MDF preparation

[CMac]

Hi all,

Finally decided to build a (hopefully) decent looking stand. Picking up the 18mm boards tonight so just need to gather the rest of the gubbins.

My main question is about the preparation of the sheets and stand. But I'm sure I will be back once it is underway!

Do I need to do anything to the inside edges before construction? Sanding or sealing?

It will be glued and screwed for construction.

Thanks in advance,

CMac

 

[Tim Harrison]

Have you seen this thread? https://www.ukaps.org/forum/threads/diy-ada-style-aquarium-stand.31348/

 

[ian_m]

Having built MDF furniture before (kiddies nappy changing unit), I just sand the edges and don't seal otherwise glue will not stick.

I used waterproof wood glue and screwed the joints together.

Mine was sealed with MDF sealer, having used diluted emulsion before and not happy with the results. Apply using a small roller.

Then couple of coats of emulsion paint, as that is available in 100's of mixes and colours, followed by multiple coats of solvent based varnish. Also used gloss paint as well in making book shelves.

Just need to be careful in the design that you are not putting shear or pulling forces on the joints if screwing, or else the MDF will split into layers. You can of course use the clever joining connectors Ikea use like these
http://www.screwfix.com/p/cross-dowel-m6-x-14mm-50-pack/77320

Oh and extra protect any areas that might accidentally come into contact with water, so any MDF at floor level, shelves etc.

 

[CMac]

Have you seen this thread? https://www.ukaps.org/forum/threads/diy-ada-style-aquarium-stand.31348/

I have been using that as my guide so far but if I missed where it mentioned about the inside of the joints then I am sorry for clogging up the board!

Having built MDF furniture before (kiddies nappy changing unit), I just sand the edges and don't seal otherwise glue will not stick.

I used waterproof wood glue and screwed the joints together.

Mine was sealed with MDF sealer, having used diluted emulsion before and not happy with the results. Apply using a small roller.

Then couple of coats of emulsion paint, as that is available in 100's of mixes and colours, followed by multiple coats of solvent based varnish. Also used gloss paint as well in making book shelves.

Just need to be careful in the design that you are not putting shear or pulling forces on the joints if screwing, or else the MDF will split into layers. You can of course use the clever joining connectors Ikea use like these
http://www.screwfix.com/p/cross-dowel-m6-x-14mm-50-pack/77320

Oh and extra protect any areas that might accidentally come into contact with water, so any MDF at floor level, shelves etc.

That's just what I was looking for thanks, I am a complete beginner so I am grateful for it spelt out!

Light Sand
Glue and clamp
Screws
MDF sealer
Paint
Varnish

Did you sand between coats of sealer/paint/varnish?

Cheers,
CMac

 

[Tim Harrison]

I have been using that as my guide so far but if I missed where it mentioned about the inside of the joints then I am sorry for clogging up the board!

No worries, thought it was at least worth pointing out just in case, if in doubt always ask that's what the forum is for

 

[ian_m]

That's just what I was looking for thanks, I am a complete beginner so I am grateful for it spelt out!

Light Sand
Glue and clamp
Screws
MDF sealer
Paint
Varnish

Did you sand between coats of sealer/paint/varnish?

You first screw together all the MDF bits, to test that it all fits "perfectly", possibly making some "squared edged templates" of surplus MDF to hold things at right angles whilst the glue sets.

The then glue and screw all together, wiping off any surplus squeezed out glue.

Leave for a while for glue to set.

Yes you use fine sand paper to sand between coats. Sand by hand as power sanders will tend to cut into

Use a small roller, possibly diluting the paint (I have used slightly diluted Hamerite on MDF before) as it doesn't leave any brush strokes.

Or even better, but extremely messy (in terms of dust) is to spray on Plasti-kote. I built a "spray booth" by hanging dust sheets on the garage & hanging the MDF from the ceiling by length of wire (you will also need a light as the sheets make it all dark !!). You will need a breathing mask and possibly eye protection and a suitably sized wallet to purchase the not so cheap paint from B&Q. Spray lots of thin coats allowing to dry between coats. Plastikote with a layer of clear protective coating is the doggie danglers of finishing work. Finished surface is mirror flat and virtually indestructible. I built a book & toy shelf this using method is blue Plasti-kote, absolutely no chips, surface blemishes despite abuse by my kids.
http://plasti-kote.co.uk/