Response

Welding

Being a welder, this welding article has incorrect information in it and it has bothered me for years. Making Turbo Manifolds, Part 1

It says, "The welding can be done by MIG or stick. Stick (arc) welding allows the selection of a high-strength electrode to suit the application – in the case of the manifold shown here low hydrogen rods were used which are both very strong and also reduce the chance of hydrogen embrittlement."

This is an EXTREMELY mis-representing statement. Hydrogen embrittlement in a weld is from water contamination from moisture having been absorbed into the flux of electrods. This is NOT a problem with GMAW (mig) welding. It is a problem with flux welding - SMAW (stick), FCAW (flux-core arc welding, ie flux mig), and GTAW (tig) using fluxed rods.

It is also misleading because you are applying that gmaw welding uses only one wire for the process. All welding processes have more welding electrode & filler selections than you can shake a stick at. ALL welding processes easily allow the selection of the correct electrode and filler material.

It would be nice if you could rewrite some of the article to actually reflect welding. Some of the other welding articles have fairly bad information them as well.

Brandon
United States

We don’t agree that the article is misleading. That one reason hydrogen embrittlement occurs is as a result of moisture is irrelevant – it is addressed in arc welding by using low-hydrogen welding rods, as stated in the article.  As to the implication that MIG welding uses only one type of wire, in the real world that’s effectively the case – we’ve never seen a MIG welder change the wire to weld a turbo exhaust manifold. Of course the welding wire can be selected based on the specific application, but in exhaust shops it doesn’t happen.

Top Books

Thank you for the essential 10 books list (see The Ten Must-Have Books) - I've been looking for the ISBN of Manufacturing engineering and technology for about three years without being able to confirm it was the right book . ( I've two nice books that are similar but not it as a result of error) Typically I loaned it to someone and it never came back- sigh, at least it's still being used.

I would if I may add one other to your list "racing and sports car chassis design by Costin and Phipps  though it may be hard to get.

BTW you online magazine is the ONLY online publication I have EVER paid for directly. ( but I'm so glad I can now point others to it without them passing it up as it subscriber only.)

PS I'll send you some pics of the tandem hyper miler when it's a little further along. Tubeframe only just completed lots to go.

Stephen Flood
Canada

As mentioned in More books to read, we wouldn’t put the Costin and Phipps book in the same class as the cited titles.

Nickel Bronze Brazing and Chrome Moly

I stumbled on your site while surfing, what I have read so far is very impressive. I am a backyard car builder who is always looking for more knowledge to improve my building skills. to date I have built one car and modified many others. I have just read part 2 lightweight vehicles (see Building Ultra Light-Weight Tubular Frame Vehicles, Part 2) where you brazed a 4130 steel frame. I have also just read a motorbooks book by Richard Finch called Performance Welding , where he claims that welding 4130 by brazing causes cracks. I would be intersested to here your comments.

John Milsom
New Zealand

Yes we’ve heard the book quoted as saying that – but based on the experience of literally hundreds of brazed joints, and the type of failures that have been experienced in some of those brazed structures, it’s something we utterly reject. However, it may be possible by using poor techniques to achieve that outcome eg by quenching the hot steel, or overheating it in the first place!

Turbo’d for Torque

Recently read the article 'Turbo'd for Torque'. I have a 2005 Subaru outback 3.0R, with mods limited to MRT fitted stabilisers, Powerchip ECU & K&N airfilter. It's a sporty little motor that loves a windy mountain road. But I need MORE!!! Can you put me in touch with someone in the Newcastle/Central Coast/Sydney region that fully appreciates the point Julian Edgar makes in this article?

In the mean time I look forward to more great reading on all things auto. Keep it up.

Any competent workshop should understand the concepts covered in the article.