Cleaning GRP panels

paulkerryg
paulkerryg Forum Participant Posts: 10
edited June 2016 in Caravans #1

Hi, we are new to the concept of caravanning and currently looking around and building up a picture with a view to purchase a van after the 2017 models are launched. 

Having read through lots of threads about damp, warped windows, EHU issues, delamination, etc which has been enlightening, I thought I might be able to offer something back to the community.

I work with GRP daily and have seen references on here and other forums on the use of T-Cut to clean GRP.  

I would personally recommend you stay away from T-Cut unless you are sure of its providence due to past issues with Gel-coat discolouration. Older T-cut used amongst other things, ammonia in the lubricant so I wouldn't go and grab the pot you have had in
the garage for twenty years and start cleaning GRP, you may regret it!  

With the same token, I would stay away from using magic sponges on Gel-coat surfaces due to their abrasive nature unless you are prepared to polish out with a fine polishing liquid after.

 Personally I would use 3M Cleaner Wax to
remove marks; if it has scratched, then you need to use a compound or polish to refinish (polish out the marks) and then make sure you protect the new surface with a high quality wax.

Car waxes are not particularly good on GRP gel-coats as they tend to offer less UV protection than marine GRP waxes.  Car wax tends to work in combination with lacquer to protect paint; Gel-coat has no such protection and needs to rely on a good coat of
high quality wax.  

Wax protection is removed all the time by rain and washing, it needs replenishment on a regular basis; we maintain boats on the south coast and we look at the way the water is shedding from the surface as an indication of when the wax needs another coat.
 In the marine environment that can be up to four times a year.  On a caravan, I would guess about twice a year.

Finally, be careful and picky on your suppliers, there are stories of boot-leg products on the market causing ammonia like yellowing in the last couple of years.  A very well know online auction site isn't always your best friend.  If its cheap, there is
normally a reason.

Hope to see you out and about in 2017,

take care, Paul.

Comments

  • Dickdastardly1
    Dickdastardly1 Forum Participant Posts: 153
    100 Comments
    edited June 2016 #2

    What do you think of this product, I bought some and find it had good results?

    Crystal Glo Automotive Marine Surface Restorer 470ml Paint Gel Coat Metal Polish.

    I also use boiled linseed for the door trims and mirrors

     

     

  • paulkerryg
    paulkerryg Forum Participant Posts: 10
    edited June 2016 #3

    What do you think of this product, I bought some and find it had good results?

    Crystal Glo Automotive Marine Surface Restorer 470ml Paint Gel Coat Metal Polish.

    I also use boiled linseed for the door trims and mirrors

     

     

    I need to declare an interest as I supply GRP cleaning products to some of my customers, however, I will try and offer an impartial viewpoint.

    I guess the real yardstick will always be, has it delivered an acceptable output based on the input - by that I mean was the end result better in your eyes than the cost to buy and the effort taken to apply, remove and buff.  

    It is always hard to assess products that claim to be 'one pass', as the GRP panels on caravans tend to be vertical and therefore I doubt that your GRP was badly oxidised, likely more dirty, and you probably applied Crystal-Glo by hand and got a great shine.

    It is when the GRP is beyond just dirty that the debate starts getting interesting.  Add nano/poly coatings into the mix and we could be online talking for weeks!

    I recommended 3M Cleaner Wax because I recognise its limitations and happy to sell it to my customers.  It isn't magic in a bottle but a fix for a specific issue.  If the surface is scratched then a self-diminishing abrasive is required and these come in
    various forms, the best products in my opinion coming from 3M and Farecla.

    Crystal-Glo surface restorer is the same; it has a place for a specific issue.  My reservation is the claim that it is a "special one step polish/conditioner that effectively cleans and eliminates heavy oxidisation, minor scratches, surface rust, embedded
    dirt, corrosion, yellowing, chalking and fading. Works quickly to produce a high gloss shine while adding a weather-proof, UVA/UVB SPF 30 and scratch resistant coating", if only life was that simple...   Smile

    Cheers, Paul

     

  • Dickdastardly1
    Dickdastardly1 Forum Participant Posts: 153
    100 Comments
    edited June 2016 #4

    I have a motorhome which has gel coat skirt, grp roof which has lost its sheen although it is clean and metal sides, so as an amateur it is difficult to know what are the best products for different surfaces.... I will try the crystal glo on the grp and
    see it works. What wax would you recommend?

  • paulkerryg
    paulkerryg Forum Participant Posts: 10
    edited June 2016 #5

    I have a motorhome which has gel coat skirt, grp roof which has lost its sheen although it is clean and metal sides, so as an amateur it is difficult to know what are the best products for different surfaces.... I will try the crystal glo on the grp and see it works. What wax would you recommendIs I have a motorhome which has gel coat skirt, grp roof which has lost its sheen although it is clean and metal sides, so as an amateur it is difficult to know what are the best products for different surfaces.... I will try the crystal glo on the grp and see it works. What wax would you recommend?

    Is the GRP painted or is it a coloured gelcoat?  It makes a difference on the cleaning product and type of wax.

  • Dickdastardly1
    Dickdastardly1 Forum Participant Posts: 153
    100 Comments
    edited June 2016 #6

    the skirt is gel coated in a grey colour whilst the grp on the roof is white

  • paulkerryg
    paulkerryg Forum Participant Posts: 10
    edited June 2016 #7

    The white gelcoat on the roof will suffer oxidisation due to being horizontal.  It, like the top of my head, needs all the UV protetction it can get!  I would be looking at a heavy paste wax rather than a liquid.  Not what you want to hear as paste waxes
    are harder to apply and work with, but it is hard to find a good, long lasting, liquid wax with a high UV protection.

    As for the gray side skirts, if they are clean I would stay away from them with any one step product as they will introduce fine scratches.   Just give the skirts a good wash and dry and then use a good wax, personally I would stay with the same product
    as the roof but you could use a liquid wax if you wanted.

     

  • The Jolly Northerner
    The Jolly Northerner Forum Participant Posts: 2
    edited April 2019 #8

    Hi Paul

    The GRP on one side of my van is very dirty, I have tried numerous cleaners on it but to no avail.

    The opposite side is fine as this was reapplied about 5 years ago due to faulty GRP. 

    It looks like the dirt is under the gel coat.

    Can you suggest anything please.

    Moderator Edit:

    Please note that the OP is from 2016 so I doubt that you'll get a response after such a long time but maybe others can help.

  • Unknown
    Unknown Forum Participant
    edited April 2019 #9
    The user and all related content has been Deleted User