# what sanding sealer is best?

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#### Justin

##### Well-Known Member
I'm working on a Duece and I want to make all the balsa really smooth before I start priming, so I was going to go buy some sanding sealer. You guys have any reccomendations?

For filling bigger spots some one told me Elmers Fill and Finish putty? Can you sanding seal over that?

Any help would be cool.

-Justin

#### DynaSoar

##### Well-Known Member
Originally posted by Justin
I'm working on a Duece and I want to make all the balsa really smooth before I start priming, so I was going to go buy some sanding sealer. You guys have any reccomendations?

For filling bigger spots some one told me Elmers Fill and Finish putty? Can you sanding seal over that?

Any help would be cool.

-Justin
Deft spray lacquer sanding sealer, sold at Lowe's.
It can go on thick, and if it runs you can wiupe up the runs with your finger while it's still wet, and it'll even out.

I spray the whole model, because it does a fine job of filling in sprials too.

I use two thick coats, saning after both (400 first time, 600 second time). I( haven't had any problems with paint going on it.

It dries very fast, but that's because it has a large amount of very light solvent. It stinks. Best used outside, or with a fan hood inside.

I tried Fill & Finish. I wasn't impressed. But the Deft did go over if just fine.

#### Justin

##### Well-Known Member
Thanks DynaSoar-
I'm gonna go get some and give it a shot.
-Justin

#### Stymye

##### Well-Known Member
.....and If you don't want to deal with the overspray and the smell,
fill and finish or any hobby balsa filler will work just fine and it works with any primer as well

#### Justin

##### Well-Known Member
I tried Aerogloss's hobby filler/sealer and had to put a million coats of it on without really good results. They say on the jar to wait 24 hours between coats too. It took forever..

I saw this brush on stuff my friend used to seal wood counter tops that I was thinking about. I can't remember the brand..It smelled pretty bad too. And REALLY shiney..

#### BobH48

##### Well-Known Member
I have used plain old spackle. I rub it into the balsa with my finger and then let it dry. Afterward, sand it until it's almost all gone. I then use Minwax Polycrylic as a sealer. I put on a couple coats and sand it with 600 grit paper. Then a final coat and it's ready. You can then prime, sand, and paint.

OBTW - It's a water based product and doesn't stink at all. Plus you can clean up your brushes with soap and water.

If your not too particular you can just paint over it without primer. Thats what I did on these.

#### Justin

##### Well-Known Member
That is a really cool fleet of bullpups.

I'll have to check out polyacrylic too.

#### FredT

##### Well-Known Member
Originally posted by BobH48
I have used plain old spackle. I rub it into the balsa with my finger and then let it dry. Afterward, sand it until it's almost all gone. I then use Minwax Polycrylic as a sealer. I put on a couple coats and sand it with 600 grit paper. Then a final coat and it's ready. You can then prime, sand, and paint.
What kind of paint goes over the Polycrylic? Being water-based, wouldn't it be a problem using the typical rattle can stuff (e.g. Krylon, PainterTouch, ect.)?

...Fred

#### BobH48

##### Well-Known Member
What kind of paint goes over the Polycrylic? Being water-based, wouldn't it be a problem using the typical rattle can stuff (e.g. Krylon, PainterTouch, ect.)?
Nope,

I've used Krylon, Walmart cheappie brand, Rustoleum, etc. and none of them has had a problem.

I've used it with primer first and without primer at all and it seems to work just fine.

#### jcsalem

##### Well-Known Member
I've had good success with the "All-Purpose Sealer" from Delta Ceramcoat. I paint on 3-4 coats using a foam brush with light sanding in between. It makes for a great smooth finish without a lot of work. I let it dry overnight before priming.

Unlike most sealers, it doesn't smell bad.

-- Jim

#### mike_bar

##### Well-Known Member
Originally posted by BobH48
(snip.) I then use Minwax Polycrylic as a sealer. I put on a couple coats and sand it with 600 grit paper. Then a final coat and it's ready. You can then prime, sand, and paint.

OBTW - It's a water based product and doesn't stink at all. Plus you can clean up your brushes with soap and water.
Hi Bob,
Which sheen do you use (gloss, semi-gloss or satin)?

Minwax® Polycrylic® Protective Finish

I suppose the satin would be best as an under-coat. Thank you for your comments and great modeling tips.

#### Silverleaf

##### Well-Known Member
I'll 2nd the use of Deft Spray Lacquer Sanding Sealer.

Its one of the best sealers I've ever used, and as a veteran of many applications of Aerogloss "dope", in the long run its much quicker and the results are always what I expect. I've used it for the last 4 or 5 years, and will never go back.

Cheers,

#### BobH48

##### Well-Known Member
Originally posted by Mike_BAR
Hi Bob,
Which sheen do you use (gloss, semi-gloss or satin)?

Minwax® Polycrylic® Protective Finish

I suppose the satin would be best as an under-coat. Thank you for your comments and great modeling tips.
I use the gloss. I have changed my finishing procedure a little since this was posted.

I use just one or two coats of Polycrylic on the bare wood and then sand it smooth. It soaks in and hardens the balsa in my opinion.

Then followed by Fill N' Finish and sand it smooth.

Then a single coat of Polycrylic to seal everything.

Then your usual prime and paint procedure.

I have used Krylon, Rustoleum, Walmart cheap brand, Walmart better grade cheap brand and never had a problem with compatability over Polycrylic. I do let it cure for about a week before painting but I don't know that it is necessary.

#### Micromeister

##### Micro Craftman/ClusterNut
TRF Lifetime Supporter
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Juatin:
Aero-Gloss Balsa Fillercoat # 70-4 in the 3.5 zo jars. #70 is a heavy solids, very thick filler, not just a sealer. 3 to 6 coats on the worst balsa grain is always completely fills the grain. NOT the balsa filler/sealer. which is water thin with only a small amount of solids. #70 has to be stirred with a stick to keep the solids suspended. Normally 3 brushed on coats applied one after another as soon as the pervious coat dries 10 to 20 minutes will fill nearly all grain. Sanded with 220, 320 and 600 to a babies but smooth and hard base. Apply 3 coats to raw balsa without sanding, after the 3rd coat dries an hour or so sand until your happy with the smoothness or you hit balsa, If you got to the raw balsa apply the last 2 or 3 coats, let dry, sand smooth and paint.

If you're spray painting anyway don't bother with a filler. Any of the Cheap (.99/can or less) automotive Hi fill primers will fill the worst grain with 3 or 4 good coats, sanding with 220, 320 and 600, quicker then even fill-n-finish. I've been using K-mart "Smooth n Silky" Gery, bown, and black primers lately. alternating primer colors let you see the level you've sanded into. completely fills bodytube wrap lines also with a couple extra coats

#### Manwithbeers

##### Well-Known Member
Originally posted by jcsalem
I've had good success with the "All-Purpose Sealer" from Delta Ceramcoat. I paint on 3-4 coats using a foam brush with light sanding in between. It makes for a great smooth finish without a lot of work. I let it dry overnight before priming.

Unlike most sealers, it doesn't smell bad.

-- Jim
Another Vote for this product.

I recently found this All-Purpose Sealer at Michaels. It was inexpensive. I bought it because it was water based and not smelly at all. When I started using it I found it to be thicker than balsa dope or the sealer I usually use so I need fewer coats. I like how it dries and sands as well. That's 4 Pros for this product but there is 1 Con. It doesn't seem to add strength like my other sealer does. That might be only my perception though. I use a couple primers over the sealer and I've never have a reaction.

Delta Ceramcoat All-Purpose Sealer is worth trying for a brush on sealer.

Layne

#### rbeckey

##### Well-Known Member
I bought a water based sanding sealer in the WalMart craft section. Cheap, easy, and works well. I usually sand lightly, then use two coats of sealer, sanding after each.

#### Justin

##### Well-Known Member
Micromeister-
I'm a fan of cheap primer too. I use color works generally for grey. But it never seems to hit deeper grain in balsa even with a million coats. There is allways at least a trace of the grain unless I fill with something. I guess I'll have to try some of Kmarts primer. I have never used it. It may be slightly thicker than color works. Or just all around better quality.

Krylon and Rustolem make primers that seem to fill well (at least better than color works), but tend to be kinda gummy when sanding, unless I give them forever to dry.

What I have been doing is tring to smooth the best I can before priming, then priming with color works grey for the prime/sand/prime/sand/prime/sand phase, then priming with a smoother heavier primer (usually Rustoleum white), then painting.

This works pretty well, but I'm looking for smoother fiishes still.

I have tried Elmers fill and finish before the grey phase. It wooks okay.

As I mentioned earlier the Aerogloss stuff was not so good. But I may have used the wrong Aerogloss.

I still have yet to try some of the suggestions I found here at the forum. I'll post any results. Thanks.

#### BobCox

##### Well-Known Member
KILZ primer goes on thick, dries quickly, and sands down easily without gumming up the sandpaper.

#### Micromeister

##### Micro Craftman/ClusterNut
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Originally posted by Justin
Micromeister-
What I have been doing is tring to smooth the best I can before priming, then priming with color works grey for the prime/sand/prime/sand/prime/sand phase, then priming with a smoother heavier primer (usually Rustoleum white), then painting.

This works pretty well, but I'm looking for smoother fiishes still.

Justin:
Try this method, instead of sanding between coats apply 3 primer coats, heavy wet coats,without sanding. let them dry about 30 minutes. Sand to the finish you want starting with 220grit then switch to 320 as you near the smothness your looking for. If some grain or tube seam still show apply another 3 coats. I can't remember the last time I've had to shoot more then 6 total primer coats (2 spray sessions) on any model. I'm sure I've said this before.. I haven't used any type of filler material of any kind for more than 5 years. On most sport and Scale models up to BT-80 only Hi-Build grey, brown and black primers, finishing Scale models with White fine grain primer then the color coats. I do not accept even the slightest hint or grain or bodytube seam lines, holes in fillets or other surface imperfections. This is especially true on micros and scale projects which are generally examined after finsihing with a more critical eye Finishing is without doubt the most time consuming part of modeling. The degree of finish is in direct proportion to the time spent. Each modeler must decide on how much time is too much, or Obsessive the process starts with the base materials progressing all the way to the finial decal applied.

Speaking of base materials, have you given any thougth to switching the supplied Balsa stock fins to Basswood? Basswoods finer grain is slightly heavier then Balsa but the trade off in a stiffer, stronger and easier to finish wood make the switch worth the little extra money and time to cutout a set of fins.
Hope this helps a little.

#### Fore Check

##### Well-Known Member
I use Folk Art (brand) aerosol sanding sealer almost exclusively. I really, really like it.

Build the model, mask off the body tube or other places you don't want sealer on, and apply. I give it three coats for balsa, and sand with 400 grit after each coat dries (about 30 minutes to 2 hours drying time, depending on humidity.) The stuff is awesome!

I buy it at Michaels.

#### JRThro

##### Well-Known Member
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Originally posted by DynaSoar
Deft spray lacquer sanding sealer, sold at Lowe's.
It can go on thick, and if it runs you can wiupe up the runs with your finger while it's still wet, and it'll even out.

I spray the whole model, because it does a fine job of filling in spirals too.

I use two thick coats, saning after both (400 first time, 600 second time). I( haven't had any problems with paint going on it.
This sounds like what I'm looking for. I don't typically fill, finish, or paint my rockets, so I would really like something that's simple to apply and that doesn't take a million apply/sand/apply/sand cycles to get it done.

Does "go on thick" mean that sanding the fins, etc., beforehand isn't necessary?

#### Silverleaf

##### Well-Known Member
Does "go on thick" mean that sanding the fins, etc., beforehand isn't necessary?
It isn't necessary to sand the fins beforehand because the Sanding Sealer will raise the Nap of the wood, which allows you to sand it smooth.

That being said, I always pre-sand my fins before attaching to the airframe, just so their close to the finished final look. Then I spray the entire model, let it set for 30 minutes, sand and repeat.

In your case, since your not greatly concerned with finish, it will still make for a smoother finish, which can help with altitude and aerodynamic stability.

Cheers,

#### ccoffin

##### Well-Known Member
My normal sealing process for average thickness balsa fins is to apply one or two coats of watered-down Elmers Fill N Finish and sand smooth between coats. I do this before attaching the fins to the airframe. This fills most of the grain and also normally corrects any imperfections created when cutting the fins, etc.

The next step is for strength and to fill whatever grain is left. I apply Bob Smith brand InstaCure Thin CA (blue bottle) to the surface of the balsa. I do this by just applying it to the surface and then immediately wiping the excess with a paper towel. This smooths it out and creates a thin layer that dries very quickly. I try to work my way from one side of the fin to the other and will wipe the CA towards the balsa that hasn't been covered yet. Don't CA the root edge of the fin or you might have problems getting it to stick to the airframe later!

The CA will penetrate into the balsa and strengthen it considerably. You should be able to touch the fin without getting stuck to it within less than 5 minutes. A key here is to sand the fin smooth within 15 to 30 minutes. The CA is much easier to sand sooner since i believe it takes it a few hours (i've heard up to 24 hours) to dry fully.

Something else that i've been doing on recent builds is to leave a line of balsa along the root side of the fin CA free. What i mean is the sides of the fin closest to the root edge, not the root edge itself. This is to allow the glue you use for a fillet to penetrate the balsa as well since it may be a different glue than CA. The amount of fin you leave should be determined by the size of the fillet you intend to produce later in the build.

As for primer, i have tried quite a few (though i still need to try Kilz) but i am stuck with Plasti-Kote Spot Filler and Primer (see here: http://www.rocketreviews.com/tips_emrr.shtml#kraft_paper_tubes). The stuff is awesome! It can be dry and wet sanded. When sanding it dry, it turns into powder instead of the gummy stuff that sticks to your paper. You can actually get this primer to shine like paint when you wet sand it. I've done some side by side comparisons with krylons and duplicolors and this stuff wins in all categories. I still need to try Kilz though .

One side note here:
I recently built a competition model that had super thin balsa fins (1/32" if i recall). I tested Fill N Finish on some of the scrap balsa from the kit and it warped pretty badly. I decided to just use CA by itself and it did the trick perfectly. I think if i hadn't used CA on the fins they would have broken on the first flight easy.

More Fun:
I have experimented some with how much water to add to Fill N Finish and have found some neat things.The more water you add, the easier it is to sand later (i know it sounds obvious but it didn't occur to me until a while after i started using it). I found that applying it somewhat thick like maybe chocolate syrup is good for the fins as i described above. For thin fins, you may want to go thicker or even straight from the can to prevent warping the balsa.

Another nifty thing i found is using it for smoothing fillets. The first time i tried using Fill N Finish for fillets i didn't use much water and the fillets were very difficult to sand into shape. I tried again though after hearing someone mention thinning it more and it works great. This time around i used almost a water consistancy and it worked great! There are a couple of drawbacks though. It takes longer to dry and requires up to three or four applications (depending on how big you want the fillet). The other drawback is that it's weak (but that was sort of the purpose too ). As long as you applied a good fillet of glue under the Fill N Finish, everything should be good. The next step would be to sand the fillet smooth. I generally take an 1/8" dowel and wrap it with 400 grit. This will easily shape the fill n finish fillet. The only other step i would recommend is to put a drop of thin CA at one end of fin fillet and let it run all the way across the fillet. This will strengthen the fillet, as well as the thinned fill n finish fillet.

#### Rob Fisher

##### Well-Known Member
For a very easy method with no fumes & water clean-up I use Elmers carpenters wood filler in white. It comes in a tube. All I do is squeeze a little into a cup, add a little warm water & stir it to an almost paint-like consistancy. Brush it on like paint with a brush, let dry & sand. I've gotten great results with just one coat! It's so much simpler.

#### stevem

KILZ Spray Primer is all I have come to use. I have tried most of the methods listed in this thread and I find that the KILZ spray primer is all I need. Fills the balsa and the tube spirals, dries quick, sands easily. Kinda spendy at $3.99 a can abd it goes fast. I use Krylon and Testors paints and have had 0 compatibility issues. #### Rob Fisher ##### Well-Known Member Originally posted by Rob Fisher For a very easy method with no fumes & water clean-up I use Elmers carpenters wood filler in white. It comes in a tube. All I do is squeeze a little into a cup, add a little warm water & stir it to an almost paint-like consistancy. Brush it on like paint with a brush, let dry & sand. I've gotten great results with just one coat! It's so much simpler. Here's a pic for ya.-Just one brushed on coat, a little sanding & some primer. #### mike_bar ##### Well-Known Member Originally posted by stevem KILZ Spray Primer is all I have come to use. (snip.) Kinda spendy at$3.99 a can abd it goes fast.
I have been reading this message thread as well as others on painting, priming and sealing. It seems most folks use rattle-can, spray on products. Maybe I am cheap, but how about brush on primers? This surface will be sanded and worked so I do not see why the brush-on cannot be used as well. This is not addressed to stevem but to all.

Thanks for any suggestions.

PS- I love the spray-on Kilz primer.

#### Silverleaf

##### Well-Known Member
There is zero problem with using a brush on Primer. I truly think the only reason its not mentioned that much is because most prefer the spray /airbrush method.

When I could easily get Aergloss Sanding Sealer, thats all I'd ever use, and sadly, when a local craft store cut back on their entire rocketry/modelling section, I bought everything they had. Wound up spending like 200 bucks but got the entire Aerogloss line. those paints went way too fast over the last 10 years.

#### AlexM

##### Well-Known Member
I used Elmers Fill and Finish thinned down enough that I can just pour it on and rub it in with my finger. Let it fry for a half hour, then come back and sand with maybe 600 grit paper for a few seconds, and it is extremely smooth.

#### gpoehlein

##### Well-Known Member
Originally posted by jcsalem
I've had good success with the "All-Purpose Sealer" from Delta Ceramcoat. I paint on 3-4 coats using a foam brush with light sanding in between. It makes for a great smooth finish without a lot of work. I let it dry overnight before priming.

Unlike most sealers, it doesn't smell bad.

-- Jim
A third vote for this product - it goes on just like the old aerogloss filler, but without the headache producing smell OR eroding the white glue fillets. I just picked up a large bottle (8 oz for \$6) at my local craft store (look in the same area with the tole-painting supplies). So far, it seems to produce a nice smooth finish with no warping. I think this is a new favorite!

Greg