filling spirals

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Jozef

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Another great idea... and addresses the leveling issue
 

BABAR

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Regarding PRIMING before sanding, as opposed to CWF, I think it was @hcmbanjo that said that PRIMER before gluing was a no-no, as it is like trying to glue fins on after painting, the glue sticks to the point, no the rocket body tube. On the other hand CWF was supposedly porous, so, asssuming it wasn’t super thick, glues would adhere “through” the glue, so that was okay.

A primer exception (true for painting as well) is if you mask the adhesion sites before priming and/or painting. But if you guys have good luck with fin adhesion AFTER priming, I am probably misquoting Chris.
 

Spitfire222

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I small hobby file makes quick work of scraping off primer, CWF, and even glassine at the fin joint before gluing on the fins. Any imperfections get covered by fillets and primer/paint.
 

neil_w

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I small hobby file makes quick work of scraping off primer, CWF, and even glassine at the fin joint before gluing on the fins. Any imperfections get covered by fillets and primer/paint.
Quoted for additional emphasis.

You can either mask off the areas where the glue joints will be, or else sand off the primer there, which is very easy. Certainly, you wouldn't want to glue directly to the primer.

Filler/primer can be done after assembly as well, but it's harder to sand around the nooks and crannies, especially at LPR sizes.
 

BABAR

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I small hobby file makes quick work of scraping off primer, CWF, and even glassine at the fin joint before gluing on the fins. Any imperfections get covered by fillets and primer/paint.
Quoted for additional emphasis.

You can either mask off the areas where the glue joints will be, or else sand off the primer there, which is very easy. Certainly, you wouldn't want to glue directly to the primer.

Filler/primer can be done after assembly as well, but it's harder to sand around the nooks and crannies, especially at LPR sizes.
I sit corrected. Yes, you CAN prime the tube before attaching fins, launch lugs, or other paraphernalia, but if you haven’t previously masked the attachment areas you will need to do SOMETHING to remove that primer before you attach your parts. To my knowledge this is NOT required for CWF, although it probably wouldn’t hurt.
 

hcmbanjo

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Regarding PRIMING before sanding, as opposed to CWF, I think it was @hcmbanjo that said that PRIMER before gluing was a no-no, as it is like trying to glue fins on after painting, the glue sticks to the point, no the rocket body tube. On the other hand CWF was supposedly porous, so, asssuming it wasn’t super thick, glues would adhere “through” the glue, so that was okay.
A primer exception (true for painting as well) is if you mask the adhesion sites before priming and/or painting. But if you guys have good luck with fin adhesion AFTER priming, I am probably misquoting Chris.
I wouldn't recommend spraying filler/primer then using CWF.
Filler/primer will seal the tubes. Even if you sand the filler/primer to the tube and fin surface,
filler/primer is still left in the BT seams and wood grains. CWF applied afterwards won't stay in the seams and wood grain as well.

CWF is water based and water based wood glues will permeate it.
Filler/primer seals tubes, wood glued balsa and card stock won't stick as well.
Use CWF first, sand to surface, then spray the filler/primer and sand.

In the first picture below you can see some CWF left in the tube seams after sanding.
Before spraying the body tube with filler/primer I mask off the fin gluing line with a strip of masking tape.
The tape strip is a hair wider than the fin for better adhesion of the glue fillet later.
The fins in the left side picture hasn't had the filler/primer sanded down yet.

The second picture shows the root edge fillet area sanded down (a little more filler/primer removed)
for better glue fillet adhesion.
 

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Mx2

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Kind of new to all of this and I hope these pictures work. Taking others ideas this is how I do my spirals:

A. Mark all spirals to be filled with marker.
Using 120 grit, spin tube and lightly rough up surface, Usually a soft pass up and back To remove waxy covering. (see step C.)

B. Using ??-putty from Hobby Lobby. Dip finger in alcohol if needed, cover spirals “thinly“. If it makes little clumps don’t worry, don’t overwork putty. Set aside to dry in sun about 5 minutes, while shaking primer and get cordless drill.

C. I use dowels with tape to adapt the tube to drill & spin tube during process.

I start very lightly with 120 grit. 1 soft pass up and back with slow spin to remove chunks. Then green scratchy pad, a quick spin on 200 grit, 400 grit, then fine steel wool at a higher speed.
if needed touch up areas with putty, spinning smooth after. You will notice the spinning sanding creates heat, heat creates quicker drying of the putty. Give it five minutes and then spray primer.

While spinning rocket tube with drill spray primer. Wait 5 minutes or so. Use 400 grit, smooth, then steel wool.
Repeat as needed.
The process isn’t perfect but tube is done quickly. From start to finish, about 40 min. depending on outside temps.

spin when painting too! (as always light coats of paint)
E7C0104D-E42B-462D-A81D-7311C84CA614.jpeg12A4C042-50A9-41CE-8135-4D0C193B3F54.jpegA49CF2D0-D015-40D4-9E2E-46CA158B982C.jpeg480CF901-F278-44D6-92C8-1EACD5D36C2A.jpeg62C0C688-BFA1-4546-A6EE-A1412284DD45.jpeg2B9770E8-6414-4EE4-A1B5-29AF2AA42FA8.jpegBA637106-5978-40C7-B0D1-8CAB776D4EB2.jpeg9614D57C-B45F-457A-B954-01861BE9E343.jpeg
 

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Bill S

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Well I have to say I never thought of using a method like that. Interesting idea.

I have to wonder if the greyness of the tube is due to the grey putty, or tiny particles of the steel wool embedding themselves in the tube? If the steel wool, would that affect the finish in time, due to the steel particles oxidizing?
 
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Greg Furtman

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Kind of new to all of this and I hope these pictures work. Taking others ideas this is how I do my spirals:

A. Mark all spirals to be filled.
Using 120 grit, spin tube and lightly rough up surface.

B. Using ??-putty from Hobby Lobby. Dip finger in alcohol if needed, cover spirals “thinly“. If it makes little clumps don’t worry, don’t overwork putty. Set aside to dry in sun about 5 minutes, while shaking primer and get cordless drill.

C. I use dowels with tape to adapt the tube to drill & spin tube during process.

I start very lightly with 120 grit. 1 soft pass up and back with slow spin to remove chunks. Then green scratchy pad, a quick spin on 200 grit, 400 grit, then fine steel wool at a higher speed.
if needed touch up areas with putty, spinning smooth after. You will notice the spinning sanding creates heat, heat creates quicker drying of the putty. Give it five minutes and then spray primer.

While spinning rocket tube with drill spray primer. Wait 5 minutes or so. Use 400 grit, smooth, then steel wool.
Repeat as needed.
The process isn’t perfect but tube is done quickly. From start to finish, about 40 min. depending on outside temps.

spin when painting too!
View attachment 423018View attachment 423010View attachment 423011View attachment 423012View attachment 423013View attachment 423014View attachment 423015View attachment 423016
Now that is an interesting way to fill & sand. I'm going to have to give that a try. :)
 

Jozef

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I wouldn't recommend spraying filler/primer then using CWF.

In the first picture below you can see some CWF left in the tube seams after sanding.
Before spraying the body tube with filler/primer I mask off the fin gluing line with a strip of masking tape.
The tape strip is a hair wider than the fin for better adhesion of the glue fillet later.
The fins in the left side picture hasn't had the filler/primer sanded down yet.

The second picture shows the root edge fillet area sanded down (a little more filler/primer removed)
for better glue fillet adhesion.
X2
 

JLP1

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So this will be my first time using the Bondo spot putty to fill the spirals. I had a piece of LOC BT to practice on, first I used the low tack blue tape on both sides of the spiral then I applied the putty using an old credit card. You can see the difference in the spirals the one above has no putty and the one below has a nice clean line of putty after the tape is removed.

1593789758185.png


So after the putty dried I started sanding off the excess you can see were the putty remained in the spiral. Am I on the right track with this or should I do it differently?

1593790653257.png


Thanks Everybody
 
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neil_w

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Looks good, my only comment would be: masking every spiral is a *lot* of work. I don't think it's necessary, and AFAIK most folks don't do this.
 

Mx2

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Well I have to say I never thought of using a method like that. Interesting idea.

I have to wonder if the greyness of the tube is due to the grey putty, or tiny particles of the steel wool embedding themselves in the tube? If the steel wool, would that affect the finish in time, due to the steel particles oxidizing?
In the photos I try to show the various stages. The spiral is of course the putty being smoothed and then I primed it and smooth again as needed etc., If it‘s to blotchy spin and sand with 400 grit. Just takes a moment to take it back to cardboard. If it looks mostly good on one end that’s the nose and the roughest end be the fins.

yes, I believe the steel wool may be creating some darker areas In the primer coat, possibly by Heat that is created and or stain impregnated into primer which thus far hasn’t seemed to effect painting.
My Desire is not to obtain a perfect paint job for a showpiece. What I seek is to launch eye appealing rockets from 10 ft away or whatever. It took me a couple to get it right but I can actually prime a Single Estes rocket body tube in < half hour. (But as earlier discussed When attaching fins or launch lugs, you have to scratch away the primer to allow adhesion back to the cardboard.). It works and not that complicated.
 
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Mx2

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. Ooops, can’t figure out how to delete this errant reply.
*cue elevator music here.
 
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Greg Furtman

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In the photos I try to show the various stages. The spiral is of course the putty being smoothed and then I primed it and smooth again as needed etc., If it‘s to blotchy spin and sand with 400 grit. Just takes a moment to take it back to cardboard. If it looks mostly good on one end that’s the nose and the roughest end be the fins.

yes, I believe the steel wool may be creating some darker areas In the primer coat, possibly by Heat that is created and or stain impregnated into primer which thus far hasn’t seemed to effect painting.
My Desire is not to obtain a perfect paint job for a showpiece. What I seek is to launch eye appealing rockets from 10 ft away or whatever. It took me a couple to get it right but I can actually prime a Single rocket body tube in < half hour. (But as earlier discussed When attaching fins or launch lugs, you have to scratch away the primer to allow adhesion back to the cardboard.). It works and not that complicated.
@Mx2 You could try fine ScotchBrite pads instead of steel wool. They don't shed like steel wool does. The maroon pads are about 320 grit and they do make them finer.
 
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hcmbanjo

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Just some more questions that I don't see discussed as often. What are the tools and techniques that you use for application of whatever filler, be it bondo or spot putty or CWF? I think the primer method is pretty self explanatory, but in that case I wonder how you avoid raising fibers from the substrate while sanding.

The advantage to this method is the filler is directed into the seam with the CWF on the knife blade.
Best to use an older blade.
The CWF coverage area ends up narrow, a little wider than the seam being filled.
Like any new technique, it takes a little practice.

CWF filler first and sand. Then follow with filler primer and sand.
Two steps and the seams are filled.
 

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Greg Furtman

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The advantage to this method is the filler is directed into the seam with the CWF on the knife blade.
Best to use an older blade.
The CWF coverage area ends up narrow, a little wider than the seam being filled.
Like any new technique, it takes a little practice.

CWF filler first and sand. Then follow with filler primer and sand.
Two steps and the seams are filled.
Great tip! Thanks, I'll have to give it a try.
 

Off Grid Gecko

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While it can bring it's own set of issues, I am getting to the point where if I really want my spirals filled perfectly, I'll build a fiberglass kit. 🤣
That's a sound solution. I just finished spraying my new LPR and I got to a point where I said "that's all the primer I'm willing to use on a low power rocket." On to paint. It's mostly smooth but there are still a couple of unsightly bits of spiral here or there.
 

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That's a sound solution. I just finished spraying my new LPR and I got to a point where I said "that's all the primer I'm willing to use on a low power rocket." On to paint. It's mostly smooth but there are still a couple of unsightly bits of spiral here or there.
Mach 1 has made it nice for LPR in that regard...
 

jrap330

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Kind of new to all of this and I hope these pictures work. Taking others ideas this is how I do my spirals:

A. Mark all spirals to be filled with marker.
Using 120 grit, spin tube and lightly rough up surface, Usually a soft pass up and back To remove waxy covering. (see step C.)

B. Using ??-putty from Hobby Lobby. Dip finger in alcohol if needed, cover spirals “thinly“. If it makes little clumps don’t worry, don’t overwork putty. Set aside to dry in sun about 5 minutes, while shaking primer and get cordless drill.

C. I use dowels with tape to adapt the tube to drill & spin tube during process.

I start very lightly with 120 grit. 1 soft pass up and back with slow spin to remove chunks. Then green scratchy pad, a quick spin on 200 grit, 400 grit, then fine steel wool at a higher speed.
if needed touch up areas with putty, spinning smooth after. You will notice the spinning sanding creates heat, heat creates quicker drying of the putty. Give it five minutes and then spray primer.

While spinning rocket tube with drill spray primer. Wait 5 minutes or so. Use 400 grit, smooth, then steel wool.
Repeat as needed.
The process isn’t perfect but tube is done quickly. From start to finish, about 40 min. depending on outside temps.

spin when painting too! (as always light coats of paint)
View attachment 423018View attachment 423010View attachment 423011View attachment 423012View attachment 423013View attachment 423014View attachment 423015View attachment 423016
Please expand how you use dowels to fit body tube to drill...did you buy a dowel that is exactly the size as tube or do you "beef it " up until tube frictions fits on dowel ?
 

o1d_dude

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That's a sound solution. I just finished spraying my new LPR and I got to a point where I said "that's all the primer I'm willing to use on a low power rocket." On to paint. It's mostly smooth but there are still a couple of unsightly bits of spiral here or there.
i cannot see unfilled spirals from the range head while the rocket sits on the pad.

No one else can either.

To be honest I will touch up paint chips with Sharpie markers but that’s pretty much all I’m willing to to do.
 

Mx2

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Beef
Please expand how you use dowels to fit body tube to drill...did you buy a dowel that is exactly the size as tube or do you "beef it " up until tube frictions fits on dowel ?
I beefed up the dowel to make it snug against inside of rocket body. Doesn’t have to be tight. Snug works. Go from there.
To connect to drill I just found center of dowel drilled into it with a drill and left it in there.
 
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Off Grid Gecko

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i cannot see unfilled spirals from the range head while the rocket sits on the pad.

No one else can either.

To be honest I will touch up paint chips with Sharpie markers but that’s pretty much all I’m willing to to do.
Training myself to take some more time rather than slapping something together in the morning and launching it that afternoon. My dad used to do body work, and cited the 20/20 rule often. If a car is moving 20mph 20ft away and the defect isn't noticed, then it isn't a defect.
 

o1d_dude

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Training myself to take some more time rather than slapping something together in the morning and launching it that afternoon. My dad used to do body work, and cited the 20/20 rule often. If a car is moving 20mph 20ft away and the defect isn't noticed, then it isn't a defect.
Agreed.

My rockets may not have filled spirals but the internals and construction are as good as I know how to make them.
 

hcmbanjo

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Kind of new to all of this and I hope these pictures work. Taking others ideas this is how I do my spirals:

A. Mark all spirals to be filled with marker.
View attachment 423010

You mentioned you are new to this -
I'd shy away from using a marker (or pen) to mark your spirals.
Inks can bleed through your finish paint. You'll have better end results with a pencil.
120 grit is pretty aggressive for a paper or Kraft tube.
Start with 220 and move to 400 grit.
 

Mx2

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View attachment 423010

You mentioned you are new to this -
I'd shy away from using a marker (or pen) to mark your spirals.
Inks can bleed through your finish paint. You'll have better end results with a pencil.
120 grit is pretty aggressive for a paper or Kraft tube.
Start with 220 and move to 400 grit.
Input appreciated, clarification adjustments added:
“New to this“ is actively submitting ideas as past scripts to any group become overtly condemned so I simply do my thing. The process is sound to the individuals dissection of given idea.

sharpy pen has yet to bleed through and yes pencil could be used but ink is better as it keeps ones eyes focused on area of putty application. (Thin and over line)

yes, agree 120 grit is very aggressive. Very soft pressure, one pass up and back but agree, 220 or 300 for first pass is fine. Good eye on that. I questioned myself about putting that in there but on some tubes that have waxier coating it removes quickly. Any damage to the tube (fraying) is quickly locked down with primer and smoothed by steel wool. I can start with 120 if I’ve made a mess with the putty. 220, 300 works, even 400. Like most process’s it becomes an individual skill. Although belated, I will attempt to change that to 220 grit.

I can use 400 grit and steel wool for the entire process depending on how clean putty was applied, pressure of my hand during sanding and speed of rotation.

A clean application of putty and smooth tube in experienced hands is quickly completed. So the earlier prattling of others as being to time consuming I can only scratch my head as possibly they can do it faster then I by utilizing their years of modeling experiences.

Like most posted items it’s an idea. A process; a process that I use.

A person could glean what they feel useful, or not.
 

Wally Ferrer

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I put the filler on thinned quite a bit, and use an old card to scrape most of it off to minimize how wet it might make the tube as well as the sanding.


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