[Boatanchors] Wrinkle Paint

[Robert Downs]

RCA also used black crackle instead of black wrinkle on the BC-312-D and probably other models but not the -N which was black wrinkle.

Ron Allison and I placed two minimum orders (about 500 cans each time) for Signal Corps Green Wrinkle paint a few years ago.  
Their instructions were to apply two coats about 5 to 15 minutes apart with the equipment being painted NOT in direct sunlight and then to move the freshly painted objects into direct sunlight or into an oven.

Robert Downs


-----Original Message-----
From: boatanchors-bounces at mailman.qth.net [mailto:boatanchors-bounces at mailman.qth.net] On Behalf Of 1oldlens1
Sent: Monday, August 15, 2022 01:51
To: Donald Chester; boatanchors at mailman.qth.net
Subject: Re: [Boatanchors] Wrinkle Paint

   I wonder if the finish you are thinking of is what is sometimes Called crackle.  This is different from wrinkle in that it looks like dried mud.  This is the finish used by General Radio and was used by Hallicrafters for the SX 28  and elsewhere. I don't remember if I've ever read a detailed description of how it was done but seem to remember that it requires two coats and baking.  Perhaps related to the finer wrinkle paint in that both seem to use two components that shrink differentially.   Sent from my Galaxy
-------- Original message --------From: Donald Chester <k4kyv at hotmail.com> Date: 8/14/22  8:08 PM  (GMT-08:00) To: boatanchors at mailman.qth.net Subject: Re: [Boatanchors] Wrinkle Paint I remember using the GC product in the late 60s, both in a regular paint can and in a spray can.  It worked well in some spots, but I still had problems with non-uniform wrinkling.  It took a lot of  patience and numerous failures and wasted paint to finally achieve an even coat of wrinkling over a large area.In recent years I have had fair results using the stuff sold in auto parts stores, although the wrinkle texture isn't quite the same as what's on vintage equipment.  Something that worked well was to lay the sprayed panel outdoors in direct sunlight on a warm day.  Also placing indoors over the top of a large size vented propane heater in cooler seasons.  I think the secret is maintaining an extremely uniform application of heat over the entire surface area, which is difficult if not impossible with heat guns and IR lamps.I am still looking for a way to reproduce the wrinkling effect seen on a lot of 1930s equipment, particularly National products, that had a coarse and somewhat grainy texture. It shouldn't be rocket science to replicate it; if it was commonly done 90 years ago, it should still be possible to-day. I also recall a  similar texture on the cabinet of a 1970s-80s Swan transceiver. I don't know what chemicals could have been used pre-WWII that would be "banned" to-day. I believe if someone could find the original formula or recipe, a close replica could be concocted with what's available to-day. Apparently this is now a lost art that was buried with the last of the practitioners who produced it.Don k4kyvI recall seeing instructions in one or two 1930s radio books or magazines describing how to make your own wrinkle finish using ordinary paint, which is probably the only way it could have been done