Dulux Eggshell problem (now solved) then MDF painting tips

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With the garden hose fitted I am finally producing a spray finish I am happy with :)

Thanks for the suggestions and sympathy. You may have helped keep me sane though all this :lol:

All seems so easy now.
 
Hi there,new to this forum but find it very interesting always good to hear other opinions.
Robert sorry to hear about your problems with your Fuji.
I have just finished a refit of my stepsons bedroom with built in units etc all made out of MDF. In the past I have made units etc out of MDF and hand painted them which is where I felt let down as to the finish.
I tried everything to try and achieve a professional finish but never got there!!!
So this time I decided to invest in a Fuji Pro4 system,at the moment it still sits in the box unused,after reading the problems that you have had I am wondering whether I should return it while I can get a full refund ! Would be interested to know if you solve your problem,and if anyone else out there has sprayed MDF with a HVLP system succesfully?
 
Welcome to the forum.

I'm spraying it pretty good now :)

If I do sell the Q3 on ebay when I'm finished I will buy another (new this time) next time I need to spray. Think I'd go for the Q4 too as a little more pressure would be nice.

I think something has happened to sponge intake air filter and it has contaminated the whole air path through the unit including the hose with minute specks that repel paint when they find their way into the applied film. There seems to something about eggshell paint that causes the reaction as the primer and most of the undercoat went on fine.

Now that I have shaken any loose debris from the turbine and changed the hose it is performing beautifully and has restored my faith in HVLP.

I still don't like the fan control on the fuji gun and am using it with no fan but apart from that it is a good system now.

I have bought some aquarium air line valves and tubing to replace the fuji pot pressurising pipes and they work well and cost only 35p each (the valves are easy to accidentally ruin with paint getting into the pipe)
 
Robert,

Did you buy the Fuji from new or is it second hand ?

Spraying eggshell is extremely messy, why not try some pre-cat lacquer 10% sheen which is pretty near eggshell, plus it dries so much quicker.

Paul
 
2nd hand.

Think I'll persevere with the eggshell. Now I have the baffling problems solved it actually does not take that long to get a decent finish.

Also not sure where I'd buy something like that. Can't see my local trade decorators centre having it on the shelf.
 
Robert, glad you got your paint problems sorted. I was wondering if you could give me any tips on spraying with the Fuji?
I am going to use a HVLP for the first time,having never sprayed before.
I am going to spray eggshell (um!) onto mdf,I realise that I will have to seal the mdf first with a proper sealer and pay attention to the raw edges which I read somewhere you can do with drywall filler.
The bit I need help with is,what kind of primer to use and how much do you have to thin the paint?
Any help and any further tips from anyone, would be most welcome.
Regards, Mark.

_________________
My partner doesnt understand my power tool fetish!!!
 
RobertMP":3b4tnylp said:
2nd hand.

Think I'll persevere with the eggshell. Now I have the baffling problems solved it actually does not take that long to get a decent finish.

Also not sure where I'd buy something like that. Can't see my local trade decorators centre having it on the shelf.

Morrells supply all wood finishes ( Welyn Garden City and North London)


Chippyjoe":3b4tnylp said:
Robert, glad you got your paint problems sorted. I was wondering if you could give me any tips on spraying with the Fuji?
I am going to use a HVLP for the first time,having never sprayed before.
I am going to spray eggshell (um!) onto mdf,I realise that I will have to seal the mdf first with a proper sealer and pay attention to the raw edges which I read somewhere you can do with drywall filler.
The bit I need help with is,what kind of primer to use and how much do you have to thin the paint?
Any help and any further tips from anyone, would be most welcome.
Regards, Mark.!!!


I get excellent results using Dulux oil based primer mixed with Dulux eggshell 2 parts primer 2 parts eggshell 1 part white spirit as a primer and then 2 coats of eggshell. I know it sound a strange combination but I have used it for years on kitchens etc without any problems. It works even better if you are using dark colours.



Paul
 
I'll give you a run down on what I did a bit later.

I will say though that if I do this again I will use an oil based primer as the water based mdf primer seems to stay too porous.
 
Tips based on my experience so far (which is this one job and a test piece I did before the project)....

Use the green moisture resistant MDF not ordinary. MR because the edges cut cleaner and sand up much easier not because of moisture resistance. I don't know what drywall filler is - I just sprayed it with primer.

You need a primer to penetrate the fibres and seal the surface and enough thickness so that when you rub it down you still have sealed surface left. I used Leyland MDF primer because it worked well on the sample I made and painted. When it came to recoat it I found it to be a bit too absorbent and caused little mounds of paint solid that looked a bit like dust spots. These spots mostly levelled out on drying. As said above next time I'd try an oil based primer. To get over the absorbant primer I am giving my doors 1 coat of Dulux trade undercoat before the eggshell.

The fuji can spray paint that is fairly thick and like brushed paint the texture from spraying thick does flow out level. Thick paint does not want to spray so it does need some thinning. I use the seconds cup to measure the viscosity. The primer was thinned with water to about 35 seconds and the top coat thinned with white spirit to slightly less - about 33. It is easier to get a good finish when the paint is thinned correctly. The right amount of thinning is when it sprays well but still has enough body to cover. Don't take my numbers as being right for you. You need a lot less thinner to go from 40 seconds to 35 than you do when the paint is thicker so be careful when the mixture is near to how you want it.

Thinned paint or primer does not seem to stay well mixed when left unused. I have a lidded plastic 5l container that I mix in and return any unused paint to it from the gun and give the pot another mix with a paint stirrer on a battery drill before starting work. i don't clean the gun - just refill it with freshly stirred paint.

Get some fine disposable paint filters and whenever you fill the gun strain the paint into the cup. I got 50 from ebay seller 'hugspaints' and they seem fine.

If you have never sprayed before spend a few days practising first. I have sprayed before but not HVLP so I painted all the cupboard doors in my workshop as a learning job. Getting an evenly applied WET film without sags or runs (from putting too much on) is what you are aiming for.

Make some jigs to make life easier with handling and access. I made a turntable and some stands and they have been great.

Spraying Oil based you need a good mask. I use a half mask respirator with a carbon filled 'organics' cartridge filter and can't even smell the paint. Pinch your nose after spraying oil based - any stickyness and your mask isn't working right.

Technique is down to practice and being methodical. Getting into a routine means you always end up with 4 edges painted and not 3.

Have plenty of old T shirt type rag handy and thinner for cleaning.

If you do completely screw up a panel you can always put some solvent on a rag and wipe all the wet paint off.

Dried paint around the gun nozzle comes off easy with cellulose thinners as used with car paints but don't let it near anything else :)

The gun has a top suspension point so have something with a hook sticking out handy so you can put it down without danger of it falling over.

Tack cloths are good but not essential. Having a dust free surface is essential. I have some cloths so I use them but a dry hand and air blown from the gun is pretty efficient at shifting dust plus you get to feel any imperfections.

Don't use any hand creams or barrier creams as your fingerprints may cause problems then.

Edited after thought tips..

Start spraying with the paint flow knob screwed in so there is next to no paint coming out. then unscrew until you get a flow you can cope with. If it is still difficult to control try reducing the air flow slightly with a tap in the air line.

Light - you need to be able to see what you are doing. Spraying say white onto white is hard to see. Wet paint reflects so if you have light arranged to reflect off the work piece at you, you can see what is painted and what isn't.

I'm off for another days paint spraying. If i think of anything else I'll add it :)
 
Just read through that. I knew most of it aready. It didn't mention crumbling intake air filter sponge on a HVLP turbine :)

I can laugh about it now :)
 
Robert, thankyou for your advice and tips they make good reading.
There has been some times when I wished that I hadn't purchased the Fuji(and its not got out of the box yet!)and just painted the units with a hand brush but I guess it will be worth it in the end.
So I guess it will soon be time to grab the bull by the horns and go for it,thanks again.

Paul,thanks for your input as well.Being totally ignorant on paint as I am,would I be correct in saying that you do not mix an oil based primer with a water based eggshell? I realise that in the real world the two do not mix but is this the same with paint? please excuse my ignorance.

Richard,thanks for the information on the Morrells website will give it a look.

Thanks again guys,
Regards, Mark.
 
Oil and water generally don't mix :)

Spraying can be quite straightforward. I've just put the final coat on the first 3rd of the parts for my kitchen refit. took about 2 hours.

My recoat routine is to lightly rub the face with 600 wet and dry (used dry) to knock off any nibs but be careful not to break through on edges and corners - takes 30 seconds or so. If I've handled the panel a lot then a quick wipe with white spirit on a cloth. On to my stand for spraying. blow with compressed air. Quick light wipe with tack cloth. Turn it over and spray the back. Turn it over holding it by the edges. Spray the edges. Spray the face. move stand with panel somewhere to dry.
 
RobertMP In the past i have found the art of spraying and the gathering of information about it very difficult to come by. I have asked here for info and got only general stuff, this thread has been very helpful and you have been very open and i thank you very much, I think if i had your problems it would have really got to me but you have solved them and we benefit thanks again.
 
You are welcome. Just explaining my problem helped me find a way to the answer.

Being a bit impatient I just fitted a 300 wall unit door panel to a wall cupboard end (as a trim panel) even though the paint is not fully cured. I chose the door with the most evidence of past troubles still showing in critical light - and it looks perfect in situ! So I'm well pleased at how this is going to turn out. I'll add to my WIP thread with pictures once the rest is installed tomorrow.
 
In this thread there was a question about cleaning up time after spraying.

As I had to clean my gun today I thought I would take some pictures as I did it. taking the pictures took longer than the actual cleaning so overall it was a little over 20 minutes so 10 or less without the camera :)

Before I start there was a question about overspray. The carpet scrap I stand on has been there all the time whist applying 4 coats to a complete kitchen worth of MDF and is pretty clean considering.
P1010050.jpg


The gun isn't that bad really as I cleaned it thoroughly before changing to black.
P1010051.jpg


Pull the trigger (no air connected) and let the paint in the tube etc drain out
P1010053.jpg


Empty the pot
P1010054.jpg


Splash of white spirit in the pot, fit to the gun and shake for a while.
P1010055.jpg


Spray paint and thinner mix into a rag. max flow and no fan. Repeat with more thinner. I'm using a eggcup full as a rough amount.
P1010056.jpg


The gun and cup afterwards.
P1010057.jpg


Little bit of white spirit in a bottle bottom taken from the recycling box.
P1010058.jpg


old toothbrush and a small bottle brush to clean the cap unit and the cup rim.
P1010059.jpg


I stuff clean rag into the cup and twist to clean the inside
P1010060.jpg


Dry paint on the outside I'll get off later
P1010061.jpg


Air cap off. It has dry paint on it.
P1010062.jpg


needle out
P1010063.jpg


Dipped the brush in the white spirit and cleaned the gun insides. Either blast it through with compressed air or stuff some t shirt rag in to clean it after this.
P1010065.jpg


Now the answer to the dried paint - cellulose thinners.
P1010066.jpg


Very small amount in another bottle bottom and put the air cap in to soak.
P1010067.jpg


While the dry paint softens I put a bit of cellulose thinners on a rag and clean the outside of the cup.
P1010068.jpg


So there it is all clean and not much waste thinners. I pour them onto the rag I used to catch the spray and put it in the bin.
P1010069.jpg


One other thing. The main cup was what I used for the bulk of the spraying. By the time I had finished there was a lot of dried paint on the outside. i put about an eggcup full of cellulose thinners into a plastic bag then put the cup in.
P1010070.jpg


Closed the bag round it and left it for 30 minutes. When I came back the paint just wiped off.
P1010071.jpg
 
Robert,that was very informative and helpful. So after all your problems ,was the end result as good as you hoped for? And are we going to see any pictures of the finished job?
I have yet to get my Fuji out of the box,still trying to locate an extractor fan at a reasonable cost!
Thanks again for all your help and tips.

Mark.
 
Hi all

Just a couple of points re spraying with eggshell.

1. As you are aware the air coming out of the gun gets quite hot- to reduce this problem you can buy another hose and effectively double the length. The other advantage of this is that you can now put the turbine in another room. My Fuji is one of the older noisier units so this is a boon- it also reduces the stress on the filter.

2. Do use white spirit but reduce the amount and supplement with Owatrol oil (an expensive mix of turps and linseed oil). Owatrol is pretty much the same oil you find on the top of the paint when it have been left standing for a long time. Owatrol reduces the drying time slightly, allowing a longer working window. It also "lubricates" the paint without thinning it.

3. Clean the gun by spraying white spirit, then empty and pour in Dulux Trade brush cleaner and renovator (I have only ever seen this is 2.5l cans in Dulux Decorator Centres- previously known as MacDougal Rose). Then flush the gun by spraying with clean water. If necessary you can leave the parts sitting in the cleaner for a week or too.

4.ALWAYS strain your paint, even if a brand new tin. You can also use small filters that sit in the gun's cup on the feed pipe.

Water based primers and oil based top coats are fine together. I have only experienced fish eyes when having used shellac as the base and not ensured that the surface was dust free.

I tend to spray with two pack acid cat (from morrell http://www.morrells.co.uk/products/wood/4 ).

No grain swell with the primer- gorgeous to sand back and you can dictate the level of sheen on the finish coat. The biggest plus is the drying time (minutes before you can handle). Down side- very toxic- smelly- risk of combustion and cost- offset by convenience though.

Overall it is much easier to get a pro finish with the acid cat and your hvlp will find it much easier to atomise it. If you do have areas of dry spray you can polish them out.

DO NOT SPRAY WITH OIL BASED PRIMERS!!! - I once made the mistake of spraying a walk-in wardrobe with oil based primer and ended up in a cloud of sticky mist. The paint took ages to dry sufficiently to sand.
 
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