2 pack epoxy

[jddevel]

Although I would have preferred to have my hull Zinga treated as Debdale are quoting end of 2019 next available I am now considering having my sailaway grit blasted locally (Cornwall) by a mobile engineer and replacing the Intertuf 16 with 2 pack epoxy. Reading previous threads  Hempel Hempadur 15130 Coal Tar Epoxy, Sigmacover 300 or  Dacrylate seem to be the recommended D.I.Y. products to go for. Is there a forum preference or any comments  please.

[Tony Brooks]

If you are having it grit blasted why not apply Zinga or a similar product compatible with the two pack/ Zinga is not much more than a zinc rich paint like Galvafroid and others. I think Debdale do hopt, molten zinc spraying and that is not Zinga although they may also apply Zinga if the customer can't afford the hot zinc process, I do not know.

[Dr Bob]

Is a coal tar epoxy a DIY product? High performance is obtained when applied to grit blasted steel.....straight after blasting. In high humidity environments leaving steel more than a few hours will see surface oxidation and reduction in performance. Temp, dew point, thickness all important. Best performance when sprayed to the right thickness. Airless spray kit is not usually DIY. Apologies if you are experienced in these type of coatings.

If you are going to the cost of blasting, I too like Tony would put some sort of zinc rich primer. In the old days a can of red lead primer was the ultimate. Nothing has really replaced it.

[jddevel]

It`s not the cost of the Zinga treatment ( not wishing to appear pretentious) it`s I don`t want to wait until November 2019 which as stated is the first available slot, as of earlier in the week, that Debdale can fit me in. Also  to rephrase my question.  Is there a 2 pack epoxy that can be applied D.I.Y as that appears to be the forums recommendation for hull treatment if Zinga is not available. As a leisure craft in a marina environment for a good deal of time, traditional blacking and its problem with water born solvents seems according to forum members can be problematic.

 

[Drayke]

Can’t remember what two pack I used, still have a tin somewhere, but back in 2008 had sides of hull shot blasted then applied two pack on to the bare steel, put on five coats using roller and brush. Had boat out again in 2014, so put two more coats on. So yes you can do it yourself.

Edited June 17, 2017 by F DRAYKE

[noddyboater]

I did a diy blasting job on my boat, cabin and hull back in '99. A scaffolding frame and tarpaulin tent was made, about 20' long and I hired the gear and blasted it myself over 5 days. Each section was primed with Dacrylate 2pack epoxy grey and then 2 coats of epoxy black on the hull to finish. It's actually only been blacked twice since then but the paint is always in amazingly good condition when she does come out. Dacrylate certainly isn't the most expensive product on the market but on well prepared steel you can't really go wrong. 

[blackrose]

Jotamastic 87 

I've got 2 coats of Jotamastic 87 with aluminium + 2 coats of Jotamastic 87 black.

http://www.jotun.com/Datasheets/Download?url=%2FTDS%2FTDS__523__Jotamastic 87 Aluminium__Euk__GB.pdf

I got it gritblasted and did the painting myself. It's fairly easy to use. If you decide to use it and want any advice send me a PM.

Edited June 18, 2017 by blackrose

[Tony Brooks]

I don't want to labour the point but what Debdale offer is NOT Zinger. Zinger is a PAINT that can and has been DIY applied. You do not seem to have grasped this. You can apply Zinger yourself.

It is very unlikely that you can HOT ZINC SPRAY (as done at Debdale) yourself because of getting hold of the kit.

[Bloomsberry]

9 hours ago, jddevel said:

It`s not the cost of the Zinga treatment ( not wishing to appear pretentious) it`s I don`t want to wait until November 2019 which as stated is the first available slot, as of earlier in the week, that Debdale can fit me in. Also  to rephrase my question.  Is there a 2 pack epoxy that can be applied D.I.Y as that appears to be the forums recommendation for hull treatment if Zinga is not available. As a leisure craft in a marina environment for a good deal of time, traditional blacking and its problem with water born solvents seems according to forum members can be problematic.

 

I did an experimental DIY epoxy job on my boat last year, preped it using a rotary blaster tool in a drill and used international interzone as the epoxy. Prepping took a very long time but I stuck at it and managed to do the waterline, welding seems and pitted areas in 3 days. A year later and  it all appears to be in place. The boat is coming out next year to check on the blacking and treat other areas that I hadn't had time for previously.

[jddevel]

29 minutes ago, Tony Brooks said:

 

I don't want to labour the point but what Debdale offer is NOT Zinger. Zinger is a PAINT that can and has been DIY applied. You do not seem to have grasped this. You can apply Zinger yourself.

It is very unlikely that you can HOT ZINC SPRAY (as done at Debdale) yourself because of getting hold of the kit.

 

Thank you Tony. It was the hot zinc I was looking at. I have had a quote for me to apply a DIY from a company but thought the hot method seemed preferable.

Regarding the other advice I am grateful and will way up my possibilities. The fundamental problem is I`m out in the open in what can be a windy location next to a farm field in Cornwall with all the uncontrollable movement in that field. Spraying/harvesting etc. Plus the vagaries of the English weather. How do I successfully cover a 57 foot craft and avoid contamination and allow access by the shotblaster -he has said he can use air only to assist the drying after blasting process (quoted £150 plus £50 per hour) plus ensure I`ve completed the  laying on within the 4 hour window.

[peterboat]

42 minutes ago, Tony Brooks said:

I don't want to labour the point but what Debdale offer is NOT Zinger. Zinger is a PAINT that can and has been DIY applied. You do not seem to have grasped this. You can apply Zinger yourself.

It is very unlikely that you can HOT ZINC SPRAY (as done at Debdale) yourself because of getting hold of the kit.

I applied the zinger myself 2 coats its not really paint though its 90 odd% zinc solids in a thick sticky liquid very heavy and I mean heavy!! dries very fast and is tough

[jddevel]

Thank you Peter we have "corresponded" on this previously. However I believe you both had your boat in a dry dock and had easy access to the base plate. My boat sits on 2 high railway sleepers so unlike yourself I think access to the base plate will be difficult. I realize that many say don`t worry about the base plate but if I`m doing it may as well try and do the best possible although I feel I may well have to settle for just what is possible.

[Bee]

Mine is painted with Sigmacover, probably 300 but I can't remember offhand, all done with roller and brush. Just have a read of the tech spec as it may have a recommendation for a Zinc or Aluminium primer and you might even find that it is surface tolerant. Be careful not to mix too much at one go as it will start to go off on a hot day and its too expensive to waste.

If you cannot get to the underneath to remove the Intertuf then I would crawl under the thing and roller another couple of coats of Intertuf on it,

[Dr Bob]

2 hours ago, jddevel said:

Thank you Tony. It was the hot zinc I was looking at. I have had a quote for me to apply a DIY from a company but thought the hot method seemed preferable.

Regarding the other advice I am grateful and will way up my possibilities. The fundamental problem is I`m out in the open in what can be a windy location next to a farm field in Cornwall with all the uncontrollable movement in that field. Spraying/harvesting etc. Plus the vagaries of the English weather. How do I successfully cover a 57 foot craft and avoid contamination and allow access by the shotblaster -he has said he can use air only to assist the drying after blasting process (quoted £150 plus £50 per hour) plus ensure I`ve completed the  laying on within the 4 hour window.

'Industrial' painting is a skilled job - and I would consider this a skilled job. If you are doing it yourself with no experience of these type of coatings then make sure you research them well. Read the instructions you get with the coatings and follow them to the letter. This isnt the sort of thing you do having thrown away the manual.

Given your location and conditions, here are some of my thoughts.

Coatings to protect steel work in 2 ways. One is to stop water and air getting to the metal surface. The second is to add something to passivate the surface ie zinc or lead.

The first is done with a good barrier coating (ie epoxy with or without coal tar). It is strong enough to not crack etc....but it has to be applied to a 'perfect' surface. If not then with age, the bond between the coating and steel will start to fail and then if there is a slight crack allowing water/air in to the substrate, then that water will then force the coating/steel bond apart causing rust to spread. Good adhesion is therefore paramount. You have quoted a 4 hour window which I would agree with after which time the blasted steel will develop a rust bloom which will shorten the life of the coating. You therefore need to get the first coat on quickly. The second coat is not so important for adhesion as it should stick to the first - if you follow the instructions on the can. This says it is not a one person job. Assuming it is a 2 pack system, have one person mixing and two people applying. That way you can keep up with the blasting.

The next important thing is curing. 2 pack paints cure by the reaction of the 2 parts via a chemical reaction. To get full performance you need 'full' curing. That will not happen unless the temp is higher than 15deg C. Do it on a warm day! Temperature is also important to make sure the surface is ok. You have to be 3-4 deg above the dew point, otherwise the 'clean' metal surface will have condensation on it which will reduce the adhesion and hence reduce lifetime. Dew point is measured by a wet and dry thermometer. At a pinch you can get away with a weather forecast but in practise paint it no earlier than late morning or preferably in the afternoon when the ambient temp should be much higher than the dew point. Do it on a dry day.

Linked to curing is thickness. These coatings contain solvents and are designed to be put on at a specific thickness. If too thick then solvent can be trapped which will reduce cure and lead to shorter lifetime. Too much sunshine (or wind) can cause solvents to evaporate too quickly and so cause crocodiling on the surface of the coating which again is bad. Watch out if one side of the boat is in full sun and the other in full shade. Painting the underside will be a real pig. Potentially cold and damp, limited access to get the thickness right.

If it was me I would get a professional to do it. If you have to do it yourself, find a few others to help, use an easy to apply primer - one that can be applied easily, and if possible use the belt and braces approach of a passivating primer followed by  2 pack top coats - AND FOLLOW THE MANUFACTURERS INSTRUCTIONS TO THE LETTER.

As shown in posts above, others have been able to do this themselves but it is not easy to get 10 year performance unless these coatings are applied properly.

Edited June 18, 2017 by Dr Bob
additions

[ditchcrawler]

When we did this offshore the blasters would spend all day  blasting off the old paint, muck,corrosion etc. Next morning they would quickly blast it again to remove the ginger "rust" that had occurred over night. then if the steel temperature, air temperature and dew point were all OK the "Paint Inspector" would let them apply the first coat of paint with airless spray. While they were painting the "paint Inspector" would measure the wet film thickness of the paint and also keep checking weather conditions.

The paint Inspector was not employed by the painting contractor.

[Dr Bob]

1 hour ago, ditchcrawler said:

When we did this offshore the blasters would spend all day  blasting off the old paint, muck,corrosion etc. Next morning they would quickly blast it again to remove the ginger "rust" that had occurred over night. then if the steel temperature, air temperature and dew point were all OK the "Paint Inspector" would let them apply the first coat of paint with airless spray. While they were painting the "paint Inspector" would measure the wet film thickness of the paint and also keep checking weather conditions.

The paint Inspector was not employed by the painting contractor.

......and these guys knew what they were doing.....and the coatings didnt always last as long as they were predicted to do (prediction via lab prepared samples). Painting splash zones was never easy and you could never get that 'perfect' preparation.

[Giant]

We have four coats of Hempel 15130 on our hull. It was no problem to apply DIY with big rollers.

Be aware that it does quickly turn from a gloss black to a chalky grey. If you want a gloss finish you'd need to apply some top coat.

[jddevel]

4 hours ago, Dr Bob said:

Industrial' painting is a skilled job - and I would consider this a skilled job. If you are doing it yourself with no experience of these type of coatings then make sure you research them well. Read the instructions you get with the coatings and follow them to the letter. This isnt the sort of thing you do having thrown away the manual

I appreciate your comments Dr Bob. The dilemma I face is that the availability of the "professional" to complete the work (Debdale 2019 others at least 12 months ) means that I`ve either to resort to continuing with the existing product (Intertuf16) which has simply had a "flash" coat as an initial barrier and from what I read on the forum will probably readily decay in the marina or with sufficient labour DIY. Recognizing a problem is one thing providing a possible solution another. What under the circumstances do you suggest?

[jddevel]

Anyone used this product? http://www.zrcworldwide.com/products/zrc-cold-galvanizing-compound

[Robbo]

5 minutes ago, jddevel said:

Anyone used this product? http://www.zrcworldwide.com/products/zrc-cold-galvanizing-compound

Comparison sheet with Zinga (by Zinga) http://www.zinga-uk.com/uploads/Tech_sheet_06___Zinga_vs_ZRC.pdf

[jddevel]

Thanks Robbo. Zinga obviously the better product.

[Robbo]

Found this which may be of use; http://www.dtic.mil/get-tr-doc/pdf?AD=ADA508873

[Dr Bob]

1 hour ago, jddevel said:

I appreciate your comments Dr Bob. The dilemma I face is that the availability of the "professional" to complete the work (Debdale 2019 others at least 12 months ) means that I`ve either to resort to continuing with the existing product (Intertuf16) which has simply had a "flash" coat as an initial barrier and from what I read on the forum will probably readily decay in the marina or with sufficient labour DIY. Recognizing a problem is one thing providing a possible solution another. What under the circumstances do you suggest?

My experience is fro 10 years ago so not up to date with new products BUT these have not changed in their surface prep requirements and chemistry. The chemistry is still the same.

First you need to decide if you want a high performance 2 pack coating system or use the traditional blacking. We've just bought a 15 year old nb with little corrosion despite being blacked throughout its life. Lifting out every 2 years and blacking can be costed over a 10 year period.

The cost of a 2 pack system can be costed over a 10 year period and no extra coating assuming 10 years performance but only if applied properly. Dont forget you will need to be lifted out now and again even with this system to do stuff....and these boats pick up a lot of canal life. If you cant get it proffessionally done then maybe factor a lower life time until recoating needed. My experience with a number of paint jobs (Refinery tank roofs, refinerly tank internals, offshore platforms etc..) says that it even the professionals dont get it right. 

I would very much prefer the high performance systems but only if I could get someone to do it. If it is 12 months waiting then I think I would wait until next time and book it now. If you really want to do it yourself, get a few of you together to do it, ring up one of the better paint suppliers viz Jotun, Hempel etc and speak to them to get their recommendation of the best combination of surface prep, primer and top coats, and how to apply it.

All the best.

[chubby]

My thoughts 

Completly inexperienced in such hull protection so my suggestion is not a technical one as such .

If paying Debdale to carry out your preferred method is no problem and that method is the one you think best for your boat long term would it be worth considering just getting the boat blacked in bitumen DIY , putting as many coats as possible over and over whilst the boat is being fitted out . Get it in the water , go and enjoy it and in the meantime book Debdale , pay the deposit and relax knowing that what you have applied to the boat is temporary and ( i think ?) largely sufficient until Debdale can do it ? 

Just a thought that will get you on the water and you will also have peace of mind knowing that your preferred option is booked? 

No headaches trying to figure out which 2 pack solution is best , no having to organise a " blacking party " to get the stuff on asap , bitumen will be very much cheaper & easier and in 2.5 years time you can have the expensive but probable best solution applied ? 

cheers

Edited June 19, 2017 by chubby