will cause it to crystalise and hence lose its structural properties but your not really after them so...

What I meant is that I use the carpet because it provides a thick base. Also being made of polyester, it forms a chemical bond that makes it extra rigid. This means less reinforcement is needed and saving some time but still provide the flexibility and stretch needed to get a job done quick. I also like to embed metal mesh into the reinforcements to give it a frame for extra strength.Never send your ducks to eagle school.

The difference between ordinary and extraordinary is that little extra.

The 3Ls of life: Learn from the Past, Live for the Present, Look to the Future.

ckeeler you make some good points about finish on the front of the box which i believe is incredibly desirable the way Ive always built my boxes it to fiberglass the back side then build a frame off that then wrap material and glass the front but as you have rightly pointed out it makes a horrible mess of the front of the box the part you actually see i never considered having a whole in the back which could very easily be patched nicely from through the speaker whole. humm may ideas to ponder. im doing a some probono work for a friend on his 88 xj6 jag atm, new dash door cards roof and boot inc amp racks and sub boxes, ill try remember to take my camera along when i'm working on it and well see if i cant get some decent pics of it trying to glass inside. bellsracer im not sure how well you are reinforcing it by placing metal fibers into the fiberglass, indeed it will work but fiberglass is stronger then steel g per g and i can imagine easier to work with i personally would just spend the extra 15mins laying another coat of fiberglass. then again it depends on time/cost. in Aus most installers charge $500-1500 per sub box doing a mediocre job at best so materials at about $10/L fiberglass lets say $100 per box which is a fairly pricey build then $100 for paint, i get mine sent out as im pretty useless with a spray gun they have 300 left worst case for labor which i expect $60/h so 5 hours work which i don't see as a short amount of time it takes a couple of days for me to build a box but i could work on 10 at a time so really its only 4-5 hours of layout time. hence i only charge around $300 a box depending on finish. so back to my original point i dont see time being too much of an issue compared to quality. not that i doubt your work is quality but i dont like it when people get the wrong ideas. i had a mate who decided dry time was too much of an issue so started to triple the catalyst in his mixes. this has the massive side effect of crystallizing the fiberglass so in 2 years it will burst into brittle shards. id prefer for all those people paying for nice builds that people dont substitute quality is all.