Die! Spirals Die!

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buzz

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What do you have to do to get rid of these spirals man.
I've filled the bt spirals with spakling paste, sanded it smooth,
ten coats of grey primer, sanding in between coats, but I can still
see them!


I thought about spraying the bt with adhesive and covering it with paper, but then I guess I,d have a seem down one side.
of the tube.









:mad: :mad: :mad: :( :mad:
 

vjp

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Are you using a sanding block? If you use sandpaper with your fingers, the sandpaper tends to sink into the grooves and remove the filler from them. By using a flat block, the sandpaper doesn't dig out the filler from the grooves as much.
 

DynaSoar

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Originally posted by buzz
What do you have to do to get rid of these spirals man.
I've filled the bt spirals with spakling paste, sanded it smooth,
ten coats of grey primer, sanding in between coats, but I can still
see them!

I thought about spraying the bt with adhesive and covering it with paper, but then I guess I,d have a seem down one side.
of the tube.

First rub the spackle into the cracks with your finger, rubbing fore and aft to work it in. Then rub spackle all over the entire tube. I use a rubber glove for this. It's enormous fun. When you sand, use a large piece of sand paper wrapped around the tube. This will make a lot of dust, and it's an irritant, so use a mask and do it outside if possible.

I'm about to do exactly what you suggest with some paper. Actually it's self adhesive vinyl shelf/drawer liner. I'm going to spray the underside of it as I wrap it on the tube. But I filled the spirals with spackle first.

I've also had good luck filling small spirals with satin finish Rustoleum between the primer and top coats, and with appliance epoxy Rustoleum as a top coat.
 

GlennW

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Here is another idea I saw on EMRR about this. You can simply spray a heavy coat of primer on the BT holding the can close. Then sand down to the surface and the primer will remain in the grooves, filling them. Last, prime over and paint. Btw, this appeared in the review of the Apogee Saturn 1B and/or the Saturn V.

Glenn
 

polaris

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I have had good luck with two techniques:
• Sanding blocks
• Using a long strip of sandpaper to “buff” the tube.

I think they work because you don’t dip down into the spiral as much as you do using your fingers to support the sandpaper.

I have also had luck with the brown Krylon primer and no spackling. I only sprayed the spirals, then sanded. I repeated a couple of times. When the spirals are filled, I sprayed the whole BT and sanded. Once again it worked better when I didn’t use my fingers to support the sandpaper.
 

Micromeister

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Buzz:
I've haven't used any type of filler in over 6 years. micro to Large BT-80 size model body tubes and Balsa or Basswood fins are spray primer filled using this method.
Three wet coats of primer are applied to the entire model.
Sand with 120grit paper on a sanding block until I see tube and/or wood.
a second application of 3 wet coats of grey or black primer are applied.
Sand with 220 - 240 paper until no seam or grain are visible.
2 coats of White Primer are applied and sanded to a baby smooth finish with 320, 400 and 600grit papers.
apply you base color coat. wet sand any slight imperfection found it the gloss application.
Finish paint to taste with colors of your choice:D
 

wscarvie

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Hi Micro,

OK, great process. I get it.

But, do you smooth your tubes before, or after you attach the fins?

If before, what do you do, if anything, to make the joints between fins and tubes strong enough?

Thanks much!
 

GlassfibreMan

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Why bother with all that filling and sanding? I always use Solarfilm as used by aeromodellers. It's light weight, easy to apply to a body tube and it only takes minutes. I have never understood why more rocketeers don't use it. OK it may be a bit iffy for HPR but for LPR and MPR I have never had any problems.
 

BobH48

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Originally posted by GlassfibreMan
Why bother with all that filling and sanding? I always use Solarfilm as used by aeromodellers. It's light weight, easy to apply to a body tube and it only takes minutes. I have never understood why more rocketeers don't use it. OK it may be a bit iffy for HPR but for LPR and MPR I have never had any problems.
Do you use the iron-on stuff or the self-stick trim film?

I never even gave it a thought.

I have rolls of Monokote, Solarfilm, Coverite, etc. left over from my R/C days.
 

GlassfibreMan

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Always iron on. It's very forgiving and if you just iron on say 1/4" down the length you can line it up, wrap it around and then iron the rest on.
 

BobH48

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Thanks for the tip on the Solarfilm. I think I'll try it out.
 

jflis

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Originally posted by GlassfibreMan
Why bother with all that filling and sanding? I always use Solarfilm as used by aeromodellers. It's light weight, easy to apply to a body tube and it only takes minutes. I have never understood why more rocketeers don't use it. OK it may be a bit iffy for HPR but for LPR and MPR I have never had any problems.
why bother with all that filling sanding, and cutting and ironing?

Heck, from the LCO table, I can't see a *SINGLE* spiral, no matter *how* hard I look....

:D :D
 

BobH48

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Originally posted by jflis
why bother with all that filling sanding, and cutting and ironing?

Heck, from the LCO table, I can't see a *SINGLE* spiral, no matter *how* hard I look....

:D :D
I am assuming that if I use the Solarfilm in the colors that I want, I won't have to paint . :D

That alone is worth it. :p

PS. I don't normally bother filling spirals anyway. ;)
 

wscarvie

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OK, this is something of a reprise of my last question, but tuned to the Solarfilm vibe:

Do you cover your tubes and fins before, or after assembly? If after, any tips for getting the film trimmed just right at the fin/tube joint?

If before, any tips on prepping the joint area on the tube? Do you cut/sand away the Solarfilm before gluing?

Thanks,

Will
 

GlassfibreMan

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Do you cover your tubes and fins before, or after assembly? If after, any tips for getting the film trimmed just right at the fin/tube joint?
I always make up a seperate fin can, usually frp (see my frp site) or body tube and couplers if going for lightweight. The reason I do this is so I can have more options on fin shape or engines. For my Metamorphis X2 I currently have 2 fincans, one to take upto 38mm and the other a two cluster 24mm. See my personal site

So the answer is I only cover the body tube with solarfilm. As for how is it trimmed; as I said, I iron down one edge strip, wrap the film around, overlapping the edge strip, iron it all on. To trim I cut down the overlapped area with a straight edge and sharp blade. The two overlapped pieces can then be peeled off leaving a clean join. One piece will be under the other so it's a case of unsticking, pulling it out and then sticking the edge with an adhesive. Don't use heat because it will shrink further and leave a gap between the two edges.It's easier than it sounds.
 

KermieD

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Saw a guy use holographic wrapping paper and 3M spray adhesive. It actually looked really great!!!
 

Stymye

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this happens alot judging from how many times I've read it on here

I've had the same thing happen more than a few times and it took a while to figure out ,, I fill and sand the spiral , spray primer and the spiral is magically still there.

thts because on most glassine tubes there are 2 sets of spirals, did you fill them both?

one set is obvious, the one created by the edges of the glassine wrap , than the second spiral is under the glassine layer created by the paper wrap itself. the glassine tends to sink into this second spiral and can fool you into thinking you didn't do a good job,,because it's not very obvious when the tube is bare


now I just fill both spirals you should have two seperate runs of filler going around the tube

I'm willing to bet this is what happened if it was a glassine tube.
 

jpasqual

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I think this process will explain how to get rid of that second spiral we all hope to eliminate in the prep work - hope this helps

Filling BT Spirals
 

Stymye

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also the wrapping idea is a good one but limited
sure you can just wrap the pesky tube on your sport rocket and avoid the problem in most cases ... but try building a scale rocket or missile that has 5 different colors and and numerous details to attach. it would drive you nuts.
 

buzz

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You guys are doing it! Your killing the spirals!

Thanks everybody. TRF:kill: SPIRALS
 

JRThro

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Originally posted by jflis
why bother with all that filling sanding, and cutting and ironing?

Heck, from the LCO table, I can't see a *SINGLE* spiral, no matter *how* hard I look....

:D :D
Then my rockets would look fine to you, even though 80% of them are bare white tubes with bare wood fins!

Cool!
 
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