Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

Search results for query: *

  • Users: gbent
  • Order by date
  1. gbent

    Will Discipline Help?

    What's the problem? Are you a control freak? Tight disipline does not mean a good shop, or a good work environment. The shop is probably operating the way the owner likes it.
  2. gbent

    Replacement of existing foundation

    If they exist in your area, contact a house mover. Move the house out of the way and construct the basement without any obstructions. Your lot size may not allow the house to be moved out of the way, however.
  3. gbent

    hardened valve seat installation

    Find a new shop. While not a job for a newbie, it can be done with 100% success. I have also completely rewelded and remachined seat pockets successfully to repair damages. And no, you can't make absolute statements about the amount of interference needed without considering the size of the...
  4. gbent

    The price of 134A

    What is driving the price of 134A? Last year I bought a couple af cases for about $4.00-$5.00 a can. Today I got sticker shock from the parts store at 14.00 a can, and they said 20# tanks were $300. Is this price jump permanent, or just a short term shortage? Anybody have any reasons?
  5. gbent

    General information on 100+ year old wood

    jimzpe: Given the time frame and location (can you be more specific on location? There is a lot of difference across Kansas.) I would say the wood is Cottonwood. It was greensawed on or close to location, and nailed up green. Cottonwood takes a nail good when green, but when dryed is damn...
  6. gbent

    drilling bolt circle

    I wouldn't expect very good accuracy from a 3 jaw chuck 10" from the face of the chuck, unless it was a very good chuck. Most chucks I've seen on mills came off lathes because they were worn out, and then found a home on a mill. Your set-up is hard on the chuck too, as the fine chips tend to...
  7. gbent

    Engine efficiency maps

    Thanks, Greg. The graphs are interesting. It would be nice to know more about the engines, such as was the SI EFI or carburated, open or closed loop? Was the CI turbocharged? Does anyone have access to American engine data? An EFI small block chevy and a pick-up type diesel would make an...
  8. gbent

    Heat Treatment before vs after Machining

    With any heat treated part, the heat-treater is an important part of the equation. You will need to work with them to develop a procedure, and then make sure they follow it. There is a lot of art to heat treating when low distortion in needed.
  9. gbent

    Engine efficiency maps

    I have seen many engine efficiency graphs for engines at full rated power, but I don't think I have ever seen a set of graphs showing engine efficiency vs. RPM for different constant engine loads. I would like to see information for both SI and CI engines. This would help show the best RPM for...
  10. gbent

    recommend a torque engine for towing and high MPG

    If this could have been done effectively with gasoline, there wouldn't be so many diesel pickups around. If you must use gasoline, try to rent or borrow (or a long test drive) a Chevy/GMC with the 8.2 and see how you like it. If it is acceptable, try to find one in a salvage yard. The no...
  11. gbent

    Cylinder liner honing

    Cylinder bores are usually honed any time new rings are installed. If the existing bore geometry is acceptable, this may be only a "touch hone" to roughen the surface for the new rings (origional size) to seal. If the bore geometry is worn enough, the bore is oversized to the next available...
  12. gbent

    Repair of Forming Cracks in Structual Steel

    I would not weld without knowing the application and stresses. If you weld perpendicular to tensile stresses that are cyclic, your weld will cause cracking after some number of cycles. I don't know how long it will take, but it will happen. Guaranteed.
  13. gbent

    Tapped hole position

    There used to be some devices that used a split threaded member that acted like a spring collet, and expanded against the pitch diameter. They had a projection on them to pick up with your probe. I think they were called Tru-Pos. They worked good, but were extremely expensive. As for...
  14. gbent

    Diesel Engine Fuel Dilution

    Check with your oil supplier as to the acceptable dilution. There is no hard rule, as some oils or engines are more forgiving than others. As to the cause of dilution, my experience has been with faulty injectors or fuel lines under the valve covers rather than misfires. Some engines (such as...
  15. gbent

    Waste Heat Recovery

    How valuable the waste heat is depends on what you are trying to do with it. The coolant heat is of little value, it is only at about 180 F. If you have a great need for space heating, it may have a value, but only probably for part of a year. What is your application, or how are you planning...
  16. gbent

    Gasoline vs. Diesel Turbo longevity

    It also has a lot to do with proper turbo cool down. If any turbo engine is ran hard and quickly shut down, the heat soak from the exhaust side will overheat the lubricating oil and turn a small amount of it to coke. Over time, this will block off the oil flow. The turbo life is measured in...
  17. gbent

    Waste Heat Power Recovery?

    Such a combined cycle is available, it just takes a very large stationary installation to work. GE makes a combined cycle power plant they claim 60% efficiency on. They fire a gas turbine with natural gas, and use the waste heat to make steam to run a steam turbine. I don't know the size...
  18. gbent

    NPT Tapping

    To make certain NPT threads are the correct depth, a thread plug gage is needed. Some gages are marked only for "basic" depth, and some have min and max limits also. Without a gage, I would tap the holes until 6 full threads are remaining on the top of the tap. This will produce an...
  19. gbent

    torque capability of slogging spanner ?

    I don't know about tightening torque, but I have removed fasteners that just laughed at an impact wrench rated at 2,000 ft-lb of torque. I use a slugging wrench that is about 9 inches long and a 12lb sledge. The slugging wrench allows the use of a breakover bar also, so the fastener is already...
  20. gbent

    shear loads on countersunk screws

    In this application, is the fastener being used as a screw or a bolt? Given the large, tapered area under the head of a countersunk screw, can the proper tension in the body be reached on a regular basis? My experience is not. The variable friction from forming the countersink in the...
Back
Top