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Stirling Engine Manual Lathe/Mill Assembly

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To obtain my manual machining certificate I had to machine a Stirling engine assembly from scratch on only manual machines. The Stirling engine can be powered by any heat source, and can run reliably with proper lubrication without producing any waste or pollution, by using heat expansion in a displacer cylinder to push air to the power cylinder.

Excluding fasteners (36)
the entire assembly consists of 28 pieces.
Excluding the cast bronze flywheel and precision ground drill rod, everything was machined from billet material.

The material type for the machined pieces include silicone bronze, C36000 brass, 6061 aluminum, graphite, 1018 mild steel, 303 stainless steel, and M1 high speed steel.
The tolerances for these pieces vary quite wildly, and can be separated into tight, medium, and loose categories.

Starting with loose tolerance components are the base and the bulkhead pillars.
The base is a sheet of 1/2" thick aluminum onto which all other components are mounted, sized and d…

MINI Won't Turn Over

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Ok, it's been happening often enough recently that I've decided to write an entry on it in the hopes that I can help out a fellow MINI enthusiast. One of the quirks of owning and maintaining a F56 MINI (it doesn't seem to affect the R53, pre-refresh R56, and only occasionally the refresh R56), has been more than annoyance to anyone who knows what I'm talking about. Here's the scenario: wake up, take a shower, eat breakfast, go out to the car park and low and behold, your R56 pre-refresh is inexplicably won't turn over. It happens mostly when it's particularly cold outside, but I've noticed lately it happens even when I put it in the garage. If you're like me, the first step is going to the forums. Head over to North American Motoring, get in a heated discussion about something else, then zero in on a few possible fixes. I decided the best method would be to start throwing parts at the problem. Thanks to all of the suggestions, this is what I've …

You spin me right round, Baby.

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Greetings Everyone! Steve with CravenSpeed here. I wanted to take a few minutes and introduce you to our latest product for the ND MX-5 Mazda Miata.We here at CravenSpeed love our ND MX-5 and developing new parts for it has always been a fun, eye-opening experience. Those folks at Mazda really know what they’re doing and every time we take something apart, we marvel at the engineering that went into a particular piece of it. However, it seems that there’s always going to be something that can be improved upon and the heavy factory pulleys are one of those areas that could use a little of the ‘CravenSpeed touch’.We have a fairly extensive history of making lightweight pulleys and they’ve proven to be a great way to recover some lost power from spinning the OEM crankshaft and accessory pulleys. This 3-piece kit consists of a crankshaft, water pump, and an alternator pulley. These lightweight pulleys are precision machined out of 6061 aluminum, so they’re perfectly balanced and true. If…

Boxer Rebellion

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I have to get one more historical (and on-going) project out of the way before I'll feel really caught up enough to talk about current product development. Here at CravenSpeed we fold about 150k boxes a year, and have I mentioned lately we do it all in Portland, OR? Doing this stateside means it costs us a pretty penny in labor for our thumbs-only origami efforts. Enter, the box folding machine. We've been working on this thing for about 2 years, off and on, mostly off. But now that it's in production, it's become a bit like a pet horse; we all love it because it works hard for us, and we also suspect that it's smarter than it lets on, but it is a hungry beast that needs to be fed constantly.          Before getting started, we did some time trials and we discovered that a person can fold one of these boxes in 7 to 10 seconds, which is much faster than it works out to in a 8 hour shift because people can't (or won't) keep that pace for an entire shift. For …