Bondo issues
Printed From: the12volt.com
Forum Name: Fiberglass, Fabrication, and Interiors
Forum Discription: Fiberglass Kick Panels, Subwoofer Enclosures, Plexiglas, Fabrics, Materials, Finishes, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=78369
Printed Date: May 10, 2024 at 9:56 AM
Topic: Bondo issues
Posted By: ottomatic481
Subject: Bondo issues
Date Posted: May 27, 2006 at 9:52 PM
ok so i made the box for my fourt 12 inch subs, and i covered it in fleece.. then i covered that in resin, then i covered all the wholefront with bondo, so i could sand it down for painting.. i have two questions, 1 is there are alot of little holes and tiny craters.. is there any way to get rid of all these easily or quickly, because ive been sanding for 3 days straight and its still not perfect.. and the last thing is, after i have the bondo all sanded down(im sanding it up to 2000) is it ready for paint or is there any thing else i need to do?? I plan on putting my truck in a car show and i realllly could use sum expert advice, thanks!!!
-------------
4 12's in a single cab f-150... yeah its nasty
Replies:
Posted By: gavin9797
Date Posted: May 28, 2006 at 12:42 AM
Well I have a couple ideas that may help. First one that comes to mind is a flowable polyester putty. apply a thin coat with the edge of your spreader, this sands much easier than bondo (ie 120g). It will fill your pinholes an small craters. Second Idea, I have read on here a common way is to mix a runny batch of bondo with resin and apply that with a brush or spreader. (maybe someone can find you a good ratio. I have heard 2:1, 5:1) Third Idea, assuming you are priming your enclosure, not knowing the kind of primer you are using I will go with what I am familiar with. A 2 part or 2K primer if applied in 3-4 medium wet coats will also fill these imperfections. If you see what looks like a little black hole just dab it with your finger tip while the primer is wet and it will fill the hole with primer. Try and do that in the 3rd or 4th coat, that way you will be able to sand out your finger print mark with no adverse effect on the finished paint job. Now I am going out on a limb here, some may disagree with me here... You do not have to sand your bondo down to 2000g (of course this is if you are priming it..) If you are priming the enclosure 280-400 is the finest you want to go to get proper adhesion between primer and bondo. After you have primed than you may wet sand with 2000g before paint. (even 1200 - 1500 is sufficient) The important thing is a mechanical etch for the Primer/paint to grab onto. To fine and you will have runs and flaking paint. To course (say 600 or less) depending on color the sand scratches will show up in your paint. Sorry for rambling...but I hope I helped
Posted By: mouglie
Date Posted: May 28, 2006 at 12:59 AM
hey that advice helped me, lol...
-------------
I shall never outrun my guardian angel - again.
Posted By: grantd
Date Posted: May 28, 2006 at 1:51 AM
I'm curious did you put mat/cloth on top of that resined fleece or did you just go straight to the bondo. If you didn't put any actuall fiberglass in there you might as well quit now, if your 4 subs are of any decent quality fleece and bondo aren't going to hold them.
Posted By: ottomatic481
Date Posted: May 28, 2006 at 9:31 PM
under the fleece is mdf, so is that still fine?? because just rapped the wood in fleece.. resined it, then covered that in bondo ------------- 4 12's in a single cab f-150... yeah its nasty
Posted By: gavin9797
Date Posted: May 28, 2006 at 10:22 PM
Is your whole box MDF? did you just wrap it in fleece and bondo so you could paint it? If you primed the box with high solids primer without the fleece and bondo you can still paint it to your desired finished. (you don't have to use fiberglass on a standard box). Though you could FG the flat board. (may be unecessary work) If you were making contours etc. to flush mount your subs with the fleece than you have to cover it with the cloth or mat. The fleece and bondo are just going to shatter on you. From here I do not know if you can take all the bondo off and still mat the fleece or not. you may just have to start fresh. Do you have any pics of the box to better show what you are doing?
Posted By: Velocity Motors
Date Posted: May 28, 2006 at 10:45 PM
Use a polyester primer to fill in the pin holes ( this is sprayable or paintable with a brush ) and will sand like chalk afterwards. As for the saniding to 2000 grit, we only sand our projects down to about 1000-1200 MAX as this allows for proper adhesion for the primer. We normally cut and polish the final coat as well to reduce the orange peel effect.
-------------
Jeff
Velocity Custom Home Theater
Mobile Audio/Video Specialist
Morden, Manitoba CANADA
Posted By: ottomatic481
Date Posted: May 29, 2006 at 10:21 AM
yeah i used mdf for most of it, and i used like 8 layers of fiberglass for the corners, the whole thing is rock hard, i just rapped it in fleece, to give a smooth look, so i could bondo it and paint it, thats all, the fleece and bondo have nothing to do with how solid the structure is
-------------
4 12's in a single cab f-150... yeah its nasty
|