simple question by a beginner

**andrew29** · 14th June 2004, 01:22 PM

Hi,

I'm a beginner on a mission. I'm about to start making a modular storage unit out of MDF. It will be made up of cubes 450*450*400 so the total size will be 1800 high 400 deep and 900 wide. (2 cubes wide *4 high).

The question I have is:

At the intersection of the bits of MDF (especially in the middle) if I rebate both sides of a piece I imagine it'll become pretty fragile. The other option I'm considering is cutting halfway into the 2 pieces and fitting them together at right angles to form a right angle. I'm sure there isa name for this.

Any ideas/suggestion/plans?

Its a bit hard to explain, is there anyway of posting a diagram?

thanks muchly

**ozwinner** · 14th June 2004, 01:59 PM

Hi and welcome

I take it you want to put a shelf in each cube?
If so, and for joining the cubes together, I would just glue and screw.
If you cut a dado into the mdf to take the shelf it will weaken it, unless you intend useing 18mm mdf.
Also, if you are going to use 12mm mdf as the self, it will sag over time.
So I wouldnt bother with the dado unless you use 18mm stuff.

Cheers, Al

**derekcohen** · 14th June 2004, 03:52 PM

The other option I'm considering is cutting halfway into the 2 pieces and fitting them together at right angles to form a right angle.

Hi Andrew, welcome to the BB.

The term you are looking for is mitre. And, yes, a mitre join at the corners is the ideal join with MDF. The basic aim here is to increase the area for glue. MDF machines very easily so, if you have a table saw, this would be a straight forward task. You could get away with glue alone, but a biscuit or two would aid it alligning it all and strengthening it to boot.

Regards from Perth

Derek

**mikmaz1** · 15th June 2004, 01:17 AM

hi andrew,
i think the joint that you are refering to is a cross-halving joint. thius is where you take out equal amounts of wood from aposing members to form a 90* cross, hope ive described this right.
depending on what you are going to use the shelves for or what you are going to put on them 12 mm mdf should be strong enough , if in doubt use 18mm.
seeyasoon mik.

**Wood Borer** · 15th June 2004, 09:27 AM

Welcome,

You could use cleats under the shelves and screw & glue the shelves to the cleats. This will support the the shelves without losing strength in the carcass.

- Wood Borer

**Red neck** · 15th June 2004, 07:53 PM

Andrew,

Cutting a dado in the side to fit a shelf would only weaken the member until you install the shelf. By installing the shelf with suitable glue you are restoring the strength provided the joints are a good fit.

I would go with ozwinner and scrap the dado and just butt join with suitable screws from the outside.

As for joining the corners, a mitre as suggested by Derek will work well. When you have cut your mitres lay the cabinet out with the outside up and the mitres butted together. Apply tape to the outside joins and flip the whole thing over. Place glue into the 'Vees' and fold into a cube and clamp.

**bsrlee** · 15th June 2004, 11:58 PM

andrew29:

Get thee to a library! Really. There should be a heap of books there on carpentry & they will give you the 'correct' names for what you want to do, as well as showing you how to do it. And its FREE!

The "Woodworking Techniques' volume in Taunton's (publisher/editors) 'Essentials of Woodworking' series has a discussion & photo essay on making MDF boxes with mitres, tape & PVA glue (aka Aquadhere).

And don't give up if the first one (or more) don't quite work.

Thread: simple question by a beginner

Thread Tools

Search Thread

simple question by a beginner

Tags for this Thread

Posting Permissions