[RBW] Re: Zyglo analysis useful?
Dye penetrant inspection will reveal discontinuities which are open to the surface. You spray with a purple dye then use a special cleaner to remove it. Ths is followed by a white developer. Any cracks will show up as thin purple lines against the white. Spray cans are available online at testing materials supply houses. Engine heads are often tested with a wet dip method and UV lighting. YOu can consult an automotive repairer for leads there. Older cranks, made of steel, can also be tested using magnetic particle inspection. Here, an electro-magnetic yoke is placed on the material and powered and colored iron filings are sprayed out between the poles of the yoke. If there is a discontinuty, the sides of if become magnetic poles and the iron particles adhere and reveal it. This method can reveal flaws which are slightly sub surface (1/8) and not open to teh surface, as well as those which open to the surface. It does not work on Aluminum. You can have the parts X-rayed. Industrial testing agencies can do this for you. They usually charge by the picture. Xrays of your old crank will probably cost as much as buying a new crank, but for notable cranks which are historically important, it is a possible way to go. Have fun! From: mitchelr mitch...@onid.orst.edu To: RBW Owners Bunch rbw-owners-bunch@googlegroups.com Has anyone every used the Zyglo dye analysis process for parts such as a crank and if so was it worthwhile? --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups RBW Owners Bunch group. To post to this group, send email to rbw-owners-bunch@googlegroups.com To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en -~--~~~~--~~--~--~---
[RBW] Re: Zyglo analysis useful?
I'm no metallurgist, but I would think that a thorough cleaning and a once/twice/thrice over with the hairy eyeball would be enough to detect any cracks on a crank, given how little real estate there is to cover. Focus especially on areas that might be possible stress risers- crank/spider interface, taper, pedal eye, and any machining on the arm. On May 13, 4:17 am, mitchelr mitch...@onid.orst.edu wrote: Hope this is not too far off topic. I have an old Sugino Impel crankset I want to bring back into use specifically because of its 94/58 five arm configuration (and the daunting cost of alternatives such as the TA Carmina). Ebay supplied an old Sugino set. But is it any good? My LBS folks looked it over and offered assurances but I'm still uncertain. Has anyone every used the Zyglo dye analysis process for parts such as a crank and if so was it worthwhile? I'm presuming automotive engine rebuilders will have the dyes and UV lighting but are there other sources? Many thanks for the good advice on this odd project. Rich Mitchell, Corvallis Oregon --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups RBW Owners Bunch group. To post to this group, send email to rbw-owners-bunch@googlegroups.com To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en -~--~~~~--~~--~--~---
[RBW] Re: Zyglo analysis useful?
In my days as an aeronautical quality engineer, I used a dye check method for finding cracks in metal. A red dye was painted on, then cleaned off. Then a white powdery developer was sprayed on. It pulled the red dye out of any cracks (even minute ones not visible to the eye) and made them very evident. This took no special lighting. I'm betting that the dye and developer is available fairly cheaply. Rob On May 13, 2009, at 9:43 AM, Jeremy Till wrote: I'm no metallurgist, but I would think that a thorough cleaning and a once/twice/thrice over with the hairy eyeball would be enough to detect any cracks on a crank, given how little real estate there is to cover. Focus especially on areas that might be possible stress risers- crank/spider interface, taper, pedal eye, and any machining on the arm. On May 13, 4:17 am, mitchelr mitch...@onid.orst.edu wrote: Hope this is not too far off topic. I have an old Sugino Impel crankset I want to bring back into use specifically because of its 94/58 five arm configuration (and the daunting cost of alternatives such as the TA Carmina). Ebay supplied an old Sugino set. But is it any good? My LBS folks looked it over and offered assurances but I'm still uncertain. Has anyone every used the Zyglo dye analysis process for parts such as a crank and if so was it worthwhile? I'm presuming automotive engine rebuilders will have the dyes and UV lighting but are there other sources? Many thanks for the good advice on this odd project. Rich Mitchell, Corvallis Oregon --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups RBW Owners Bunch group. To post to this group, send email to rbw-owners-bunch@googlegroups.com To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en -~--~~~~--~~--~--~---
[RBW] Re: Zyglo analysis useful?
Just ride and smile, my friend. On May 13, 6:17 am, mitchelr mitch...@onid.orst.edu wrote: Hope this is not too far off topic. I have an old Sugino Impel crankset I want to bring back into use specifically because of its 94/58 five arm configuration (and the daunting cost of alternatives such as the TA Carmina). Ebay supplied an old Sugino set. But is it any good? My LBS folks looked it over and offered assurances but I'm still uncertain. Has anyone every used the Zyglo dye analysis process for parts such as a crank and if so was it worthwhile? I'm presuming automotive engine rebuilders will have the dyes and UV lighting but are there other sources? Many thanks for the good advice on this odd project. Rich Mitchell, Corvallis Oregon --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups RBW Owners Bunch group. To post to this group, send email to rbw-owners-bunch@googlegroups.com To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en -~--~~~~--~~--~--~---
[RBW] Re: Zyglo analysis useful?
We use the Magnaflux Spotcheck dye penetrant system at work. It's easy to use, and will highlight cracks the reach the surface. No UV needed. A set of the three spray cans needed will run you under $40 (plus shippping) from Grainger or McMaster-Carr. Bill On May 13, 4:17 am, mitchelr mitch...@onid.orst.edu wrote: Hope this is not too far off topic. I have an old Sugino Impel crankset I want to bring back into use specifically because of its 94/58 five arm configuration (and the daunting cost of alternatives such as the TA Carmina). Ebay supplied an old Sugino set. But is it any good? My LBS folks looked it over and offered assurances but I'm still uncertain. Has anyone every used the Zyglo dye analysis process for parts such as a crank and if so was it worthwhile? I'm presuming automotive engine rebuilders will have the dyes and UV lighting but are there other sources? Many thanks for the good advice on this odd project. Rich Mitchell, Corvallis Oregon --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups RBW Owners Bunch group. To post to this group, send email to rbw-owners-bunch@googlegroups.com To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en -~--~~~~--~~--~--~---
