I've been intrigued by the SIG and Q cans with their tubeless designs.

Does anyone know how they are put together and if it is even feasible as a DIY?

They're CNC TIG or laser welded

You can do it if you have a lathe and a decent TIG.  It's how all of my rifle can cores are put together, and a couple I have that are tubeless designs

My God that is a work of art

Wow, awesome! Do you have more pics of your work?

I saw on a SIG video where they show a snippet of a suppressor being built.

Appears like they stack the baffles and caps together, drop it in a press to squeeze them together, then it goes to get welded.

I saw Q had a welding set up that appeared to be very small able to be placed on top a desk. Any idea if this is a commercial off the shelf item or a custom built rig?

Of course!  Lol.  Unfortunately, a lot of them were on my last phone, which died beyond recovery of anything in it.

The one above was a stubby .30 cal F1 can I recored for a local deputy.  Only 7 baffles, but it worked out pretty well for the length.  Before welding:



There's more than one way to skin a cat.  I'm planning to build a variable speed power unit to rotate the baffle assembly, but at this time still do it manually.  I use a rotary indexer to hold a rod which aligns the baffles



Each baffle has a stepped shoulder which fits snugly into the baffle behind it.  Basically self-aligning as long as they're under tension, but still have to watch for distortion when welding.  I tack each baffle every 90°, then do the circumferential welds, letting it cool and re-tightening the nut on the rod before each weld.  The front cap is last, and the stack comes off the fixture and goes back in the lathe to make sure the face is true before welding the cap on.  Most of the time I cut the threads on the front cap after welding.

Amazing. Thanks for the detailed response!

Nice welding job!

Strongly consider a pedal type switch on the rotary welding chuck along with a potentiometer to control speed. It makes a huge difference, I've found.

Interesting, taggy.

Here's one I did





Here's a vid of the welding and rig I made.

This is awesome. What are the baffles made of?

This is basically what I went from. I revised a tad, but not too much.
A centerfire can doesn't need to be serviced. Other than trying it out on my 22lr, bolt rifle, a couple of times, it lives on my 10.3" carbine.

The entire thing is from 17-4PH

Ok, I misunderstood. Sure. No reason the end cap couldn't have threads. Same goes for the mount. I executed it the way I did simply because it was made specifically to live on that particular carbine.

I could see another option, whereby you make a welded stack that slides into one of the modular tubes you already own. Your mount and end cap options would already be available. Obviously, this wouldn't have the same weight saving benefit, but I was just throwing examples around.

I think it ended up being 6.2ish and weighs 16oz. I know I could have thinned some areas out, reducing weight, but 16oz isn't heavy and it was built to be used.

Hand held speed control is the plan.  Trying to run two potentiometer pedals at once is a good way to change the thing you didn't intend to!

I used a PWM (pulse width modulator) for control of the motor. It's a small, 9VDC powered, gear reduction motor. I further reduced the ratio with a small drive gear and large final. I got it as low as a 1/2 revolution per minute.

I made a fixture to hold the torch using a magnetic indicator base.
I align the torch, turn it on, flip the motor switch.
A 4" piece of welding glass is fixed above so the weld can be observed.

The welding rig's base is a piece of SS, deep strut channel.
I keep the mag base touching it and the electrode square to the work.
Once the tip distance is set, I can just slide the mag base down to the next weld and be ready to go.

If I were to do this for production, I'd probably get a cheap and/or used lathe. Nothing special. Just a live center in the tailstock and the torch attached to the carriage.

Oh, that makes sense. I don't use a pedal when I use TIG, I've always preferred the button style. Plus, a lot of the time I'm using the rotary welding fixture, I'm using oxy/acet.