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Helping me Paint a Polyurethane nosecone successfully?

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ColumbiaNX01

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Hey everyone. I have a problem I have always had trouble painting polyurethane nose cones from Aerotech, LOC, and Madcow. This last time I had some to paint, I used Valspar clear plastic primer 2 coats then 2 coats of Valspar gloss back. When it was all said and done the paint still flacked off when anything rough touched the nose cones, for example my finger rubbbing against the nose cone. I painted them in room temperature conditions and waited 15 minutes between coats of primer than I painted the black paint the next day and waited 15 between two coats and let it sit in room temperature for a few days and here I am now, the paint peels off.

Am I missing anything, everything I did, I told you in the paragraph above. Is there anything that you guys suggest I do to get a good qaulity paint job on polyurethane nosecones??? I figure the paint I am using is from Lowe's and it is quality paint. I am wondering if I am missing something when I am preping the nosecones before paint.
 

davalf

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My father in law is quite the painter and he painted my last rocket. I told him that there was a possibility that the paint would not stick the plastic nose cone. He told me to leave it un-primered and he had some sort of adhesion helper. I do not know exactly what the stuff is called but it worked great. He sprayed the untouched nose cone with that stuff, waited 5 min, and then primered. It worked great. I would suggest calling a paint store, one that carries automotive paint, and ask them for something that does this. Hope this helps.

Dave
 

Handeman

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The plastic paints and primers are a great suggestion. It's what I use. I also wash the nosecone with soap and warm water to get as much of the mold release agent off as possible. Then I use a course sand paper and rough up the surface so the paint has something to stick to. The only time I've had paint fine off my nose cones is when the rocket fell flat without a chute and the nose cone slammed sideways into hard ground or gravel, but that was before I started using the plastic paint or primer.
 

ColumbiaNX01

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I do not know why that does not work because I took my nose cones and sprayed plastic primer on them and then painted them with red paint and then the paint still flaked off. I scraped all the paint off the nose cones with a knife and then washed them with hott soapy water and then painted them with 2 layers of plastic primer then 2 layers of red paint. The same result happend the paint still flakes off. I do not know what to do because after I used the knife to get the paint off it scraped up the nose cones so that there was a rough surface for the paint to adhere to, but I do not know what to do. I used Valspar Plastic Primer then Valspar regular red paint. It still not succesfull. I need help!!!!!
 

El Phantasmo

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I haven't had any problems with them. I sand, prime, paint and then clear coat.
 

ColumbiaNX01

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Well that does not help! Should I try some of the plastic primers and paint that are used for automotive plastics?
 

kandsrockets

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I haven't had any problems with them. I sand, prime, paint and then clear coat.
Same thing I do. I wet sand with 600 paper in a bucket filled with water and ivory dish soap. I rinse and let dry. I primer with dupli color hi build primer. Paint and clear coat and have not had problems with paint coming off.
 

dixontj93060

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One additional step helps even more. Before the high-build primer, I spray the nosecone lightly with Dupli-Color Adhesion Promoter.

Same thing I do. I wet sand with 600 paper in a bucket filled with water and ivory dish soap. I rinse and let dry. I primer with dupli color hi build primer. Paint and clear coat and have not had problems with paint coming off.
 

slogfilet

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I've had good results with washing the NC, then scuffing with 100 or lower grit, then using Krylon Fusion before priming.

As was noted by someone previously, the dry time for plastic primers can be MUCH longer than regular spray paint. It says it may be "dry" within 24 hours, but full chip resistance will take 7 days. I always wait at least a week.

How long did you wait before adding paint on top of the plastic primer?
 

exprditer789

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Try using bumper coating for your primer for plastic.It worked great for me.It is made for plastic and is pretty durable because it is made for front of cars.I also wash it off with water and soap while sanding it before applying any kind of paint.If you sand it with no water it might push the release agent in more.
 

Pantherjon

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Are you sure the cone is made from polyurethane and not polypropylene?

Polypropylene is what they make milk jugs out of, and there are a few places that make nosecones out of it as well, Paint will not stick to it very well at all.
 

sodmeister

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Some good tips here ,although I have not had too many problems with adhesion for the most part ,as I usually fly on fields and no crash landings on pavement/gravel.Too bad more manufacs. don`t use styrene more ,but I suppose it may be a durability/impact /shattering issue.

Paul
 

MattieShoes

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On my first aerotech kit, I simply sanded the worst of the imperfections away, washed it off, and painted a few coats of rattle-can testors directly on the NC, then a couple coats of clearcoat. It doesn't fine at all, though imperfections in the nose cone are still visible to close inspection... KISS principle works great if you're going for "good enough" rather than perfect.
 

vdotmatrix

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I am at the painting stage on my Aerotech Arreaux and i found the nose cone paint coming off if i even look at it funny.

I am using acrylic air brush paint.

I am going to finish this thing off with a coat or 2 of Pledge Floor finish with FUTURE(formally known as Future Floor Finish ) and hope the thing gets locked off in an acrylic hard shell once this clear coat dries.

I am not expecting the paint to stay on and won't be disappointed if it comes off but will take it from there if it does...
 

cmcain

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i rough up my nosecones with 100 grit sandpaper and get them rough where there are little plastic hairs sticking up everywhere then i wach them with soap and water and prime them heavily with duplicolor high build primer and wet sand with 220 grit, i reprime and wetsand one or two more times finishing with 400 grit and then ill spray my color and clear, my nosecones come out very smooth and almost glass like infact the only one that i had trouble with was my iroc but it also came in ballistic from 3200' on a j350 when the ejection charge failed
 

TRA3180

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i rough up my nosecones with 100 grit sandpaper and get them rough where there are little plastic hairs sticking up everywhere then i wach them with soap and water and prime them heavily with duplicolor high build primer and wet sand with 220 grit, i reprime and wetsand one or two more times finishing with 400 grit and then ill spray my color and clear, my nosecones come out very smooth and almost glass like infact the only one that i had trouble with was my iroc but it also came in ballistic from 3200' on a j350 when the ejection charge failed
True Story!

In fact Chris also "Planted" one of his smaller rocket's in my corn field! :y:
He had to dig out the nosecone with a shovel!
Absolutely no scratches in the paint!
The shoulder on the other hand we had to heat up to reform it so it would fit into the airframe.

He paints all my nosecones now!
If he has time in between all the rocket projects he has going at the same time! LMAO!
 

o1d_dude

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Yup. It's the little "hairs" that you raise up with the 60-80-100 grit that provide the anchor for the primer coat.

I've been using the Rustoleum Plastic Primer on my nosecones lately. It's white regardless of the color of the rattlecan cap. You have to follow the instructions and let the first coat cure for about a week before you mess with it. Also you will not be using the Plastic Primer again so set it aside for the next nosecone. One coat is all you need.

From this point forward you use your regular primer and paint process. I stick with Rustoleum primers and paints and have had no issues with paint compatibility.
 

fish701

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When I finish all of my rockets, I start off sanding the nose cone with 100 grit. Then I coat the entire surface, body and nose cone, with watered down wood putty. This fills it the spirals on the body tube, and will attach to the "hairs" and groves you just put in the nose cone, giving the paint something other than plastic to adhere to. Let it dry, then sand with 100 grit. I do 2-3 coats of this. Usually finish sanding this with 220 grit, I think. Then I put on a couple coats of primer (whatever is cheap paint usually). I wet sand between coats of that. Then I put 3 coats of my main color on (again, wet sanding between coats). Followed by 2-3 coats of clear gloss. If I want it to be really shinny, I'll follow with the Future Floor, or even some car wax paste. Both work really nicely. Until I started using the wood putty, I had problems with the paint chipping off the nose cones. No longer...
 
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