And speaking of studs, the original subject of this thread, how does one safely remove a tight stud from a casting? I just used Vise-Grips to unscrew one from my cylinder head. It worked, but the teeth scratched the daylights out of the stud body. Is there a tool that clamps down well on smooth cylindrical objects, without slipping and gouging?

Tom.

There are special tools for removing studs without damage even more special one for wasted studs! but if there not overly tight you can use the double nut method. put two nuts on the stud and tighten one against the other then undo using the lower nut keeping the top nut tight against the lower

The studs they had used were lengths of threaded bar of the type you would find in a hardware store – and this was an airworthy aircraft!

Bruce

Or not airworthy in fact!!

Love the truncated Swastika on the tail PC avoidance at it’s best……………..

minimans – show me a museum that does not have airframes that are in store and awaiting work on them, been to the RAF Stafford store recently ?

http://www.midlandairmuseum.co.uk/news.php

Sorry I wasn’t suggesting anything by my comment I thoroughly enjoyed my visit to the museum on my trip home to England! In fact as I said to one of your volunteers the “back” of a museum is always my favorite place to visit where the ladies awaiting there turn for restoration usually live! I also bought over $150 worth of books from the excellent cafe/gift shop.

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With a supercharger, the boost obtained is a function of the throttle opening, the throttle usually being positioned before the impeller, the boost control limits the maximum opening to the set boost pressure, at sea level this may be, say, 50% throttle, the boost control allowing the throttle to gradually open and let more air in as the ambient pressure drops with altitude, until the full throttle height is reached.
No compressed air is wasted in this way because the more you close the throttle, the less work the blower has to do, just like a vacuum cleaner motor speeding up when you cover the inlet.

The reason two speeds are employed is because engines work at maximum efficiency with no throttle to restrict the air intake, so at lower altitudes, a lower speed blower runs with a greater throttle opening, plus of course, turning the impeller more slowly will use less energy, because the drive ratios are high, in the region of 6 to 9 times the crankshaft.

Pete

Thanks Pete!! thats the most clear explanation of boost control I’ve ever read for a layman to understand……………

Jingle bells with Merlins? this is not a Merlin but gives the general plan……………….. http://www.telegraph.co.uk/motoring/motoringvideo/9718300/Japanese-driver-plays-Jingle-Bells-with-his-car.html

Why am I not surprised that Americans are behind this? Clearly still feeling a bit sore that they didn’t produce an aircraft as iconic as the Spitfire, they produce this mutt and try and belittle the real deal? A weird mentality. Imagine that a UK builder built P51 replicas with a lighter body and a more powerful engine, would the yanks take to it so kindly? I doubt it.

What! I see no belittling going on here? just a statement that it goes better than a real one, so what? maybe it does maybe it doesn’t it’s not like he’s trying to pass it off as anything but a replica……………………And as to the P51 comment we did do that remember we replaced the Allison with a Merlin and I don’t hear to many Americans giving barbed comment’s about us doing it???

I saw a full size Allison powered Spitfire at Oshkosh many years ago maybe one of the ones mentioned? I remember being confused as it came on final as it looked like a Spit but certainly didn’t sound like one! when I got a closer look you could see straight away that it was a replica as it looked like it had been flush riveted all over. The wings were particularly smooth. I have some photo’s somewhere I’ll dig them out and post some.