Sealants

[henry]

Hi all

I've been restoring caravans for a living for 2 years now the main part of my time is taken up doing damp repairs and resealing I've always used a product called seamseal cv wich is a non drying bedding sealant I usually spend more time cleaning the stuff up after application than actually applying it
So I thaught I would order a box of sikaflex 512 last week as I believed it was a factory sealant that would partially cure on contact with air but stay wet under the trim and be easier to clean up everyone raves about the stuff on the Internet the price has always put me off in the past but I thaught if it's a better product and saves time it may be worth it
It turned out when I did a test spot on the bench that it totally cured like rubber not the right stuff at all the labelling In my opinion is totally deceiving it says caravan sealant on the tube
This morning I phoned sika's tech advice guy he informed me they no longer make a butyl based sealant they don't make a sealant fit for this purpose and sikaflex 512 is not intended for seating the joins in caravan skins
So I wonder what kind of caravan sealing sikaflex 512 is intended for? I am confused and out of pocket
Sorry for this little rant but I believe this information will be usefull to others

I will keep you updated on the search for the perfect sealant

Gary

[Brian M]

Thanks for these comments Gary, I will make some enquiries myself, as I have been recommending Sikaflex to those who ask me what to use.

I recall reading somewhere that repairers had stopped stocking Sikaflex due to its relatively short shelf life that was costing them money in expired tubes of the stuff.

[henry]

Hi Brian
When you resealed your safari did you use sikaflex? If so did it dry completely? I'm just wondering if they have recently changed the stuff)?

Oleary motorhomes I know have stopped stocking it I'm not sure why but I will be asking them

[oliver1]

For what it is worth, although I have never used it on a caravan I used to regularly use Lifecaulk (by Boatlife) on one of my previous yachts, which I feel sure is a more demanding environment. This is a polysulphide sealant and, although it is at the high end of the price range, when nothing less will do it is certainly a good one to go for. I would confidently expect it to be superb for use on a caravan.

boatlife.com/caulks-sealants/ This appears to be a US website, but I used to regularly buy it from yacht chandlers in the UK.

The instructions for use are most impressive. In effect, preferably apply to clean dry surfaces, if necessary apply to reasonably clean damp surfaces, in emergency can even be applied underwater!!!

Others assure me that it never sets hard, and certainly in my experience I never found it to do so.

One word of caution, ensure that you don't get it where it is not wanted, because it sticks to everything - voraciously!

There are of course other polysulphide sealants available; I merely recommend considering Lifecaulk because in a different (and more demanding) field it is one that I used to use regularly.

I see that another product from the same manufacturer, Life Seal, is currently available in the UK via an eBay site, at an arm-and-a-leg price: www.ebay.co.uk/itm/like/161127412086?clk_rvr_id=543869988276&mt_id=635&crlp=1_262531&fitem=161127412086&linkin_id=8022901&kw=%7Bquery%7D&crdt=0&sortbid=13. Note however that this is not the same product; it is described as a polyurethane/silicon sealant, not a polysulphide, and I have no experience of using it.


Oliver

[henry]

Hi Oliver

Thank you for your reply I had a look at the site yesterday it looks like its worth a try I shall order a tube see how it performs and report back

Gary

[rastasafari]

hello, has anyone tried sikalastomer-710 butyl sealant. we need to remove and re-bed all trims on our safari, after reading your posts thought this may be worth a try.
jon

[franni]

i spoke to a sikaflex technical man yesterday and he recommended sikaflex 212FC. that is made for busses trailers and caravans. the only negative for us is that you can only use acrylic paint over it and we want to use oil based enamel.
that was an australian tech adviser but i suppose it would be the same anywhere
cheers
franni