The Path to Level 1: Acquisition, Build, Test, and Certification Attempt Thread

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Filling the spirals is similar to filling nail holes in a wall. You put filler into the hole in the wall and then you use your putty knife to scrape across it to remove all of the excess and leave a smooth surface. Filling the spirals works the same. Put a little filler along the spiral and then use your card or putty knife to scrape across the spiral, not along it. This will force the putty into the gap while removing the excess. Start at one end and do this all the way down to the opposite end. You'll be left with a filled spiral with only minimal sanding needed.

The other option is to just use high build sand-able primer like this (Rust-Oleum Flat Gray Spray Primer) to fill in the spirals plus cover the entire tube to get it ready for paint.
I see. Thanks for the information, that makes a lot of sense, actually. I haven’t done really any work with putty before (and I’ll sheepishly admit I haven’t done a lot of home handiwork outside of my few Estes kits), so this is all new.
 
I did a little bit of application and scraping this morning.

B9A94E85-F7A0-4E7F-B0A8-2EEAA0B745C6.jpeg

It’s nice that I can see the tube sticking through, it should be a quick sanding job. I’ve given up on guessing whether or not it will produce a workable final result, but I’ll say I’ve got a good feeling about this, even if that’s pretty far from looking neat.

I’ll pick up some 400 later.
 
The other option is to just use high build sand-able primer like this (Rust-Oleum Flat Gray Spray Primer) to fill in the spirals plus cover the entire tube to get it ready for paint.
^^^ This.

I use Duplicolor FILLER primer. Put it on heavy, sand smooth. Might have to do an additional coat if the spirals are real deep. I just finished up 2 rockets using it, and you can't see any evidence of the spirals at all. In addition, I put it on very heavy at body tube joints, and sand smooth.

It typically dries to the point of being sandable in under an hour.

Hans.
 
^^^ This.

I use Duplicolor FILLER primer. Put it on heavy, sand smooth. Might have to do an additional coat if the spirals are real deep. I just finished up 2 rockets using it, and you can't see any evidence of the spirals at all. In addition, I put it on very heavy at body tube joints, and sand smooth.

It typically dries to the point of being sandable in under an hour.

Hans.
Yeah, if the putty doesn’t come through today I’ll likely do that instead. I’m pretty tired of it not staying.
 
I did a little bit of application and scraping this morning.

View attachment 560906

It’s nice that I can see the tube sticking through, it should be a quick sanding job. I’ve given up on guessing whether or not it will produce a workable final result, but I’ll say I’ve got a good feeling about this, even if that’s pretty far from looking neat.

I’ll pick up some 400 later.
When I use Elmer’s Fill and Finish on cardboard tubes that’s exactly what it looks like. I mix in a little water and apply it with my finger, which smooths it out. Once it’s dry I just hit the spirals with sandpaper, coarse to take off the high spots and then fine to blend. I don’t think I’ve ever gone finer than 240 grit for this step. Primer and paint will fill in sanding marks from 240 grit.
 
When I use Elmer’s Fill and Finish on cardboard tubes that’s exactly what it looks like. I mix in a little water and apply it with my finger, which smooths it out. Once it’s dry I just hit the spirals with sandpaper, coarse to take off the high spots and then fine to blend. I don’t think I’ve ever gone finer than 240 grit for this step. Primer and paint will fill in sanding marks from 240 grit.

Every so often I look at this thread or my tubes and think “grrrr, it’s a tiny spiral groove running the length of a glorified carpet roller, how is this not just simple?”.

And then I leave it alone for a couple hours until I’m clear-headed and (over)confident again.
 
Yeah, if the putty doesn’t come through today I’ll likely do that instead. I’m pretty tired of it not staying.
Honestly, I can fill the spirals and have it primered ready to paint in less time than it previously took me to attempt to fill the spirals with CWF. The Duplicolor Filler sands really fast. I usually use 320 grit wet. The whole rocket gets sanded smooth in maybe 10 minutes max.

So.... From bare tube to primered tube to sanded tube in under an hour. About half the time I cover with a conventional sandable primer over the filler, but I'm not sure it makes any difference.

Hans.
 
The other option is to just use high build sand-able primer like this (Rust-Oleum Flat Gray Spray Primer) to fill in the spirals plus cover the entire tube to get it ready for paint.
I've long been in the "just use a lot of primer" camp of spiral fillers, but at the cost of primer these days, I may not stay in that camp much longer.
 
Well, plastic wood is out. It’s no more survivable with 400 grit than it is with 320. Since this is much finer than what other people are using, I’m calling it with that product.

Sorry, Plastic Wood. As far as I’m concerned, you’re defective. Into the trash you go!

I ordered Elmer’s Carpenter’s Wood Filler (Natural Indoor, 3.25 ounces) through Amazon and it showed up today. I popped off the cap, cut off a large portion of the applicator tip, and squeezed to test consistency.

Damp sawdust. Sticks to nothing, dries instantly. Useless in this state.

I took it to the sink and filled up the remainer of the bottle with water, then shook it until it felt mixed. I tried again and this time it came spurting out like milk. Not quite as useless, but still difficult.

3BE9B4EC-E002-4B00-ACE2-2298810D4719.jpeg

Even so, I figured that fiddling around with it further wouldn’t get me anywhere, so I set to work. Only one turn along the spiral, just like last time.

Between trying with my hobby knife and a Q-Tip, I’m not convinced that I got a sufficiently thick layer at any spot on the tube.

68453E0C-8158-4D33-A2EF-4C350300CD84.jpeg

The bottle is crimped shut like a toothpaste tube and it can only stand up on the cap, and I didn’t realize how inconvenient that is compared to the can of Plastic Wood and the classic Elmer’s White Glue Bottle. I can’t just set it down once I’m done dipping, I have to close it immediately.

What I’m going to do is leave the bottle open for an hour (leaning against the rocket’s box) and leave my handiwork overnight. I’ll try one more application and sanding with this stuff, but I don’t think I can afford to play around with it beyond that. The white layer of paper is starting to pull up at one end of the tube. If the next attempt doesn’t work, I’m giving up and proceeding with the build, and filling the spirals with the primer.
 
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Well, plastic wood is out. It’s no more survivable with 400 grit than it is with 320. Since this is much finer than what other people are using, I’m calling it with that product.

Sorry, Plastic Wood. As far as I’m concerned, you’re defective. Into the trash you go!

I ordered Elmer’s Carpenter’s Wood Filler (Natural Indoor, 3.25 ounces) through Amazon and it showed up today. I popped off the cap, cut off a large portion of the applicator tip, and squeezed to test consistency.

Damp sawdust. Sticks to nothing, dries instantly. Useless in this state.

I took it to the sink and filled up the remainer of the bottle with water, then shook it until it felt mixed. I tried again and this time it came spurting out like milk. Not quite as useless, but still difficult.

View attachment 561595

Even so, I figured that fiddling around with it further wouldn’t get me anywhere, so I set to work. Only one turn along the spiral, just like last time.

Between trying with my hobby knife and a Q-Tip, I’m not convinced that I got a sufficiently thick layer at any slot in the tube.

View attachment 561598

The bottle is crimped shut like a toothpaste tube and it can only stand up on the cap, and I didn’t realize how inconvenient that is compared to the can of Plastic Wood and the classic Elmer’s White Glue Bottle. I can’t just set it down once I’m done dipping, I have to close it immediately.

What I’m going to do is leave the bottle open for an hour (leaning against the rocket’s box) and leave my handiwork overnight. I’ll try one more application and sanding with this stuff, but I don’t think I can afford to play around with it beyond that. The white layer of paper is starting to pull up at one end of the tube. If the next attempt doesn’t work, I’m giving up and proceeding with the build, and filling the spirals with the primer.
Spray on some Duplicolor Filler? You'd be done by now.

Hans.
 
Spray on some Duplicolor Filler? You'd be done by now.

Hans.
Kinda baffles me that there isn’t a list of suggested brands/products in the instructions. I mean, it kinda makes sense given that this kit came out in the…90s I think?, and such products don’t remain in production indefinitely, but come on. I think most people would be able to figure out a modern replacement if they had a few keywords.

I kid you not, the instructions just say “a filler material”, so off I go, running to The Home Depot buying stuff meant to fill nail holes and not grooves that can barely catch my fingernail.

I guess they figured whoever was building this might have done some detailed scale work before, or took similar care with sport rockets, and thus probably figured out a workable technique long prior. That’s not a bad assumption, it’s just not a correct one for me. No disrespect meant to AT or their people, I’m just well past the point where I should have taken a break.

Full offense meant to DAP Global though, Plastic Wood has failed me at every turn.
 
Actually you know what? I’m just going to skip to the primer. It’s meant to stick, it’s supposed to be messy, and if I get the right one, it’ll be sandable. Sounds like it’s noob-proof. I’m going to look around at my options tonight, although I think any actual spray work will have to wait until I can get some tape to cover up the rail guides
 
Actually you know what? I’m just going to skip to the primer. It’s meant to stick, it’s supposed to be messy, and if I get the right one, it’ll be sandable. Sounds like it’s noob-proof. I’m going to look around at my options tonight, although I think any actual spray work will have to wait until I can get some tape to cover up the rail guides
Just make sure it's FILLER. Even "sandable" primer won't be thick enough to fill spirals.

And it's not really messy at all. I even sand it down standing over the kitchen sink. Really bad seams, like where 2 body tubes join, often need an extra coat or two.

Hans.
 
Just make sure it's FILLER. Even "sandable" primer won't be thick enough to fill spirals.

And it's not really messy at all. I even sand it down standing over the kitchen sink. Really bad seams, like where 2 body tubes join, often need an extra coat or two.

Hans.
Got it.

In that case, the one in my garage will likely not be suitable. It’s Rust-oleum Painter’s Touch 2x Ultracover Primer, Flat White. The cap is mismatched.

9F726AD4-4732-418E-A335-C5086827CE85.jpeg

Hi ho! Hi ho! It’s off to the store I go! Tomorrow though, probably….
 
1) If I was going to build directly on a cardboard tube, I would likely seal the fibers with some sort of sealer compatible with my finishing system FIRST, so as NOT to suck the solvent out of the filler/primer/topcoat too quickly.

2) Filler - I LIKE the old-fasjioned wood fillers with VOC solvent (specifically Acetone). I can add more, too much? Wait. Especially on cardboard or MDF, I prefer the NON-water-based fillers.

3) Albeit, once you are sealed/cured one layer or so, you can switch to highly filled water-based glazes, or stay with organic solvents. I'm looking into 30 micron borosilicate glass spheres and a chosen binder. Trying to blance weight against thermal performance, etc.
If I was gonna fill grooves, I'd use organic solvent based wood product and pull BACK on the groove, not across. Let it shrink and cure... hist it with a quick sanding to smooth, and fill again.

ONLY sanding blocks verified to be dead flat/smooth. And since I completely sealed the tube, I can judiciously wet sand once I have a good build.


My ONLY reason for caring about finish? At all?

All things considered, a smooth, true rocket flies straighter, faster, higher,and cooler per unit mass of propellant.
 
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A friend of mine once said "at 100 plus feet away and 200 plus mph, nobody is gonna notice the flaws." Unless your a perfectionist or have been commissioned by a museum, don't over think it. I have over thought a build or a paint job and it ends up sitting for months or longer. Thats just stupid and or laziness on my part. Build, paint, fly it, life's too short,
 
1) If I was going to build directly on a cardboard tube, I would likely seal the fibers with some sort of sealer compatible with my finishing system FIRST, so as NOT to suck the solvent out of the filler/primer/topcoat too quickly.

2) Filler - I LIKE the old-fasjioned wood fillers with VOC solvent (specifically Acetone). I can add more, too much? Wait. Especially on cardboard or MDF, I prefer the NON-water-based fillers.

3) Albeit, once you are sealed/cured one layer or so, you can switch to highly filled water-based glazes, or stay with organic solvents. I'm looking into 30 micron borosilicate glass spheres and a chosen binder. Trying to blance weight against thermal performance, etc.
If I was gonna fill grooves, I'd use organic solvent based wood product and pull BACK on the groove, not across. Let it shrink and cure... hist it with a quick sanding to smooth, and fill again.

ONLY sanding blocks verified to be dead flat/smooth. And since I completely sealed the tube, I can judiciously wet sand once I have a good build.
I’m not even going to pretend I understand all of the chemistry. It sounds fascinating but I don’t even know where to begin in figuring it out.

On the other hand, spray can goes pssssshhhhhhh! and will probably do what I want without a bunch of fuss. That works for me. Maybe I’ll jump into the physical and chemical properties of wood fillers at a later date, it’s just so far removed from what I’m trying to accomplish here.

A friend of mine once said "at 100 plus feet away and 200 plus mph, nobody is gonna notice the flaws." Unless your a perfectionist or have been commissioned by a museum, don't over think it. I have over thought a build or a paint job and it ends up sitting for months or longer. Thats just stupid and or laziness on my part. Build, paint, fly it, life's too short,

Lucky me, I’ve got no deadline, and I’d like this to look nice. It is a scale model, after all. If it were just a sport rocket I probably wouldn’t bother.
 
1) If I was going to build directly on a cardboard tube, I would likely seal the fibers with some sort of sealer compatible with my finishing system FIRST, so as NOT to suck the solvent out of the filler/primer/topcoat too quickly.

2) Filler - I LIKE the old-fasjioned wood fillers with VOC solvent (specifically Acetone). I can add more, too much? Wait. Especially on cardboard or MDF, I prefer the NON-water-based fillers.

3) Albeit, once you are sealed/cured one layer or so, you can switch to highly filled water-based glazes, or stay with organic solvents. I'm looking into 30 micron borosilicate glass spheres and a chosen binder. Trying to blance weight against thermal performance, etc.
If I was gonna fill grooves, I'd use organic solvent based wood product and pull BACK on the groove, not across. Let it shrink and cure... hist it with a quick sanding to smooth, and fill again.

ONLY sanding blocks verified to be dead flat/smooth. And since I completely sealed the tube, I can judiciously wet sand once I have a good build.


My ONLY reason for caring about finish? At all?

All things considered, a smooth, true rocket flies straighter, faster, higher,and cooler per unit mass of propellant.
Have you actually tried an automotive type filler/primer? It's a lot simpler than what you are specifying and it does deliver a glass smooth surface after sanding.

Hans.
 
Have you actually tried an automotive type filler/primer?
+1 on the auto primer. High build stuff has worked well for me. Put a layer on, sand almost all the way to the surface, it’ll only stay in the low spots (like the spirals).

Just have a brass brush for your sandpaper, it really loads the sandpaper up.
 
I took [the CWF?] to the sink and filled up the remainer of the bottle with water, then shook it until it felt mixed.
Assuming you got the right stuff (what I recommended comes in a tub, not a bottle) you have to add water in small amounts until you get the desired consistency. You can't just dump in some random amount and hope for the best.
 
Assuming you got the right stuff (what I recommended comes in a tub, not a bottle) you have to add water in small amounts until you get the desired consistency. You can't just dump in some random amount and hope for the best.
Yeah, no. It’s a little tube a few inches long with a toothpaste tube end and a screw off cap. I’m kicking myself for that now because I saw it on the product page and didn’t think that through.

F8836C23-A6BC-4B18-8191-991DD6E3D50E.jpeg

But even so, the payload bay tube is starting to lose its outer layer and I’d rather find something simple and workable before it loses too much more. That’s more important to me than mastering any one particular method.
 
Assuming you got the right stuff (what I recommended comes in a tub, not a bottle) you have to add water in small amounts until you get the desired consistency. You can't just dump in some random amount and hope for the best.
Yeah, the mix ratio can be a little picky. Although I don't use it for body tubes, it's still a choice (although not the only one...) for wood. Especially to smooth over plywood fins if the wood quality is iffy before using Duplicolor Filler. I've been getting fins from Jbassham on Ebay, and I just jump straight to rattle can, as his wood is quite smooth.

Hans.
 
CWF: take a blob of it, put it in a small dish, and add water and mix until you get the thickness you want. There's no way you could mix it correctly in a tube, squeeze some out and mix it outside the tube.

And remember, it's a hobby and it's supposed to be fun. If it helps, you'll get your L1 (or not) regardless of how well your spirals are filled (or not.) :)
 
CWF: take a blob of it, put it in a small dish, and add water and mix until you get the thickness you want. There's no way you could mix it correctly in a tube, squeeze some out and mix it outside the tube.

And remember, it's a hobby and it's supposed to be fun. If it helps, you'll get your L1 (or not) regardless of how well your spirals are filled (or not.) :)
Not to be a debbie downer but + what he said. If you lose or crash your Lvl 1 rocket you will regret it for the rest of your life. or maybe im just a pussy and cry at movies :)
 
And remember, it's a hobby and it's supposed to be fun. If it helps, you'll get your L1 (or not) regardless of how well your spirals are filled (or not.) :)
True. I'm doing finishing touches on yet another MPR, and there is a bit of orange peel in the nose cone paint. I've been stewing over it, but, you know, from 3 feet away, you can't see it.

Screw it! Stuff a motor in and hit the button.

Hans.
 
And remember, it's a hobby and it's supposed to be fun. If it helps, you'll get your L1 (or not) regardless of how well your spirals are filled (or not.) :)
That’s precisely why I got started on another build (an Estes Twin Factor). I didn’t want to end the build night feeling sour
 
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