[furboo]

I'm building a pedal airplane for my grandson, something like:

Home

I'm using "Big Box" pine plywood, and I want to fill the grain so that when I prime/paint, absolutely no grain pattern or knots are visible. What's your favorite grain filler?

What I've tried so far on samples: Sand down to 220, after which either plaster of paris (cheap) or Timbermate (not so cheap). After painting, with either I can still see the grain, although I don't claim that I'm applying either correctly.

 

[Herb Stoops]

Have you tried Drywall Spackle (taping mud). I have used it for years on hollow core mahogany veneer doors, sand, and then semigloss interior wall paint and they come out as smooth as a baby's rear. The wall paint is non toxic too.
Herb

 

[furboo]

I'll try that Herb, thanks!

 

[Stick486]

how to..
Filling Wood Grain for Perfect Finishing
better product...
https://www.woodcraft.com/products/behlen-pore-o-pac-paste-wood-grain-filler-natural-quart

 

[DesertRatTom]

A few years ago, I used the linseed oil slurry described in the article and got a really beautiful glossy finish. But is also rubbed it out very well with a sof, cotton cloth, which put a sheen on the drawer fronts, face frame and flat surfaces. It created a very light finish on what I remember as birch. I used 220 and 320 grut for the two sandings. I'd read somewhere that the 320 produced finer particles that filled very well. I have also used Timbermate on frames, but it dries fast and I can't imagine using it on large surfaces. Looking forward to seeing the projet.

 

[jj777746]

I'm building a pedal airplane for my grandson, something like:

Home

I'm using "Big Box" pine plywood, and I want to fill the grain so that when I prime/paint, absolutely no grain pattern or knots are visible. What's your favorite grain filler?

What I've tried so far on samples: Sand down to 220, after which either plaster of paris (cheap) or Timbermate (not so cheap). After painting, with either I can still see the grain, although I don't claim that I'm applying either correctly.

@ furboo.Hi Rob,this is very timely for me as I am almost finished a patio bench seat for my wife & today I ran out of wood filler when filling counter-sink screw"holes".I've used spackle previously,as mentioned by @herbStoops,thanks Herb,but "shrinkage"dents are a problem even when over-filling.I used to mix spack-filla with water & paint but cant remember the ratio.If someone has further advice on this it would be most welcome as it is much cheaper than the alternative.Thanks Rob for allowing me in your post.Jamesjj

 

[Multiwood]

Rob I have used Bondo like you get at an auto parts store. They also make a wood Bondo
I got at Ace hardware stores.

 

[tomp913]

Rob I have used Bondo like you get at an auto parts store. They also make a wood Bondo
I got at Ace hardware stores.

I can vouch for how well this works.

https://www.amazon.com/gp/product/B0007ZG9T4/ref=oh_aui_detailpage_o00_s01?ie=UTF8&psc=1

Be aware though that it dries pretty quickly so don't think it would work on large surfaces. Mix smallish batches and, VOE here, do NOT use the same mixing stick for successive batches, the residual material on the stick will flash over the new batch.

 

[tomp913]

There is a good article in the April 1995 issue of Fine Woodworking covering painted furniture in which the author covers the use of automotive body fillers for his painted furniture. There was also an much earlier article on the same subject (which I can't find at the moment) but the 1995 article probably has more current materials recommended. As far as using drywall joint compound, why not look at thinning the compound down and applying it with a roller? - I've seen articles by Myron Ferguson covering this technique and it looks as if it would work well for relatively large surfaces, Watching some of the car building shows on TV, it looks as if they apply the body filler to relatively large surfaces, it seems to spread out nicely and sand fairly easily so that might be the better way to go - find a friend who does auto body work and ask for his recommendations, apparently the newer materials are pretty flexible and should work well on wood.

 

[furboo]

Guys, lots of good ideas here.

I have some extra drywall mud, so I'm going to try that for the main surfaces, but I'm thinking I may used a better wood filler for where I need some strength (plywood edges of wings, rudder, etc.). I had thought of Bondo, but I was a little afraid of keeping it thin enough to avoid too much weight gain....not that this thing is going to fly :wink:

I should have mentioned that I considered products such as AquaCoat, Pore-o-pac, Behlen filler, Crystalac, etc., but these are pricey (at least for this project). I got the idea for Plaster of Paris from a May/June 2005 article in FWW, where their first choice is fine pumice rubbed in with boiled linseed oil. I think all of these choices are good for furniture-quality projects, particularly where you want the filler to be somewhat transparent. I was hoping for something a bit easier for painted pine.

Thanks for all the advice!