Blooming Paint!

[Mark Wilson]

I've previously sought and received advice on painting in cold weather. I decided to leave it till Spring, which is now on us. The temp in my garage tonight is 5C and I'm committed to spraying celly the week after next. I'll warm the garage as advised, but there would seem to be some risk of blooming. How serious is this? If I'm flatting and compounding in any case will this remove the bloom?

Mark

[trabant]

HI I'd warm the metal to be painted slightly as well and keep it that way the garage would be best warmed for a couple of days beforehand too. Primer is hydroscopic meaning in damp conditions it soaks up water that's why panels.left in primer get brown staining ( rust ) coming through therefore if you just warm the garage before painting you risk mixture being trapped under your nice shiny new paint. This will lead once its out in the blazing summer sun to the moisture trying to escape and your lovely new paintwork being ruined by micro blisters the same goes for polyester body filler as well by the way. To stop blooming you'll want considerably more than five degrees and absolutely the best quality paint thinners you can find DO NOT use standard cellulose thinner use an anti bloom thinner.

[graham1957]

i have not used celly for about ten years but as above use the recommended thinners or good quality thinners, dont use the 7 quid a gallon stuff because the paint will dry dull, no shine and no amount of polishing will help! i know ive do it, i cant advise on blooming as ive not experienced it.good luck with it and let us know how you get on with it.

[graham1957]

be careful heating garage as celly thinners very flamable when sprayed so no naked lights and compressor in a different room, the cut out pressure switch can spark!!

[bmcecosse]

Indeed! I know some lads many years ago now who had a big wood burning stove roaring away while they sprayed a car - and there were shelves of paint stacked along the wall near the stove. They escaped with their lives - the car and the garage were destroyed.......

[PaulTubby]

Yes a warm enviroment is very important.. my tip is to fill a bucket of warm not boiling water half full and place the tin of paint in the bucket for a few minutes.. this will warm the paint before you use it.. also id use the best quality thinners you can.. ici is best other then that get the garage warm but dont forget to damped the floor with a watering can to keep the dust down before spraying as the spray gun can blow dust and dirt all over your work as you get to the bottom of the panels

[amgrave]

When I sprayed celly in the 70s we had the choice of slow, medium or fast thinners to use dependant on the temperature we sprayed in. I don't suppose the options are available now though. We never suffered from a bloom finish.

[trabant]

personally I'd wait till much warmer weather as you're going to have to keep it warm while keeping it incredibly well ventilated. I've not used celly in years the modern stuff isn't a patch on what it was and its five times the work of 2k if your going to use cellulose Lechler is exceptionally good cellulose paint and considerably less pricey than ICI. I have just had 5 litres of Nexa 2k clarendon grey mixed for slightly over £100 as I do all my own resprays that's a nice cheap job.

[kennatt]

unless you have a good heating system,I would forget about it until the weather warms ,you will have all sorts of problems,sags,runs and blooming',and inside a small garage you have the risk of inhalation of fumes,even with a good mask,better outside unless you have an extraction system.. but there are some ways of countering it' Buy an infrared heater so you can direct it at one panel at a time(No flame so no ignition),you can still buy slow thinner(Anti bloom),do one panel at a time(a slow laborious job needing repeated masking off etc),put several thin coats on to prevent sags/runs.Keep the door shut until the paint flashes off,blooming is caused by a drop in the temp on the panel caused by the thinners evaporating helped by a sudden cold draft. If you do get blooming ignore it,it can be polished out (usually).If you are using celly you will need to cut the paint back anyway because its pretty cra.......p these days looks nice and shiny and as soon as it hardens off it goes dull(That's why most pros now use 2k) Which ,if used outside as a one off, is not as deadly as some people think its prolonged use where the risk of asthma comes into play. good luck

[Mark Wilson]

Thanks all. It's a Traveller shell which I want to get to rolling chassis stage. If the temperature doesn't rise much I'll either abandon the deadline (yet again) or stop before the cab roof and B pillars, which will be the main visible panels. The outer panels can wait a couple of months.

My compressor is in an adjacent store, so should be OK. I need to remember to turn off the power to the boiler, which is in the garage. Fortunately it isn't the old pilot light type!

I'll look out for Lechler paint - I was going to use Jawel which has been well spoken of on here.

I wasn't sure about wetting the floor as I didn't want to introduce any more moisture than necessary, but on reflection it sounds like good advice.

Mark

[bmcecosse]

I found 'blooming' was more down to moisture content in the air - so never on a wet day! Try to pick a sunny/low humidity day. And yes - after poisoning myself with celly thinners one time (dizzy and unwell for several days ) - after that I have only ever sprayed outdoors in still/warm weather. But avoid direct sun - I have seen the paint turn to dust before it hits the panel!

[kennatt]

yes partly bm,the thinners evaporates dropping,the temp on the panel below the dew point then moisture get onto the panel usually happens below 10 deg.

[rcharman]

.....(That's why most pros now use 2k) Which ,if used outside as a one off, is not as deadly as some people think its prolonged use where the risk of asthma comes into play. good luck

So wrong to quote this, professional vehicle refinishers use a fully enclosed suit with fresh air supplied to a hood in a spray booth to apply 2K paints. It is a temperature controlled environment for spraying, and all of the volatile organic compounds are filtered thoroughly before entering the outside environment. The hardener for all 2K contains isocyanate (google it and find out how dangerous this chemical is) so stating a "one off" use is irresponsible. Imagine if all club members and amateur vehicle restorers had this attitude worldwide, asthma would be the least of their worries. I have taught Vehicle Refinishing for 30 years and have never allowed any student to spray or mix 2K unless they wear in a sealed paint mixing room, wore the correct safety clothing and breathing apparatus.

If I saw a person spraying this dangerous material around, I would be notifying the EPA (Environmental Protection Authority) and let them impose a heavy fine for their "one off" use.

Rod

[MrIan]

So as this 2K paint is so flippin lethal (been reading HSE notes on it) ie air fed mask and full suit / extraction filtered spray booth and no one allowed in till cleared after application .
WHY IN GODS NAME DO WE STILL USE THIS STUFF ?
What is the benefit of it over celly taking into account the environment also.

[amgrave]

Celly is carcinogenic too, just not so much. Minimum requirements of protection would be cover all if not most of bare skin and a good dust mask. This is talking as a home sprayer and not a professional.

[bmcecosse]

Most professionals use water based paints now. And you are correct about the 2k paint when sprayed , I've been trying to spread this message for ages - but there are always some who ignore it, or 'know better' - even one dose could prove lethal (especially if deeply inhaled - and then it 'sets hard' on the lungs!) - perhaps not immediately - perhaps in years to come when the isocyanates get to work. Don't do it!

[MrIan]

Well I still can't see how on earth the paint spraying world advanced by going to 2K paints, don't tell me some pen pushers with power decided celly was too harmful for the environment and decided on 2K paints as the way forward ?
What paints are recomended / available for the DIY car restorer at home for 1 off resprays ?

[Dean]

Well I still can't see how on earth the paint spraying world advanced by going to 2K paints, don't tell me some pen pushers with power decided celly was too harmful for the environment and decided on 2K paints as the way forward ?
What paints are recomended / available for the DIY car restorer at home for 1 off resprays ?

The only "advance" I believe is that 2k is very hard, produces a better finish with less paint and the car doesn't suffer those rusty stone chips like they used too.

Other than that it can kill you eventually.

Unless you really know what you are doing use Celulose for DIY. Oddly enough one of my neighbours commented on the nice smell coming from the back of my garden when my dad was spraying my mog with celulose.

[bmcecosse]

The 2K gives a 'false sheen' to my mind -can spot a car so sprayed easily. And try patching up a dent or rust spot Fortunately 'Classic' cars are still allowed to use cellulose paint. Just be sensible with it.

[trabant]

BMC clearly hasn't realised 2k had moved on since 1980 modern 2k good quality stuff when cut and polished in fact our local funeral cars are done it.I agree cheap 2k ( binder system ) paint looks plastic a high solid 2k doesn't and is perfectly easy to do blend in repairs with. Celly is just as toxic as 2k I wouldn't spray either without suitable protection.
Most professionals now use water based base coat which is a complete load of twaddle as it still has to be lacquered with a 2k lacquer. Water based was bought in to satisfy EU VOC levels the basecoat does the rest doesn't so totally and utterly pointless legslation .