Banishing Tube Spirals

[brockrwood]

I just finished applying “Tube Spiral-B-Gone” (Elmer’s Wood Filler).

I may have overdone it a bit.

One day to work on rockets before busy work week. Work is overrated.

 

[neil_w]

I just finished applying “Tube Spiral-B-Gone” (Elmer’s Wood Filler).

I may have overdone it a bit.

A bit.

Just use your finger to wipe away the excess while it’s still wet and you’ll save yourself a ton of sanding.

Also it is *much* easier to sand the spirals if you do it all before attaching anything to the tube (e.g. fins).

One day to work on rockets before busy work week. Work is overrated.

Agreed!

 

[Hobie1dog]

Like the guy on here who has below his avatar, the saying, "I don't do spirals"

 

[brockrwood]

A bit.

Just use your finger to wipe away the excess while it’s still wet and you’ll save yourself a ton of sanding.

Also it is *much* easier to sand the spirals if you do it all before attaching anything to the tube (e.g. fins).

Agreed!

Great tips! Thanks!

 

[brockrwood]

Great tips! Thanks!

@neil_w is right, as usual. You need to wipe off excess wood filler before it dries. This is how far I have gotten after sanding with 320 grit sandpaper. Sigh.

 

[neil_w]

@neil_w is right, as usual. You need to wipe off excess wood filler before it dries. This is how far I have gotten after sanding with 320 grit sandpaper. Sigh.

Live and learn!

Another approach (other than fingers, although fingers are what I always use) is to squeegee off the excess with a credit card or something. I usually don't do it this way because I find it too frustrating to try to keep the credit card perpendicular to the body tube while rotating the tube. Possibly some sort of flexible (but stiff) squeegee might work better.

 

[Raythain]

My LPR technique is to take unthinned CWF and run it down the spiral with my finger. After I get to the bottom of the tube, I use my finger or hand to rub perpendicular to the spiral to “sand” off the rest of the filler.

I don’t even take sandpaper to it until I shoot it with a high-build auto primer. Of course, I spend a long time sanding that, so YMMV.

Really seems that if you want better than a 30 foot finish, you need to pick a point and say “Now, at this step we spend forever with a piece of sandpaper getting a nice smooth surface.”

 

[brockrwood]

My LPR technique is to take unthinned CWF and run it down the spiral with my finger. After I get to the bottom of the tube, I use my finger or hand to rub perpendicular to the spiral to “sand” off the rest of the filler.

I don’t even take sandpaper to it until I shoot it with a high-build auto primer. Of course, I spend a long time sanding that, so YMMV.

Really seems that if you want better than a 30 foot finish, you need to pick a point and say “Now, at this step we spend forever with a piece of sandpaper getting a nice smooth surface.”

I am willing to accept, say, a 15 foot finish, or whatever the length is for a standard Estes launch controller.

 

[Rob Campbell]

The best way to deal with spirals.

 

[brockrwood]

Primer on.

 

[BABAR]

I like the candy cane technique.

Initially, ignore the spirals and build and finish the rocket. Use electrical, vinyl tape (because it stretches and deforms easily, a flat ribbon like tape cannnot form a true cylindrical helix) and wrap it around covering the spirals. Since the tape domes in numerous colors, you can often come up with a nice complementary paint scheme.

Fin areas do get a little tricky. But combine this with papered fins and a plastic nose cone and you have little if any sanding.

 

[SolarYellow]

Just go to here http://modelrocketbuilding.blogspot.com/ and search "spiral." He's the master at dealing with stuff like this.

 

[brockrwood]

I like the candy cane technique.

Initially, ignore the spirals and build and finish the rocket. Use electrical, vinyl tape (because it stretches and deforms easily, a flat ribbon like tape cannnot form a true cylindrical helix) and wrap it around covering the spirals. Since the tape domes in numerous colors, you can often come up with a nice complementary paint scheme.

Fin areas do get a little tricky. But combine this with papered fins and a plastic nose cone and you have little if any sanding.

I wonder if I could use vinyl electrical tape (just the cheap, black stuff) as a masking tape to make a candy cane effect using a second spray paint color?

 

[BABAR]

I wonder if I could use vinyl electrical tape (just the cheap, black stuff) as a masking tape to make a candy cane effect using a second spray paint color?

Absolutely. I thought about adding this option.

Thing is, with either you will still SEE the spirals, but they become SO noticeable that they paradoxically disappear.

 

[user 30299]

I use a battery-powered toothbrush to sand the wood filler for the spirals. Came across this suggestion somewhere years ago.

Made the sanding a good bit easier, and also kept the sanded area right to the spirals.

The pictures pretty much explain it all. Bought an inexpensive toothbrush at Walmart. Trimmed off the brushes.
Used adhesive-backed sandpaper to make up the little sanding squares. I have a couple of different grits too.

 

[KenECoyote]

I just thought of something...

Has anyone ever tried string or floss (unwaxed) glued into the spirals?

I might try that this week.

 

[brockrwood]

I use a battery-powered toothbrush to sand the wood filler for the spirals. Came across this suggestion somewhere years ago.

Made the sanding a good bit easier, and also kept the sanded area right to the spirals.

The pictures pretty much explain it all. Bought an inexpensive toothbrush at Walmart. Trimmed off the brushes.
Used adhesive-backed sandpaper to make up the little sanding squares. I have a couple of different grits too.

View attachment 574058 View attachment 574059

View attachment 574060

Your point about keeping the sanding right on the spirals is well taken. When I was sanding off the excess wood filler with the 320 grit sandpaper, I had to sand portions of the body tube that had no wood filler on them, just because I could not control the sanding by hand to just the area with the wood filler. I was concerned I might take off too much of the outer layer of the body tube trying to get the wood filler off. It worked out OK. The 320 grit sandpaper is still pretty fine and the stock Estes BT-60 tube is pretty thick.

 

[SolarYellow]

Only downside to sanding away from spirals is lifting fibers out of the glassine or paper. I found that the first layer of primer, using Acryli-Quik white non-sanding primer, locks all that in place so further sanding just cleans off any fibers that were raised and lets you go forward as if it never happened.

I've experimented with blocking the glassine using 400 grit before doing anything else. Knocking down the high spots on the paper while it's still super easy to sand, rather than putting primer on everything and then doing it. Will definitely be continuing to develop that approach.

 

[brockrwood]

Second coat of primer on. I let this dry and then we do the wet sand with 600 grit sandpaper.

It is crazy, but the tube spirals are still a teensy bit visible near the very bottom of the rocket. I am just going to let it go...mani padme om...mani padme om...mani padme om...

After the final sanding of primer, we will be applying the top coat - Rusoleum metallic "aluminum".

Then, once that is on, some metallic "copper" for the swoopy fins.

Then, once the paint is on, some clear coat to make the metallic finish nice and glossy.

THEN I will work on the parachute to make sure it is nice and big, has a spill hole, and the shroud lines cannot get tangled. After all of this work, I *really* don't want to lose the "1930's Diesel Punk" rocket on the first launch!

I am thinking she will launch on a C6-5 (with an adapter for the 24 mm engine mount). If not, a C11 for sure. I need to weigh it when it is all done to make sure I get the engine power right.

Going to start with wimpy motors. I hate losing rockets before I have had my fun with them.












That metallic copper can of spray paint is a little rusty on the bottom! I will need to test that on some cardboard before pointing it at Ms. Diesel Punk.

 

[fyrwrxz]

Who knew paper bird spirals would turn into "rocket science"?

 

[brockrwood]

Who knew paper bird spirals would turn into "rocket science"?

Well, in my case, I would not call it rocket science. Let’s call it rocket “tinkering”.

 

[SolarYellow]

I like to call it "rocket surgery."

I'd think a rocket that size will definitely want the C11. Build it in OR and run the numbers. I've had some OR files where the C6-7 is predicted to have a higher apogee, but is sluggish off the rod compared to the C11. Of course, neither of them touches the D12 on apogee, so go with the one that gets off the rod with more authority.

 

[Voyhager3]

I would pay a small premium to have spirals pre filled to be honest.
I’ve already wasted enough time! And I’ve only been doing this for a year or two!

 

[fyrwrxz]

I would pay a small premium to have spirals pre filled to be honest.
I’ve already wasted enough time! And I’ve only been doing this for a year or two!

Haha, I said that 57 years ago. Maybe your immune system is stronger than mine.

 

[Alan15578]

I just thought of something...

Has anyone ever tried string or floss (unwaxed) glued into the spirals?

I might try that this week.

That is the alternate approach, Don't try to hide it, embellish it. Make it look like a weld line, of add rows of rivet heads.

 

[mh9162013]

I would pay a small premium to have spirals pre filled to be honest.
I’ve already wasted enough time! And I’ve only been doing this for a year or two!

I actually enjoy filling in spirals, now. I view it as part of the building fun, like papering fins (even if they're not balsa).

 

[prfesser]

I actually enjoy filling in spirals, now. I view it as part of the building fun, like papering fins (even if they're not balsa).

"This is the Rocket Police, how can I help you?"

"There's a person in my neighborhood who is claiming that he enjoys filling spirals."

"OhMiGawd, ROCKET SWAT TEAM, prepare for deployment!! Deranged rocketeer on the loose! Almost certainly armed with multiple containers of Elmer's CWF. He is considered highly dusty and must be approached with extreme caution. Search carefully upon capture as he is probably concealing 220-grit sandpaper about his person!"

 

[mh9162013]

"This is the Rocket Police, how can I help you?"

"There's a person in my neighborhood who is claiming that he enjoys filling spirals."

"OhMiGawd, ROCKET SWAT TEAM, prepare for deployment!! Deranged rocketeer on the loose! Almost certainly armed with multiple containers of Elmer's CWF. He is considered highly dusty and must be approached with extreme caution. Search carefully upon capture as he is probably concealing 220-grit sandpaper about his person!"

For the record, I fill in spirals with sandable primer, not Elmer's CWF. This is because I'm usually building a BT-20 rocket and CWF doesn't easily fill in the very narrow spirals. I also sand the primer with 400, 600 and 1,500 grit sandpaper. 220? What am I trying to do, turn a 2x4 into a toothpick?

 

[David_Stack]

After the final sanding of primer, we will be applying the top coat - Rusoleum metallic "aluminum".

Then, once that is on, some metallic "copper" for the swoopy fins.

Then, once the paint is on, some clear coat to make the metallic finish nice and glossy.

Strongly encourage you to make up some paint sample 'swatches' and shoot those with clear first.

There are many reports where applying clear over metallic aluminium/silver paint results in the paint turning 'grey'.

 

[ep29030]

For the record, I fill in spirals with sandable primer, not Elmer's CWF. This is because I'm usually building a BT-20 rocket and CWF doesn't easily fill in the very narrow spirals. I also sand the primer with 400, 600 and 1,500 grit sandpaper. 220? What am I trying to do, turn a 2x4 into a toothpick?

THAT is dedication to the craft. Or insane. One of those two.