This is something
brought to my attention by our friend Nei Biazetto. Although most of us
have already heard about it, I for one have never seen the actual
consequenses. I'm talking about the usual method of glueing weights
inside models to avoid the well known tail-sitting
problem. The most commom method to prevent it is to glue lead balls in
hidden spots of our model to make its center of gravity remain between
the landing gear legs. This makes the model to sit properly on the
wheels, instead of laying back on its tail. P-38s, Moskitos and B-25s
are prime examples...
Well, if you like to use white glue to cement the lead in your models,
stop reading now and do yourself a favor: keep using white glue. If
not, be aware that a very undesirable phenomenon will probably happen
to your models (or already have - cross your fingers).
I don't know exactly what is the chemical reaction which takes place in
the dark interior of our models, but it seems to form an ever growing
layer of oxide (or salt?) visually similar to what happens to your car
battery terminals: a white, brittle stuff... The fact is that the stuff
doesn't stop growing, until it fills up the model cavity where the lead
was glued, and increasing the internal pressure to the point of
actually breaking your model apart.
Nei showed me a couple of models in his collection suffering from the
These are valuable examples. Look at the engine nacelle of this 1/72
Focke-Wulf Ta-154, it has broken along the seam line, the same
happening to the fuselage (in spite of a previous Nei's attempt to
correct the problem):
Nei told me that the process
takes time. About 5-10 years in his cases. And it is an ugly view. This
Heinkel He-219 literally exploded beyond repair:
And before you
try to repair the crack, remember, the stuff will keep growing inside
your model. Always use white glue or even better, avoid lead.
I recall reading somewhere a set of directions to be followed by
professional ship modelers in order to have their models accepted by
museums. That included a tacit "No lead parts" and even a "No paints
with lead content". Now I know why...
I hope you find this tip useful. And if you have more information or
photos on the subject, please drop me a line.