Painting question, color coat is too soft to sand |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
Painting question, color coat is too soft to sand |
Gudhjem |
Apr 4 2010, 12:21 AM
Post
#1
|
Member Group: Members Posts: 133 Joined: 29-March 07 From: Castro Valley, CA Member No.: 7,629 Region Association: Northern California |
I've begun painting my car, panel-by-panel, starting with the trunk lid.
I'm using Interlux Bridghtsides paint. Yes, I'm rolling it on, mostly because I don't have a large compressor and because I am hoping to avoid all the mess of spraying in my garage. I spent a few days patching holes (luggage rack once upon a time I think), and spent a few days putting on a few coats of primer. Sanding the primer was no problem, and I've now started with the color. Problem is, when I try to sand the paint, it sticks to the paper. There's no dust created, the paper just gets clogged right away. It's as if the paint's not dry. The can says leave it at least 16 hours, I've left it 28, and it's not cold in California. Anyone know what's going on? (IMG:style_emoticons/default/confused24.gif) --Steve Here's before primer After Primer Sanding Block after trying to color sand |
rick 918-S |
Apr 4 2010, 07:31 AM
Post
#2
|
Hey nice rack! -Celette Group: Members Posts: 20,473 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region |
Boat paint is formulated with an elastic property that exceeds automotive paint. This is because water and conditions of water wear on it like crazy. Salt water, junk in the water, and hot cold reactions from the sun with instant cooling from water splashing on the hot paint cause expansion and contraction. Paint cracking and delamination are improved with a flexible finish with good crosslinking from the poly. You CAN wet sand and buff it. But it takes alot more time and effort. The finish stays rubbery and will gum up the paper like old acrylic enamel without hardner. The process requires a ton of patience and lots and lots of sand paper.
BTW: You will notice the finish will chalk and require buffing every year. I'm not sure but some marine paints have anti-fouling properties and shed by chalking. Helps keep junk from collecting on it. Some boat guy will know more than me about that and may call B.S. If I were you I would leave that paint at the shipyard and get some automotive top coat with a hardner. Even the lowest cost finish will give you a better end result. |
jd74914 |
Apr 4 2010, 08:23 AM
Post
#3
|
Its alive Group: Members Posts: 4,780 Joined: 16-February 04 From: CT Member No.: 1,659 Region Association: North East States |
BTW: You will notice the finish will chalk and require buffing every year. I'm not sure but some marine paints have anti-fouling properties and shed by chalking. Helps keep junk from collecting on it. Some boat guy will know more than me about that and may call B.S. If I were you I would leave that paint at the shipyard and get some automotive top coat with a hardner. Even the lowest cost finish will give you a better end result. Yep, many boat paints are ablative meaning they wear to keep barnacles and other nasty things from sticking. I know most ablative paint is super expensive (actually, its about as much as good catalyzed automotive paint) so this probably isn't a true ablative. I too would personally go with an automotive paint, even if that means getting some Rustoleam and rolling it on like some guys on a Mopar forum did. It should provide a much better finish. |
Lo-Fi Version | Time is now: 1st June 2024 - 02:40 PM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |