Heatshields; single use or multi use? Here is the power to choose! - page 2 - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

• #15 by belchfire on 20 Feb, 2012 22:30
• How do you determine depth? I tried this awhile ago but didn't want to chance it as I had new ones. When I attempted it, I used a 3/8" bearing ball and used a flat washer as a depth gauge. Crushing the whole thing in a vise until the ball hit both sides gave me consistent depth. I polished the new raised area slightly to remove any burrs. It looked good but I chickened out. Work hardening and metal fatigue aren't an issue?
  Looks like you've had success. I've had new ones crap out so might as well give this a chance.
• #16 by Mark(The Miser)UK on 21 Feb, 2012 01:58
• Quote from: belchfire on 20 Feb, 2012 22:30

  How do you determine depth? I tried this awhile ago but didn't want to chance it as I had new ones. When I attempted it, I used a 3/8" bearing ball and used a flat washer as a depth gauge. Crushing the whole thing in a vise until the ball hit both sides gave me consistent depth. I polished the new raised area slightly to remove any burrs. It looked good but I chickened out. Work hardening and metal fatigue aren't an issue?
  Looks like you've had success. I've had new ones crap out so might as well give this a chance.
  

  I hadn't found work hardening to happen   EDIT  oh  yes it does , or if it does, to be insignificant. The face of the nozzle is way up on the hardness scale, and it is this that 'smears' the shield to a near 'wring fit' over a period of reuse.
  
  Fatigue is where it clearly goes. When the fatigue gets it, will depend on how much 'un-distortion' you give it each time. 
  It would appear that I hadn't been overdoing it, as I've only broken one shield in some 60 reworkings.
  
  I probably undistorted less as time went on, partly apprehension, partly getting it 'right', and partly where I thought the shield's upper seal edge more readily sealed with it's personalised polished surface, due to my policy of the same shield, same hole, and same injector body, and same nozzle where possible.
  
  One improvement I suppose would be to anneal the shields each time. It would help longevity, but then again, as tey last , for my particular set, at least, for some 14 reuses do Iwant to perlong them further?. Well even with my thrifty nature, probably not. Even if production stops, there is always 2nd user ones from dismantlers, available when rescuing old French made OEM injectors/nozzles
• #17 by belchfire on 21 Feb, 2012 16:49
• I understand cheap. I also understand frugal and that's a much more desired term. Maybe after 14 times a person just being cheap. I don't for see any shortage of seals and in the unlikely event that happens, there are alternatives (see my other post about mercedes seals). By the time there are no more seals, we'll probably be putting a handful of garbage in the flux capacitor and accelerating to 88 mph. 
• #18 by theman53 on 25 Feb, 2012 12:06
• split topic...
  
  Back to heatshields