help please!!

[burgo]

whilst flatting back the primer on my roof i noticed lots of this shizzle

http://i12.photobucket.com/albums/a226/sclurgess/S7303073.jpg

http://i12.photobucket.com/albums/a226/sclurgess/S7303072.jpg

if i had to guess i would say it was to high pressure causing it. problem with that is when i turned the pressure down it came out sorta spittly.

if my diagnosis isnt correct then what is it and if it is what can i do to stop it.

thank please muchly

[bmw156]

is it filler or fibre glass

looks liek some air has got trapped and now your sanding the top of the bubbles off lol

other then that i have no idea lol

[saloonwoody]

flat it back wet :)

[burgo]

the primer is over filler but the filler was proper flat so its not from pin holes. i am woody

[bmw156]

hmmm, maybe when you sanded befor you were like fractions of mm over the bubbles and now you have takens the tops off

[burgo]

if you mean bubbles in the filler then im not down to that yet. this is bubbles in the primer im guessing

[Plug]

dont worry your cars just gettin chicken pocks wont last longer than a week or so

[saloonwoody]

could be air that was trapped in the filler which has bled thru ?

[burgo]

could be air that was trapped in the filler which has bled thru ?not sure. there was very few pin holes in the filler tho and this holes are over the hole roof.

they do flat out but i keep braking through the primer to flat them out

[Jack]

Looks like the surface or the paint has been contaminated.

I've got a similar thing in the paint work I'm doing at the moment, and its a PITA to stop it happening :(

[burgo]

i prepped the quarters and tailgate the same and they dont have the pitting lol. pain in the **** thing

[Nobby]

got to be some grease under there mate, flat it back basically all the way then use a decent preclean then very slowly build up the paint like spit it on 1st couple of times then flat it back again with some very fine sandpaper so just the top top layer comes off then pre clean again then paint slowly and build it up. My cesaros were the same but came up ok after i was told to do that :D

[Nick J]

Its hard to say without seeing it properly but it looks like lots of dirt within the primer? Could have splattered out of the gun in the first coat and then you've recoated over the top? especially if you've been priming before hand and you've not cleaned the gun out properly. Or the primers started to go off in the gun and caused it..... Possibly this if the roof was the last panel you've got to??

If its either of the above a flat and reprime will cure it fella.

Nick.

[Paul]

Panel Wiped the surfaces down prior to paint?

Could be a reaction?

It looks like beneath the primer you have used to coarse paper as you can see surface scratches. may just be the photos?

[~~joycey~~]

Seems like a reaction to me?

[CoolTiger]

as above looks like its silocone'd (sp)

[dougie_boi]

what size of cap are you using on the gun? what ratio did you mix the primer at?

[ade]

its pin holing. a classic paint fault wehen spraying on fibreglass or filler.
No matter how smooth you get filer you always get microporous holes - when spray paint the paint sinks into them causing a pin cushion effect.

Simploe remedy - flat back and skim using fine surface filler or cellulose putty - you can get it from halfords etc.

Should always apply this as a skim whenever you use filler. Allow to cure (usually 24 hrs) then flat back but dont take all off - best to leave filler covered.

Ade

[burgo]

if thats the case tho why is it only the roof that has gone like this? the rest of the car which is covered in filler is fine.

i think i have worked out what it is anyway.

as im spraying it the overspray is settling on the roof as dust and then when i try to go over the dust i get those air pockets