There are some very, very talented people out there. I’ve seen some DIY drawer systems that rival and sometimes easily exceed the professional gear you buy off the shelf. However, there are a lot of drawer systems that are not very well built too, and I’m always on the lookout for ways to do things better.
I’ve always enjoyed working with timber, and given the time I’ll happily give most timber things a crack. I extended the drawer system in our 80 series Land Cruiser, and built the new one in our Dmax (and have just re-done it to suit a different fridge), and have picked up quite a few things along the way.
I was always into building furniture, and nearly went down that pathway as a career, and know my way around anything that’s made of timber fairly well.
4WD Drawer material choices
In general, you have a couple of choices when it comes to building a drawer system for your 4WD.
Marine ply is the top of the range; its designed to get wet and not be destroyed, its got great strength and looks top quality. The big downer, is the cost; you’ll pay a fair bit for it
Construction ply is the next cheaper option, and you can see why as there are imperfections in the surface. If you can live with this, then by all means its a good option, and its actually pretty good for water spills too.
MDF and chipboard
I would not use MDF or chipboard for 4WD drawer systems. Its not very strong, and is terrible if you get any water onto it. The timber swells, and will be a bin job. MDF is also extremely heavy for what it is!
Ally drawer systems are fantastic. They are light weight, strong and they take up very little room. However, they cost by far and away the most, and are not as easy to DIY.
You can, however, buy some pretty neat aluminium extrusions and elbows and join it all together to make the frame which is strong, light weight and easy to work with.
Some of the professional drawer systems on the market use steel, at least for a portion of the drawer supports and systems. Steel is insanely strong, its pretty economical and easy to work with. However, its also very heavy, and for this reason alone I wouldn’t recommend it.
Why is ply thickness so important?
The thickness of your plywood directly correlates to strength and weight. The thicker the ply, the stronger its going to be, and the heavier it is too.
18mm plywood is very strong, but its also insanely heavy. However, you don’t need to build a drawer system out of thick (and heavy) timber to make it strong. A huge part of the strength comes from how you join it all together, and what bracing you put in place to keep it strong.
The thickness of the timber that you choose should also be directly related to your skills. If you struggle to mark things up well, cut it squarely and drill straight, you’ll have a hard time trying to get a series of 40 – 50mm screws to go through the ply properly, and can end up with them busting out the side. Not only does this look rubbish, but you’ve weakened the structure too.
How to screw it together
I mentioned above that my preference is to screw the bits of timber together, using 40 – 50mm timber screws. I pre drill the bit of timber that its going through, and countersunk it. Ideally you want to drill a hole through both pieces of timber that’s the same size as the screw section shank.
The timber on the outside should be drilled to the same size as the screw, so it slides in and out easily. In this way, the screw will cut a new path into the timber that you are pulling it together using the pilot hole, and both bits of timber will be screwed together well. Tighten the screw up until its flush, and you are good to go.
To re-iterate, I’ll drill a 2mm hole for the screw to screw into (if the screw thread is about 3.5mm), and a 3.5mm hole for the screw to slide through.
If its a short piece of timber, and I need it strong, I’ll put screws every 80mm. If its longer, or I don’t need it so strong, I’ll put them 100 – 120mm apart. If you get the hole sizes right, and put the screws in properly it will be rock solid and even the corrugations won’t make them come out.
Quality ply or aluminium
If I was building a nice drawer system, I’d pick one of the above. I prefer 12mm plywood. Its well and truly strong enough when glued and screwed properly (every 100 – 150mm with 40 – 50mm screws) and it wont weigh so much that your drawer system weighs more than what you want to carry.
Watch the weight
Drawer systems are amazing. They make accessing gear so simple and quick. The only downfall is their weight. Many drawer systems weigh around 70kg unloaded, and that’s a lot of weight to have attached to your 4WD. Guaranteed you are pushing the weight boundary already; how far can you afford to go?
If you are going for drawer systems, seriously consider using teflon, or polystone strips instead of heavy slides, as you can save a huge chunk of weight.