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Recent content by coughdrop

  1. coughdrop

    Taptite screws

    MSU2000, Sorry I didn't answer your question about what I mean by "snatch". Screwman mentions checking the clutch on the drive gun, if this gets worn it can momentarily overload (ie higher than set torque)which we call "snatch". I have come across 2 isolated incidences in the past of "cheap...
  2. coughdrop

    Taptite screws

    MSU2000, OK, so the material is perfectly suitable for Taptites (AlSi10Cu2Fe) in fact it is very close to many of the castings we produce and fit Taptite screws to. So, you are drilling the hole only 0.075" longer than the screw length. Is this the depth of the full dia' or to the drill...
  3. coughdrop

    Taptite screws

    Sorry guys! I said I was rusty on Imperial measures! MechEng13 is of course quite correct. I have encountered sheared off heads with Taptites in the past, after all of the hole dia/depth checks were verified, it turned out to be the "snatch" effect of the clutch on the electric torque driver...
  4. coughdrop

    Taptite screws

    MSU2000, something feels wrong about this. I like screwman have also worked for too long with Taptites. I am assuming that we are talking about Tri-lobal thread forming screws here? I'm a little rusty on my imperial units but, 11 in-lb seems excessive! I convert this to 132lb/ft? 97N/m? A...
  5. coughdrop

    Power steering feedback

    I agree with the engineering mod's/comments which Greg & Pat are suggesting but, I can't help feeling (excuse the pun!) that there is something currently wrong with the vehicle. Scoobies and the like should drive rigidly in a straight line, the self centering action of the PAS is also quite...
  6. coughdrop

    Power steering feedback

    I think that you may actually have a Tire / Geometry set-up problem here. I run a 1984 Audi Ur quattro (turbo) which was the first of the road going 4 wheel drive "supercars" and is very similar to a modern Scooby. The car should have a real bias to driving in a straight line even with your...
  7. coughdrop

    Aluminium problems with heat transfer/bending

    Andy, I work with Aluminium alloy castings rather than primary Al sheet etc., however the principles are the same. The 60mm sides are not heated, so the heated 100mm base is trying to expand more than the 60mm sides - hence the bowing. There is a Coefficient of Thermal Expansion figure...
  8. coughdrop

    Magnesium transmission casings

    Magnesium high purity alloys such as AZ91 derivatives are very suitable for trans' cases which are made using the High Pressure Diecasting process. VW as quoted above have extensive experience. Corrosion is less of an issue with the modern alloys but, care must be taken with insertion of other...
  9. coughdrop

    Needed, Large Cross Flow Fans

    Try www.eltafans.com or www.woods-fans.com they are both indutrial air movement manufacturers handling series production or bespoke one-off solutions. Regards, John.
  10. coughdrop

    ducted fan use for air intakes on carbed engines

    Andybee, There were some "Frogeye" sprites fitted with superchargers. I helped to convert a standard sprite as a "works team replica" some 20 years ago. The carb jets were bigger and we used WD40 in the dashpot to shorten carb "piston lift" response. I suggest you...
  11. coughdrop

    Coremaking

    Hi Taila, Ok, this is going to be a bit drawn-out I can tell ! Your colleagues have informed you that:- "the core does not take the load of metal above it as pressure is constant about a point in all directions." I'm sorry to say that this is not necessarily correct. I also work in an...
  12. coughdrop

    Coremaking

    Hi taila, I think this is the wrong forum for this question but, trying to help with the question. The compression strength of cold box cores has little relevance to it's functional bend strength. It's difficult to help specifically without more information, for example, what material are you...
  13. coughdrop

    Heat equation

    celticmad, I think the best solution is to contact a burner manufacturer, for example NA-Stordy or Nu-Way. I have found both to be very helpful with application advice in years gone by. www.stordy.co.uk (part of North American Manufacturing Co.) Cheers, John.
  14. coughdrop

    Nobody offers me a job, even an interview...!

    Zimbali, THE method of getting into automotive jobs in the UK is by using recruitment agencies for example www.jonlee.co.uk as most Auto' Companies have limited HR personnel. The current situation is of ongoing cut-backs in the UK with more jobs being contracted-out to temporary contractors...
  15. coughdrop

    stripped out Al. bolt holes

    tbuelna is of course correct in his comments, however given the nature of cylinder head castings and the lack of space, it seems prudent to compromise with the Helcicoils. A standard practice is to use "thread-lock" adhesive when inserting the coil, This will allow further occasions of...

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