Best tool to shorten stainless bolts?

[GoldenStreak]

Milwaukee M18 Brushless threaded rod cutter?

 

[167149]

Milwaukee M18 Brushless threaded rod cutter? View attachment 414354

those work well with mild steel not so sure about stainless, have used the 24v makita coldsaw for rod cutting and was surprised how clean the cut was along with how easy to just pop a nut on after the cut, once again not overly sure how a cold cut works with stainless, One question/ query I do have though, 304 and 316 are both non magnetic how is it then after cutting with a hacksaw you can clean up the cut deposit with a magnet........ yeah asking for a friend

 

[gewoon ik]

bolts are made from chinesium. Looks like 316

 

[Israel Hands]

Conclusion:  I took y'all's advice, and when the McMaster Carr guy came by our business, I bought a box of 50 bolts of the right size for $16.10.

 

[IStream]

You could've spent $160 and it would still have been worth it.

 

[DDW]

316 can become slightly magnetic, from welding or cold working (sawing is cold working). EVERY 316 fastener in the US is from China, can't get domestically sourced anymore (well you can get them custom made for about 100x the price). Most 316 tube and plate also from China. For awhile after US sources dried up, I could get European made fasteners, not anymore. In your average SHCS, the Chinese ones can be identified by the head not being concentric with the shaft, and the socket drive not concentric with either. 

 

[CaptainAhab]

316 can become slightly magnetic, from welding or cold working (sawing is cold working). EVERY 316 fastener in the US is from China, can't get domestically sourced anymore (well you can get them custom made for about 100x the price). Most 316 tube and plate also from China. For awhile after US sources dried up, I could get European made fasteners, not anymore. In your average SHCS, the Chinese ones can be identified by the head not being concentric with the shaft, and the socket drive not concentric with either. 

The vast vast vast vast vast majority of stainless comes from Taiwan and is really good quality . The US setup stainless manufacturing there in the 1980’s, before that stainless was expensive. Chinese stainless is relatively new. Most products are marked with the alloy 304 or 316 and the country of origin. Beware of Chinese 302. It’s magnetic and rusts quick. 
 

 

[DDW]

The vast vast vast vast vast majority of stainless comes from Taiwan and is really good quality . The US setup stainless manufacturing there in the 1980’s, before that stainless was expensive. Chinese stainless is relatively new. Most products are marked with the alloy 304 or 316 and the country of origin. Beware of Chinese 302. It’s magnetic and rusts quick. 
 

Perhaps in Australia. In the US, any box of fasteners must be marked with the country of origin. Most SS fasteners are PRC, some are Taiwan. Same with tubing and plate. I'd agree that the Taiwan fasteners are typically a little better quality than PRC, but well below the US and European sources that used to be available. 

Aluminum is another product that is coming mostly from China and Russia. The Chinese stuff is typically horrible quality, the Russian not much better. I can still specify "US made" aluminum from my supplier, the cost is about 50% higher but it is well worth it. Machines and anodizes better, and usually tests to higher yields. 

 

[Raz'r]

I spent 4 hours last saturday cutting off bolts at the nut end. Tried a sawzall with the right blade, tried a grinder, hacksaw.

What worked, although it kicked out a shit-ton of dust, was a Dremel with a 90 degree attachment, a quick change arbor the fiber reinforced cutting wheels.

I could cut 4, 5/16" bolts per wheel or 2,  3/8" bolts. Had a face guard and dust mask.

Damn cut ends falling into your shoes by the ankle were hot.

The sawzall and full grinder just couldn't get in flush when maneuvering around all the stuff in a boat.

 

[CaptainAhab]

Perhaps in Australia. In the US, any box of fasteners must be marked with the country of origin. Most SS fasteners are PRC, some are Taiwan. Same with tubing and plate. I'd agree that the Taiwan fasteners are typically a little better quality than PRC, but well below the US and European sources that used to be available. 

Aluminum is another product that is coming mostly from China and Russia. The Chinese stuff is typically horrible quality, the Russian not much better. I can still specify "US made" aluminum from my supplier, the cost is about 50% higher but it is well worth it. Machines and anodizes better, and usually tests to higher yields. 

I’m American. I moved to Au 10 years ago. Chinese stainless wasn’t that common in the US 10 years ago. Unless you were looking to buy the cheapest fasteners available. Everything is marked by law here as well. 

 

[CaptainAhab]

those work well with mild steel not so sure about stainless, have used the 24v makita coldsaw for rod cutting and was surprised how clean the cut was along with how easy to just pop a nut on after the cut, once again not overly sure how a cold cut works with stainless, One question/ query I do have though, 304 and 316 are both non magnetic how is it then after cutting with a hacksaw you can clean up the cut deposit with a magnet........ yeah asking for a friend

“The most popular stainless steel is Type 304, which contains approximately 18 percent chromium and 8 percent nickel. At room temperature, the thermodynamically stable crystal structure of 304 stainless steel is bcc; nevertheless, the alloy's nickel concentration, as well as the small amounts of manganese (about 1 percent), carbon (less than 0.08 percent) and nitrogen (about 0.06 percent), maintains an fcc structure and therefore the alloy is nonmagnetic. If the alloy is mechanically deformed, i.e. bent, at room temperature, it will partially transform to the ferritic phase and will be partly magnetic, or ferromagnetic, as it is more precisely termed.”

It’s from some Scientific American article. 
 

I would also guess that the intense heat from the friction of cutting cooks off the alloys, leaving more iron exposed. This would add to the work hardening from the cutting. 

 

[ryley]

I would also guess that the intense heat from the friction of cutting cooks off the alloys, leaving more iron exposed. This would add to the work hardening from the cutting. 

yup, which is why it is recommended that after cutting stainless you re-passivate it. I use citric acid. I've never done it on the cut ends of bolts, but definitely on bigger pieces like shafts and stainless plates.

 

[DDW]

Most 304 is very slightly magnetic, including fasteners, plate, tube. Most literature and lots of experience prove this. Perhaps the author of the SA article spent too much time in the lab and not enough in the shop. Most 316 isn't as delivered, but some welding or cold working can make it so, usually less than 304 in its as-delivered state. 

My understanding is that excessive heat doesn't burn off any alloys, rather it can participate carbides and/or change the crystalline structure from austenitic to martensitic. It can be changed back (and the carbides driven back into solution), but that requires a specific heat treatment - passivation doesn't do it. 

10 years ago I could still get good quality non-Asian SS fasteners. This began to change about then and the last US or European fasteners I got were about 5 years ago. You can still get NAS or some other specialty fasteners that are US made. I'd be happy to pay 2 or 3x the price for US (on any high quality) fasteners, if I could get them. 

 

[Irrational 14]

The vast vast vast vast vast majority of stainless comes from Taiwan and is really good quality . The US setup stainless manufacturing there in the 1980’s, before that stainless was expensive. Chinese stainless is relatively new. Most products are marked with the alloy 304 or 316 and the country of origin. Beware of Chinese 302. It’s magnetic and rusts quick. 
 

In our experience, 304 is not so great compared to 316. Over time, the 304 corrodes (rust) much more and heads fail on the hi load stuff.

 

[CaptainAhab]

In our experience, 304 is not so great compared to 316. Over time, the 304 corrodes (rust) much more and heads fail on the hi load stuff.

At the very least the 304 stains much easier in a salt water environment. I think of 304 as construction grade(decking screws) and 316 as marine. We do have some trouble in AU getting all of the boating(inch scale) fasteners in 316. 
 

It’s another of those weird AU not metric industries. We primarily use inch fasteners on boats. The metric fasteners are used for some Ronstan fittings or some electrical parts. Everything else is held on with 1/4-20’s. Just like the States

 

[CaptainAhab]

Getting back to cutting bolts. My mentor who happens to be a now retired composites/structural engineer at the Boat, liked the vise grips.

We would install the jib tracks with 1/4” aluminium backing strips. 1/4-20 flat head machine screws and nylocks. After torquing we would grab on with the vise grips and lightly wiggle the bolt until it work hardened and snapped. Take a file and dress the burr. If you got a ton to do this is very fast. 

 

[gewoon ik]

Aluminium and stainless mixed. Good way of making sure you have jobs on board.

 

[SloopJonB]

Aluminium and stainless mixed. Good way of making sure you have jobs on board.

How would you mount Jib track?

Aluminium fasteners?

 

[Gissie]

The vast vast vast vast vast majority of stainless comes from Taiwan and is really good quality . The US setup stainless manufacturing there in the 1980’s, before that stainless was expensive. Chinese stainless is relatively new. Most products are marked with the alloy 304 or 316 and the country of origin. Beware of Chinese 302. It’s magnetic and rusts quick. 
 

When I was working in China the salesman would turn up with samples. Asked what the material was, he would ask what I wanted it to be. Happy to supply mil specs to any standard needed. :lol:

 

[DDW]

That reminds me of the Horse Cow, a long gone submariner bar near Mare Island. My friend ordered a Heineken. Completely deadpan, the barmaid asked, "do you want that in a Bud or a Miller bottle?"

The vise grip method described above is not going to make removing those fasteners easier, when the time comes. But I could see doing it on Other People's Boats.