Skip to content

Double stacking my Mac Allister storage drawers together

As part of my home electronics workbench, I purchased some storage drawers, so that I had a plentiful selection of storage for my small parts and components, and they’re then individually organised so that I can quickly find them

After buying a couple of these. I noticed that they had holes at the top of each one, which in theory means they could be stacked. When I first looked at this, I couldn’t find any obvious connection point, but figured it was possible. There’s holes there right?


Disclaimer: This page contains affiliate links. If you choose to make a purchase after clicking a link, I may receive a commission at no additional cost to you. Thank you for your support!


Why the need to join the bins?

This wasn’t really needed, I just wanted to do it. So that I could have a small set of parts drawers, and a large set stacked on top of them. I then get a few large components drawers as needed for my electronics workbench.

In order to stack the Mac Allister storage bins on top of each other, I used a few tools, and had to do a quick small modification to the one that was stacking on top.

I’ll document it here, because I noticed in the FAQ for the B&Q website that some other people have thought of the same thing, and found it to be a problem. As they can’t be stacked either, so this is how I did it. So if people find this article, and want to do it themselves. Feel free to use this as a starting point if it helps you.

I’ve been revising this procedure each time I do it, so that I can figure out what works best and is the fastest. The first time I went to join them together took about 30 mins+ because it was so fiddly. Using the technique I use here, I can join two sets of bins together in about 5 mins. They’re nice and stable.

What you need to join the bins together?

You don’t need many tools or components, but these are the items I used to join the bins together. In terms of the consumables. I normally buy pan head screws as they’re what I had on hand. The nuts and washers I already had as I purchased these from screwfix before in a yellowbox. The items I note below are close enough to what should work. The nuts and washers are small that I have, maybe 6 or 7 mm in size for nuts and 9mm for washers max (can get away with not using washers).

  • M4 nuts, bolts and washers (the nuts / washers aren’t exact I used but should work)
  • Philips and Flathead Screwdrivers (assorted sizes) MAGNETIC IDEALLY!
  • Longnose Pliers (or scissors work)

What do the bins look like?

These are the two Mac Allister parts bins from B&Q that I purchased for use in my electronics workbench storage (I now have 6 of each in total). For the price they’re “OK”, the metal isn’t exactly thick, it’s like 1mm, but the benefit is they’re made of metal. The drawers are a hard plastic. The only downside is the spot welds can break easy. Other than that for the price you can’t really complain, when you compare it against other storage bins for the same price.

Initially I was using B&Q, but the problem is that each storage regionally only has 1 or 2 of each. You can buy them from B&Q sister site (Screwfix), at a more expensive option, but they’re ordered in (my local stores didn’t do click and collect). I had to hunt around because people were damaging and stealing the drawers which was irritating, as it cost me an extra £30 overall, but I plan on making that back by manufacturing parts for sale anyway

These are the products that I purchased and their links if needed. The larger smaller drawers are the 24 compartment ones.

Two Mac Allister storage bins from B&Q and Screwfix to double stack together
Parts bins I’ll be stacking together

Just another picture of the Mac Allister parts bins. I have to give credit to the person from Screwfix in the stores who looked after them. He actually inspected them all as he purchased some himself for his own project. Called to advise one was damaged, and offered a refund, or could order more from the warehouse. I chose the latter. Got the final four of them today (£111.96 lighter).

Four MacAllister 24 drawer parts bins side by side
Parts bins purchased from Screwfix

A pic of the larger unit. The good thing about these two designs is that other that the height, and number of bins. The external dimensions are the same. So they’re basically designed for stacking

50 drawer Mac Allister parts bin from B&Q
50 drawer parts bin to double stack

Stacking the Mac Allister drawers together

In order to minimise any damage to the metal, using a small pair of needle nose pliers, then using a piece of tissue, rag, sock, whatever. Cover the edges of the needle nose pliers, then stabilise against the outside of the metal, and squeeze inwards (using the tips of the pliers). You don’t need to squeeze much as it’s only thin metal anyway so bends easy. It’s just enough to get room to put the nut on the bolt and inserting it.

Using tools to fold back the metal
Minimise the damage done to metal with pliers

After using the pliers, you can see how the metal has been folded inward into the housing to get access to the holes for inserting the bolts from underneath.

Screw fixing holes visible on MacAllister storage bins from B&Q
Where the metal is bent inwards to access

As you can see, it does leave minimal damage. If you’re really funny about any kind of damage marks, either this isn’t the mod for you. Or just press in the metal with your thumb on the inside. Just be careful not to injure yourself. The metal is thin enough so it should bend easy

The small indents of damage left against the metal
Damage left by pliers when protected

I’ve found the best way is to remove the top set of drawers from the Mac Allister storage bins that you will be inserting the bolts into for stacking. This helps give room to work with

Removing the top storage drawers from the MacAllister storage bins in B&Q for accessibility to double stack together
Removal of top storage drawers for accessibility

Needle nose pliers (or a pair of scissors) are a handy tool to have for this. I find myself using them to put the washers on top of the bolts once the bins are joined together

A pair of minotaur long nose pliers
Long nose pliers tool

Another useful thing is if you have fingers like oak trees (like me), you aren’t quite dextrous, so nimble tasks need a bit more perfection. Here I’m inserting the bolt with the pliers for fitting. The procedure is actually a bit different now, but picture just for clarity.

Using needle nose pliers to hold M4 Bolts
Using the pliers to insert screws

After the bolts have been inserted, attach a nut

Upper bolt to fix two drawers together
Easier method of joining drawers together

After inserting the bolt, add a nut on the top, this makes it easier to assemble it. Don’t tighten the nut all the way up, this is just enough so it holds the bolts on for easier fitting when stacking together. Eventually it will all tighten up once fitted

A simple method of joining MacAllister parts bins together from B&Q
Joining the drawers together with M4 nuts and bolts

For the Mac Allister storage drawers where you will be stacking them on top. Removing the bottom drawers should be all you need to do for access.

Removal of drawers to double stack units together
Removing the bottom drawers to gain access

After the top storage has been mounted over the bolts, there will be limited accessibility. I normally hold the washer with a pair of pliers or scissors, then use the magnetic side of a flat blade screwdriver to slowly turn the nut onto the bolt. It only needs to get on a couple of threads, then you can turn the rest by finger

Using a screwdriver to hold a nut inaccessible by fingers
Using a magnetic screwdriver to add a nut to thread

A magnetic screwdriver for all its usefulness

Using the tools to fix parts together
Benefit of magnetic tools

Once the bolts have been inserted between the stacking units. It’s quite hard to get access to tighten the nuts, or even put them on. The best way I find is by using the magnetic screwdriver tip to slowly turn it onto the bolt. Normally you can draw a circle using the nut once it’s on the bolt and it will self tighten. After this you can use your fingers

Holding a nut with a magnetic screwdriver
Making use of a magnetic screwdriver for nuts

Holding the rear nut in place with the flat blade

Securing rear screws with long blade screwdriver
Holding the rear nuts in place

Position of the Pozi screwdriver through the rear access mount

Position of screwdrivers for accessibility
Where to position screwdrivers for fixing parts drawers together

This is the position of the screwdrivers I use to tighten up the rear. A Pozidrive through the rear screw mounts, and holding the nut from moving with the flat blade

Using tools to fix together the MacAllister parts drawers from B&Q using the mounting holes
Parts drawers secured together

After the drawers have been mounted, I simply bend the metal back into place

Fixing metal that was bent
Using a screwdriver to straighten up metal corner

After the unit has been fully assembled. Just use a small screwdriver to bend the metal back if it bothers you, or thumbs to bend the metal as its thin enough. Just be careful as it can be sharp.

Straightening up metal with smaller screwdriver
Using a small screwdriver to straighten up the metal

Straight up the metal in place

Fixing the damage done to the metal
Tidying up the metal again

The drawers are then fully secured at each end after tightening them up. I recommend leaving the washers off from the front to save room

Drawers secured with M4 nuts and bolts
Securing the Mac Allister parts drawers with nuts and bolts

The drawers are then fully assembled and you can reinsert all the trays as it’s secured together

Fully assembled Mac Allister drawers, double stacked together
Two Mac Allister storage drawers from B&Q stacked together


Like the article? Consider browsing more of my site, and read other articles.

I recently signed up with Virgin Media broadband, as they offer “high speed” internet when I had limited suppliers in my area for the same price as my existing ISP

If you’re considering changing ISP, you can use this link to sign up to Virgin Media (affiliated) and we both pocket £50. They offer up to 1000Mbps internet speed (with 100Mbps uplink) on residential packages. My article above gives an unbiased review with honest feedback on using the service so far.

Or, if you’re more of a nerd. Here’s a QR code you can scan which does the same thing

Sign up to Virgin Broadband with my QR code and earn £50 towards your account
Virgin Media affiliate code