Aluminum sword build tips? -- myArmoury.com

T. Diamante · Posted: Tue 09 Aug, 2016 8:02 pm Post subject: Aluminum sword build tips?

I was helping my parents clean out their garage about two weeks ago, and came across some supplies my dad had stored. Most of it was scrap metal, but he did have a sizable piece of 7075 aluminum. He's a locksmith but I don't really know what he was doing with it. Anyway, I ended up taking it and I decided to turn it into a sword! Although I am fully aware that this will be a primarily decorative piece. I'm aiming for something like an Oakeshott type Xa. I have the rough shape and some beveling done, but the blade has a long way to go. Has anyone else here done something like this? And what was your experience working with aluminum?

Jesse Belsky · Industry Professional

Hello T., that's a great looking blade you've got going. I happen to make a lot of swords blades from 7075 Aluminum. Aluminum blades are a mainstay of the film industry, and are also used in theater and other live performance fighting. You can only use aluminum blades with other aluminum blades, but if you give them substantial edge thickness they can last for years of hard use. As you've probably discovered 7075 is very easy to work compared to steel. It cuts, grinds and polishes with a lot less elbow grease.

I can't quite tell what stock thickness you have there, but usually the hardest thing about working with aluminum blades is securing the hilt. If you want the sword to ring when struck, it's best to put the hilt under compression with some kind of threaded pommel. If you don't care about sound, you can pin a pommel on any which way. Check out this page on my website for descriptions of a bunch of different methods for securing an aluminum blade, and the pros and cons of each: https://jesse-belsky-stageswords.squarespace.com/aluminum-blade-info

The other critical thing to know about working with 7075 T-6 (and this info may come too late as you've already begun shaping the blade) is that you can ruin the temper of the material by overheating it. This is only an issue if you plan to fight with it, of course. When grinding or cutting 7075 you want to keep it cool enough to handle with your bare hands. Technically I believe you don't blow the temper on 7075 until about 700º, but it can be hard to track that, and material can heat up fast especially at the edges and tip. Once the temper is wrecked, you can't fix it, and the aluminum becomes soft and weak.

Good luck, and let me know if I can offer any other advice!

T. Diamante · Posted: Wed 10 Aug, 2016 1:43 pm Post subject:

Thanks for the info Jesse! That hilt discussion is really helpful. I had heard mention somewhere about the temper issue, but didn't realize that it needed to be so cool. I'm not really sure how hot the blade got while I was shaping it; I was wearing gloves the whole time and my hands stayed cool. However, when I touched the blade barehanded immediately after, it was pretty hot. Not hot enough to burn me, just uncomfortably hot. I was grinding the blade on a belt sander, and worked my way all the down the blade with each pass and alternated sides, so I don't think the blade at any point got too much hotter after that, so I'd like to know your thoughts on the temper(or if there's a way I can check the temper without damaging the blade. Out of curiosity, how do your stage swords hold up with heavy contact? Are small gouges, burrs and dents normal? Or would that be a sign of a ruined temper on the blade? Again, thanks for the info!

Oh and, it looks like the stock was 1/4" thick.

Jesse Belsky · Industry Professional

Hmm. You may well have gotten it too hot, but you might get lucky. When I grind aluminum I cool it in water after every few sanding/grinding passes. One way your can perhaps test the temper is to compare it's hardness with a scrap piece of 7075 (like a chunk you cut off to make the tang or whatever...something that was never sanded). If you round over the corner along one edge, stick it in a vice and whack it with your sword blade, they should theoretically do the same amount of damage to each other (assuming the edge geometry is similar. Two pieces of the same material of equal hardness smack together, you would expect them to deform equally. If the blade takes a lot more damage, it's probably been softened.

In general, aluminum swords made from 7075-T6 can stand up to a lot of heavy use. The key is creating an edge geometry that's resistant to nicks. You want to give yourself a nice fat edge (a full 1/8" or more), and round it over so there's no corner to nick. Two such edges meeting each other will deform slightly and dent, but won't cause the kind of deep nicks that lead to blade breakage. Over time, the edge will pack down onto itself and from there on be pretty indifferent to impacts.

T. Diamante · Posted: Thu 11 Aug, 2016 12:36 am Post subject:

I'll try that test tomorrow if I have time. If I have indeed ruined the temper, then no harm. It would have been cool to have a stage combat ready sword but I never really planned on using it, so a wall hanger is just fine. That would also take away the issue of hilt assembly, since the ring of the blade would be irrelevant.

I have to say, I've never seen aluminum swords of the quality you sell. I've come across quite a few aluminum sparring and stage swords, and they've always looked to bulky, blunt and just "off", not at all like the ones on your site. If I may, what got you into working with aluminum and not blunt steel?

Jesse Belsky · Industry Professional

Thanks! My own sword background is in stage combat, and when I got the bug to try building something I was in graduate school and had access to a good metalworking shop, but no access to heat-treating facilities. So I thought I would start with aluminum, which I could fashion into a functional stage blade with no forge, oven, etc. Also, it's much easier to cut, grind and file than steel, so it seemed like a good place to start.

I do my best to make the AL swords look and feel real. The audience has to believe in them, but so does the performer. You can make an aluminum sword out of unground flat bar and it will still be light enough to wield, but i can't believe in it as a weapon. That works fine as a trainer for HEMA, but not for stage/film production.

T. Diamante · Posted: Wed 17 Aug, 2016 10:44 am Post subject:

I performed the test to check tempering, and there was a noticeably more damage to the blade than the piece of stock I tested it against. I've since more or less completed the sword and scabbard(images below). It's been a pretty interesting learning process, and several mistakes were made.

Firstly, I made the guard and pommel from leftover aluminum stock, which turned out to be a significant error on my part. The guard and pommel are not nearly heavy enough to counter balance the blade, and this is only compounded by the fact that I made the pommel too small to begin with. So while the sword weighs only about a pound and a half, it feels remarkably heavier as the center of balance is about nine inches in front of the guard. It was only after this mistake that I realized that aluminum blades are typically still mounted on steel hilts. The grip feels a little too fat for me, although I do have relatively small hands and I'm sure it would feel fine for someone with larger hands.

As for the scabbard, I decided to go with a coreless design. While it does look a little sleeker and holds the blade really nicely(it can be turned upside down without falling out, but glides smoothly out of the scabbard) I found that the all leather design has a mind of its own, and doesn't like to line up perfectly, resulting in an off center stitching line, though this could also be a measuring/cutting error on my part.

Despite these flaws, I'm still mostly happy with the piece. Since the temper was ruined from the start, the sword has been destined to become a display piece, so I'm not to upset about the balance issues. I'd love to hear any comments you have about it. I'm definitely interested in doing another one, hopefully fixing those issues.

Thanks!

Jesse Belsky · Industry Professional

A very good first effort! I look forward to seeing your next piece. Don't be afraid to copy dimensions and proportions shamelessly until you get the hang of things.
good luck!

Lafayette C Curtis · Posted: Tue 20 Sep, 2016 2:28 am Post subject:

OK, so going off on something of a tangent, can anybody chime in with experience about the malleability of aluminium? I know customs cars sometimes involve extensive manual work by panel-beaters so some aluminium alloys are clearly malleable, but what about the ones that are suitable for swords? And what about thinner stock for armour? Are they easier or harder to shape with the hammer than steel? And does it mostly involve cold work (with periodic annealing?) or hot?

T. Diamante · Posted: Tue 20 Sep, 2016 11:53 am Post subject:

Lafayette, I'm sure Jesse can probably answer this question better than I can. My experience with forming aluminum is pretty limited, but in the sword build I completed I did bend the crossguard slightly upward and peened the tang over. The peen was very thick but much easier to cold work than steel. As I understand it aluminum work hardens and in order to anneal it, I'm under the impression that you would most likely ruin the temper. However in components where the temper is less important, like the crossguard and pommel, it may be possible to do more complex cold forming. I have zero knowledge of working with sheet aluminum.

I hope this helped at least a little, good luck with any future projects you do!

-Tomas

Ray J · Posted: Sun 10 Dec, 2017 2:56 pm Post subject: Material and cost

Hi guys. Love this thread. I have been lurking for quite a while and I am really interested in making my own sword.
I have access to a small shed and backyard porch, so no heat treating for me. I don't want anything with a cutting edge anyways. So I was thinking about making an aluminum blade or an untempered steel blade. I have made wooden ones before. I was wonder about the preferred material and the cost. I have seen that 7075 T6 costs quite a lot to obtain a stock suitable for a blade. About $70+ if I remember correctly. Steel or other types of aluminum may be the cheaper alternative in this regard. So where do you get your material? And what size stocks? And what material other than 7075 is good for training/horsing around?
Thank you so much.