My current project is just about ready to cover so it was time to take care of all the little nicks and dents in the balsa that come from handling the plane on the workbench. Usually these just get filled with putty but there's a method you can use to lift the majority of them first. I mentioned this method at the field and most people had never heard of it so I thought I'd mention it here. It's an old woodworker's trick.

Steam will pop most of those dings right back out. Using a clothing iron set hot enough to steam, if you wet the ding and then place the iron on it you'll hear the water sizzle. When the water is steamed out, remove the iron and like magic, the dent is gone. Larger dents may take several applications and some just can't be lifted. That's okay, now you have fewer that need filler. I always check the spot to see if it needs an additional application and frequently I can't even tell where the dent was in the first place.

I used to lay a wet paper towel over the area and iron it dry but lately I just use the wet paper towel to soak an area and then just steam the whole area out. The grain will also be raised and the surface will need a light sanding but it's a great way to prepare for filling and final sanding.

Just be sure that the steam is compatible with the adhesives you have used in construction.

Dave

It's really an old woodworker's technique, and an extension to this tip is for those dings and dents that give problems to get out, inject water into the balsa under the dent using a small syringe and then apply a hot iron and presto. I find that a monokote iron without the sock works great here.

Karol

One of the last things I do before covering an airframe is take a Q-tip and soak up a bit of water with it. Apply it to each little "ding" and bit of hanger rash and then use a hot trim iron run over the moist area to quickly raise the woodgrain. Do this over small areas at a time. Then go over the entire airframe with 320 grit sandpaper on a foam pad to remove the raised grain prior to covering. Using the Q-tip keeps the water in small concentrated areas and the heat does the rest.

Soft landings,

Joe

I try to save sanding and shaping for the last step and then put that part away unless i can cover it shortly after.

Ditto.

Karol

Just lick it. Balsa tastes funny though.

As an extention to this technique...

You can inject a small amount of water or ammonia into the dents/dings in your wing tips or leading edges that have already been covered on your old battle horse and steam them out too. If the tip is film covered, you may have to then pop the bubbles and re-iron the film covereing. If painted you can't usually use as much heat so the size/depth of dents/dings to be removed is reduced. painted surfaces need to be perforated with a small needle prior to heating or the steam will lift the paint....don't know how to fix that short of spot repair involving knives and repainting etc.

Nice tips!

I usually fix all the dents on one side, then fix the ones on the other side, then fix the ones on the otherside, then fix the ones on the other side. It's a futile effort. I'm my planes worst enemy. If I can get them glassed they are usually safe then.



Kelly

I have an old Rubber Foam seat cushion that I lay the fuselage or wing on, remove any balsa dings, turn the part over and remove the dings & dents from the other side. The Rubber Foam prevents additional dents and dings while covering the framework.

Ken

Just build warbirds, they are supposed to have dents and dings!
Jim S.