Mark Robinson wrote:
>>> However, threadlock is only a special type of glue, so it won't work if
>>> the threads in the rotor casting are loose or corroded. The answer then
>>> is to re-thread the holes to a larger size, and use *red* Loctite (the
>>> permanent locking grade) to fix lengths of stainless steel studding into
>>> the casting. The two parts of the rotor can then be held together by
>>> nyloc nuts, on the underside where they're easy to work on.
>>>
>>> 73 from Ian GM3SEK
>>> http://www.ifwtech.co.uk/g3sek
>> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
>> When there is insufficient meat to drill oversize, even to a metric size,
>> then JB Weld or a similar hard epoxy can be used to fill the hole. Then
>> drill and tap to the original size. Ive done this with success to the base
>> of the RC5A-3 as well to the top bell of several HAM-M size rotators.
>>
>> Carl
>> KM1H
>> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
>
>Have you ever tried to helicoil it instead?
>
>
>Mark N1UK G3ZZM
Haven't tried that myself, because as Carl says, there sometimes isn't
enough meat around the existing hole to allow a big increase in hole
size.
I like the idea of the permanent stainless steel studs because there
won't be any more problems about removing and re-inserting steel screws
in corroded aluminum. With the external nuts, all the thread engagement
is steel-on-steel.
Coming back to Carl's point about hard epoxy such as JB Weld, the
material itself is great... but in this particular case, almost all the
new epoxy would have to be drilled and cut away again. I have never
trusted my own ability to cut a thread into a thin skin of epoxy to the
standards of workmanship required - especially for antenna rotors, where
any mistakes will be punished severely.
--
73 from Ian GM3SEK
http://www.ifwtech.co.uk/g3sek
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