# filling spirals

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#### o1d_dude

##### 'I battle gravity'
Wondering if something like this could be used to spin tubes for filling:

Amazon. It’s called a cup turner.

I swear....sometimes I think the internet reads my posts and my mind...

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#### neil_w

##### Brain and brain, what is brain!?!
TRF Supporter
At only 2.5 RPM my guess is that is not what you want. Could be the basis of a decent rotisserie unit though.

#### Mx2

##### Member
At only 2.5 RPM my guess is that is not what you want...
Yes, faster speed but you did go a route I haven’t thought of and that is seeing what is all ready on market.

I was thinking about what you said regarding 3” and 4 inch and what one could do quickly, cheaply. No great flashes of inspiration on this end although I was thinking about it.

Currently I have about three Estes rocket kits I still need to build (small tube) and no immediate plans for larger tube. But all it would take is a device like you had found, possibly like a shoe buffer? Ahhhh, maybe? Laying in the back of a Thrift store for about $10 that could be easily converted over.... so I like your thinking what is out there that could turn 3 or 4 inch cardboard tube with minimal re-work and not creating a hazard to fingers and limbs. Hmmmmm... #### Mx2 ##### Member Wondering if something like this could be used to spin tubes... I responded to your post but under the guy below you, Neil W, Interesting but I think low RPMs there’s an issue. #### o1d_dude ##### 'I battle gravity' Yes, faster speed but you did go a route I haven’t thought of and that is seeing what is all ready on market. I was thinking about what you said regarding 3” and 4 inch and what one could do quickly, cheaply. No great flashes of inspiration on this end although I was thinking about it. Currently I have about three Estes rocket kits I still need to build (small tube) and no immediate plans for larger tube. But all it would take is a device like you had found, possibly like a shoe buffer? Ahhhh, maybe? Laying in the back of a Thrift store for about$10 that could be easily converted over.... so I like your thinking what is out there that could turn 3 or 4 inch cardboard tube with minimal re-work and not creating a hazard to fingers and limbs.
Hmmmmm...
Great idea!

A shoe buffer would an excellent place to start.

#### jrap330

##### Retired Engineer, NAR # 76940
TRF Supporter
Wondering if something like this could be used to spin tubes for filling:

Amazon. It’s called a cup turner.

I swear....sometimes I think the internet reads my posts and my mind...
It is design for cups and mugs....so 3-4 inch diameter????/Video..turns slow....so there goes you saving time by fast spin...sand etc

#### o1d_dude

##### 'I battle gravity'
It is design for cups and mugs....so 3-4 inch diameter????/Video..turns slow....so there goes you saving time by fast spin...sand etc
I’d imagine the motor could be replaced easily enough to address the slow speed issue but at this point I’m thinking about @Mx2 ‘s idea of using a shoe buffer...

#### jrap330

##### Retired Engineer, NAR # 76940
TRF Supporter
Back to using drill..issue was beefing up a wooden dowel to hold air frame. If you installed the motor mount...then just glue an engine casing to a dowel and spin. .I do not think shoe buffer/shiner spin fast either..

#### neil_w

##### Brain and brain, what is brain!?!
TRF Supporter
I do not think shoe buffer/shiner spin fast either..
Yeah they do. I remember my dad had one way back when.

#### Mx2

##### Member
Back to using drill.....
For now.... my spider senses are tingling.... hmmmm.....

#### BABAR

##### Builds Rockets for NASA
TRF Supporter
If you spin too fast won’t it fling the paint right off?

#### Mx2

##### Member
Possibly. Variable speed control, slow down rpm or quantity of paint.

#### Zbench

##### Well-Known Member
TRF Supporter
Mx2, I have to hand it to you on that Tamiya Basic Putty. I picked some up after looking at you using it on the video. I discovered that if you just get a little ball on your index finger you can move about 6" around a spiral before you have to reload. If you press and spread it thin it goes even farther.

I am working on an Aspire build and treated the upper half that way, doing both spirals, the deep one and the shallow one. It hardened up in about 20 minutes. I just used a pad of steel wool and worked it in my hand and then sprayed with my Seymour Filling primer. It worked fantastic. One coat and smoothed it out again with the 0000 steel wool and I am done.

That Tamiya putty is pretty tenacious and dries hard. I like that if flows smooth unlike bondo that gets clumpy really fast. It's a great solution. Thanks for the tip.

#### RocketTree

##### Well-Known Member
I mask the spiral above and below with tape. Brush filler primer into the spiral 2-3 coats. Remove tape. Sand down and prime the whole rocket tube. Spirals gone!

If you use automotive filler, get "glazing putty". Bondo body filler is too "hard" to sand on a paper body tube.

All the best!

#### brockrwood

##### Well-Known Member
TRF Supporter
If you have a piece of scrap tubing, I suggest trying it that way and see if you like it.
But if I use my “scrap” tube I won’t have it for my next kit bash!

#### Mike Haberer

##### DaHabes
TRF Supporter
On my latest build I've used Bondo thinned with acetone. I make it as runny as possible and apply with a quality paint brush. The main problem with Bondo is the volatiles evaporate so quickly it is hard to spread evenly without clumping. Thinning helps. Once applied I go over any clumpy spots with the brush dipped in acetone, which helps spread the lumps out. I haven't gotten to priming yet, but the sanded airframe looks good.

#### neil_w

##### Brain and brain, what is brain!?!
TRF Supporter
But if I use my “scrap” tube I won’t have it for my next kit bash!
Nonsense; it just means that tube will be “ready to go” for your next build.

BTW dunno if I mentioned this before but I’ve started lightly sanding the whole tube with 400 grit before applying the CWF to help it adhere better (vs. the raw glassine).

#### brockrwood

##### Well-Known Member
TRF Supporter
Nonsense; it just means that tube will be “ready to go” for your next build.

BTW dunno if I mentioned this before but I’ve started lightly sanding the whole tube with 400 grit before applying the CWF to help it adhere better (vs. the raw glassine).
The tube manufacturers should just omit the glassine finish.

#### ep29030

##### Mark N.
TRF Supporter
I found the sandpaper doesn't load as quickly if I sand sometimes in an orbital or circular motion.

#### Greg Furtman

##### Well-Known Member
TRF Supporter
I found the sandpaper doesn't load as quickly if I sand sometimes in an orbital or circular motion.
Try some Mirka Abranet. Great stuff. Open mesh and when it fills up (which takes a lonnnggg time) just blow air through it from the backside and it is unloaded.

#### Mike Haberer

##### DaHabes
TRF Supporter
The tube manufacturers should just omit the glassine finish.
I agree. I usually sand down the entire tube before filling spirals. You want adhesion - of filler of choice, primer and paint. Glassine isn't good for adhesion, period.

#### Back_at_it

##### Well-Known Member
I always do the filling after assembly. I don’t want any material getting between the glue bond on the fins.

Depending on the depth of the grooves I will either use DAP brand wood filler for the deeper stuff or simply use SEM high build automotive primer. For grooves in typical Estes kids, two coats of SEM primer will typically fill them completely without the need for wood filler.

SEM also sans very easily and doesn’t clog the paper. I also wet sand everything so this really has never been an issue regardless of the brand

##### Lonewolf.... No Club
TRF Supporter
They are external rifling... embrace them.

#### kuririn

##### BARGeezer
TRF Supporter
Lately I've been using this Aussie product I got from Amazon called Timber Mate. It's a water soluble wood filler with the consistency of putty. Just put a gob on your fingertip and run it along the spirals, going perpendicular to get it into the trough.
Just did a Squared Max tube, took maybe 5 minutes.

Also used it on the New Way Flat Boy with good results

Next: gonna try it on a foam Spaceship One. Tamiya white putty has a solvent that eats foam.

Laters.

#### ep29030

##### Mark N.
TRF Supporter
I found the sandpaper doesn't load as quickly if I sand sometimes in an orbital or circular motion.
You can use a large gum eraser--yes, the kind you used in elementary school--to unload sandpaper. Use it all the time on belt sanders, and it works on small pieces of sandpaper equally well.

#### aviserated

##### Well-Known Member
Testors makes a putty that comes in a Gray tube. The tube is shaped much like their plastic cement tubes. Hobby lobby sells it. Smells alot like lacguer putty and should be more easy to apply than the red Bondo stuff.

#### DES

##### Well-Known Member
The Bondo #907 solvent based glazing putty works really well. This is a solvent based putty very similar to the Testors or Tamiya, just a little bit thicker. Not the "Professional Glazing Putty" which is a two part polyester.

I have had really good luck with the "smear and wipe" technique. It is fast, and very little sanding required. Basically you smear a thin film of the solvent based glazing putty over the body tube, let it start to dry a bit so it gets thicker, then quickly wipe it all off with a paper towel, scrubbing across the spirals. It leaves the filler in the groves, but very little on the surface of the tube. The putty dries fast, so you have to do a section at a time and not get carried away. You can repeat the process a couple of times if the grooves are deep, or you can apply the putty directly to the groove, and use a plastic scraper to level it off. It goes really fast.

Then you sand and prime. Two coats of a fast dry lacquer base primer, with sanding between usually fills all the spirals. This will depend on your body tube and how deep the groove are. I don't like "spray fillers". They are soft and gummy, don't sand well, and don't really seem to fill spirals well.

#### aviserated

##### Well-Known Member
Wouldn't it be best to spray on primer first then next apply the putty?

#### NateB

##### Well-Known Member
Wouldn't it be best to spray on primer first then next apply the putty?
That's what I do. I prime and sand, which helps find the low spots. Use Bondo spot putty, sand, prime, sand and repeat until I'm happy.

#### brockrwood

##### Well-Known Member
TRF Supporter
One of those pics definitely looks like a still pic from CSI.