quagmier

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About quagmier

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    Rose Hill, Kansas
  1. So what DID happen to him?

    Art, I remember Smokey's engine... Hotrod magazine did a story about it. Pontiac Fiero Iron Duke 4 cyl with a vaporizer. It ran the air-fuel mixture thru the vaporizer which used heat from the coolant or the exhaust (can't remember which)before going thru a turbo, this turbo made no boost except what was needed to keep the vaporized air-fuel mixture moving towards the intake valve. It claimed v-8 power levels, but don't remember the mileage quoted. It must have been between 1980 and Dec 1984 (when I joined the USAF and ended my Hotrod subscription). on edit, found this article: http://www.hotrod.com/articles/hrdp-1009-what-ever-happened-to-smokeys-hot-vapor-engine/
  2. x2, I've taken plenty of unnecessary risks in my day, lucky to still be here.
  3. bolts vs studs

    AK, you are correct about the angle of twist of a long fastener being another variable. Also, a torqued joint will relax and lose about 10% of the preload, another item to take into account. Yep, a stud or bolt is a very stiff spring, as long as the applied torque does not exceed the elastic limit it will return to its original shape. I don't remember what the Cummins manual says about re-using head bolts after the , because they are torqued to and possibly beyond the elastic limit (the point of yielding) - and are permanently deformed. I would be surprised if they recommended re-using them. On my engines, I chase threads with an oiled up bottoming tap. If it became hard to turn, or brought back a lot of chips I would investigate further. The threads need to be clean, and the threads need to be in good shape. Mike H, I don't know what to do in that case, its beyond my expertise. In airplanes we never tap threads, and we always toss structural fasteners that are disassembled, they are never reused. That gets very expensive for the owner especially when they are titanium or inconel, but the risk of failure is too high for re-use.
  4. bolts vs studs

    Ultimately a manufacturer is going to use the cheapest method that gives acceptable reliability. Their definition of "acceptable" may be based on performance (failure percentage in use), lab tests they have performed in house, however they define it. Most engines will use bolts for various reasons: cost, assembly time, fewer parts, etc, Bolts work fine for stock power levels. Navistar had some issues with early 6.0 L Powerstrokes because they didn't have enough clamping of the head to the block (only 4 head bolts per cylinder). These engines perform much better with larger diameter studs. And the 6.4 L Powerstroke can make a lot of power (much more than stock) before they have issues because they used larger bolts (still only 4 per cyl) and possibly some different assembly procedures. The Cummins 5.9 (1997 model from a Dodge Ram) uses a "torque to yield" method, where its torqued to a certain value, then rotated 180 degs further. Other manufacturers will use other methods that allow for automated assembly. Its hard to say what would let go first, the bolt or stud usually has a lot of thread engagement into the block, so a few threads can yield without issue. It gets even more complicated because now were talking fatigue initiation and fracture mechanics.
  5. Farmers only

    that's pretty funny "my wife isn't happy..."
  6. Interesting call from CNH today

    I think it would be quite the honor. My thoughts off the top of my head: It would probably not be started or warmed up for the entire time, consider that in your decision. It would be in a heated showroom, much better than an unheated storage shed (Jeff, I don't know anything about your storage, just an example). Also probably cleaned quite often. I might require some minimum of security to ensure people stay off and fingers don't touch or take. If they offer something in return - great. I think I would do it even if nothing was offered. But you may feel differently. Have a plan in case of emergency (health or financial) heaven forbid, and discuss with your insurance agent. I always like to know I have an out, so maybe upon written notification you would be able to remove item with 30 days notice or similar. Good luck either way!
  7. bolts vs studs

    ST, First, let me say: I've been a structural engineer for 24 yrs (on transport and small aircraft) and I'm the first to admit bolted joints are very complex with a lot of variables, I am no expert on bolted joints especially with preload. There are entire textbooks (Bickford is one I know of) discussing bolted joints. A little background info: The preload of a joint serves to reduce the fatigue load on the bolt or stud. With the clamp-up (ie initial bolt torque) the bolt sees little or no load from each ignition cycle of the engine (for instance) - leading to long life for the fastener. The bolt tension creates a cone shaped compression zone (aka frustum) in the head and engine block as shown in the figure, dark pink area (ref Shigley Machine Design). When torquing a bolt, some papers quote as much as 90% of the applied preload (me with my torque wrench) is going to fighting the friction (both in the thread-to-block and the bolt face-to-block) and 10% goes to stretching the bolt (the goal of preload). Still, knowing the amount of friction, the applied torque can be increased to apply the required preload to a bolt. Unfortunately, friction is a variable very difficult to quantify in the real world (me in the garage), there are a lot of sources for variability in the applied torque to a joint. Bolt or stud diameter tolerances, threading tolerances, corrosion or dirt, materials, zinc or other plating, lubricants used, torque wrench accuracy... The use of studs reduces the variability of the sources of friction. A company that manufactures the mating thread surfaces can ensure repeatable or good quality fit (as opposed to the engine block machining vendor and the bolt vendor for a OEM, yes they should both be making threads to spec, but...). Studs are also usually larger diameter (I say that based on the ARP stud vs Cummins head bolt in my 5.9 engine - photo below), and can't say studs are always larger). Larger diameter means a larger compression zone in the joint, and lower fastener fatigue load. Someone else mentioned it already - studs are definitely better if the joint is taken apart often. But they also complicate the removal of a part because it requires more room to clear studs (unless the studs are removed first, and your losing some of the benefit of saving the block threads - granted the block threads are not seeing the friction load from bolt torque, which helps). A note regarding fine threads: UNJ threads leave a larger remaining bolt diameter than course threads... another good fatigue detail. Rolled threads are also a much better fatigue detail compared to cutting threads, but few have that capability in their shop. Nuts are always cut threads, which is fine because the bolt transition from thread to no-thread is the critical fatigue detail of the joint. I hope that helps. I'm sure the ARP tech papers would be a better source for why studs outperform bolts. Andy
  8. This guy is a patriot

    I'm also a big fan, his album Town Line is a favorite with a couple versions of Country Boy
  9. What's Your Heritage?

    Dad's side is all Finn, not surprising for MN, I have dozens of cousins who still are 100% Finn. Mom's side is more interesting mixture: English, Irish, Scottish, Dutch
  10. Chickens massacred!

    I had not heard the term "fisher cat" before, so after a few minutes reading Wikipedia it shows their territory map including N MN and MI. https://en.wikipedia.org/wiki/File:Fisher_area.png Can't say I'd be surprised if they were in IA as well.
  11. Memorial Day---more than the start of summer!

    bitty x3 Great speech by Ronaldus Maximus
  12. Gonna cement the machine shed....

    I had mine poured back in Dec, wish I'd have gone with in floor heat like Dads706 mentioned...
  13. Tractor choices

    I'm originally from the Litchfield area of MN ... personally, I'd want a cab on my tractor. Thanks for your service and may the Good Lord watch over you.
  14. WOW some people!!!!!

    I can't see how he stays in business with an attitude like that, no matter what your cap says
  15. Veterans Day - The Holiday is Special

    It is foolish and wrong to mourn the men who died. Rather we should thank God that such men lived. George S. Patton Its tough to not mourn, though