Elmer's Carpenter's Wood Filler

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Scode68

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So, I figured I would try to use this on the fins of a new rocket but have a few questions.

  1. Do I seal the wood with a sealer first?
  2. Do I need to use a sealer after I use the filler?
  3. How long should I wait till I sand?

Package says I can sand in 15 minutes but that is for shallow repairs right out of the tube. I thinned it and painted it on.
 
Okay, I'll give my 2 cents. But be ready, everyone has their best methods on using Carpenter's Wood Filler. (That's the new name for Elmer's Fill N' Finish.)

1. You won't have to seal the balsa using this filler.
2. You don't have to use sealer after using the filler.
3. Because you've added water to the mix, it'll take longer to dry than the recommended 15 minutes. I usually wait a few hours before sanding it. On flat surfaces, I use 400 grit on a sanding block. Some may think this is too fine a grit. The great thing is, it won't load up on your sandpaper like the old sanding sealer did.
Ideally you want to leave a very thin coating of the filler overall on the balsa. If you see some balsa peeking through the sanded filler, you gone too far. I tend to do two coats of the filler.

When I got back into rocketry, it took a few tries to get the water/filler mix right. You should be able to brush it on easily. Use the 1" wide cheap utility brushes you'll find at Home Depot or Lowe's.

Some say the Stainable Carpenter's Wood Filler sands easier. I just got some today, I'll let you know how it works later.
 
To echo hcmbanjo's remarks.....

I use it all the time, but first I thin it down with a little bit of water to about the consistancy of paste or pancake batter. I use it to fill fins and nose cones, fill body tube spirals and to make fillets.

So to answer your questions, here are my observations/experiences:
1. I don't seal mine first, but you could if you wanted. I don't think it is neccessarry though, and my opinion is that it adds extra work. I think the wood filler is accomplishing the same thing that the sealer does.
2. No you don't, although (again) you could if you wanted to, but it isn't needed. I don't do it.
3. It depends on how thick you put it on and how much water you use when you thin it down, but my experience is that I usually let it dry about an hour. If it is still a little wet, it won't sand well.

A couple tips from my experiences:
A. Place a small amount of filler in a small disposable cup or jar for thinning, and add water very sparingly - a little goes a long way.
B. If you use it to seal balsa fins, do both sides of the fin at the same time to prevent warping.
C. Shortly after you apply it, you can dip your finger in water then rub it over the filler to help smooth it out. The smoother it goes on, the less sanding you will need to do later.

For me, I live in an apartment with less-than-optimal ventilation, so sanding sealer always stunk up the place and gave me a headache. That problem completely went away for me when I replaced sanding sealer with wood filler. No fumes and easy soap and water clean up.

Here are some fillets on a Big Daddy that I used watered-down wood filler for:

Big Daddy Fillet.jpg
 
Yeah, what Hans said.

Dry time dependent on final consistency after adding water. I shoot for yogurt consistency (the real stuff, not the semi-solid stuff) and it dries in a couple of hours.
 
I just sanded it and was quite pleased as to how easily it sanded and it was plenty dry in two hours. Next time I'm building a small rocket i think I'll do the fins first and then glue them to the BT. My son (He is 6) wanted the Estes Skystryker and I found it a pain to sand the sealer with the fins on. Nothing like a radial 5 fin pattern on a BT20.:rolleyes:

Now that I think about it, a coat of primer should seal this nicely now since it isn't as porous.

Thanks,

I'll follow up with a picture as soon as its painted.
 
OK, I'll keep this brief. What Chris and Jeff said. Perfect. They nailed it. There's nothing more that I can add.

MarkII
 
OK, I'll keep this brief. What Chris and Jeff said. Perfect. They nailed it. There's nothing more that I can add.

MarkII

Although it pains me to agree with Mark, he's correct also.:D
 
When using on both sides, I like to first take floral wire (very thin) and put a short section in the root (end that goes on the rocket). Once the fin is "filled" both sides, stick the wire into a block of styrofoam. This allows both sides to dry and keeps your fingers off.
 
So, I figured I would try to use this on the fins of a new rocket but have a few questions.

  1. Do I seal the wood with a sealer first?
  2. Do I need to use a sealer after I use the filler?
  3. How long should I wait till I sand?

Package says I can sand in 15 minutes but that is for shallow repairs right out of the tube. I thinned it and painted it on.

I don't use sealer. I just put a dollop of filler in an old baby-food jar, thin it with a teaspoon or two of water until it's just a little thinner than hot dog mustard... brush it on the fins with a 1 inch paint brush and let it dry. As soon as it's dry enough to scratch with a fingernail, it's pretty well dry enough to sand, usually within 15-30 minutes. Sand MOST of it off-- you just want to fill the grain and dings, not really 'build things up' with it. I sand with 220 grit.

I never seal the stuff after I have the filler sanded out like I like it. Once the part looks and feels nice and smooth, and is thoroughly dry, (hour or two usually minimum) I go ahead and shoot it with a couple coats of primer, let dry 30 minutes to an hour (depending on the primer and conditions) and then sand again with 220 grit, before switching to 600 grit wet/dry paper dipped in water and blotted off, "damp sanding" the primer to a dull shine.

Once you get the hang of it, you can make balsa parts look like plastic...

I HAVE started CA hardening most of my balsa parts nowdays, but I've used the same filler/sand/primer/sand/damp sand method without it and it works fine.

Good luck and hope this helps! OL JR :)
 
Just following up with the picture of the rocket. Photo is not great but it looks a lot better in person because of the multiple coats of Future.

Rocket 001.jpg
 
Last edited:
To echo hcmbanjo's remarks.....

I use it all the time, but first I thin it down with a little bit of water to about the consistancy of paste or pancake batter. I use it to fill fins and nose cones, fill body tube spirals and to make fillets.

So to answer your questions, here are my observations/experiences:
1. I don't seal mine first, but you could if you wanted. I don't think it is neccessarry though, and my opinion is that it adds extra work. I think the wood filler is accomplishing the same thing that the sealer does.
2. No you don't, although (again) you could if you wanted to, but it isn't needed. I don't do it.
3. It depends on how thick you put it on and how much water you use when you thin it down, but my experience is that I usually let it dry about an hour. If it is still a little wet, it won't sand well.

A couple tips from my experiences:
A. Place a small amount of filler in a small disposable cup or jar for thinning, and add water very sparingly - a little goes a long way.
B. If you use it to seal balsa fins, do both sides of the fin at the same time to prevent warping.
C. Shortly after you apply it, you can dip your finger in water then rub it over the filler to help smooth it out. The smoother it goes on, the less sanding you will need to do later.

For me, I live in an apartment with less-than-optimal ventilation, so sanding sealer always stunk up the place and gave me a headache. That problem completely went away for me when I replaced sanding sealer with wood filler. No fumes and easy soap and water clean up.

Here are some fillets on a Big Daddy that I used watered-down wood filler for:

What kind of primer and paint did you use? The picture of Big Daddy is amazing.Alex
 
If you put paper skins on do you still have to put fill and finish or sealer on?
 
If you put paper skins on do you still have to put fill and finish or sealer on?


Nope. That's one of the beauties of papering fins, besides the added strength. If I'm going this route instead of Elmer's filler, I use full sheet label paper.
 
I am a big fan of papering fins. I do a "finish" sanding before papering and leave the edges alone. Primer and fine sanding take care of the rest. Some put a little CA adhesive along the edge.
 
do you leave the leading edge bare?
I don't usually wrap the paper around the edge, but I know some folks do. I usually leave the edge bare and seal the edges of the balsa and paper with some thin CA as Marlin523 noted. Then, sand the CA'ed area smooth with 400 grit. Follow with a couple light coats of primer. Too heavy on primer and the paper will become saturated and wet...something you want to avoid.
 
What kind of primer and paint did you use? The picture of Big Daddy is amazing.Alex

Alex...

Thank you very much! I appreciate your kind words. I have to admit - it does look pretty sharp in the sunshine!

I used PlastiCoat white sandable primer on that rocket. Unfortunately that stuff is no longer even made. :mad:

The paint was sprayed on with an airbrush. It is Createx "Irridescent Blue". It is a water-based acrylic paint so it cleans up easily with soap and water, without the nasty fumes.

It is topped off with a coat of Pledge (aka Future) floor wax.

Thanks again!
 
Alex...

Thank you very much! I appreciate your kind words. I have to admit - it does look pretty sharp in the sunshine!

I used PlastiCoat white sandable primer on that rocket. Unfortunately that stuff is no longer even made. :mad:

The paint was sprayed on with an airbrush. It is Createx "Irridescent Blue". It is a water-based acrylic paint so it cleans up easily with soap and water, without the nasty fumes.

It is topped off with a coat of Pledge (aka Future) floor wax.

Thanks again!

Thanks How does that pledge floor wax work?Is it better than a clear coat?Your big daddy looks darn nice.Have to admit that one.Alex:)
 
Thanks How does that pledge floor wax work?Is it better than a clear coat?Your big daddy looks darn nice.Have to admit that one.Alex:)

That is a tricky question, and everyone will have a different answer.

It can be applied with a paint brush, foam brush, paper towel, airbrush, spray bottle, etc. Everyone will have different application methods.

I make a lot of my own decals, and have tried a lot of different clear coats. Some of them attack and destroy the decals, and some don't. Also, some clear coats yellow over time. I have never had any of these problems with Pledge with Future floor wax. I am no expert so I don't know if it is stronger or heavier than clear coats, but for me, it is definitely easier to use. Again, you may get a lot of different opinions on clear coats vs Future too.

Try it sometime when you get a chance and see what you think. A little goes a long way, and if you don't like it, just dump it out on the kitchen floor for that just-waxed shine.
 
Alex...

Thank you very much! I appreciate your kind words. I have to admit - it does look pretty sharp in the sunshine!

I used PlastiCoat white sandable primer on that rocket. Unfortunately that stuff is no longer even made. :mad:

The paint was sprayed on with an airbrush. It is Createx "Irridescent Blue". It is a water-based acrylic paint so it cleans up easily with soap and water, without the nasty fumes.

It is topped off with a coat of Pledge (aka Future) floor wax.

Thanks again!

After you put future on do you polish it to make it shiny and smooth.:wave:
 
It already is shiny and fairly smooth, so I have never polished it. Has anyone else?
 
After reading this and trying it out, I'm starting to love this. Reason, it's faster than sanding sealer. One thin coat of the wood filler is all I need. So thanks guys and gals.
 
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