hybrid AlBr/ Al torch

[DrafterDan]

Okay, not liking the route of failure, I decided to complete a torch from a big oops. I had started an AlBr/ C954 torch, and then managed to cut a land too deeply and the threaded tailcap section landed in the chip tray...

Here it is, literally two minutes from a big jaw-drop

That nice tailcap section? Gone.
But after a bit of time and a glass of wine, I decided to try an experiment. Fix it with Aluminum!

What the heck do I call this? Albral? (aluminum bronze/ aluminum), I dunno. I had a scrap of 6061, which I don't like lathe-ing, but made a tailcap anyway. Then I soldered it onto the body. Seemed more electron-friendly than epoxy.

A couple days ago I did end up stopping by the shop (which is on the other side of town from my house) to work out a bezel.

The overall plan is to use my 20mm left-over reflector from my Convoy S2+ project (I turned that into a triple). I think I'm using reflectors more than triples in my most recent builds.
Looks like a good start, no? NO! I read my calipers wrong and cut the lens end hole .10" wider than it should be. Ah well, I'll chalk it up to another threading exercise.

Since I've been thinking about this, do you handy folks run in the threading tool with the Zed of the cross-feed, or do you control the depth with the compound set at 30°? I have done some experiments with the cutting tool hitting at 90°, and as it sits right now, it feels better when contacting at 30°

so, the next time I hit the shop, it's another hour hogging out aluminum, 7075 this time because I planned ahead.
Maybe I can get this sorted out before the weekend is over

~D

 

[Thetasigma]

Interesting solution, since solder doesn't typically stick to aluminum, did you use it to essentially create a press-fit?

On a threading note, I have used the cross-slide for threading as I had poor results with compound threading when I started, but I suspect that was the machine and lack of experience. I get good results, but it should be noted I cut fine threads in stuff no harder than 6AL-4V titanium at the hardest. Cutting harder or coarse threads on a relatively small lathe with the cross-slide can cause drunken threads, where the threads actually move the carriage around resulting in an uneven cut, whereas compound threading maintains forward pressure on the leading edge, mitigating that possibility.

C642 below, similar properties to C954, but much nicer to cut.

 

[DrafterDan]

TS, you'll have to re-upload that image, now that you've peaked my curiosity. I've not heard of C642, but it sounds interesting. I really didn't have any issues with the C954, other than it loves to work-harden if you're timid on the feed speeds....

Pretty much all threads I've cut are 20 tpi, so nothing too coarse. My first pass is about .015" and then shallower cuts as I work towards final depth. But that is measured on a 30° angle, so a ten thou cut turns results about .008"-ish. I've been cutting the threads to about .040" overall depth.

I did thread the AlBr, and the aluminum tailcap, but felt that soldering it would be beneficial. I got a nice flow, so I feel confident the solder was a good addition.

More experiments to happen this weekend.

 

[Thetasigma]

I think that fixed the image, if not here is a link, https://photos.app.goo.gl/T4m48YQWVoDUBpJo8

I think my favorite bronzes are C642, and of course C863 or Manganese Bronze. The Mn-Bronze is some tough stuff, but notably more difficult to machine than C642. The nice thing about C642 unlike C954 or C863 is it is supplied in a smooth mill finish instead of the rough continuous cast.

 

[DrafterDan]

I see the image now TS, thanks! Plus, i've been eye-balling some C642 now...

 

[Anglepoise]

Below is a photo showing the 4 methods of in feed when threading. Which one you choose will depend on how fine or course the threads to be cut are. Photo from the Sandvic.folk.

 

[Anglepoise]

This is my most used setup. Compound set to 29.5 degrees. Infeed by compound.
Depth of thread measured by dial indicator.
See next photo.

 

[Anglepoise]

 

[Thetasigma]

This is my most used setup. Compound set to 29.5 degrees. Infeed by compound.
Depth of thread measured by dial indicator.
See next photo.

Well hey, that is a nice setup, love those tool posts too, but have never seen a good place to buy one.