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How to get a smooth finish??

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rockets

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How do you guys do it? Where on cardboard tubes, you can't see the spirals, it's smooth, shiny and looks great!?
I tried searching for a thread that already exists on this topic, but didn't succeed.

Thanks,
 

Bat-mite

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Use various things like wood filler, bondo, wood glue with water, etc., to fill spirals. Sand and reapply as necessary. When sanding, continue to step up to higher and higher levels of granularity.

Once you have a very smooth surface, use filler-primer to fill any remaining impressions in the material. Sand and reprime until you have no dingleberries or roughness.

Then, apply several coats of top paint. Sand and repaint as necessary. Finally, apply decals and several coats of clear coat.

(Note: I don't do any of this. I just glue them together, throw some paint on, and go launch.)
 

neil_w

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Chris Michielssen had a good article in the most recent Apogee Peak of Flight newsletter regarding filling of tube spirals.

For LPR stuff it really doesn't take much time or effort once you get the hang of it.
 

Micromeister

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If you really want to get the info needed to create babies butt smooth finishes using only rattle can products
Please visit www.narhams.org from the left hand menu find the library section, click on it then click on the Tech Tip folder.
down load Tech Tip-002 through 005. These have recently been updated with new info & products making it possible for anyone to create Babies butt smooth Model to HPR rocket finishes.

Just a hint: Finishing can take 4 times as long as it does to build anything. From Homes to Model Rockets Finishing is a time consuming task. Each Rocket builder must decide how much time to allot to finishing our rockets. As stated above some modelers don't worry about what the rocket looks like close up, but rather how they fly.
 

CPUTommy

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A few things I learned from my dad who did body work his entire life, back in the days of spraying laqueor with no masks, I grew up keeping the floor wet while he painted.
1-the fiinish is directly affected by the prep!
2-the finish is directly affected by the humidity,and air temp
3-speed painting is the best way to ruin a finish

How I've overcome a few things,
- I use a cardboard dryer box as a make shift spray booth, it works great, a big opening and a square hole in the back with A fan pulling air out of the box (not to close you want air flow not a wind tunnel
- I use an old school heat lamps to increase the temp of the box, I spray then move lamp into the big end to being the temp back up.
- I rotate the rocket the entire time to get temp even on whole rocket.
- I always spray a base coat of white!! It allows you to see the imperfections where as the primer sometimes hides the imperfections, I'll fix what needs to be fixed and re base coat until it's what I want.
- I soak the rattle can in the hottest tap water I can get and that helps the paint as well as the psi of the rattle can.
- I will sand with 400 grit, and 600 grit then 1000 grit and then clear coat the rocket, the clear coat is the real bitch, it does NOT behave like paint!! Add 6 inches of distance from your paint vs clear, the clear will run like you can't imagine, many light coats 5 minutes apart usually works (and keep rotating the rocket)

Remember, your prep is MORE important than your final coat.
 

ksaves2

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PITA, entails filling, primer, painting, wet sanding, clear coat, a bunch of wet sanding with progressively finer paper, rubbing compound, polishing compound
and car wax. Oh, remember NOT to sand through the clear coat. You'll get a rattle can finish that looks like waxed car paint but don't get any acetone on it!
Do that and it'll strip the "hard work" enameled paint right off!
Wet sanding a cardboard tube is a lot of fun!! Kurt
 

rockets

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I tried it yesterday for the first time; I used Elmer's wood filler which really worked well. After that dried, I sanded it down with 360 grit sandpaper. And then I felt it, and it was very smooth.
After painting, you can't even see the spirals.

Thanks,
 

CPUTommy

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I use 180 grit (my favorite) then 220, prime, re fill what needs to be addressed, sand again, prime.. sand.. prime.. base coat.. fix.. repeat..

ANY IMPERFECTION you can see will be magnified with the top coat.

Also, bring the rocket outside and use the natural sun light, I have a pencil and circle the areas that the sun shows me. In door light can plan wicked tricks on you.
 

AfterBurners

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I use 180 grit (my favorite) then 220, prime, re fill what needs to be addressed, sand again, prime.. sand.. prime.. base coat.. fix.. repeat..

ANY IMPERFECTION you can see will be magnified with the top coat.

Also, bring the rocket outside and use the natural sun light, I have a pencil and circle the areas that the sun shows me. In door light can plan wicked tricks on you.
plus 1
 

Nathan

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i have a feeling nathan might be implying to check otu some of his threads.

you'll learn a lot from them, andrew.
To be fair, I haven't done a cardboard tube build thread in a long time, and the old threads all had Photobucket images which no longer display since Photobucket stopped allowing 3rd party hosting. I haven't yet gotten around to moving all those images to Flickr.
 

CPUTommy

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when I dont "rush" my paint jobs.. they come out ok..

These pics are just regular rattle can paints, rustoleum primer, base and top coats.

Ive started using new paint though..its custom spray paint, Its automotive paint that they put into a rattle can. Very expensive but thats me and most of you guys wouldn't consider this paint or its cost.

4.jpgj.jpgn.jpgIMAG0397.jpgView attachment 325490
 

stealth6

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One thing I learned during my lutherie and furniture making days........there are NO products or methods of finishing where you can simply apply and end up with a perfectly smooth finish. If you want a truly high quality result, you must "finish the finish". . By this I mean that once your paint or whatever is applied and cured, you then do the real work of leveling/sanding/polishing/buffing that "finish". Yes, pre-prep (before applying any paint) is hugely important, and you won't get good results without a lot of attention and care devoted to it. But if you want a "perfect" finish, time and effort spent AFTER you apply your paint is necessary to get you there. And this step is rarely if ever paid attention by most hobbyists.

Now this is probably way overkill for the finishing level of most rockets, but it's good to understand the concept at least.


s6
 

rockets

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Another question:
What should I put on it to protect the paint, give it some shine, and make it nice? (NOTE: I'm talking about AFTER I'm finished painting.
Thanks,
 

neil_w

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I find that Future floor polish, applied by foam brush, is just about the easiest way to get a good gloss coat. The actual stuff is called "Pledge Floor Care Finish" these days. Brush it on, then hang the rocket vertically, and the excess will drip off the pointy bits (I hang it over a garbage can). Dab the drippy bits with a paper towel once in a while until it stops. I usually stop at one coat, but some apply more.

Recently, John Pursley has waxed enthusiastic about Minwax Polycrylic spray, but I haven't tried it.
 

Rockiteer

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Great stuff Andrew. Thanks. Was goofing around with shellac and super-glue to fill in the groves on paper tubes. Shellac helps to seal the tube while the super-glue fills in the crevices. The only problem is that super-glue dries so hard and requires A LOT of sanding to even it out. Will most definitely try the Elmer's wood filler technique the next time out.
 

AfterBurners

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Nathan where are you master of all painters....

Nathan is the man!! When it comes to painting and getting smooth and glass like finishes...he is the best!
 

rcktnut

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I tried it yesterday for the first time; I used Elmer's wood filler which really worked well. After that dried, I sanded it down with 360 grit sandpaper. And then I felt it, and it was very smooth.
After painting, you can't even see the spirals.

Thanks,

Looking really nice, good job!! Just remember that no matter how much effort you put into finishing, unless your launching/ recovering on a sod farm, any other location will eventually screw up the finish anyway.
 

Nick@JET

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Just search for anything from Nathan or Von Moses - there are others but their techniques are well documented.
Think of dullness as Snow Moguls if you have ever been skiing, the bumps get worse and worse. So sanding the bumps down at every step will
Make a shiny smooth surface.

After you apply a coat - there has to be enough coating that when you sand down the final time there has to be enough coating that the bare rocket is not visible.
Realize you're waiting for coating to be dry in order to sand or it will ball up - so this takes patience and lots of sand paper, that's the hard part
So basically - prime , sand with 220 until fairly smooth
Prime , sand with 400 until smooth
Prime then wet sand 600 until smooth now your ready for color coat.

Color coat lightly in 3-5 layers - don't lay it on thick until last coat then I make the last coat wet but not runny. Let dry and wet sand 600 - then 1000 (this will look splotchy- this is the bumps in the paint not on the same level - once splotches are almost done you're done with 1000) - careful with edges as the sandpaper will take off the color and your in trouble.
This is where I lay on clear - but optional - you don't need clear for a reflective shiny paint job.

Now moving on to 2000 wet (your looking for the splotches completely gone and will start to feel very smooth and the shine starts - be careful not to load up sand paper or 2000 will turn into 600 and your shine is gone)

then swirl remover wax - this starts shining. Start looking at your reflection and if it's a Nathan rocket there won't be a haze or waviness - if you can read words clearly in reflection you haven't gone far enough

then wax ( this is where you better have enough color thickness) .

FYI - The shine doesn't start happening until late in the 2000 grit or swirl remover.

I'm definitely not one for patience Donny rockets look ok at 5-10' but I've done 2 rockets with those techniques that turned out beautiful only to have road rash in transport. So socks are your friend.

That's my 2 cents - the polishing is a process so enjoy the process - if you're in a hurry to fly the rocket you will never get a smooth shiny rocket - so think of building one rocket to achieve this and you'll fly it in a few months or next year and fly the rest while your working on that one.
 

lcorinth

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I tried it yesterday for the first time; I used Elmer's wood filler which really worked well. After that dried, I sanded it down with 360 grit sandpaper. And then I felt it, and it was very smooth.
After painting, you can't even see the spirals.

Thanks,
Great work! I use that stuff all the time. People sometimes tell me it's not worth the effort, but it doesn't really take that long and I like the way it looks.

Good job!
 

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