[R-390] Painting Knobs

[Barry]

Also, I cleaned the surfaces with acetone and let that dry (very quick drying time for acetone) before priming.

Barry - N4BUQ

> Jacques,
> 
> I allowed the primer to dry overnight, painted the top coat, set it in the sun
> for a couple of hours to help the curing process, let it sit overnight, and
> then tried the scratch test.  I'm not so much concerned about the top coat
> being all that hard at that point but I am concerned that the primer doesn't
> want to stick to the metal.  I wouldn't think the primer needs heat curing to
> stick, would it?
> 
> Thanks,
> Barry - N4BUQ
> 
>> Barry, IMHO, if you tried a "fingernail test" just few hours after the knob
>> was painted, it is normal.
>> Most paints can take a week or more to harden.
>> The trick I used was to put mine under the summer sun once they were painted
>> with the Krylon Dual-superbond, and they were "holding" such fingernail
>> test.
>> You can also use a small oven at 200F to promote the paint hardening.
>> 
>> 73, Jacques, VE2JFE in Montreal
>> 
>> Welp, I give up.  I tried priming one knob with a non-etching primer and a
>> top coat.  I can take my fingernail and easily scratch the paint off down to
>> the bare metal.  Sigh... Maybe I'll have them chrome plated.
>> 
>> Thanks,
>> Barry - N4BUQ
> ______________________________________________________________
> R-390 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/r-390
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:R-390 at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html