[Public-List] Damn screws

[George Dinwiddie]

Thanks Gord and Hans,

On 6/1/18 9:06 AM, Hans Thomas wrote:
> Penetrating oil and a hammer screw drive (the battery operated ones
 > work great but make sure the drive is well fitted to the screw).

I tried my 1/2" hand impact tool, but don't have a bit small enough to 
fit the screw


> When you reassemble use never seize or some other anti seize compound on screws.

I generally like to do this, but wonder about the addition of more 
metals to the mix. I've also used RTV caulk or Vaseline in a pinch. I've 
never found anything that seems to work between stainless and aluminum.

> Whale pumps are actually a bit of a maintenance hog. I open mine up
> and inspect/clean/make sure screws turn twice a year.
Perhaps that's my problem. I expect things to keep working. I don't have 
the time to rebuild everything all the time.

>> On Jun 1, 2018, at 6:00 AM, Gordon Laco wrote:
>>
>> Normally I’d suggest heat - but that will destroy the rubber flap
>> valve.   Are you replacing it?  Perhaps you don’t care if the valve
>> that’s in place is destroyed.   I had success heating a cast
>> aluminium windlass body as a step toward removing an oxidized-in
>> stainless screw in the chain stripper.
I'm hoping to reuse this flap valve, as it's still working. It's the 
other one that had taken a set and quit sealing, and I seem to only have 
one spare at the moment.

I'm taking it out so I can clean and repaint the inside of the pump 
since I've got the unlikely circumstance of repairing it while at the 
dock instead of at sea.

>>
>> I recall an article in a yachting magazine about fighting reluctant screws…
>>
>> #1 - Never let the screw ever think there is any possibility it
>> might win.  It is going to lose and come out and there must never
>> be any doubt about that either in your mind, or on the part of the
>> screw. >> #2 - Address the screw.  Cursing is beneficial, the more creativity
>> the better… volume is not required, in fact silent cursing may be
>> the most effective preamble of all.
I've done this part well.

>> #3 - Get the screw’s attention.  Place a properly fitting screw
>> driver in its head, and rap sharply with a hammer. (this is
>> actually good advice because the shocks will tend to dislodge the
>> aluminium oxide that is gripping it) >> #4 - soak with penetrating oil, and let it sit a bit, then go back
>> to #2 and proceed again until final victory.
I'm wondering if the rubber flapper is preventing the penetrating oil 
from penetrating the metal-to-metal contact.

>> #5 - apply gentle but relentless torque with your screw driver,
>> sharply rapping with the hammer…be careful with the torque, you
>> could break the screw.  you may be tempted to put a wrench on your
>> screwdriver for leverage… this is dangerous.  A broken head means
>> the screw won a round.

The screwdriver has already slipped once, slightly damaging the slot. I 
fear that this has given the screw courage.

  - George

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   When I remember bygone days                         George Dinwiddie
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