Finishing a Loc Nose or, "How to Finish a Loc Nose?"

[gary7]

I really like Loc kits and parts. About the only issue I have is the nose cone mold seam. This one also has a couple of mild imperfections.

Question: how do you fill and finish these?

I have used Bondo Glazing and Spot Putty on these with some success. But I recently ruined a nose by just a bit of over sanding. Wasn't able to get the fuzz off even going thru the numbers down to 600 grit. Paint job shows it. In fact it's ugly.

Before paint, I use Duplicolor wipes and Adhesion Promoter Primer. That Bondo glazing will adhere to primers rather well too although I have not tried it on the adhesion promoter that I can recall.

 

[David Schwantz]

1st, I'll scrape with exacto blade to get it as smooth as possible. Then many coats of just primer, and sand most of it off.

 

[Troy3003]

I do like they said above and razor off the excess. Lightly sand the whole thing, wash/dry it. I do use the ready to apply spot putty, althougb I don't care for it much. For me the important thing was to use a firm block when sanding. I'll sand just to where I can almost see nose material showing through and stop there. Clean up any excess spot putty outside of the sanding area then primer, sand, primer till you are happy. It helps to use a different shade of primer on alternate sandings to help see where you are at.

 

[jd2cylman]

I lightly go over the whole cone with a butane torch. Lightly sand and it seems to change the surface enough to let paint stick.

 

[Budro0]

My go-to is actually a heavy grit (80-120) sandpaper to smooth manufacturing seams and defects. I then use a plastic adhesion promoter and a high build primer/filler and sand with a 200+ grit. This gets rid of the fuzzies and gives me an idea of deeper gouges that will need to be filled with the spot glazing putty. After the putty and another coat of filler/primer, I continue the process of sanding and repriming until I get a nice smooth finish. I plan 5 or 6 coats to get a nice even finish for final coats.

 

[ThirstyBarbarian]

Are you hoping to slay the mysterious LOC Nose Monster?

These nose cones are definitely a pain. Paint does not like to stick, and sanding causes some problems of its own. I shaved the seam down with a sharp blade, and then sanded the whole cone very lightly with a fine sand paper. It does raise some fuzz, but if you spray it with some filler primer, sand, filler primer, sand, etc. you will get rid of the fuzz. Eventually you can get a smooth cone that will take paint, but it’s a bit of work.

 

[gary7]

I thank everyone for their input. I did not intend to bash the Loc nose cones. I have found a way to get paint to stay on the Loc noses. I like them. They are versatile enough to do different things with, without breaking the bank on fiberglass or carbon fiber. Built, flown and recovered properly, Loc products (itemized and kits) are a very good way for people to get into mid to high power flying.

Thanks again for input.

 

[dr wogz]

I am somewhat amazed that we (the rocketry community) haven't taken to rakes & pitchforks to "demand" our nosecone suppliers start using a more "finish friendly" plastic to mold these from..

I get why they use this particular type of plastic, but we all tend to complain about the same thing with these!

 

[PayLoad]

... They are versatile enough to do different things with, without breaking the bank on fiberglass or carbon fiber. ...

It all depends on how much your time is worth. 15 hours spent on a $10 nosecone? No thank you, I'll spend $40 and have it come out of the box ready to go

 

[RobertH3]

Sanding Block with 150. Sanding Block with 220. Sand Sand Sand lol. Adhesion promoter then primer then putty.
The polypropylene has a low surface energy which means if ya put nose weight in, you need dowels through the tip so the epoxy can stick to something. Adhesion promoter for the paint for the same reason. LOC isn't the only company that provides these!
On the plus side, when my mini-magg crashed - it was 6.5 lbs on a 15" drogue and hit the blacktop - also had a pound of BB's in the nose. Didn't break although it had a combo of road rash and leprosy, and some paint exploded off the surface. Actually pretty stout.
They are a pain but inexpensive.

Cheers / Robert

 

[crossfire]

I have kind of have up and dont worry about the seam showing anymore. I just clean up the seams and give it a couple of primer coats. Most of my rockets are for flying not a show rocket. You won't see the seams from 10' away.

 

[Back_at_it]

I use a hobby knife to remove the bulk of the parting line. After that I use Red Scotch Bright pad on it with some dish soap.

For painting it starts with Duplicolor adhesion promoter. Two cost of that then SEM Filler Primer.

The fuzzy stuff is common. Just do two or three coats of filler primer and sand with 400 in between coats. It will eventually go away. If you have already painted, let the cone dry for a couple of weeks then sand it and reshoot it with the same paint.

 

[Troy3003]

Here is my last Loc nose cone. Turned out pretty good. I've since put a coat of clear and wet sanded/buffed. I had zero adhesion issues.

 

[crossfire]

Here is my last Loc nose cone. Turned out pretty good. I've since put a coat of clear and wet sanded/buffed. I had zero adhesion issues.View attachment 471641

You probably won't have any issues untill it hits the ground. It seem like when cone flexes that's when paint cracks and comes off. My cones that are foam filled seem to hold up much better.

 

[Troy3003]

Its been up twice without issue, if it comes in hard or nose first I can't really blame the paint or the nose material.

 

[gary7]

more "finish friendly" plastic to mold these from

What do you have on mind?

 

[Back_at_it]

You probably won't have any issues untill it hits the ground. It seem like when cone flexes that's when paint cracks and comes off. My cones that are foam filled seem to hold up much better.

I've not had any issue with paint flaking off even when dropped IF I use adhesion promotor. Sure it will chip and scratch. I was in a hurry once and painted the nose cone to 4in. custom build. I forgot the adhesion promotor dropped the cone and got large sheet of paint to peel off. Wasn't happy but easy enough to correct.

 

[RobertC]

I had some difficulty finishing the nose on the LOC 4" Phoenix I'm building right now. The molding seams on mine were indented in past the surface and were also raised in some areas. I trimmed the raised parts down with a razor knife, then sanded with 150 for a while. After quite some time sanding, I realized that it was going to be tough to get down to the lowest point in the seams. What I ended up doing was spraying the seam with plastic adhesion promoter and filling the low spots with Squadron White Putty. Then for paint I sanded the whole surface with 220 grit, sprayed a few coats of adhesion promoter, and then sprayed with filler primer. When I sanded that smooth, I ended up sanding through the primer in some spots, so I spot sprayed adhesion promoter again on the exposed plastic and put another coat of filler primer on. I was able to sand that coat without sanding through to plastic, then I just painted as normal over that. It seems to have adhered pretty well, but it hasn't hit the ground yet. It was quite time consuming, so I hope it stuck as well as I think it did.

 

[dr wogz]

What do you have on mind?

haha, open ended question!! I have no idea, but I'm sure a chemical / plastics engineer can come up with something that suits our needs (wants?) and is easily 'blow molded'..

 

[jimzcatz]

Not really sure what I'm doing differently, but I have never had an issue with Loc noscones. I put them on a belt sander and standard Walmart gray primer. Granted i'm not as an*l as most of you regarding my finishes.