Paint finish

[Chippygeoff]

Hi Everyone. I am reliably informed that among you good people there are some real experts who could possibly solve my problem. I am cutting small quantities of of top grade birch plywood and MDF, both in 4mm thickness to a size of 10 x 8 inches and both will be used in more or less the same application. This is an ongoing thing with me so I will be making the boards for quite some time. I need to spray some black and some white but I am having problems getting a good finish. I am trying car spray paint and also acrylic paint. So far I have given both materials five light coats of spray paint but they are still patchy. I realise now with the ply I will have to apply some form of sealer but I am not to sure about the MDF. I thought this would have readily taken two coats and look nice but this is not the case. Any advice would be greatly appreciated. many thanks.

Geoff.

 

[Chrispy]

Hi Geoff
I think what you need is MDF primer sealer, you can also use it on the plywood. it over comes the wax / glues in the mdf that makes finnishing patchy also it has a good filling effect after one coat de nib and give a second you should have a surface like glass. I would recomend pigmented A/C lacquer over the top super finish I use 20% sheen for furniture and kitchens slightly easier than full gloss to get that near perfect finish.

 

[Chippygeoff]

Many thanks Chris. You have put me on the road to success. You will have to forgive my ignorance of this as I am in unknown territory here and out of my depth. Is the MDF sealer/primer brush on or spray on and what does the A/C stand for with regard to the lacquer. I apologise for being so dumb on this.

 

[Chrispy]

Sorry, primer sealer spray on, you could just about brush it but you will get so much better finish with a spray gun. A/C stands for acid catalized it a 2 pack lacquer

I now thinking that you may have been useing spray cans for the car paint, if so and you don't have a spraying set up you could give the car type primer filler a go as the base coat under the car paint you are using as an option.

 

[mailee]

Chrispey is correct. You need a primer sealer for both the MDF and ply. If you are spraying it with a gun then I would recommend Morrells AC laquer and primer. I will warn you though that it should be sprayed with an air fed mask or a compliant mask for AC finishes. Morrells also make a water based system which is more user friendly. I use the solvent based AC laquer on Mositure resistant MDF and it takes two coats of primer sanding lightly in between coats and then two top coats for a high gloss finish. It is also available in variable sheens. HTH.

 

[Chippygeoff]

Thanks Crispy and Mailee. I do not have a spray gun so have to rely on cans. I am not that good with a brush and think I will get a better finish from the can. I have taken what you said on board and scanning the spray paint section on e-bay have bought some cans of black paint and some cans of grey primer, it stated that it was suitable for wood and I had a mail from the guy selling it and he said several of his customers bought the same stuff for wood so i could be on a winner here.

When I have painted the boards I fix another piece that is cut to a shape on the top made from hardwood and glued and clamped with titebond. when it has all gone off nicely I spray the whole thing with Chestnut acrylic satin lacquer but at nearly £8 a can it is expensive. I looked on e-bay thinking I would find something else quite cheap but found stuff there much more expensive. I don't know if any of you guys use this sort of stuff but if so do you know if i can get this finish cheaper somewhere.

 

[Chrispy]

If your using this much why not get a small spray gun then you can put anything in it? 5L of pre cat lac or primer filler each about £40 > £50, no idea how much you get in spray can? but a proper gun is so much easer to use and shouldn't make much more of a "cloud" than the cans your using. or use acrylic thats water based more expensive but goes further.

 

[mailee]

Depending on the sort of finish you want you may be better off using a foam roller to apply the paint. As Chrispy has stated it would make more sense to buy a cheap spray setup and use the AC laquer. Using spray cans will cost you a fortune trying to get a good finish. HTH. :wink:

 

[Chippygeoff]

Thanks again guys. I work in a spare room inside my bungalow and don't have any room left. I have an outside shed but i could not use that except in the summer because it is so cold out there at present and heating is not an option as some of it is open to the elements. I am quite happy to use the cans as it only adds roughly 50p per item so it is well within budget. Incidentally. The paint and primer/sealer i have ordered will be here tomorrow but in the mean time I am getting good results using a cellulose sanding sealer, two coats and then two coats of spray paint. I am well happy with the results.

 

[woodaxed]

Hi
I make a lot of painted mirrors using mdf and have found the easiest way is to give the mdf a coat of pvp glue diluted 50/50
with water just brush it on and leave to dry