Move Over Aluminum: Cast Iron for the Home Foundry

When it comes to choice of metals that can be melted in the home foundry, it’s a little like [Henry Ford]’s famous quip: you can melt any metal you want, as long as it’s aluminum. Not that there’s anything wrong with that; there’s a lot you can accomplish by casting aluminum. But imagine what you could accomplish by recycling cast iron instead.

It looks like [luckygen1001] knows a thing or two about slinging hot metal around. The video below shows a fairly expansive shop and some pretty unique tools he uses to recycle cast iron; we were especially impressed with the rig he uses to handle the glowing crucibles from a respectful distance. The cast iron comes from a cheap and abundant source: car disc brake rotors. Usually available free for the asking at the local brake shop, he scores them with an angle grinder and busts them into manageable chunks with a hammer before committing them to the flames. The furnace itself is quite a thing, running on a mixture of diesel and waste motor oil and sounding for all the world like a jet engine starting up. [luckygen1001] had to play with the melt, adding lumps of ferrosilicon alloy to get a cast iron with better machining properties than the original rotors. It’s an interesting lesson in metallurgy, as well as a graphic example of how not to make a flask for molding cast iron.

Cast iron from the home shop opens up a lot of possibilities. A homemade cast aluminum lathe is one thing, but one with cast iron parts would be even better. And if you use a lot of brake rotors for your homebrew cast iron lathe, it might require special handling.

Continue reading “Move Over Aluminum: Cast Iron for the Home Foundry”

Re-Engineering The Ford Model A Engine

Over the nearly a quarter century since the Web has been in existence, there have been various websites and projects in the field covered by Hackaday that have done the rounds and captured our attention for a while. Some have turned into major projects and products, others have collapsed spectacularly, while many have faded away and been forgotten.

It was one of those “I wonder what happened to… ” moments that prompted a search for just such a project that did the rounds a little at the start of this decade. Re-Engineering the Model A Engine is [Terry Burtz]’s project to take the Ford Model A engine from the 1920s and re-engineer it with the benefit of some upgrades to increase its longevity and reliability. The new engine would look identical to the original unit, but would feature modern metallurgy, a re-engineered crankshaft with up-to-date bearings, a pressurised lubrication system, and some cooling system modifications.

The web site has a fascinating technical description and history of the Model A engine, along with a detailed examination of the proposed upgrades. There is a long list of project updates, but sadly work stalled in 2015 due to difficulties finding an iron foundry that could cast the blocks at an affordable price. It’s a shame to see a promising project get so far and fall at this late hurdle, is it too much to hope that among the Hackaday readership there might be people in the foundry business who could advise? It’s quite likely that there would be a queue of Model A owners who would be extremely grateful.

If you think you’ve seen some veteran Ford action here before, you’d be right, but only to a point. Meanwhile where this is being written a similar project for a 1950s Standard Triumph engine would be most welcome.

Books You Should Read: Engineer to Win By Carroll Smith

One problem with engineering education today is a lack of experimental teaching. Oh sure you may have a project or two, but it’s not the focus of the program because it’s hard to standardize a test around. Typically sections of the field are taught in a highly focused theoretical course by a professor or graduate student with a specialization in that section. Because classes treat individual subject areas, it’s entirely possible to get a really good understanding of two pieces of the same puzzle, but never realize that they fit together to make a picture. It’s only when a freshly minted engineer gets out into the real world that they start to make the connections between seemingly disparate fields of knowledge.

This is why Carroll Smith’s book “Engineer to Win” is so good. He spent a lifetime as a practicing engineer in a field where a small failure could mean the death of a friend. So when he set out to write a book, he wrote a book that related everything needed to properly conceptualize and solve the mechanical engineering problems in his field.

One warning though; the book is not for the faint of heart. If you want to learn something difficult well, then this is book for you. Carroll skips the comforting analogies and gives the information exactly. It can get a little dense, but he makes the assumption that the reader is there to learn and, most importantly, understand. This takes work.

2016-08-01_02h06_34For example, you can’t really understand why a rolled bolt is stronger than a bolt cut on a screw machine until you understand how metal works on a crystalline level. The same goes for metal fatigue, brittle fractures, ductile failures, and all the maladies that metal can suffer. The difference between an engineer and a technician is this deep understanding. Otherwise the equations learned are just parts in a toolbox and not paint on an artist’s palette.

This is why the first half of the book is dominated by all things metallurgical. The book starts with the simple abstractions of the crystalline structures of metal. Unlike my materials class in university, it maintains a practical bend to the presentation of the information throughout the whole process. For example, it moves on to what all this practically means for metals undergoing stresses and failures before it launches into a (short) digression on how metals are made and their history.

However, if racecar plumbing is your thing his treastise, "Carroll Smith's Nuts, Bolts, Fasteners and Plumbing Handbook" is also fantastic.
However, if racecar plumbing and fasteners are kinda your thing, “Carroll Smith’s Nuts, Bolts, Fasteners and Plumbing Handbook” is also a fantastic read.

This first half of the book touches on non-ferrous metals and their proper use as well. After that comes some of the best explanations of metal fatigue, fasteners, and metal bonding I’ve ever read. When the failure of a joint causes a mechanism to fail in a toaster that’s one thing, but when it fails in a racecar people get hurt. Carroll is very exacting in what constitutes a forgivable oversight in engineering, and what does not.

Once the book has finished conveying a working understanding of metals and fasteners it seems to fracture into a pot-luck of different racecar-related topics. During my first reading of the book I resisted this strange turn of events. For example, I didn’t really want to read about racecar plumbing in the eighties, or what kind of springs and aerofoils Carroll likes. However, when I reread those sections in a more focused manner, I realized that many of them were teaching the practical application of the knowledge learned in the previous chapters. How does the metal make a good spring? Why is one kind of plumbing better than another?

Importantly, the anecdotes at the end of the book impart an understanding of the importance of professionalism in engineering. What is the true responsibility of an engineer? He teaches not to take the trust others place in your skills for granted. He teaches to trust in the skills of others. The book teaches humility as an engineer. He shows the kind of person one can become after a lifetime of earnest study in their craft.

Thanks to reader, [Dielectric], for recommending the book to me. Also, from the bit of research I’ve done, the older motorworks edition is generally considered to have better quality reproductions of the diagrams than the newer printings of the book.