Interprotect 2000E vs. Petit Protect 4700/4701 barrier coat

[horsemel]

I am going to have the bottom of Blue Moon stripped this winter, repair some blisters and barrier coat the hull.  It sounds like all of this is more pain in the a@# than difficult.  I intend to do the barrier coat myself.  It seems that the two most mentioned are the Interprotect 2000E and the Petit Protect 4700/4701.  In reading the labels I get the impression they both claim to do the job.  What is your experience with the two products?  Is one easier to use?  Does one build to the correct thickness in fewer coats?  Does one work better with VC17 bottom paint than the other?
Mark Mueller

[sailingdream]

I had my bottom stripped and 5 layers of 2000E put on myself. Stuff rolls on very easy, just like paint. this was done back in 2007 and have been using VC17 since than.

cant comment on petit.

[Ken Juul]

I would ask the paint manufacturers to make sure there are no chemical interactions between the barrier coat and the VC17 that you would need to be careful about.

[karista]

You may also want to consider VC-TAR which was specifically designed for VC Paint. It is a 2 part Tar based epoxy, somewhat pricey, but has held up exceptionally well on my boat. We applied 5 coats!

[tonywright]

Interprotect 2000 and VC17 is the standard method at my club. That is what I had on my previous boat.  Seems to be what all the local service providers recommend. It must be on a couple of hundred boats here at least.

When you apply the Interprotect, make sure that the hull is ultra-clean. Any spot of grease, wax etc will cause the IP to blister in that area later.  Also get the finish as smooth as you can. The PO had used a roller on mine, and left an "orange-peel" type of finish. I decided to sand it smooth to gain an extra 0.1 knot . If you are going to do this, better to do it BEFORE you put any VC17 on it. Sanding off oxidized copper is very, very messy. Better to get it smooth with a very smooth roller!

Tony

[horsemel]

Thanks a lot for the responses.  This should make the decision a lot easier.  I will also ask about compatibility with vc17, but sounds ok on the 2000 side of things.  One last question which came to me later, how do you do the area on the hull covered by the cradle pads?  Is there some easy answer to this I'm not seeing?
Mark Mueller

[tonywright]

You use jack stands to take the weight in a slightly different position, and then back off and remove the cradle pads. It will depend on how many jack stands you can get your hands on. Just make sure that they are chained together since you will be working underneath the boat...

Tony

[Ted Pounds]

I think most boatyards will require one of their guys to move the jack-stands.  True story:  A number of years back a boat owner at the the yard where I kept my boat moved his own stands.  One of the yard guys noticed he had removed all the stands one side.    Fortunately the boat had a slight lean into the stands still left (and the wind was from the right direction).  Needless to say they quickly replaced the missing stands.  I don't think it was C34.

[pablosgirl]

Hi Mark,

I have applied the Interlux E2000 system on two boats.  The first was 16 years ago when I pulled our Hunter 26.5 for a bottom job and discovered it had the "pox", literally thousands of pencil diameter blisters in the gel-coat all over the hull.  Had to strip all the gel-coat off the hull bellow the water line.  Took three, 12 hour days in the hot Texas sun using 36 grit sanding wheel.  I let the hull dry for two months before I applied fairing epoxy followed by 2 coats of Interlux Interprotect 1000 to seal the fiberglass, then 8 coats of Interprotect 2000E to replace the gel-coat.  I kept applying the 2000E until it was the same thickness as the remaining gel-coat above the waterline.  I then applied Petit Trinidad bottom paint over that.  When I pulled the boat two years ago there were only a handful of blisters present, and I just treated those locally with West System epoxy and their barrier filler.

Earlier this year we purchased c34 hull 551 and found some minor gel-coat blisters in a few places at the water line when we went to paint the bottom.  The Hull had been painted with 4 layers of Interlux Interprotect 2000E when it was commissioned in 1988. Evidently, the barrier coat and bottom paint were not painted high enough on the hull and the gel-coat absorbed some water where the waterline rose over the paint line.  The PO (the second owner) had the boat painted last year and had the marine yard raise the paint line and apply the petit barrier coat system to the bottom to treat the waterline blisters and then two coats of bottom paint.  Unfortunately, the marine yard did not remove all the old coats of bottom paint down to the original Interlux barrier coat epoxy!  The Petit barrier coat paint reacted with the old bottom paint and started to flack off (it looked like alligator skin).  The instructions for both the Interlux and Petit barrier paint products clearly state that you cannot apply these over single part epoxy bottom paint.  In order to get a sound surface for the new bottom paint to adhere to, we had to have all of the coats of bottom paint and petit barrier paint sanded off down to the Interlux Interprotect 2000E.  This was quit a job!  Next we applied four coats of Interlux Interprotect 2000E alternating between the gray and white colors so we would know if we sanded off to much in subsequent bottom jobs( the last coat was white and the bottom paint blue).  Then we applied two coats of petit Trinidad SR to the bottom ( I really like this paint!  I get a minimum of 5 years out of this paint with regular scrubbing).  

I don't have any experience with the Petit product, but I can highly recommend the Interlux product.  It is easy to apply with either a roller or brush.  I found that using a roller gets the most even coverage of paint.  I found that to get the smoothest finish (without spraying the product) was to roll it on and "tip" the fresh coat with a good quality brush.  This will minimize the "orange peal" or stipple effect of the roller.  This is the same technique used to apply topside epoxy paint over gel-coat.  I found a great on-line source for the Interlux paint at www.wholesalemarine.com for $68/Gal with free shipping!  I found that 1 gallon will cover the entire bottom (hull, keel, and rudder) of a C34 with some left over.  So I ended up with 4 1/2 coats with 4 gallons of paint.  If you have any question, please email me

Paul & Cyndi Shields

[horsemel]

Thanks for the information.  Paul I checked out wholesale marine's pricing and it is certainly much lower the WM by about a third.
Mark Mueller