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Filler for spiral tubes?

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Jeff278

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Just wondering what most use to fill in the grove of a spiral tub? I have used green model putty and sheet rock putty with good results, what do you use ?

Thanks Jeff
 

AfterBurners

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Apogee had a video where Tim was using epoxy clay to fill the grooves on a blue tube. Turned out pretty nice. He would just mash it into the spiral and scrap the excess off with a razor blade.
 

neil_w

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I think the most common, at least for paper tubes, is thinned Elmers Carpenter's Wood Filler (aka CWF or FNF). That's what I use.

There are plenty of other options though.
 
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AfterBurners

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I think the most common, at least for paper tubes, is thinned Elmers Carpenter's Woof Filler (aka CWF or FNF). That's what I use.

There are plenty of other options though.
That seems to be the preferred choice by most.
 

fyrwrxz

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So many punch lines, I'll just let the mental movies play out......
+1 on the woof plug......
 

Jeff278

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The Woof filler Works great, and easy clean up. THANKS!
 

DinoAP

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Woof filler is great, doesn't leave a Ruff surface.
 

Sooner Boomer

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I think a lot has to do with the type of tub...or tube. For paper, FNF seems to work fine, unless it's really porous and sucks all the water out. In these cases, you need to prime or seal the surface first. For phenolic tubes, I've used Bondo spot putty with great results, if you can stand the smell.

Again, pointing out the obvious, solvent-curing putties/fillers dry from the outside, in. If you slather too much on, it will crack. Catalyzed compounds (like epoxy) cure throughout at the same rate. Unless there is heat generated by the curing, you can generally put on as much as you want at one go.
 

Rktman

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Agree with sooner.boomer that it depends on the type of tube. The smaller diameter body tubes I use tend to have very shallow spiral grooves so the Elmer's Carpenter's Wood Filler mentioned by neil_w and Mr Rocket works fine. Bigger HPR tubes with deeper grooves seem to do better using epoxy putty.
Another tip I picked up elsewhere in the Forum is to coat your bt with sanding sealer afterwards to smooth down the rough surface you get from sanding down the CWF. It not only strenthens the tube but gets it glassy smooth while filling in any tiny areas in the spiral that the CWF might have missed.

 

Mr Rocket

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Another tip I picked up elsewhere in the Forum is to coat your bt with sanding sealer afterwards to smooth down the rough surface you get from sanding down the CWF.

+1 on the sanding sealer. This works really great when using rough mailing tubes or paper spools.
 

BABAR

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Another tip I picked up elsewhere in the Forum is to coat your bt with sanding sealer afterwards to smooth down the rough surface you get from sanding down the CWF. It not only strenthens the tube but gets it glassy smooth while filling in any tiny areas in the spiral that the CWF might have missed.

Sounds great. NOT sure if this may be an issue if done before fin or launch lug placement.

Elmer's Wood Filler is okay to go on underneath fins and lugs as it is porous, so glues will go right through it for good adhesion.

I know that PRIMER (as well as paint) is a NO NO before fin or lug placement.

I am NOT sure about sanding sealer, particularly given there are different types. Something about "glass smooth surface" and "fin adhesion" sounds like a problem.

Maybe the more experienced with sanding sealer can chime in here.
 

rharshberger

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Sounds great. NOT sure if this may be an issue if done before fin or launch lug placement.

Elmer's Wood Filler is okay to go on underneath fins and lugs as it is porous, so glues will go right through it for good adhesion.

I know that PRIMER (as well as paint) is a NO NO before fin or lug placement.

I am NOT sure about sanding sealer, particularly given there are different types. Something about "glass smooth surface" and "fin adhesion" sounds like a problem.

Maybe the more experienced with sanding sealer can chime in here.
Sanding sealers are usually a lacquer, shellac, poly, or butyrate dope which have additives to assist smoothing all of which are non-permeable.
 

Rktman

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Sounds great. NOT sure if this may be an issue if done before fin or launch lug placement.

Elmer's Wood Filler is okay to go on underneath fins and lugs as it is porous, so glues will go right through it for good adhesion.

I know that PRIMER (as well as paint) is a NO NO before fin or lug placement.

I am NOT sure about sanding sealer, particularly given there are different types. Something about "glass smooth surface" and "fin adhesion" sounds like a problem.

Maybe the more experienced with sanding sealer can chime in here.[/QUOTE

I should have been more specific and noted that the sealer goes on after fins and lugs. Or I sand it off in the attachment area if it's a complicated fin design that makes applying and sanding the sealer in tight areas difficult or impossible.
 

BABAR

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Sanding sealers are usually a lacquer, shellac, poly, or butyrate dope which have additives to assist smoothing all of which are non-permeable.
thanks!
 
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