I would like to get some opinions on whether I should remove partially
cured epoxy in one large area of my deck.

Due to my failure to follow instruction in mixing epoxy and failure to
do a test batch before using a new type of hardener, I had not
thoroughly mixed the epoxy long enough when I installed the core
material onto the deck. The result is that the epoxy cures very very
slowly:

- After one day, I felt that the epoxy was still wet.

- After three days, I still could use my thumb to dent the epoxy.

- After ten days (today), it is solid enough that I cannot use my
thumb to dent it; but I still can use my finger nail to dent its
surface. And I definitely cannot sand it yet.

What should I do?

Should I wait another week or so to see if it may completely cure? I
can afford to wait because I can do something else while I wait; but I
am not sure if the epoxy will be strong enough even if it is seemingly
cured.

Should I remove everything and start this over? Unfortunately, this
will be very labor intensive to remove the partially cured epoxy.

The epoxy is from MAS and the hardener is MAS slow hardener. The brand
name may or may not matter.

Jay Chan

Assuming the curing temperatures are above 60 degrees and it is still
rubbery, you are hosed, it will never become hard and will get sticky
and nasty in hot weather... Plan on grinding it away... Consider a wire
brush mounted on a healthy drill motor (1/2") and lots of elbow
grease...
MAS is a fine product, I went through a couple of gallons on the past
month when I ran low on WEST...
denny - who has had every problem possible with epoxy...

Denny wrote:

Assuming the curing temperatures are above 60 degrees and it is still
rubbery, you are hosed, it will never become hard and will get sticky
and nasty in hot weather... Plan on grinding it away... Consider a wire
brush mounted on a healthy drill motor (1/2") and lots of elbow
grease...
MAS is a fine product, I went through a couple of gallons on the past
month when I ran low on WEST...
denny - who has had every problem possible with epoxy...


It's just a gummy mess, but it has to cove off if there are any further
layers on top of it.

A scraper used like a draw knife will work better.
Clean more area quicker.

In the end, if this was supposed to be the last layer, (once cleaned!)
you will probably want to add another layer - just to get the surface back.

Best of luck...

Richard

Denny wrote:
Assuming the curing temperatures are above 60 degrees and it is still
rubbery, you are hosed, it will never become hard and will get sticky
and nasty in hot weather... Plan on grinding it away... Consider a wire
brush mounted on a healthy drill motor (1/2") and lots of elbow
grease...
MAS is a fine product, I went through a couple of gallons on the past
month when I ran low on WEST...
denny - who has had every problem possible with epoxy...

The temperature is well over 60. The area is under the sun and is
covered with a boat cover, and the area is really really hot inside the
boat cover. Therefore, temperature should not have anything to do with
this problem. In other words, the epoxy is really in trouble, or I
should say "I am really in trouble".

I don't think there is anything wrong with MAS. This is just that
their Slow Hardener seems to be more sensitive to mixing error (their
Medium Hardener is more forgiving). I have been able to get away with
mixing not long enough using their Medium Hardener and still get epoxy
cured just fine. Unfortunately, when I switched to their Slow
Hardener, I forgot to do a test batch first, and I will have to suffer
from my own error.

Oh well...

Jay Chan

@#@

It most definitely has to come off. It will never cure properly. Get
yourself an small side grinder everyone makes
one now, get the rubber backing plate attachment and use very coarse open
coat sanding disc 10-60 grit it removes rubbery material fast. Epoxy is
notorious for ruining cutting tools and clogging sand paper good luck

Ray

wrote in message
oups.com...
I would like to get some opinions on whether I should remove partially
cured epoxy in one large area of my deck.

Due to my failure to follow instruction in mixing epoxy and failure to
do a test batch before using a new type of hardener, I had not
thoroughly mixed the epoxy long enough when I installed the core
material onto the deck. The result is that the epoxy cures very very
slowly:

- After one day, I felt that the epoxy was still wet.

- After three days, I still could use my thumb to dent the epoxy.

- After ten days (today), it is solid enough that I cannot use my
thumb to dent it; but I still can use my finger nail to dent its
surface. And I definitely cannot sand it yet.

What should I do?

Should I wait another week or so to see if it may completely cure? I
can afford to wait because I can do something else while I wait; but I
am not sure if the epoxy will be strong enough even if it is seemingly
cured.

Should I remove everything and start this over? Unfortunately, this
will be very labor intensive to remove the partially cured epoxy.

The epoxy is from MAS and the hardener is MAS slow hardener. The brand
name may or may not matter.

Jay Chan

Thanks for telling me which tools to use to remove the uncured epoxy.

What's a "side grinder"? Is it the same as a surface grinder that
another newsgroup member has suggested? I probably will go easy with
using power tools; the reason is that the area underneat the uncured
epoxy is just a thin layer of the inner skin of the cored deck. I
probably want to stick with hand tool such as a green pad, a wire
brush, a paint scraper, and white-vinegar.

Jay Chan


Raynaud wrote:
@#@

It most definitely has to come off. It will never cure properly. Get
yourself an small side grinder everyone makes
one now, get the rubber backing plate attachment and use very coarse open
coat sanding disc 10-60 grit it removes rubbery material fast. Epoxy is
notorious for ruining cutting tools and clogging sand paper good luck

Ray

wrote in message
oups.com...
I would like to get some opinions on whether I should remove partially
cured epoxy in one large area of my deck.

Due to my failure to follow instruction in mixing epoxy and failure to
do a test batch before using a new type of hardener, I had not
thoroughly mixed the epoxy long enough when I installed the core
material onto the deck. The result is that the epoxy cures very very
slowly:

- After one day, I felt that the epoxy was still wet.

- After three days, I still could use my thumb to dent the epoxy.

- After ten days (today), it is solid enough that I cannot use my
thumb to dent it; but I still can use my finger nail to dent its
surface. And I definitely cannot sand it yet.

What should I do?

Should I wait another week or so to see if it may completely cure? I
can afford to wait because I can do something else while I wait; but I
am not sure if the epoxy will be strong enough even if it is seemingly
cured.

Should I remove everything and start this over? Unfortunately, this
will be very labor intensive to remove the partially cured epoxy.

The epoxy is from MAS and the hardener is MAS slow hardener. The brand
name may or may not matter.

Jay Chan

Unlike the others, I'd vote for trying to get it to cure. A coating on a
deck is not structural, but just for sealing and abrasion resistance. I'd
try heating up the shop/deck/boat (whatever is easiest) to about 80 F or
even higher and keep it that way for a few days. It sounds to me like the
cure is progressing, but as others have mentioned, it may or may not cure to
the final hardness that you want. I don't think that's a big deal if it
gets reasonably hard and you put a couple of fresh coats of epoxy over the
top of it ...definitely easier than trying to remove it. Consider this:
Even your mostly-cured epoxy is harder and tougher than most plywood plies
that people are protecting with epoxy ...why not try to cure what you have
and then protect *it* with more layers of epoxy?

Brian D


wrote in message
oups.com...
I would like to get some opinions on whether I should remove partially
cured epoxy in one large area of my deck.

Due to my failure to follow instruction in mixing epoxy and failure to
do a test batch before using a new type of hardener, I had not
thoroughly mixed the epoxy long enough when I installed the core
material onto the deck. The result is that the epoxy cures very very
slowly:

- After one day, I felt that the epoxy was still wet.

- After three days, I still could use my thumb to dent the epoxy.

- After ten days (today), it is solid enough that I cannot use my
thumb to dent it; but I still can use my finger nail to dent its
surface. And I definitely cannot sand it yet.

What should I do?

Should I wait another week or so to see if it may completely cure? I
can afford to wait because I can do something else while I wait; but I
am not sure if the epoxy will be strong enough even if it is seemingly
cured.

Should I remove everything and start this over? Unfortunately, this
will be very labor intensive to remove the partially cured epoxy.

The epoxy is from MAS and the hardener is MAS slow hardener. The brand
name may or may not matter.

Jay Chan

Actually, the uncured epoxy is supposed to secure the core material on
the inner skin of the cored deck. Therefore, it is structural. I
check it this morning, and I find that the area is still bouncy. I
expect that the area should be rigid enough with the combo of the inner
skin, the epoxy, and the core material; but it is not. This means I
cannot expect it to provide any structural support as a deck is
supposed to do. That is not good.

On the other hand, you are right -- removing the uncured epoxy is going
to be a messy job. I think I will give it one more week to see if will
be cured by then -- hopefully.

Jay Chan


Brian D wrote:
Unlike the others, I'd vote for trying to get it to cure. A coating on a
deck is not structural, but just for sealing and abrasion resistance. I'd
try heating up the shop/deck/boat (whatever is easiest) to about 80 F or
even higher and keep it that way for a few days. It sounds to me like the
cure is progressing, but as others have mentioned, it may or may not cure to
the final hardness that you want. I don't think that's a big deal if it
gets reasonably hard and you put a couple of fresh coats of epoxy over the
top of it ...definitely easier than trying to remove it. Consider this:
Even your mostly-cured epoxy is harder and tougher than most plywood plies
that people are protecting with epoxy ...why not try to cure what you have
and then protect *it* with more layers of epoxy?

Brian D


wrote in message
oups.com...
I would like to get some opinions on whether I should remove partially
cured epoxy in one large area of my deck.

Due to my failure to follow instruction in mixing epoxy and failure to
do a test batch before using a new type of hardener, I had not
thoroughly mixed the epoxy long enough when I installed the core
material onto the deck. The result is that the epoxy cures very very
slowly:

- After one day, I felt that the epoxy was still wet.

- After three days, I still could use my thumb to dent the epoxy.

- After ten days (today), it is solid enough that I cannot use my
thumb to dent it; but I still can use my finger nail to dent its
surface. And I definitely cannot sand it yet.

What should I do?

Should I wait another week or so to see if it may completely cure? I
can afford to wait because I can do something else while I wait; but I
am not sure if the epoxy will be strong enough even if it is seemingly
cured.

Should I remove everything and start this over? Unfortunately, this
will be very labor intensive to remove the partially cured epoxy.

The epoxy is from MAS and the hardener is MAS slow hardener. The brand
name may or may not matter.

Jay Chan

Jay,
I'd say the epoxy has finally reached the 'green stage' . . . about 10 days
late, but better then never. True, you really can't *properly* sand it yet -
but it proves that the chemical reaction IS progressing. What a lot of
people don't realize is that because the epoxy 'curing' is an 'internal
conversion' chemical process {as opposed to the 'catalyst additive' of
polyester}, a actual 'FULL CURE' can take several months. It's a geometric
progression so that after about 72-hours {if everything is done 'per
instruction'} it doesn't matter to the typical user. Additionally, because
the reaction is rather temperature dependent it can be somewhat controlled.
That is sped up or slowed down to almost a 'hibernation' point . . . I've
used it as low as the mid 30's, which supposedly you can't do.

If time is NOT a problem, and the surface is horizontal {so there is no
slippage or 'curtaining'} I'd just wait. Especially as the weather is
warming up. When it gets to the point you can't dent it with a finger nail,
give it a couple of swipes with some sandpaper. If it still gums up, wait a
bit longer and use a 'regular nail' for scratch testing. Use the time to
make some small 'test batches' so you get comfortable with mixing {BE
THROUGH - this is the MOST prevalent cause of problems}and application.

When physically possible, sand and proceed, or sand and 'paint on' a thin
cover coat of unthickened fresh epoxy and continue the project.

If not this . . . then get yourself a stack of filter masks, a Tyvek suit, a
couple of Surform tools & extra blades, belt sander & 'Planer' belts, a
4-1/2in surface grinder, and have at it.!!

Regards & Good Luck,
Ron Magen
Backyard Boatshop
{PS - I understand that MAS is quite a bit over-priced for what you get . .
.. and it's formulated relatively close to where I live}
..
wrote in message
oups.com...
I would like to get some opinions on whether I should remove partially
cured epoxy in one large area of my deck.

Due to my failure to follow instruction in mixing epoxy and failure to
do a test batch before using a new type of hardener, I had not
thoroughly mixed the epoxy long enough when I installed the core
material onto the deck. The result is that the epoxy cures very very
slowly:

- After one day, I felt that the epoxy was still wet.

- After three days, I still could use my thumb to dent the epoxy.

- After ten days (today), it is solid enough that I cannot use my
thumb to dent it; but I still can use my finger nail to dent its
surface. And I definitely cannot sand it yet.

What should I do?

Should I wait another week or so to see if it may completely cure? I
can afford to wait because I can do something else while I wait; but I
am not sure if the epoxy will be strong enough even if it is seemingly
cured.

Should I remove everything and start this over? Unfortunately, this
will be very labor intensive to remove the partially cured epoxy.

The epoxy is from MAS and the hardener is MAS slow hardener. The brand
name may or may not matter.

Jay Chan

When I mix a pot of epoxy, and maybe this goes back to my painting days, I
generally mix it really well (scraping sides and bottom with square-tipped
mixing stick) then set it on the bench for a couple of minutes to 'kick'.
While I do that, I get rollers or brushed together, or wipe down the
'project', etcetera. Then I stir up the epoxy real well (again) and go
ahead with using it. I prefer that to just standing there and mixing for 3
minutes and I've never had a failed batch, even with mustard-pump measured
5:1 ratio epoxies (yikes!)

Brian


"Ron Magen" wrote in message
news:uo0kg.26606$X02.20217@trnddc02...
Jay,
I'd say the epoxy has finally reached the 'green stage' . . . about 10
days
late, but better then never. True, you really can't *properly* sand it
yet -
but it proves that the chemical reaction IS progressing. What a lot of
people don't realize is that because the epoxy 'curing' is an 'internal
conversion' chemical process {as opposed to the 'catalyst additive' of
polyester}, a actual 'FULL CURE' can take several months. It's a geometric
progression so that after about 72-hours {if everything is done 'per
instruction'} it doesn't matter to the typical user. Additionally, because
the reaction is rather temperature dependent it can be somewhat
controlled.
That is sped up or slowed down to almost a 'hibernation' point . . . I've
used it as low as the mid 30's, which supposedly you can't do.

If time is NOT a problem, and the surface is horizontal {so there is no
slippage or 'curtaining'} I'd just wait. Especially as the weather is
warming up. When it gets to the point you can't dent it with a finger
nail,
give it a couple of swipes with some sandpaper. If it still gums up, wait
a
bit longer and use a 'regular nail' for scratch testing. Use the time to
make some small 'test batches' so you get comfortable with mixing {BE
THROUGH - this is the MOST prevalent cause of problems}and application.

When physically possible, sand and proceed, or sand and 'paint on' a thin
cover coat of unthickened fresh epoxy and continue the project.

If not this . . . then get yourself a stack of filter masks, a Tyvek suit,
a
couple of Surform tools & extra blades, belt sander & 'Planer' belts, a
4-1/2in surface grinder, and have at it.!!

Regards & Good Luck,
Ron Magen
Backyard Boatshop
{PS - I understand that MAS is quite a bit over-priced for what you get .
.
. and it's formulated relatively close to where I live}
.
wrote in message
oups.com...
I would like to get some opinions on whether I should remove partially
cured epoxy in one large area of my deck.

Due to my failure to follow instruction in mixing epoxy and failure to
do a test batch before using a new type of hardener, I had not
thoroughly mixed the epoxy long enough when I installed the core
material onto the deck. The result is that the epoxy cures very very
slowly:

- After one day, I felt that the epoxy was still wet.

- After three days, I still could use my thumb to dent the epoxy.

- After ten days (today), it is solid enough that I cannot use my
thumb to dent it; but I still can use my finger nail to dent its
surface. And I definitely cannot sand it yet.

What should I do?

Should I wait another week or so to see if it may completely cure? I
can afford to wait because I can do something else while I wait; but I
am not sure if the epoxy will be strong enough even if it is seemingly
cured.

Should I remove everything and start this over? Unfortunately, this
will be very labor intensive to remove the partially cured epoxy.

The epoxy is from MAS and the hardener is MAS slow hardener. The brand
name may or may not matter.

Jay Chan