Spray finishing MDF edges - How I do it

[Richard Findley]

Hi all,

Let me start by explaining that I am relatively new to spraying and have learned through a combination of trial and error and hints and tips picked up from people in the know and of course the forum!!!

Here's what I do (and the products I use)

Cut MDF to size and run a hand plane over to remove machine marks. Rout mould (or in this case chamfer):

Hand sand with 240grit - Carefully!!

A coat of Morrells White Primer 8005/641 (Waterbourne)

This appears quite rough still but a light hand sand with 400grit removes all fluffy bits and leaves a smooth finish:

2 coats of Morrells 362 "Severe Use" Waterbourne Lacquer gloss white. I've found that there is no need to rub down in-between coats. In this case I also finished with a coat of clear 90% gloss as there was another detail on the surface that needed a coat to even the gloss all over:

I hope you have enjoyed reading this and that it is of some help to someone out there.

Cheers,

Richard

 

[JonnyD]

Hi Richard looks like you have got a good finish there pretty much how i do it.

I was just wondering how you got on with the morrells waterbased top coat. I usually use morrells Acid Cat lacquers but have been meaning to give the waterbased stuff a go and do my bit for the environment. I have tried the waterbased primer and was impressed by that.

Jon

 

[Richard Findley]

Hi Jon,

I've been very impressed by the waterbourne finishes. I don't have a spray booth so fumes are a bit of an issue for me. These finishes are touch dry in 1 hour and recoatable after 2 which is really the only down side compared to chemical finishes. They reckon that these waterbourne lacquers are pretty much as hard wearing as the chemical ones. The clean up is a lot easier with waterbourne. Just run under the tap and spray water through!! I love 'em!!

Cheers,

Richard

 

[Paul Chapman]

Looks good, Richard. What sort of MDF was that - ordinary or MR?

Cheers :wink:

Paul

 

[JonnyD]

Cheers Richard

I will give the waterbased a try. I am making myself some wardrobe doors so I will try it out on these before using it on any paid work.

Jon

 

[cornucopia]

looks like you have achieved an excellent finish richard-well done

 

[BradNaylor]

That looks like bog standard fluffy MDF, Richard.

You will find that the edges of MR MDF finish a lot more easily. Well worth the small extra cost.

I too use Morrells AC finishes. I might give the waterbourne ones another try.

Cheers
Dan

 

[Richard Findley]

Hi guys,

Thanks for your comments. Yes, this is bog standard MDF. I've heard a number of times on here that MR MDF is far better so I may well try it next time.

Cheers,

Richard

 

[imaginarynumber]

Hi Richard-

Re the waterbourne- are you using a compressor or turbine??? Do you get grain swell with the water based primers?

I too have only ever used the acid cat

Cheers

 

[Richard Findley]

Hi imaginarynumber,

I used to use a little Apollo "Spray master" HVLP system which was ok but when I started having troubles with the gun I bit the bullet and bought a compressor and proper spray gun.

I now wonder how I ever managed without my compressor and the finish with this gun is much improvroved as the gun is so adjustable you can tweek it to suit your needs.

The waterbourn is a great finish and it doesn't seem to raise the grain significantly. I had some slatwal panels made for me a while ago and they used some cheapo rubbish MDF which I have struggled to get the sort of finish I would like on but as you can see from the pictures adove, normal (good quality) MDF finishes well, as does timber.

HTH

Richard

 

[imaginarynumber]

Thanks Richard

Not sure that I have enough space for a decent compressor so i guess that I will have to stick with my Fuji HVLP.

I generally stick with acid cat as the gun is happy with it.

Although you say that the grain raising isn't too bad should I take that too mean that it is noticably more than acid cat primer???

When hand painting with acrylic primer I expect to spend as long sanding as I did applying the paint; generally back to the point where you see the parallel machining lines.

In your case are you sanding to denib or to flatten raise bits of grain.

Cheers

 

[yo_chuci]

what type of spray gun did you buy and from where...

is it hvlp?

 

[Richard Findley]

Although you say that the grain raising isn't too bad should I take that too mean that it is noticably more than acid cat primer???

Hi imaginarynumber,

What I said was: "The waterbourn is a great finish and it doesn't seem to raise the grain significantly"

I've not had any grain raising problems with it (appart from this crappy slatwall MDF) but I must admit to not having that much experience with Acid Cat finishes.

Hi yo_chuci,

My gun is a De-Vilbiss Signature gravity fed HVLP gun from Morrells. It cost me about £275, so not cheap but it's a fantastic bit of kit!! There are MUCH cheaper guns out there for the occaisional user. I've seen them from about £35 from places like Axminster.

As far as I understand it, there's nothing really wrong with the cheaper guns but they are pretty much "disposable" so you bin them if you have any trouble with them/if parts start to wear etc and buy a new one. With the dearer guns like mine, all of the parts are replaceable and servicable so (hopefully) will have a longer life span!!

Richard

 

[white_sw]

From you pictures, it looks like to have a fantactic finish there. I've heard lot's of good stuff about these Morrells finishing products.
Does anyone know where I can buy some in Bristol ? I wouldn't be using large amounts as it just for hobby use. I have my own
spray setup, however, have only sprayed cellulose paints on car's before.

Cheers,
Sam

 

[dellpitch]

Hi
Morrells have a Bristol depot, it is at Avonmouth, on the road to
Severn Beach, Tel 0845 4509070.

hope this helps

 

[lemonjeff]

Richard,
I resurrected your thread to find out how are you getting on with the morrells waterbourne paints one year on?
Is the 362 lacquer durable and as hard wearing as they claim?

Cheers,

Jeff

 

[Richard Findley]

Hi Jeff,

Thanks for your interest.

I am still using the 362 lacquer now so that probably answers your question!!

The claim is that it is as hardwearing as an AC lacquer and I certainly haven't had any problems with it. I use the black gloss more than anything else as one of my biggest customers speciallises in Gothic stuff and I make a range of Walking Canes and display boards among other things for them.

The Walking Canes are turned from Steamed Beech and I find that I simply use 3 coats, no rubbing down in between, and the finish is excellent. Further coats will increase the gloss. As you can imagine, the canes get well handled and I have not yet (touch wood!!) had a complaint about the quality of the finish.

The display boards are onto MDF so they get sanded with 240g and primed with the White primer. This is then sanded with 400g and 2 coats of the 362 applied. Again, an excellent finish which I have had no complints about it.

I hope this answers your question.

Cheers

Richard

 

[lemonjeff]

Richard,
Thanks for the update and info

coats of Morrells 362 "Severe Use" Waterbourne Lacquer gloss white

You also mention gloss black, I can't find any pigmented lacquers in their 362 range? Or are you using their 9 series Waterbased lacquers?

Cheers,

Jeff.

 

[Richard Findley]

Hi Jeff,

The 362 is available as clear, black or white (although I looked at their website and you are right, they don't show it!!) but they deffinately do cos I've got all 3!!! The Black and white only go upto 70% gloss though.

The 9 series are good for colourmatching and it goes on lovely but it is a bit easy to scratch so probably best to go over it with a coat of the 362 to add a bit of protection. I guess it depends on what you're using it for.

HTH

Richard

 

[lemonjeff]

Hi Richard,
I got in touch with Morells and your right they do the 362 pigmented, they will also colour match it as well.
I've just finished building a spray booth, I'll let you know how I get on with their paint.

Thanks for all your help

Jeff.