Fillets b4 Filler

[Paul Taylor]

I am at the point of spraying the filler coat on the Plane. Question is do I put my fillets on before I spray the filler coat of dope and zinc?

[Peter Nevai]

Logic would suggest spraying afterwards. Why do it twice. Just my thoughts.

Live Long And Prosper.

[Mark Scarborough]

Thats pretty good logic, HOWEVER, if your fillets are some form of epoxy, or cured material, be very carefull not to allow build up of dope on the fillets as by nature dope shrinks, and can pull away from the fillet material.
I agree in principle that filler after the fillets makes sense since you can then more effectivly eliminate any edge from the fillet material, just dont build up on the fillets themselves. and dont use shrinking dope in your filler.

[Paul Taylor]

OK. But then all the dope that I will put on this plane will be shrinking type dope. Randolph.

 

[Allan Perret]

OK. But then all the dope that I will put on this plane will be shrinking type dope. Randolph.

 

Randolph has both shrink and non shrink.  But they call it tautening and non tautening.  You only need to use shrink type dope when you want to tightening up a covering.  Everything else should be non shrink.  Using shrink for the complete finishing process leads to warps and filler lifting.

[Bill Little]

Hi Paul,

Guess I am the odd man out......... I put the fillets on after the primer/filler.  That way I do not get bubbles on the fillets.  Some white spackling compound will feather the edges if it is necessary.  Be very careful sanding the edges of fillets, you can actually sand the balsa beside the fillet so thin that a stress riser (folded wing) can occur.

Big Bear

[Peter Nevai]

Hi Paul,

Guess I am the odd man out......... I put the fillets on after the primer/filler.  That way I do not get bubbles on the fillets.  Some white spackling compound will feather the edges if it is necessary.  Be very careful sanding the edges of fillets, you can actually sand the balsa beside the fillet so thin that a stress riser (folded wing) can occur.

Big Bear

Masking or gaffers tape along the very outer edges of the fillets helps avoid this. You sand till you start sanding into the edge of the tape then ditch any block, wrap the paper around a finger and go real easy to feather the last little bit. Works every time.