Masking Tape for Barrier Coat

[lancelot9898]

Does anyone have a suggestion for masking tape when putting on many layers of barrier coat epoxy(interprotect 2000e) on the bottom? Want to tape just once without removing the tape after each coat.

[sartorst]

A good brand of painters tape,I like to use a wide tape a little above the true line then come back with a 1/2 inch tape over that, makes taping the line easier ,and at the end of each run of tape fold it back on its self to leave a tab to pull when the time comes to pull it and when pulling it pull it right after the last coat, pull it back against its self,the last coat will have softened the previous coats ,now that will leave a hard edge,but the only other thing to do is move up a little and re- tape on the last coat that will soften the edge
Also when I use the re-tape method I'am only painting that upper line not an entire bottom coat to make it go fast and pull the tape quick

[brankin]

3M 233+ is an excellent tape but on the pricey side. You can also use the scotch blue tape (I don't remember the part number). What I do is stack the tape in layers according to how many coats of epoxy I am going to be applying. To save money, use 2" on the first layer and 3/4" on the rest. After each coat, pull off a layer of tape and at the end , you won't have the problem of the tape tearing apart because of the thickness of the epoxy.

[David M]

You have to remove the tape regardless of the type of tape before the Interlux 2000 completely cures. The epoxy will remain soft enough to remove the tape for the first couple of days. Given you can apply two coats per day of Interlux 2000, this still allows you to do more than one coat with one application of tape. I have done this with Interlux 2000 and it works.

[brankin]

Originally Posted by David M

You have to remove the tape regardless of the type of tape before the Interlux 2000 completely cures. The epoxy will remain soft enough to remove the tape for the first couple of days. Given you can apply two coats per day of Interlux 2000, this still allows you to do more than one coat with one application of tape. I have done this with Interlux 2000 and it works.

And if you are in south Florida in July with the sun beating down on the epoxy, it will get hard real quick and then you can have a mess on your hands. Or you can save a half a roll of tape and take your chances.

[David M]

Originally Posted by brankin

And if you are in south Florida in July with the sun beating down on the epoxy, it will get hard real quick and then you can have a mess on your hands. Or you can save a half a roll of tape and take your chances.

Which is why I said before the epoxy cures. Cure time will vary significantly with temperature.

You also have to apply coats of Interlux 2000 before it cures completely, so you get a chemical bond between coats. This means not skipping a day between coats.

[minaret]

Chemical bond time on 2000e is now six months. Skip all the days you want between coats. It used to be two weeks.

[barnakiel]

I use cheap tape and I re-tape every day. I do this because at least once we had issues removing the good&expensive 3M blue tape after a complete multi-day job - its very edge got amalgamated to the many now layers of paint.

b.

[delmarrey]

Myself,
I don't worry about taping. During the prep I sand up into the boot stripe and over lap the bottom edge of the boot stripe with the epoxy. After the epoxy cures sand the edge of the epoxy flush then tape off the edges of the boot stripe, lightly sand and repaint the boot stripe.

The barrier coat needs to be lightly sanded to put on the bottom paint and now the top edge is already done.

[minaret]

Originally Posted by delmarrey

Myself,
I don't worry about taping. During the prep I sand up into the boot stripe and over lap the bottom edge of the boot stripe with the epoxy. After the epoxy cures sand the edge of the epoxy flush then tape off the edges of the boot stripe, lightly sand and repaint the boot stripe.

The barrier coat needs to be lightly sanded to put on the bottom paint and now the top edge is already done.

If the barrier coat in question is 2000, it's better NOT to sand it. Catch a thumbprint phase chemical bond instead.


Doesn't your method lose the original waterline?

[delmarrey]

Originally Posted by minaret

If the barrier coat in question is 2000, it's better NOT to sand it. Catch a thumbprint phase chemical bond instead.


Doesn't your method lose the original waterline?

Not if you paint the boot stripe back on the same location.
Your only destroying the lower edge of the boot stripe. You know the width, so you remeasure the width, re-tape the bottom edge and paint it back on after you sand it flush.
Sanding the very top edge of the 2000 won't make any difference. The bottom paint will still stick.

[minaret]

Originally Posted by delmarrey

Not if you paint the boot stripe back on the same location.
Your only destroying the lower edge of the boot stripe. You know the width, so you remeasure the width, re-tape the bottom edge and paint it back on after you sand it flush.
Sanding the very top edge of the 2000 won't make any difference. The bottom paint will still stick.

If you wait till the 2000 is dry enough to sand you have lost the chemical bond window and now must sand the whole bottom. The width of the boot stripe is not a constant, you'd have to take a measurement every foot or so all the way around and then restrike the waterline. Lots of work. We do it that way often, but only because the blisters often go above the waterline a little ways. If there are no blisters above the waterline, we use multiple layers of tape. Usually do 6 coats, 2 per day, and pull tape each day, so tape 3 layers thick is good. Then before bottom paint the waterline gets moved up just a hair so there's no exposed grey barrier coat edge.

When I do this method I prefer a tick stick to measurements. I put a piece of tape about a foot long vertically every foot or so all the way around the waterline, closer together on sharp curves like under a counter, further apart amidships. Then I use an arbitrary length tick stick, often a 12" stir stick, and go around the boat transferring the bottom and top edge of the boot stripe as well as the waterline (if there is an accent stripe). The tick stick and tape obviously need to be longer than the distance you will be sanding up on to the hull. After sanding everything out you get out the same tick stick and transfer the marks back down. No measurement, quick and easy method. Guaranteed to work every time without getting out the laser level. I'm big on tick sticks for all sorts of stuff. Just do t lose the tick stick I between or you're screwed! Had it happen a lot when using stir sticks for tick sticks, some idiot comes along and goes "what's this stick with marks on it and SAVE written on the side? Think I'll use it to stir paint"!

[brankin]

Originally Posted by minaret

If you wait till the 2000 is dry enough to sand you have lost the chemical bond window and now must sand the whole bottom. The width of the boot stripe is not a constant, you'd have to take a measurement every foot or so all the way around and then restrike the waterline. Lots of work. We do it that way often, but only because the blisters often go above the waterline a little ways. If there are no blisters above the waterline, we use multiple layers of tape. Usually do 6 coats, 2 per day, and pull tape each day, so tape 3 layers thick is good. Then before bottom paint the waterline gets moved up just a hair so there's no exposed grey barrier coat edge.

This is the best way to do it. As usual, Minaret is right on the money.

[delmarrey]

All those layers of tape. That seems like a lot of work too. But I guess with 2000 what choice do you have. I think I would progress each layer about 1/16" so one doesn't end up with a hard edge (step) in the end.

[minaret]

I've tried both. I'd rather have one not so big hard edge, with the bottom paint line a hair above it, than six little hard edges. Looks wierd. Three layers of tape only takes a half hour, and you can use cheap one inch for the sacrificial layers, as others mentioned before.