I wonder if you realize that for every kid you taught in school, there are probably about 1,000 youtubers learning from you today. Thanks from all of us.
Back in the 1960s a friend produced movies for the Veterans Administration. In a film about blind veterans, he had a sequence of a blind quality control inspector who determined roughness with his fingertips using a plate.
Long ago I tried an experiment of testing surface roughness using my fingernail and realized it was the sharpness of my nail that was the biggest limiting factor of how sensitive that method was. I had a fairly long thumbnail at the time so I stuck a sharp needle through it and used the tip on the needle as my probe. Let me tell you the difference was astounding! If you don't have any long nails and want to try this you can just as well epoxy (or other very hard glue) glue a sharp needle to your nail for a quick investigation of the physical dynamics of the system. If you are at all into surface texture, I bet you will enjoy it. HA! I should have listened to the whole video before commenting. Good one. :-)
Profilometers are often used to measure the roughness, the avg(Ra) the peaks(Rp) and the valleys(Rv), of the decks of an engine block and it's associated cylinder heads after they've been resurfaced. Some cylinder head gasket manufacturers require a certain finish in order to maintain a seal with their gasket.
This is fascinating - I really appreciate your making these videos. I am aware of the Cat engine surface finish requirements for the crankshaft etc. but as a commissioning engineer I don't have to measure or directly deal with that. That is way above my pay grade LOL!
Mr. Pete, as usual, always interesting never boring and always educational. Are you taining an apprentice? The end of 'Mr. Pete' videos would have a very significant impact on the RU-vid community out here!!! Many thanks for sharing young man. Regards. Joe.
Interesting video Lyle, but then yours usually are. I'm commenting because my job as an external and internal grinder involved using these. We made turbochargers and the bearing surfaces on some of our products had to be either 8 or 12. So I have used that very same machine 100s if not 1000s of times. Remember I had to stop work early aged 43 when my lower back wore out, but I did that job for 16 years. However you may have seen over the last year I still manage to maintain the skills of an engineer e.g. making the model steam engine, plus other projects that I do.
This was a great video with roughness or smoothness "Surface Roughness Scales" as a shop-floor tool. Thanks for the help! T J (Tom) Vanderloop, Author, Technology-Instructor & Consultant to Manufacturing; ATEA, AWS & SME
Thanks for the video, and basically everything ! As a home gamer, and a neophyte one at that, I often wonder what the surface finish can tell me about my cutting speeds/feeds, or bit sharpness, perhaps even the quality of the metal. Its pretty hard when starting out, and you don't have a seasoned vet over your shoulder to interpret the results.
Better way to compare surface finish using the GE style samples, is by scratching both surface with your fingernail. The difference is quite obvious, and in my personal experience, is more accurate than visual.
This is a very interesting subject for sure! Can't wait for part 2. Not sure about milling, but for turning you can calculate the surface roughness. If you know the target roughness in Ra, insert radius and/or the feed. You need know atlest 2 then you can calculate the 3rd. This calculation is in metric values. So if the blueprint would call for surface finish of say 1,6Ra and you would use an insert with a 0,8 noseradius then the math would look something like this: Feed pr rev = Square root(0,016*32*0,8) = 0,202 Ra is in microns so that needs to be coverted to mm, so 0,016. The 32 is a constant. 0,8 is the noseradius. There is more factors that influence surface finish obviously but this should put you quite close to you target.
Organic manufactured products consist of atomic scale additive processes. Of course it's going to look better than anything produced by macroscale subtractive methods. Once nanoscale tools are as common and affordable as lathes and milling machines then what we manufacture will rival and exceed that of nature. I hope that day comes in my lifetime.
@mrpete222 Did you think to try your endoscope to look at the vinyl record? It should have a much shorter focal point and should afford you a more close-up picture. Probably at a lesser resolution than your normal camera however.
Wonder how they made those GE roughness gauges, they don't appear to have the individual tiles soldered together but I wouldn't think it could be cast with that much detail.
It matters to ultrasonic inspection i need my company to better there machining..i need to show them what i need for better results because i am the inspector that effects the surface of inspection i need the machine inserts to cut very fine no record grooving this make a wave that increases the amplitude of my ultrasonic response that is un acceptable to my inspection ...
A question for whoever can answer. I have a pair of the GE Roughness Scales and I'm curious as to what they are made out of. Because there is green spots pitting the metal like it's tarnishing. And it's magnetic and they have a good bit of weight to them. It isn't that bad I'm just curious. I do use them. But they were like this when I got em. And if anyone has an idea on how to stop the tarnishing plz let me know thx. I used some silver polish on em and it worked pretty good they are nice and shiny. Just one has green little spots on it the other just has a few.
If you are interested in inspecting specific surface defects you can buy surface defect blocks. Very interesting tool www.carbideprobes.com/surface-defect-evaluation/ I deal with alot surface roughness inspections and just found out about this tool.
