Sikaflexxing

Discussion in 'Solar Power' started by Moodybrook, Jan 11, 2014.

  1. Moodybrook

    Moodybrook Funster

    Joined:
    Jul 7, 2013
    Messages:
    754
    Likes Received:
    628
    Location:
    Dumfries
    Following on from another funsters bitter experience with a Satellite dome coming off his roof :Eeek:
    That has somewhat dented my confidence about sticking on a Solar panel onto the overcab portion of my roof. I am generally quite knacky at the general fixing jobs though I say myself.
    However can some of you old salts pass on a few tips on the mystic art of applying Sikaflex 512 effectively. I have one tube and now I am considering purchasing a second as it is quite a big sod 1.590 x 790. I have the four corners, 2 x 530mm and 2 x 180 side plastic mounts.

    I am putting the 2 x 530 and one 180 on the leading edge to restrict wind flow underneath the panel.

    I was to put a fair amount of Sikaflex onto the mounts having "roughed up all contact surfaces" and on the designated place was to gently move it around to settle it into the gunge then clean up after I was happy that the "Eagle has landed".

    Do I need "activater" ? Is ambient temperature crucial ? Is their no replacing some good bolts ?

    Your comments (constructive) and advice will be appreciated. :Smile:
     
  2. SIFTA SAM

    SIFTA SAM Read Only Funster

    Joined:
    Jan 27, 2009
    Messages:
    454
    Likes Received:
    452
    Location:
    Leyland Lancs
    Look on line for the Sikaflex Technical Instructions for that adhesive for correct manufacturers instructions as I did. (see below)
    From using that product to attach my solar-panel (no screws) I do not remember being advised to 'rough-up' any contact surfaces during surface preparation.
    I do remember that within minutes of the two surfaces coming together, although I could slide the 130watt panel assembly side-ways it was virtually impossible to lift the panel vertically.
    That was three years ago.
    Good luck!

    On Line see :- (PDF) SIKAFLEX-512 Caravan-Sika UK. for instructions
     
    Last edited: Jan 11, 2014
  3. williamb

    williamb Read Only Funster

    Joined:
    Apr 28, 2008
    Messages:
    42
    Likes Received:
    14
    Location:
    Lancashire
    Panel

    Hello, if the mounts are solid bottoms roughing them with some course sand paper and doing the same to the points on the roof will hold the panel no problem. Having said that I think your motorhome has a aluminium roof which is only very thin and is only laid onto the roof if so that is where your week point will be.:Eeek:
     
  4. Wissel

    Wissel Read Only Funster

    Joined:
    Sep 16, 2013
    Messages:
    301
    Likes Received:
    323
    Location:
    Cornwall
    With regard to the satellite thread - does anyone know if it was Sikaflex that was used?

    I've never heard of Sika failing, my bet would be a cheap silicone was used instead.

    Everything on my roof is stuck down with Sika and is rock solid. I was really sceptical about using a glue instead of screws or bolts but was reassured unanimously on a self-build forum that it was the best way. I think every builder on that forum has just used Sika for solar panels or anything else stuck to their roofs. Never any problems. I know a lot of people also use it to fit bonded windows to the side of vans. Again, never heard of a failure.
     
    • Like Like x 2
  5. pappajohn

    pappajohn Funster Life Member

    Joined:
    Aug 26, 2007
    Messages:
    29,443
    Likes Received:
    16,873
    Location:
    YO11 2BD
    dont forget, once the panel is in place you need a couple of millimeter gap between mounting feet and roof.
    Dont push the feet right down to the roof.
    Easiest way is a small spacer, maybe washers or a small piece of plastic, set in the adhesive then push the feet down to that.
     
    • Like Like x 2
  6. SomeoneElse

    SomeoneElse Funster

    Joined:
    Apr 22, 2013
    Messages:
    571
    Likes Received:
    375
    Location:
    Cotswolds
    I'm about to do a similar thing, fitting two 130W panels.
    I contact Sika for advice and they suggested I use Sikaflex 252.
    Their product range is very confusing so I don't know the difference or the merits of the various products.

    I now class myself as an armchair Sika expert, but its very worrying and I wondering whether I should dare to attach them myself.

    Some tips I have acquired during my research are:
    1. Roughen the surfaces to be bonded with 100 grade wet and dry.
    2. Wipe the surfaces with the cleaner/activator is one direction only, using a cloth wetted with the cleaner. Wipe once only with any surface of the cloth, then use a clean new area of the cloth for the next wipe.
    3. Don't apply the Sikaflex in crosses or circles as air is then trapped when the joint is made and is compressed when the joint is push together the air can then push joint open again. Always apply it in straight lines so that air can escape from the ends.
    4. Sikaflex 252 should not be used below a temperature of 15C, so it looks like I'll have to wait a month or three before I get the benefit of my panels. You need to check the technical data sheet of the product you are using.

    BTW Like you I'm using ABS plastic mounts but my van has a painted GRP roof.

    I'm hoping some real experts will comment on this thread. Please report back on how you get on.

    Gordon
     
  7. hilldweller

    hilldweller Funster Life Member

    Joined:
    Dec 5, 2008
    Messages:
    26,418
    Likes Received:
    25,075
    Location:
    Macclesfield
    Hope is good.

    Holding your breath isn't.
     
    • Like Like x 1
  8. Moodybrook

    Moodybrook Funster

    Joined:
    Jul 7, 2013
    Messages:
    754
    Likes Received:
    628
    Location:
    Dumfries


    I looked up Sika 512 and quote - " To ensure satisfactory conditions for curing, do not apply at temperatures below 5°C or above 35°C. The optimum temperature for substrate and sealant is between 15°C and 25°C. " there is a graph which indicates that at lower temperatures the curing takes longer. I will leave it until I can get a 10C at least day or two. In Scotland that will be June or July ? :Laughing:

    Thank you everyone, for some good pointers. My panel arrives this next Thursday, just got a phone call from delivery contractor. I am busy routing the cables forward to the roof area, Trunking the cables inside some water piping, along the chassis member , allowing a bit of leeway to connect. :Smile:
     
  9. Techno

    Techno Funster Life Member

    Joined:
    Jul 28, 2010
    Messages:
    13,847
    Likes Received:
    14,496
    Location:
    Leeds the one up North
    • Like Like x 2
  10. SIFTA SAM

    SIFTA SAM Read Only Funster

    Joined:
    Jan 27, 2009
    Messages:
    454
    Likes Received:
    452
    Location:
    Leyland Lancs

    It turns out that it was indeed Sikaflex 525 that I used for my solar-panel fitting.

    Comparing Sikaflex 512 and Sikaflex 252 Product Data Sheets, 252 is the better for Shore A-hardness, Tensile Strength, Tear propagation resistance, and others.
    As yet have found nothing about any necessary surface pre-roughing with abrasives, and the minimum application temperature for the 252 is 10C as opposed to 5C for the 512.
    Some data for the 'experts' or even 'real experts' :thumb:
     
  11. SIFTA SAM

    SIFTA SAM Read Only Funster

    Joined:
    Jan 27, 2009
    Messages:
    454
    Likes Received:
    452
    Location:
    Leyland Lancs
    Sikaflex 252 is the way to go! More expensive but worth it (as I have found):thumb:
     
    • Like Like x 2
  12. Moodybrook

    Moodybrook Funster

    Joined:
    Jul 7, 2013
    Messages:
    754
    Likes Received:
    628
    Location:
    Dumfries
    My problem Is that I am (My van) likely to get evicted out of my shed, sometime in late February so the slightly more amenable temperature constraints of 512 would be an advantage. I want to get on with it !

    I hear what you are saying about 252, however quite a number on other threads advocate 512 so I would be reasonably happy with either, I have got 512. :Wink:
     
    • Like Like x 1
  13. Taran_Las

    Taran_Las Funster

    Joined:
    Mar 26, 2009
    Messages:
    6,476
    Likes Received:
    5,519
    Location:
    Near Mold North Wales
    Not an expert but I applied 512 on a dry day at 5°c and slightly below. I left it covered for a day to cure. No problems experienced. I did clean the surfaces using 205 cleaner/activator. Techno100 produced an excellent thread outlining a method to install panels. See here response no 7.
     
  14. SomeoneElse

    SomeoneElse Funster

    Joined:
    Apr 22, 2013
    Messages:
    571
    Likes Received:
    375
    Location:
    Cotswolds
    I am pleased to stand corrected on the temperatures, as its good news for me, there will be days of 10+ temperatures earlier than the 15 I had in my mind, thank you.

    As to the abrasive treatment recommendation it was originally given to me by a guy from the local car body repair shop. I apparently ensures that any remaining road grim or wax from washing is removed. He only suggested a light rub over to get back to the true substrate.

    In the Sika Marine application guide (page 6) The state for Glass fibre reinforced plastic decks they recommend the following:

    1: Heavily soiled surfaces should be cleaned off first with a pure solvent (Sika ® Remover-208) to remove the worst of the soiling
    2: [HI]Lightly abrade[/HI] the contact area with a sanding pad
    3: Remove the dust with a vacuum cleaner
    4: Treat the substrate with Sika ® Aktivator-205, using a clean, lint-free rag or a paper towel. Change the rag frequently!
    5: Apply a thin coat of Sika ® MultiPrimer Marine using a clean brush, a foam pad or a felt applicator

    Thanks for your help
    Gordon
     
    • Like Like x 2
  15. SomeoneElse

    SomeoneElse Funster

    Joined:
    Apr 22, 2013
    Messages:
    571
    Likes Received:
    375
    Location:
    Cotswolds
  16. Techno

    Techno Funster Life Member

    Joined:
    Jul 28, 2010
    Messages:
    13,847
    Likes Received:
    14,496
    Location:
    Leeds the one up North
    You will find that is plus £7.50 flat rate shipping and then plus VAT

    You can find it on ebay at £14.99 delivered
    I prefer to pay £10 more for 4 times as much :thumb:

    It will keep for years as long as you don't leave the cap off for longer than needed.
    As long as the liquid is clear it is still ok

    EDIT http://www.ebay.co.uk/itm/Sika-Akti...61064339949?pt=UK_Gadgets&hash=item25802ec9ed
     
    Last edited: Jan 12, 2014
    • Like Like x 2
  17. Peter_n_Margaret

    Peter_n_Margaret Read Only Funster

    Joined:
    Oct 27, 2013
    Messages:
    87
    Likes Received:
    62
    Location:
    Adelaide, Australia
    The way I achieve this is to place small patches of double sided adhesive foam tape of the required thickness to one article with Sikaflex in between.
    The tape maintains the correct Sikaflex thickness and holds the 2 parts together until the Sikaflex sets.
    Easy peasey...

    I built the motorhome in the avatar.
    Structurally it is totally held together with Sikaflex 252 (plus the appropriate cleaners and primers).
    For "lesser" jobs like solar panels I use Sikaflex 11FC because it is easier to use (no primers), sticks like the proverbial and is more flexible (so thinner beads are needed to allow for differential expansion between parts).

    Cheers,
    Peter
     
    Last edited: Jan 16, 2014
    • Like Like x 1
  18. pete4x4

    pete4x4 Read Only Funster

    Joined:
    Jan 17, 2010
    Messages:
    16
    Likes Received:
    5
    Location:
    Northants
    Agree with everything that has been said including needing to leave a gap. I used tile spacers, the recommended gap for 512 was 3mm and that happens to be the exact dimension of a tile spacer laid flat, because they are a cross you only need one either end of the mount to maintain a uniform thickness
     
    • Like Like x 1
  19. stevebill

    stevebill Read Only Funster

    Joined:
    Jun 23, 2010
    Messages:
    26
    Likes Received:
    95
    Location:
    UK sometimes
    adhesive sealants

    OK, Im a bit late with this, but Ive just read through the thread and heres my five penn'orth.
    Sealant is one thing, but adhesive sealant is quite another.
    I have used a product called Marine Flex. Get it from marinemastics.com
    It seals - after all its a marine product- and it is a tremendously good adhesive.
    I have used it in conjunction with fibreglass tape, and also with 2 pack epoxies. If the two happen to touch whilst wet, theMarineFlex doesn't curl up and "pickle" - Sikaflex does.
    Sikaflex doesnt hold a candle to it.
    Its white- so you can see exactly how much bead you are running.
    Its cheaper than Sikaflex.
    good luck with the project.
    Stevebill
     
  20. Moodybrook

    Moodybrook Funster

    Joined:
    Jul 7, 2013
    Messages:
    754
    Likes Received:
    628
    Location:
    Dumfries
    As a conclusion to all the help and tips that you have contributed, I thank you.

    My eagle has landed, definitely needed the extra tube of 512 and I did get a can of aktivator at the same time. I did rough up the mounts and the roof surface then cleaned carefully with the aktivator.

    However following on from WilliamB s' advice about the nature of my roof and another lead I found on the net, shock horror. I chickened out and have also bolted the beggar down just to be sure.

    I may end up with a coupe or a mobile shower but the panel will still be attached to the roof, wherever the roof may be ! Sikkaflexed up to the gunwhales, albeit with 3mm tile spacers (simple great tip) to give that crucial depth to allow for temperature movements and general flexing.

    I am still not fully connected up, this weekends job. Of course not road tested either but hopefully with all your help the job should be a goodun. I am more confident of what I have done than in the general construction of the rest of the van. Us Scots shipbuilders made them to last, you canna beat a guid bolt !
     

Share This Page