Posted by ajlorman (ajlorman@…>)
I have a loose mast step on my F-30 and wondered if anyone knew what
size pop rivet to use to replace the loose one?
Many thanks.
Al Lorman
Posted by katorpus (katorpus@…>)
— In freedomyachts2003@yahoogroups.com, “ajlorman” <ajlorman@y…>
wrote:
I have a loose mast step on my F-30 and wondered if anyone knew
what
size pop rivet to use to replace the loose one?Many thanks.
Al Lorman
Start with a LARGE diameter twist drill bit (about the size of the
head of the pop rivet)
While applying GENTLE outward pressure on the mast step, carefully
drill out only the head of the rivet. The outward pressure is to
keep the rivet from spinning. The large diameter bit limits the
depth of drilling needed before the rivet head disintegrates.
Repeat for each rivet on the mast step.
If the rivet shaft is “wiggly” in the mast, it may fall into the
mast on its own, leaving the hole behind.
If the rivet shaft is bound tightly to the hole, the rivet may have
been undersized (for the hole) in the first place (which causes it
to expand into the hole when set). If it won’t release with a couple
of GENTLE taps of a small diameter center punch, then you may need
to drill the center of the rivet all the way down. This is not fun
and difficult to accomplish, as the “nail” (in the center of the
rivet shaft) which compresses the rivet is, by its nature, harder
than the rivet shaft surrounding it. Use high quality drill bits for
this process.
Once you have the rivets out, figure out what size hole was drilled
into the mast (you can gauge this using a drill bit and working it
in by hand. If the hole is “egged” or the material around it has
deteriorated, you will need to overbore the hole with a larger
diameter bit.
Before you overbore, you need to make sure that you can obtain a
rivet for the “new hole size” and that the head and shaft size of
the new rivet is appropriate to the size of the hole and countersink
in the mast step AND that you can obtain a “short enough” rivet (in
the new, larger diameter) to appropriately fasten the combined
thickness of the mast wall and mast step.
If the rivet is too long, it will not compress properly and will
leave the step “loose”. Since the “workaround” for this is to stack
washers on the “back side” before compressing the rivet (from the
outside), it is obvious that this cannot be accomplished when pop
riveting into a blind space (like the mast).
Pop rivets are available in aluminum, stainless steel, and monel (an
alloy of copper and nickel). Don’t put stainless into aluminum.
Attaching aluminum (such as a mast track) to carbon fiber with
stainless is going to result in the deterioration of the aluminum
(probably in about the same amount of time (or less) that it would
take for the aluminum pop rivet to deteriorate to the point of
needing replacement). The difference is, instead of drilling out
rivets and replacing them, you’ll be drilling out rivets and
replacing them ALONG WITH the item you attached in the first
place.
Posted by katorpus (katorpus@…>)
— In freedomyachts2003@yahoogroups.com, “ajlorman” <ajlorman@y…>
wrote:
I have a loose mast step on my F-30 and wondered if anyone knew
what
size pop rivet to use to replace the loose one?Many thanks.
Al Lorman
Posted by ajlorman (ajlorman@…>)
Many thanks for your very helpful reply. I had a look at the step
yesterday and realized that I had never seen such large pop rievts
in a hardware store. Guess I’ll have to find something online.
Al Lorman
— In freedomyachts2003@yahoogroups.com, “katorpus” <katorpus@y…>
wrote:
— In freedomyachts2003@yahoogroups.com, “ajlorman”
<ajlorman@y…>
wrote:I have a loose mast step on my F-30 and wondered if anyone knew
what
size pop rivet to use to replace the loose one?Many thanks.
Al Lorman
Start with a LARGE diameter twist drill bit (about the size of the
head of the pop rivet)While applying GENTLE outward pressure on the mast step, carefully
drill out only the head of the rivet. The outward pressure is to
keep the rivet from spinning. The large diameter bit limits the
depth of drilling needed before the rivet head disintegrates.Repeat for each rivet on the mast step.
If the rivet shaft is “wiggly” in the mast, it may fall into the
mast on its own, leaving the hole behind.If the rivet shaft is bound tightly to the hole, the rivet may
have
been undersized (for the hole) in the first place (which causes it
to expand into the hole when set). If it won’t release with a
couple
of GENTLE taps of a small diameter center punch, then you may need
to drill the center of the rivet all the way down. This is not fun
and difficult to accomplish, as the “nail” (in the center of the
rivet shaft) which compresses the rivet is, by its nature, harder
than the rivet shaft surrounding it. Use high quality drill bits
for
this process.Once you have the rivets out, figure out what size hole was
drilled
into the mast (you can gauge this using a drill bit and working it
in by hand. If the hole is “egged” or the material around it has
deteriorated, you will need to overbore the hole with a larger
diameter bit.Before you overbore, you need to make sure that you can obtain a
rivet for the “new hole size” and that the head and shaft size of
the new rivet is appropriate to the size of the hole and
countersink
in the mast step AND that you can obtain a “short enough” rivet
(in
the new, larger diameter) to appropriately fasten the combined
thickness of the mast wall and mast step.If the rivet is too long, it will not compress properly and will
leave the step “loose”. Since the “workaround” for this is to
stack
washers on the “back side” before compressing the rivet (from the
outside), it is obvious that this cannot be accomplished when pop
riveting into a blind space (like the mast).Pop rivets are available in aluminum, stainless steel, and monel
(an
alloy of copper and nickel). Don’t put stainless into aluminum.
Attaching aluminum (such as a mast track) to carbon fiber with
stainless is going to result in the deterioration of the aluminum
(probably in about the same amount of time (or less) that it would
take for the aluminum pop rivet to deteriorate to the point of
needing replacement). The difference is, instead of drilling out
rivets and replacing them, you’ll be drilling out rivets and
replacing them ALONG WITH the item you attached in the first
place.