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Applying Progrip ( Gil)

Peter,

Applying Pro-Grip is best done with at least 4 hands. That suggests
a significant other, wife, fellow sailor or intelligent child as a helper.

Most of the pieces that you are putting down are roughly rectangular.
Three hands hold their corners up and the fourth smart hand is carefully
putting down the first corner.

In addition to avoiding moisture, avoid applying Pro-Grip in any breeze
at all. The stuff just loves to whip around and stick to itself. You can
never separate it again after it has stuck to itself.

Clean tin cans are handy and removable weights to help hold the
sheet of Pro-Grip down while you wait 15 minutes or more for the
glue to dry enough to be ready to apply. You can wait a bit longer
until any wet spots in the glue have lost their gloss indicating that
they are dry.

Do not count too heavily on the pieces remaining the same size
after you have applied the glue. Ian Renilson told me that the
pieces become larger with the glue on them. My own experience
says that they return to about the original size. Your mileage
may vary.

Wrap the Pro-Grip that is along the rail right around and to the
underside of the rail. It will be less apt to peel loose later when
your size 47s are tromping up and down the rail.(;-) In addition,
you can precisely follow your glue line on the topside with one
edge of the Pro-Grip and be a little less precise on the less visible
underside.

Gil Woolley
USA-204

Applying Progrip

Hi All!

I just finished our boat with ProGrip all over
(meaning the complete back deck and all the way
up to the shrouds and the compete inside bottom).

I started to do one side with Henkel Tomsit R710.
The 2-component glue is easy to work with, but it
did not stick after one hour. After about 2 1/2
hours the cement started to become 'tacky' enough
to keep the foam on the shape of deck (wich
happened to be some time after midnight...)
The next day I did the inside of the boat with
the Henkel glue. Here on then early flat areas
it worked very well and easy. There is enough
time to move the material in place and then just
wait to let the cement cure. You can even do this
single handed, without any assisiting person.

The other outer Deck was done with the contact
glue Terokal 2444 (wich looks like Pattex, smells
like Pattex, comes out of the house (Henkel) like Pattex).
It is important to have a helping hand here to
handle the sheets (I made the area in two pieces)
but the work went much faster than with the Tomsig glue.

There is quite a lot of room for improvement to
make the work look better, but the sheets were solid on the boat.

This Saturday was first test sail (including the
first Club regatta of the season...)
I was surprised about the no-slip effect of the
material - I never felt so safe on the boat and
nothing seems co come off so far.

Looking back from my point of view I would say
that the Tomsit is nive to work with when you are
on your own, but when working in a team, the
Terokal 2444 (Pattex???) is the faster solution.

With best regards from Osnabrück,
Uwe

Progrip on older Rondar Decks

I want to pro grip an old rondar. It has pimples on the decking, so do
I need to sand down the pimples or have those who have done it found
that it sticks ok without having to do so. Reminder of best adheshive
please. Thanks.





Rob,

Gelcoat is heavy and there has to be a very thick coat in
the areas where the old moulded non-skid  is located
(Pimples? Please, that is so teenager. I'd like to forget
that). I would be very inclined to sand the stuff hard
to reduce weight but don't go into the glass underneath.
Just enough to barely know where it is. # 60 grit.

A random orbital sander with hook and loop disks is excellent
for this. If you don't have one yet, this is the perfect justification
to buy one. You will wind up using it for lots of projects.
I formerly bought packs with 5 disks but now I buy 25 at a time.

Gil

the best glue for progrip is Dunlop thixofix applied with a
paintbrush and allowed to surface dry properly as this stops
the solvent in the glue bubbling the progrip up off the deck of your boat.
if anyone needs progrip I now have all the colours in stock and also have
Thixofix
Regards
Chris

Chris Somner Dinghy Services
40A Salterns Road, Poole, Dorset, BH14 9HF
T: (01202) 736704
M: 07941 301742

Cracked Mast


Here is a picture of a vertical crack around the gooseneck of a
procter C mast. I have been given advise to strap stainless around it
and I'm leaning towards that but, I've also been told by a respected
boat rebuilder, in my area, to have it wielded by a paticular person.
I do understand the properties of annealing metal or glass and that no
way could I fit a 22' mast in oven so, I'm throwing this out here to
see what you would do.
 
 cracked_mast.jpg


Dave!

let us take it that way:
The mast will go - the big question is only, when....

All you can do is drilling a hole (3/16'' (or 5 mm)) just at the end
of the crack (in doubt a bit further away from the visible crack
line) to_hopefully_stop the crack growing.

A very skilled alloy welder_may_be_able to weld the damage. But this
changes the properties of the material and you can expect the
appearance of a new crack somewhere in the proximity .

I personally would not expect any help from a S/Steel (or whatever)
cladding on the damage except you can not see it any more. Duck Take
will have the same effect, is cheaper and easier applied.

In my humble opinion you should not trust that bit to more than the
usage as a flag pole.

This remains me of my good old Boeing 707 repair days.
This is a typical case of stress corrosion cracking.
It started at the top where you can see deep corrosion
pits. The pits created stress concentrations and this
started the cracking.

The first think you should always do is to drill a
hole at the tip of the crack. About 3mm diameter
should do it. This will stop the crack from growing at
least for a while. There is for example a smaller
crack running forwards at the bottom edge of the upper
fitting.

Once you stopped the cracks you can think about
replacing the material that is not effective any more.
The bolts in the area look quite chunky and I'm not
sure what they are there for. If they carry
signifficant loads I would wrap a sleeve around the
outside and rivet it with blind rivets. I would use
aluminium sheet and pop rivets. Aluminium because it
has the same stiffness as the mast and you don't have
galvanic corrosion problems. If you use stainless your
patch is much stiffer than the mast tube and you will
get high loads in the patch. Welding is usually not an
option because as you mentioned you would have to heat
treat the mast afterwards to get the strength in the
heat affected area back.

Good luck,

Continue Reading

Stiffen up the Centerboard case


My general idea is to peel up the pro-grip, cut a big hole in the
floor of the cockpit, and add one or more floor frames to brace the
CB trunk.

Questions

How many frames should I add?

What is the best to use for the floor? 3mm ply or glass-foam-glass
sandwich/
How to attach the floors to the CB case and hull? use glass tape or
is a fillet of glass-filled epoxy good enough?

Is epoxy the right glue or should I use something else?


Kirk,
Here's the way I'd do it- using my limited
boatbuilding skills :-).
Can't you just cut a few width ways slits (the same
width as some ?6mm plywood), with a skillsaw/ jig saw.

Then cut a bigger fore and aft cut along the case, so
you can get ya hand in (for gluing/coves), and put
some fore and aft stringers around the case. To finish
just Epoxy/ glass (did you say Carbon- Gil?- sounds
good to me for an older boat!) her up.
If weight is a problem- just sand all the Gel coat off
under the progrip to help.
The best guy to ask is probably Joachim - the guru,
if you can track him down.
Regards,
andyg


Kirk and everyone.

I do feel badly about not tumbling to the lack of
structure before Kirk bought the boat. I do tend to
go around sticking a camera inside boats to see how
they are built. I just did not do it soon enough.

Kirk, we need to double our boats up on my trailer so we can
go demo some prospects. I have not talked to them yet so I
do not know when.

While we are loading, you can look inside Challant to see how
I did that one a few years ago. I cut a thwartship piece of
cockpit floor out and then bonded in two bulkheads just
in front of the cut and just aft of the cut. Flanged the
underside of the deck and glued the removed piece
back into the cockpit floor. That was about a 6 month
job of thinking and about 1 day doing.

The good news is that there is no blocking bulkhead from
the front of the cockpit back to the region which needs
stiffening.

I am thinking that it might be possible to build a transverse
I beam which closely fits between the bottom of the boat and the
cockpit floor. Said I beam would have one very rigid side
to butt up against the side of the centreboard case. The
I beam needs a groove running along the top, side
and bottom so that epoxy or other glue may be
pumped in at one location and follows the groove all
the way around top, side and bottom. You would not
cut the cockpit floor open at all. Slide the I beam in
from the inspection ports and draw it back into the
correct position with cords running from the front
and rear inspection ports to the beam.

I have not figured out how to pump in the glue yet.

Maybe drill small holes (hidden by the Pro-Grip)
through the cockpit floor lined up with the glue groove.

We can stick the camera in from the front inspection
ports and see what is up in the angled part of the top
of the CB case.

I am also thinking of a longitudinal plank which
has  a fairly rigid polygon to fit up into that
angled section. Draw the plank up against the
underside of the cockpit floor and glue it there
transferring loads from the top of the CB case
to the cockpit floor.

Neither fix needs to add much weight and the
added weight is in a good location.

Regards,

Gil