I'm a finishing idiot...

[Redback]

I'm frequently lost when reading this forum. I admit I know almost nothing about finishing, I've read most of Neils book, but still theres so much to understand!...

I'm currently finishing a low cabinet / Entertainment unit which will be holding the DVD, Receiver, Set top box etc for my projector home theatre room.

To fit in with the speakers and other units, I wanted it black so it would fit in with the look of the room. Therefore I decided MDF was the best material.

I am currently sealing and undercoating with dulux primer/sealer. My next stage is to paint the whole thing in a Dulux low gloss enamel.

On my test piece, I got lots of little bits of dust and airborne particles. Given that I don't really have the ability to make a dust proof room, how can I get rid of this? On the test piece I experimented with some 0000 steel wool, then rubbed back with EE ultra shine. In a low light room, it looks and feels great, but with a direct light it looks crap and you can see scratches everywhere.

Can anyone advise on a procedure to finish this unit?.

I am currently intending to sand my back my sealer tonight, with 120 grit, then do the first coat of enamel (note I am roling this on with foam rollers, I dont have a spray gun). Tomorrow night cut that back with a 240 grit then apply a second coat.

I was then thinking of cuttin this back with EE ultra shine to see what happens.

Any advice. I think ive read every MDF related thread in this forum and still not sure...

note to Soundman : In my original question some months ago (I got sidetracked), you mentioed using Jet Dry paving paint. I have been unable to find a black Satin paving paint. Mitre 10 tell me they don't make it....

Probably the wrong thing to do, but I ended up going with enamel paint over buying GMH black too....

cheers

Redback

[ubeaut]

Personally I reckin cutting back with 120 grit is way too harsh 240 or better still 320 would be much better even try 400 or higher. The finer the base the better the top coats will be. Why don't you buy some satin black spray cans they are everywhers and a dime a dozen and they have to do a way better job than what you are planning on doing.

Cheers - Neil

[JackG]

Hi Redback,

I would address the problem another way, if your problem is dust particles and other on a flat gloss shiny surface perhaps you should question if a flat gloss shiny surface is what you really want ? You will see every mark scratch dent not to mention the additional dust not imbeded in the coating..

For large areas I prefer to use some texture that not only absorbs buiding "features" but also operational "mistakes". Try a fairly thick paint and use a foam roller or a texture roller, there are other techniques but this is the easiest and most consistent finish. Some paints are also designed to give a texture.

If you persist on a non textured finish you can dry your pieces vertically to minimise deposits..

Hope that helps

[Redback]

well Ive already undercoated it with this oil based primer.

I just tried to sand it and its still a bit gluggy after 30 hours or so. must have been a tad too cold last night and today!.
It also didnt fill up some of the surface imperfections very good either, which is what I was expecting it too do.

This has got disaster written all over it

Give me Jarrah, that was much more fun to work with!.

What is a good type of thick paint to apply now.

(I'd do Neils suggestion if the undercoat had worked, I now need something to cover some holes....(ie I had edged it in pine, but hadnt worried too much if there was a slight gap, cos I thought it would fill, but it hasnt).

Gah, I think Ive just wasted quite a bit of time and money

[Gumby]

well Ive already undercoated it with this oil based primer.

I just tried to sand it and its still a bit gluggy after 30 hours or so. must have been a tad too cold last night and today!.
It also didnt fill up some of the surface imperfections very good either, which is what I was expecting it too do.

This has got disaster written all over it

Give me Jarrah, that was much more fun to work with!.

What is a good type of thick paint to apply now.

(I'd do Neils suggestion if the undercoat had worked, I now need something to cover some holes....(ie I had edged it in pine, but hadnt worried too much if there was a slight gap, cos I thought it would fill, but it hasnt).

Gah, I think Ive just wasted quite a bit of time and money

There are undercoat/fillers which are very thick and are made for filling imperfections. They are also very chalky so easy to sand. Your local paint store would be the go.

[Redback]

but would it go over the oil based crap Ive already got on ok?, or do i need to sand it back to wood/mdf again?

Roll on Summer..!

Then if I do use that filler stuff, would I be better off using a Satin Black spray can that Neil says?. or some kind of thick paint as also mentioned...

Basically what I would like is a Satin look, but something reasonably hard wearing that isnt going to peel or scratch or chip at the drop of a hat...

And as I said, Im a finishing idiot...

All I know how to do at the moment is apply shellac and polish with wax (and that is at least rewarding on a nice bit of wood)

[Gumby]

but would it go over the oil based crap Ive already got on ok?, or do i need to sand it back to wood/mdf again?

Roll on Summer..!

Then if I do use that filler stuff, would I be better off using a Satin Black spray can that Neil says?. or some kind of thick paint as also mentioned...

Basically what I would like is a Satin look, but something reasonably hard wearing that isnt going to peel or scratch or chip at the drop of a hat...

And as I said, Im a finishing idiot...

All I know how to do at the moment is apply shellac and polish with wax (and that is at least rewarding on a nice bit of wood)

I think I'd get it off and start again .

[Shaty40]

If you go into a decent paint shop, (not your lacal hardware) I am sure they will show some products that will go over what you have already, and allow you to start again from there.

I know taubmans make sealer that will stick to anything but can't remember waht it is called.

Tim

[Trav]

You can get this stuff called 3in1 or something that covers oil based undercoats and lets you paint over it with anything you like.

If I was in your position, I would:

1. let the undercoat dry out as much as possible. You might bring it into the house to speed things up as it will be warmer.

2. sand this back a little to give you a reasonably smooth base. Use 120-180 grit. Don't worry about sanding it all off, but get rid of any lumps.

3. Fill any gaps with a suitable filler/putty. Sand back again with 180 and then 240. Paint never fills holes and bumps, it just makes them look worse. The trick to using MDF seems to be to make the box cleanly, and minimise any sanding and filling.

4. Paint it using an enamel satin black paint - any paint shop should be able to supply this. Use a little roller or one of those paint pads.

5. cut back with 400 grit wet and dry (just a light rub to get rid of any painting marks or bits of dust.

6. see 4

7. see 5

8. behold your creation in all its satinny glory!

You might like to do the last coat in a spare room or something rather than the shop. Paint it and then close the door softly and don't open it again for 48 hours. If your shed is anything like mine, it is covered in sawdust. Sawdusty shed = bad paint jobs.

My 11c worth

good luck

Trav

[NewLou]

Gidday Redback,

If it were me I'd cut it back first then sand as per Neils suggestions.............Finishing is all about patience and just taking things 1 step at a time...............as soon as we rush things we all become finishing idiots!

TIP: Do not coat M.D.F. first up in oil undercoat or oil primer. It may activate waxes within the board. Always use a water-based product first to prime MDF.

If you decide to cut back the Oil based stuff & prep the MDF as per suggeested I'd get a few Cheap plastic drop sheets from Bunnings or where ever and set up a finishing area (This will dramatically reduce dust contamination) particularly if your careful to keep clean. Bear in mind you might have to wear some kind of appropriate respirator.

By Finishing area what I mean is to literally hang the Drop sheets from the cieling so in effect your creating a clean space in the workshop to do your finishing work.

I tend to agree with some earlier suggestions to perhaps get some advise from local paint suppliers heres a few weblinks that might help:

http://www.focusdiy.co.uk/stry/diy04...ry,diycategory
http://www.focusdiy.co.uk/invt/44960
http://www.woodweb.com/knowledge_bas...shing_MDF.html
http://www.infolink.com.au/articles/a8/0c02d9a8.asp
http://audiokarma.org/forums/archive...hp/t-1094.html

This will kick you off Redback ....................Do a few Google searches and trall your way through the info..........No matter what hang in there ......be patient & don't get the Fk'Its!!!

..........Good luck with it m8 n keep us posted

REgards Lou

[Redback]

ack, decisions decisions. Some good sounding advice there guys, thanks.

This is what I have used for the undercoat...

http://www.dulux.com.au/html/plannin...rep_coats.aspx

Dulux 1 Step™Oil Based Primer Sealer Undercoat

Dulux 1 Step™Oil Based Primer Sealer Undercoat is suitable for interior and exterior surfaces, especially timber. It has excellent hiding power and good sanding properties. It is recommended for use over weathered timber. Ideal for priming all timber when the topcoat is to be an oil based finish.

Which sounds good, but didnt do a very good job of filling in my opinion!!.

This is what I have already bought (and sampled) for the top coat

http://www.dulux.com.au/html/plannin...e_enamels.aspx

Dulux Super Enamel Semi Gloss

Used on interior trim areas such as architraves, skirting, doors or wall areas which are subject to excessive wear. Super Enamel Semi Gloss provides a smooth even finish where water based products are not appropriate. Note: Enamels will yellow in the dark, hence discolouration of WHITE will occur and is a natural product characteristic.

Im not wanting to have to sand all that undercoat off (a: because I have glued some parts together already and getting in to sand this out would be nigh on impossible). Secondly, I spent quite a bit buying this stuff, so I want to make it work if possible. On my sample piece it came up pretty good, as long as I can keep the dust off.

So anyways, Trav's ideas seems the way to atm. One thing I now need to know is what is a good filler to put on top of the dulux 3 in one. Soundman mentioned on a thread somewhere automative filler. Would that be the way to go here? What other type of filler would be appropriate? name? where to get?

thanks for all the help everyone.

cheers

RB

[Trav]

Hi Redback - I can't really recommend a filler for you sorry. I have heard good things about auto fillers.

Trav