These aluminium cases have been made in my garage at home
using normal tools most households have. I wanted something strong, cheap and
of the size that suits me the best, right from the start it was clear that waterproofing was paramount.
I will try to explain step by step how I made them with pics
and some brief descriptions (for those who understand the language there will be the Italian version
on the web soon). Please feel free to ask any question.
Note that I haven’t been working on a proper workshop and
the tools used were far from be professional, I have used a normal old wooden
table and some tools I always had in the garage so tool-wise it is a cheap job.
Please consider that this is my first attempt to make waterproof alu cases for motorbike purposes and if I'll ever need to make them again I will probably do it in a slightly different way as at the end I realised that either something wasn’t necessary or it would have been easier doing it differently. Time to time I will give some tips learned the hard way.
The only part of the case I had made outside were the lids.
The lids are simply two alu sheets (3mm thick) folded and welded at the four
corners. For this I went to a place where they make commercial signs for shops
and restaurants, they did it for me the same day, easy job for them.
Another option, but I thought of this later and it would
have been actually the best option if you have time to look around, is to find
the two lids first, they can be the cut-out bottom of a box, of a jerry can or
any other container with the right dimensions and then build the cases around
these. Sometimes we came across, have at home or simply throw away perfectly functional lids for our alu boxes, the other day I was looking at my neighbur's canary cage: the tray at the bottom was aluminium and quite appealing...
Another example: a couple of metal jerry cans with a cast handle at the top would made perfect lids.
Anyway, this is how:
Alu sheets 2mm thick (plain alu sheets with no pre-coating I think will give the max of adherence between the materials)
Alu L profiles, 3x3cm, 2mm thick (brown ones in my case as they were the only ones in stock at the shop when I went)
To cut alu sheets this way: a ruler (a steel one is better or simply use another allu sheet as a ruler) and a paper cutter, once marked bend the sheet on the edge of the table. The cut will be perfectly straight.
To cut the alu Ls this way: it doesn’t need to be a precise cut as it will all be covered up by the steel Stackable Ball Corners at the end.
roughly like this:
Drilling the holes:
I suggest to drill the holes on the alu Ls first then use the L as a guide to drill on the sheet, clamps prevent them to slide while drilling
Drill bit: depends on the rivets you use, for 4mm rivets use a 3.8mm bit ( I didn't...) if available as the rivets will fit tighter in the holes, this is because with a hand drill you always have to take into account the "human" tolerance: with a 3.8 bit you will always make a 4.0mm hole at least. I used a 4mm bit anyway and the rivets were 4x7mm (7mm is the length)
Once the holes are done use a 8mm or thicker drill bit and manually take off the excess of aluminium from the hole's edge on the inside (in this way the Ls and the sheets will adhere neatly) If the surfaces where the sealant will go are dirty clean them with some diluent or some non-oily detergent, important is that this doesn’t leave any film or else behind, diluent is optimal (petrol is not good)
Once done this apply the sealant on the L (not too much), three thin lines: two near the edges and one right across the holes.
(Tip: before you start with the sealant make sure you have PLENTY of paper and within reach...!)
Join the materials and move the L back & forward a little so to make sure the sealant reaches all the surface in between (see arrows), don’t be afraid to make a mess.
now the rivets: put some sealant on the rivet as pictured
stick it in the hole, make sure the sealant comes out a bit, if not take it out and add more sealant
In the same way put the rest of the rivets in place. This
way we are sure all holes are aligned. Start pulling the rivets from one end to the other: the sealant will spreads more even and air bubbles, if any, will escape.
Once u have pulled all the rivets make sure the sealant overflows from around the rivet's head and from edge of the L, this guarantees the joint will be waterproof. Leave the excess of sealant as it is: once hard you will cut it neatly with the paper cutter.
Proceed with the other aluminium sheets and Ls, make sure you have all the holes done before you start with the sealant.
Tips: first do the 4 sides of the boxes, then the bottom. It is easier to do the sides two by two then put them together.
Once the 4 sides are together (the box is finally having a
shape) fit two Ls (one long and one short one) to the alu sheet that will be
the bottom then fix it permanently to the box. Once this is done fix the other
two Ls to complete the case, this way we will have enough room to spread the
By now you will be probably swimming in sticky black sealant...