Same! Gotta get the slicks on there soon.

 

On my manifold (not 4130) we had the standard cracking issues in the butt welds. I re-ground until there was actually a gap at each joint, as well as the 45* chamfer. Then we multi-pass TIG welded each joint. The first pass had to bridge the opening, so full penetration was somewhat guaranteed. Finally, the manifold has held up. Note: it is just a log.

I don’t know if multiple passes are legit on 4130.

On boiler tubes and pipelines, multiple passes are normal.

EDIT: Nope. No gaps, little chamfer for 4130. Miller Article

DNM

 

 

If you don't mind me asking here, i'm binge watching through your channel and have a question. You used a Coballt drill bit from I believe Grainger (Episode 4)? Were these the ones you were using and how well do they cut through stainless?
https://www.grainger.com/category/machining/drilling-holemaking/drill-bits/drill-bits-for-metal-plastic/hex-shank-drill-bits?attrs=Material+-+Machining%7CCobalt&filters=attrs&categoryIndex=4

 

I use these: https://www.grainger.com/category/ma...&filters=attrs

They last for quite a while in stainless or steel. Cobalt seems to last 3 or 4 times longer vs HSS bits.

Glad you're liking the channel!

 

I skimmed that. I will read over in depth in a bit. But good info I have not seen before, I appreciate it!

 

The trick to making bits last longer in stainless is slower speeds and a hell of a lot harder feed. Most stainless won't move heat very well and most will work harden. Very hard to do by hand, if you have a drill press I doubt you need anything too exotic.

 

Thank you! Enjoying the content quite a bit. Hardly anybody goes through the thought process behind what they do and actual implementation. I also picked a Rogue Fab HD600 as I want to mess around with creating a tubed front subframe. I look forward to seeing you use it later on.

I have an old drill press I got from a family member that goes down to I think 450rpm. I don't mind spending a bit more per bit if that means it'll last longer.

 

HSS Twist Drill Recommended Speeds, Feeds, and Point Angles

Might not be slow enough if you get into bigger diameter stuff. You really want to be 30-50 SFM, and that's ~230-390RPM with a half inch bit.

A cobalt will take more heat before it goes soft, but not that much. Maybe go cobalt for the bigger bits you can't slow down enough. Either way, HSS is going to work a lot better if you've got a rigid setup and a nice constant feed.

 

 

 

 

Have you seen the 1000:1 inverter duty motor swaps? I wouldn't be messing with anything else. You want torque? This is torque. Get a motor with encoder and do rigid tapping. There's ways to hook the CNC controller up to the VFD to have full control over the spindle.

https://www.cnczone.com/forums/bench...formation.html

 

I have not, but that sounds awesome. I will check that out tonight. A good motor with encoder would be the best for sure, I thought that would be too pricey though but maybe not.

 

I think it'll run you about a grand all in, but worth it in the end for sure.