[Alberg30] Mast Step Bolts

[Crufone at aol.com]

Joe,
Would like to add a couple of comments.  Mask off the area around the mast 
step carefully.  Once tapeze or cutting fluid mixed with al corrosion gets 
onto your weathered getcote your will not be happy with the mess and stains 
that it will make on your coach roof!!!!!!!!!!!!!!

You will be taping into a blind, dead end hole.  You will need a Starter and 
a Bottoming Tap.  The starter tap has a long lead of cutting threads and is 
used first.  This is then followed by a bottoming tap which has almost no 
lead.

The blind hole also traps all the cuttings and junk.  DON'T BE IN A HURRY, 
YOU WILL ONLY HAVE ONCE TO GET IT RIGHT, SO BE CAREFUL.  Tap a little; one or 
two turns, turn 90 degrees and then back off to clear the tap then go the 180 
degrees and then back 90 and then 180 and back 90 and then 180 and so on.  
After your 720, yes your fouled me again,  remore the tap entirely out of the 
hole and clean out all debris.  Compressed air blows stuff all over the place 
and also on your coach roof so a vacuum is better.  When the hole is clean 
add more cutting oil and go in another two turns further and so on.  NB the 
cuttings must be cleared because they will clog the tap and eventually tear 
the metal and ruin the newly cut threads.

Most important off all.  Because you are taping a blind hole measure the 
depth and then mark the tap before you begin.  A real heart break is when you 
bottom the tap and don't realize it, you keep turning the tap which begins to 
turn in place, because it is bottomed, and you strip out all the new threads 
that you have just cut. Be very careful as you reach the bottom of the 
hole!!!!!!!!!!!!!!!!!

This is very easy.  I only mentioned these pit falls because you will be 
taping a relatively soft metal - Aluminum - with a HSS tap and can easily 
tear up the Aluminum.

Michael #133
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