Recaulking teak deck

duncan99210

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Winter in Falmouth, summer on board Rampage.
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The mastic between the bits of teak in the cockpit has finally given up the struggle and is now sticky and disintegrating. This means that we'll have to dig the old stuff out and replace it.

Any advice on how to get the old stuff out without wrecking the teak strips?

When the old stuff is out, which is the best stuff to use to replace it?

Any tips on techniques to make getting the new mastic in and properly finished off?

All this is, thankfully, cosmetic as the 'decking' is only a thin layer stuck onto the cockpit, so no water ingress issues to resolve!
 
Some of the multi tools such as fein have different size mini chisels specifically for this kind of job - failing that make your own bent scraper and do it that way - that'll be fun ;)

There may even be a router attachment but others may be able to advise on that - how comprehensive is your too kit ?

PS: altho; your deck is cosmetic water will still find a way under the planks and could cause problems I should imagine
 
I had this done on my boat. The chap painstakingly raked and chiselled all the old sealant out from between the teak planks on my Nauticat 43, cleaned up the resulting gaps, primed them and sealed them with a product called SABA Seal One Fast. Seems to have worked really well - now problems, so I can recommend it. The Marine Ware distributors were excellent and came and inspected my decks to ensure it was the right product. I have no connection with the product or company etc etc...

I have the data sheets, application method and coverage calculator which I can email you if you PM me - I can't attach due to the pathetic file size allowance!

Piers
 
The mastic between the bits of teak in the cockpit has finally given up the struggle and is now sticky and disintegrating. This means that we'll have to dig the old stuff out and replace it.

Any advice on how to get the old stuff out without wrecking the teak strips?

When the old stuff is out, which is the best stuff to use to replace it?

Any tips on techniques to make getting the new mastic in and properly finished off?

All this is, thankfully, cosmetic as the 'decking' is only a thin layer stuck onto the cockpit, so no water ingress issues to resolve!

Just done a section on my 37 cockpit seats where there is a dip which holds water. Fortunately most of the old sealant had gone, but I cut out the bits that were left in with a craft knife. Masked the edges of the strips and caulked with the Saba equivalent of Sikaflex. You don't use very much so not a lot of difference in cost if you can only get Sika. Shaped a stick to exact size of the width of the seam and ran it down the caulking to level with the planks. Stripped the tape off (messy job wear gloves and don't do it if there is any wind). 24 hours later hard enough to sand and clean up the little bits that go over. Invisible repair. very satisfying and you will deserve the beer at the end when you admire your handiwork.
 
All good advice above. I used a craft knife along the seams and then a small chisel to lift the old mastic. Carefull if you use a knife not to leave 'loose slivers' of wood along the seams.
Also use a breaker tape along the bottom of the seam.... the mastic is supposed to adhere to the sides of the teak and the mastic should be able to slide ove rthe bottom as it expands and contracts. Acetone the edges of the teak and prime so as to get good adhesion.
Its only a small area so you should be able to make a really good job without too much agony. Ohh and warm mastic in hot water before use.
 
Echo everything so far. You are lucky to be doing a small area - I did a 46ft boat decks and coachroof.

One thing to add; if you use bond breaker tape buy the size smaller than think you need. If the gap is 5mm buy 4mm, if it is 4mm buy 3mm. Bond breaker tape is fiddly to lay.

I used Saba because of the quantity needed. In your case it is probably easier to access Sikaflex.

Good luck.
 
Don't think it is necessary to use breaker tape as the teak does not move. It is a veneer, about 3mm thick glued to a plywood substrate which is then vacuum bagged onto the grp. The seams are therefore not very deep or wide. It seems to work well. After 12 years the only bit that needed doing on mine is the part of the aft seat where water pools, and then for some reason, only one side. The rest of the seats and floor are still sound.
 
Yes, on reflection, I think that breaker tape is overkill for this sort of job.

Yes, for small repairs but I understand it is crucial for large areas. I'm about to do a 47 foot boat after having a lot of repair work done this spring/summer in Portugal.

One other point, I thnk you will find that the professionals leave the caulking to dry for 5 to 7 days before they cut away the excess and sand.

Also, avoid putting the caulking down in hot weather (N/A I know if you are about to do it in the UK). If you do it in the sun the caulking will bubble as it cures leaving nice air holes when you sand it down.

Bob
 
Yes, for small repairs but I understand it is crucial for large areas. I'm about to do a 47 foot boat after having a lot of repair work done this spring/summer in Portugal.

It is not the area that is the determining factor but the method of construction. If you have more traditional planks of between 6-12mm thick, then the seams are wider and deeper plus critically the wood will expand and contract, so you want to keep the caulking separate from the substrate. That is the purpose of the breaker tape.

Duncan's and my boats are Bavarias where the teak is a decorative veneer ply and the caulking is also decorative. The teak is so thin expansion and contraction is minimal and at the same rate as the ply to which it is bonded - which is also minimal. So filling the seam completely is satisfactory. As it is shallow (less than 3mm) bubbles are not usually a problem, and being moisture curing it will set enough to sand in a day. With deeper seams the cure takes longer, and if you sand too early you run the risk of pulling the caulking out of the seam.

Just remembered, you have a Bavaria. If yours is teak on ply the same will apply to you. You can check by scraping a seam out. If it is 3mm and then ply you can adopt the same technique as I described. However, it is a massive job to remove all the old caulking, particularly without damaging the veneers.
 
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Bond breaker tape is fairly pricey.

In the spirit of PBO, some bloke mentioned to me that he had used cassette tape (available from any car boot sale!). Mind you, I would have thought it would be a tad boisterous when trying to lay it with any sort of breeze about.
 
Sorry to drag an old post up, this is something I will be doing this winter as and when it cools down. Duncan, did you not use an electric tool for the removal of the old stuff? If so, what was it? I sat on the finished job, and it looked good as new.
 
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