I could not work on anything else much today. Outside it is still very windy and the workshop concrete floor was freezing cold even with the fire roaring in the stove. So I could not be there for more than two hours at a time and then I had to go inside to warm my feet for about the same. But I have managed to do something useful – three sets of jaws for my bench vice.
On the left aluminium, then beech wood and then spruce wood covered with an old carpet. I needed these for a long time and I had to do with impromptu padding the jaws of the vice with slabs of these three materials several times on each project. And impromptu padding leads to time loss each time you use it, not to mention the cussing. For a hobbyist making one – two knives per year it is not a big problem, but now…
The dark spots on the backside covered with masking tape are where a strong 6×3 mm neodymium magnets are hidden – they collect the magnetic dust in the shop very quickly. Thus the masking tape. I had eight these magnets for a long time and I had no use for them, so I have used them for this.
And the jaws work very well. The grooves on the alluminium ones might be a bit too shallow for stock thicker than 10 mm, but I am not going to do anything about them just yet, they do seem to work just fine as they are and I will probably need to hold even 3-4 mm stock in them more often than something bigger, so they cannot be too much deeper than they are.
Working with aluminium is a bugger. Whenever I have an urge to file, cut or drill aluminium, I usually sit down quietly in the corner and wait until it passes. But sometimes there is no way around it.
Did I already mention that working aluminium is a bugger? It is worth repeating. It is soft but relatively strong in tension. It is an extremely good heat conductor. And it is also extremely prone to galling and cold-welding. The end result is that it blunts and overheats saws and drillbits and clogs-up files and abrasives.
A few years ago I got a useful tip from a machinist at my former workplace. I complained about how filing and cutting aluminium by hand is more difficult than steel because of the clogging of the tool teeth. I told him that I tried using powdered chalk to coat the file and clean it with a brass brush – a tip from another machinist – to prevent this, but it did not seem to work very well. And this machinist told me “wet your file with alcohol to keep it cool”. And it does indeed help a lot. I still need to keep a brass brush at hand to clean the file from time to time, but the alcohol does prevent the shavings from sticking to it very strongly. And unlike oil, it dries off and does not make a mess, so I use it for drilling aluminium too.
Even so, it is worth repeating. Working aluminium is a bugger.