Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Recent content by sbrats

  1. sbrats

    Valve core details..

    CR.. At this point there is no reason why not to use a shrader valve, and I will change and use one for the ease of what I'm doing. It has now become a bit of a 'how can something widely used' not be defined - and being detailed oriented I'd like to see it through. Any other help or suggestions...
  2. sbrats

    Valve core details..

    TMoose.. Yes, the image is correct. The white feature, I believe, sits on the taper cut in the chamber (ref to the image that CR provided)or at the very least maybe 'jams' against the edge created by the taper and the 'smaller' diameter of the bore in the body. The threads that I measured are...
  3. sbrats

    Valve core details..

    Thank you.. Re the TRA book - valid points - leads me to the next couple of lines. CR I briefly looked at the copy of the core configuration dimensions and started to compare these to a presta valve core. I thing (underline think) that everything lines up at first glance. Then I measured a...
  4. sbrats

    Valve core details..

    CR.. Thank you - yes indeed this is the information that I'm looking for. I'll 'cut open' a presta valve stem and compare best I can (sanity check!!) The Tire and Rim Association 'book' is it available to non-members? (even an old one) Stephen
  5. sbrats

    Valve core details..

    Hello, I'm playing in the garage (again) fixing some air equipment related to air fittings on my car and bicycle(s) wheels. I'm looking at using a presta valve core (normally used on cycle tires)in a housing. Is there a specification somewhere for the threads and such (housing and sealing edge...
  6. sbrats

    Small flex shaft design and supplier

    Tmoose.. "Isn't that the definition of low bending stiffness, unless the stiff element is at the neutral axis ?" Yes.. Previously I utilized an small dia aircraft cable at the neutral axis (fixed at both ends)- this allowed the desired rotational and pull. By using a spring (so now I have a...
  7. sbrats

    Small flex shaft design and supplier

    Yes I have, unfortunately in tension the spring will elongate, which is undesirable. Thanks
  8. sbrats

    Small flex shaft design and supplier

    I am looking to see if this is possible and that someone may be of some assistance. I am currently working on a robotic concept that utilizes a hollow flex shaft drive - the flex shaft would be required to transmit a rotational motion (slow motion and only 360 degrees in total) plus a pull load...
  9. sbrats

    Methods for small parts for Medical Instruments

    I'm starting work in a new field as a draftsman. Looking for an overview of how small parts and parts 2mm in size used in a mechanisms (3 to 5mm in size) are manufactured - if Titanium, are most parts EDM machined and what are the limits of detail size? If plastic is everything moulded at this...
  10. sbrats

    datum curve from equation...

    Michael, thank you I created G! first.. then tried to create curve by equation - but the relations fail so I'm out of sequence I think. Can you give me a sequence of events please.. Unfortunately I'm on WF2 so I can not play the trail file. I created the graph file but get lost between the...
  11. sbrats

    datum curve from equation...

    Yes this does give me the ability to vary the pitch - what about an equation to change the pitch within the helix - like a spring with 'flat' ends or in the case of what I'm doing a barrel cam with a 'last' groove which is perpendicular to the central axis (a go home spot that will stop any...
  12. sbrats

    datum curve from equation...

    Any one help with the equation for a variable pitch helical datum curve? thanks
  13. sbrats

    Pro/report - display units?

    I was looking for something different.. If the model is in kg - but the drawing has a format that shows the mass as grams , you would need to constantly change the format - some users will forget etc. So to lower the room for error I wanted to pull the model units and have them as a reported...
  14. sbrats

    Pro/report - display units?

    Is there a way of to query the model or assembly member to display the units of the model. Specifically I have a column in the BOM report that displays the mass of an item (pro_mp_mass) but I wish to display the units (lbs, grams, Kg) Anyway of doing this?
  15. sbrats

    Machining Standards - cleanup cut on base material

    For sake of argument I am buying a piece of 6" aluminum plate against AMS-QQ-A-250/11 - in reality what is the real usable thickness of material that can be 'used' in a design? - or worded in another way - forgetting about flatness etc.. how much cleanup it normally taken per side to accounting...

Part and Inventory Search