Summary for painting recycled plastic posts Discussion
recycled plastic posts are hard to paint, and the thread’s advice is cautious. The original questioner had a railing with recycled-plastic posts that had been painted years earlier, but the coating eventually cracked and flaked off, exposing the gray surface. They were looking for a durable, lasting solution and had considered sanding plus latex primer and latex paint. In the related answer, Yasemin Dunn listed several conflicting suggestions they had heard, including Tremclad, latex, alkyd enamel, and specialty plastic paint. Ted Mooney, P.E. responded that recycled plastics are usually a mix of materials, and that a truly reliable bond is unlikely because polyethylene in particular is notoriously difficult to paint or glue. He said ordinary outdoor latex is the best practical choice, noting it may not adhere perfectly but should hold together better than more brittle coatings because it can stick to itself as it shrinks. He advised cleaning the posts first and warned that peeling remains a possibility.
Q. Hi, years ago I built sort of a railing supported by 3 posts made of recycled plastic on the edge of my private vineyard. I don’t remember what I painted the posts with, but it looked okay for some years. It then eventually crackled and now is coming off in flakes revealing the grey ugly underneath.
My impression from previous research is that a combination of sanding, latex primer and latex paint might be the best option. I’m approaching the 70s, so I’m only interested in lasting solutions
Nesher Machert
hobbyist – Kiel Germany
May 25, 2024
A. Hi Nesher,
I think I’d focus on making the job as quick and easy as possible rather than trying to make it last forever because it won’t 🙂
So, for me, no sanding or multiple coats of primer followed by multiple coats of finish paint :-(
What I would do is get a good sized tampico scrub brush
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and scrub it once (to both clean it and remove any loose paint), rinse it, and spray it with one, maybe two, coats of made-for-plastic paint like Krylon Fusion for Plastic which uses plastic solvents for a good bond.
Of course times are changing, and in some areas consumers may not be able to get hold of such paints anymore; no country for old men 🙂
Luck & Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com – Pine Beach, New Jersey
Need quick confidential answers? $25
Need project assistance? $100/hr.
⇩ Similar, related, Q&As — oldest first ⇩
Q. Hi, has anyone painted posts made of recycled plastics? This is the plastics that would normally be recycled: milk jugs, plastic bags, etc. This is a new product on the market, which I am trying because I am tired of replacing fence post approx. every 10 years due to rot. I have tried cedar, creosoted stakes and posts and pressure treated posts.
I have been given various and conflicting information on how to paint them. example:
1) tremclad paint because it will stick to anything.
2) use latex paint because it will breathe, therefor not crack in the winter
3) use generic alkyd enamel because that is what the spray can plastic paints are.
4) use the plastic paint, but this would be cost prohibitive, because I can only get them in the small spray cans, and I need to paint two hundred 5″x5″x4′ posts.
5) do not paint the posts because they will peel and look ugly
The posts are a grey-ish colour and I would like to paint them white, to match my rails — purely aesthetic reasons.
Any information would be appreciated, because I’m at a stand still in my fencing, until I get this painting issue resolved. thanks
Yasemin Dunn
backroad farm breeder of children’s riding ponies – Hazelbrook, Prince Edward Island, Canada
2005
A. Wotcher Yasemin !
Recycled plastics? Hmmm. They would be a mixture of Pe, PP, ABS, styrene …. and to get a good bond, no, I don’t think that you’d ever succeed (it can be done but at a hellish expense). There is no (successful) glue, cement or paint for Polyethylene.
I’d use an ordinary outdoor latex. The paint may not necessarily
‘stick’ too well but it will STICK TO ITSELF and hence should be OK unlike on a flat surface.
Also, all paints shrink somewhat … with the expensive lacquer type paints shrinking considerably.
But peeling? Dunno. Give it a try with latex but clean the posts first of all.
Freeman Newton [deceased]
R.I.P. old friend (It is our sad duty to
advise that Freeman passed away 4/21/12)
A. If you are trying to paint polypropylene, you’ll find that most paints out there won’t stick too well. You could still get some cans of cheap white spray paint at the hardware store and do the job, but you’ll probably be painting multiple times in a year.
Jake Koch
G. J. Nikolas &Co.,Inc.
Bellwood, Illinois
A. To add my two cents to what has already been said, I would use a latex primer applied in two thin coats after first lightly sanding the plastic surface. Then I would apply the final finish with an exterior latex, again in two thin coats. I think that the primer over the sanded plastic will give you mechanical bonding to form a base for the painted final finish.
Gene Packman
process supplier – Great Neck, New York
Q. I don’t have an answer yet for you, but am very interested in where you purchased the posts. We are a sign shop looking for ways to lessen our impact. If we purchase some of the posts, we will also want to paint them and I will send you the results of our testing. At the moment, when we want to paint PVC plastic we use Sherwin Williams Alkalyd DTM (Direct-to Metal) paint.
Kim
Kim Miller-Tallman
– Bonner Springs, KS, USA
June 11, 2008