Brief description of how an autocollimator is used to measure straightness and flatness. Followed by my mirror system design and construction details.
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Runtime: 41:53


Railgap Esoterica
Railgap Esoterica - 3 dager siden
Three days, huh? Including drawings and planning? Including finishing? Do you sleep? I admit to some skepticism. I think many experienced tool makers would need three days just to make the knobs and small bits of custom hardware you used.
ROBRENZ - 2 dager siden
Design/drawing time not included in the "about 3 days"
MuellerNick - 5 dager siden
Now ... dammit! Such a nice and clever construction with excellent details. Plus machining that is worth every precision instrument. And all these cool looking parts frosted with the nice finish!
I pull my hat!
Bali 025.0
Bali 025.0 - 6 dager siden
Diogo Dallago
Diogo Dallago - 8 dager siden
Amazing work! 👏👏👏👌👌👌
ROBRENZ - 8 dager siden
Thank you very much!
Valanjo - 10 dager siden
Parabéns pelo trabalho.
Qual é o tipo de acabamento superficial?
ROBRENZ - 10 dager siden
jateado com contas de vidro finas
Susan Kimbal
Susan Kimbal - 16 dager siden
Great video, such fine detail on your work. I am curious... why didn't you use three adjuster screws on your mirror instead of four? Kinda feeling like four screws might warp the glass. Or did I miss something here. :)
ROBRENZ - 16 dager siden
Thanks, there are only three support points, one is fixed and the other two are the differential screw adjusts for tilting in two different planes with minimal cross talk.
cwtoyota - 17 dager siden
Excellent, as always. Great design on the turning mirror.
I have that same Davidson autocollimator and I'm likely to copy some or all of your design features.
Eric Beyer
Eric Beyer - 18 dager siden
Wow Robin, great work as always! I love to see the thought you put into your projects.
ROBRENZ - 18 dager siden
Thank you! 😊
Bruce Argyle
Bruce Argyle - 19 dager siden
Nothing can be said except OMG, Legend.
shad wilson
shad wilson - 20 dager siden
@ROBRENZ I'm interested in what else you did to the CR Steel straight edges beyond peening the one side to pull/push the bow out. Did you grind or lap them? Thanks for the vids, a wealth of info I can't follow the first time I watch, usually have to back up several times.
ROBRENZ - 20 dager siden
Just straighten, they dont have to be perfect, they only guide the mirror sled enough to keep the cross hair in view.
LeoMakes - 21 dag siden
This is so thoroughly impressive! I especially liked the machining of the flags and the glass bead finishing. Super interesting project!
Bruce Washington
Bruce Washington - 21 dag siden
As soon as I stop weeping, I am going to sell all of my tools! What an amazing job Rob. Thanks so much for sharing!
Jimmy P
Jimmy P - 22 dager siden
I made a center punch today ,tomorrow a ball peen hammer
N. M.
N. M. - 23 dager siden
For whatever reason, this reminds me of my days as a fusion splicer. Cool stuff.
Dong Chen
Dong Chen - 24 dager siden
What an amazing design! I have an autocollimator, and I always find it inconvenient to use because it is too long. the turning mirror solve this issue! Thank you Robin. BTW, how do you like the kollmorgen? I had the same model before but switch to Higer & Watts because mine kollmorgen's image seems to be a little dim.
Dong Chen
Dong Chen - 24 dager siden
@ROBRENZ Good for you! I love the optic-amplified adjustment on the kollmorgen. Mine kollmorgen may not be storaged properly by the previous owner, glasses develop some cloudy mark on the surface.
ROBRENZ - 24 dager siden
My Kollmorgen is very bright, I have to turn it down.
Bhima Pandava
Bhima Pandava - 25 dager siden
Wow, this is fantastic!
Bob Vines
Bob Vines - 25 dager siden
Robin, this is a very interesting video. I _finally_ realized how you slotted the three differential clamps with your Bridgeport. :P I'm afraid that I was being "dense" as I watched -- I had to think about it _way_ too long in order to understand what you were explaining about how you actually went about the slotting. I feel "silly" for not immediately understanding your explanation -- I misunderstood what you meant by a "blind slot" and mistook it for a slot that didn't go _through_ the part, until my dim bulb finally came on as I _finally_ realized that the clamps wouldn't work too well without the flexures given by the slots.

I really shouldn't watch videos that require _any_ thought after an entire day of migraines.... :(

I'm looking forward to watching your _next_ video without a migraine or bad headache! All of your videos should be "required reading" for Mechanical Engineers because of your well thought approach to your design and machining of whatever you are working on.
ROBRENZ - 25 dager siden
Thanks for the kind words.
Mihai Dumitrescu
Mihai Dumitrescu - 25 dager siden
Lovely work ! One question: would that be stable enough without stress relieving the welding ?
bo - 26 dager siden
always love your videos, this one was awesome as per your usual. i thought "he's pushing that sled with a skewer to avoid inputting heat" and then you said you were doing it for that very reason. i learned that from you. thanks for teaching and it never ceases to amaze me how much i learn every time i watch. you've multiplied your talents over a lifetime. respect on multiple levels!
ROBRENZ - 26 dager siden
Thanks again!
wotnoturbo - 26 dager siden
Looks flat to me, give me a call next time you need to check one, excellent work Robin
Mark Pierman
Mark Pierman - 26 dager siden
Fantastic and impressive as always Robin!
ROBRENZ - 26 dager siden
Many thanks!
Thomas Lizon
Thomas Lizon - 26 dager siden
Amazing work as always. Such a level of precision. Impressive and inspiring. Thank you very much.
ROBRENZ - 26 dager siden
Thank you very much!
Ryan - 27 dager siden
An absolute privilege that you take the time time to share your technique and talent. So many lessons in a short video, thank you Robin, you are an inspiration.
ROBRENZ - 27 dager siden
Glad it was helpful!
Bob Miller
Bob Miller - 27 dager siden
Great video and job Robin. Always a treat looking over your shoulder and learning. Thankyou!
саша пашп
саша пашп - 27 dager siden
Please show how in real work with this device can be chacked surface plate
Saki630 - 27 dager siden
Beautiful video.
I am allergic to metal and milling but I still paused my pr0n to dedicate an hour to this amazingly informative video.
Keep up the high quality content. There are many people who learn from your channel.
cruch9 - 27 dager siden
Any good videos on turcite? Want to learn more about it. How did you fasten to body?
Luciano Vasco
Luciano Vasco - 27 dager siden
Excelente, adorei, venho procurando por isso a muito tempo. Agora estou ansioso pra ver você fazer o resto, a luneta . Espero que não demore, kkk, porque estou mesmo querendo muito ver. Obrigado Luciano.
ROBRENZ - 27 dager siden
Muito obrigado.
саша пашп
саша пашп - 27 dager siden
Ih my god is sooo goood
West Weld
West Weld - 27 dager siden
If I learn 1/2 the things you show on your videos I'll feel accomplished as a machinist........I'm not there yet.......not even close
Glenn Stasse
Glenn Stasse - 27 dager siden
Although I’m not surprised at Robin’s skill, meticulous craftsmanship, or design capability, having seen other of his videos, I am amazed at all the effort that went into building these things to measure up just his own plate! And how does he know about all these special parts like the bearing washers and the funny screws and the pads the mirror gizmo spins on? If there was a Nobel prize for machining Robin would be a lock! Spectacular! (And thanks for showing all this.)
Uncle Bob's Bees
Uncle Bob's Bees - 28 dager siden
The thought process involved for your order of operations always tickle my brain. The level of experience displayed is just awe inspiring.
Greg Done Technical
Greg Done Technical - 28 dager siden
As usual, you have presented a beautiful precision assembly and I have learned many things. The component used to lock the differential screw is wonderful and I shall be using that idea on a current project of mine. Thank you for freely sharing you knowledge.
Solid Rock Machine Shop Inc.
Solid Rock Machine Shop Inc. - 28 dager siden
Another great video Robin! Keep them coming.
ROBRENZ - 27 dager siden
Thanks Steve! ATB, Robin
slausonm - 28 dager siden
Robin, you are on a much higher plane of machining than I but you talk about basic things in your videos that I try to teach my high school engineering and tech students. Thinking about planning and order of operations is very important. Thank you for posting this video, I enjoyed every bit of it.
ROBRENZ - 27 dager siden
Great to hear!
bcbloc02 - 28 dager siden
I watch this and all the precision fits and pieces while I am beating together pieces with a sledge hammer in my shop. I feel like I barely rate caveman status. lol When I first saw those parts I thought they were castings. Not sure what is more impressive the level of fit detail or that you could make all that in 3 days. Just WOW, Impressive!
ROBRENZ - 28 dager siden
Thanks Brian for the very kind words. ATB, Robin
Stu McCabe
Stu McCabe - 28 dager siden
Absolutely beautiful workmanship and design (mechanical and aesthetic). Thanks for the video.
ROBRENZ - 28 dager siden
Thank you very much!
Scott Muller
Scott Muller - 28 dager siden
Great work ! If i could ask where are the mirrors from ?
ROBRENZ - 28 dager siden
A friend gave me a bunch of them.
Dudley Toolwright
Dudley Toolwright - 28 dager siden
Amazing work. My initial thoughts were that you had just modified a commercial product. As always a ton of useful tips and tricks.
ROBRENZ - 28 dager siden
Glad it was helpful!
William Garrett
William Garrett - 28 dager siden
You are a genius! A genius is a person who displays exceptional intellectual ability, creative productivity, universality in genres or originality, typically to a degree that is associated with the achievement of new advances in a domain of knowledge.
ROBRENZ - 28 dager siden
Thanks for the kind words.
RadarDoug - 28 dager siden
I'm always amazed to see laboratory grade equipment built in your home shop. I guess that just shows that while the tools are important, it's really the craftsman that counts.
you could use it
you could use it - 29 dager siden
Your ships driveshaft is outta wack $1M dollers , your airframe is bent $1M dollers, Gravity traveles in waves, priceless
Adam Norton
Adam Norton - 29 dager siden
Sascha Oswald
Sascha Oswald - 29 dager siden
Nothing my small intellect could come up with would add anything useful to this. Simply spectacular. Thank you so much for sharing your knowledge...we are not worthy!!!!
I think you should have made a few of these while you were at it, I bet you'd have some eager customers...
ROBRENZ - 29 dager siden
Glad you enjoyed it!
braxtonec - 29 dager siden
Didn't know what one was, but thanks for the thorough and detailed explanation. I have a greater appreciation for the finer points of their use and even more so for the construction of the 'accessories'. Outrageously refined and clean design. This is my second time watching and it just keeps getting better!
ROBRENZ - 29 dager siden
Thanks for watching!
Chuck Norris
Chuck Norris - 29 dager siden
Those mirror stands are totally awesome.
ROBRENZ - 29 dager siden
Glad you like them!
Pant1KR - 29 dager siden
Wow this is both inspiring and humbling to watch. The silver solder part was satisfying!
ROBRENZ - 29 dager siden
Glad you enjoyed it!
Gas Worker
Gas Worker - 29 dager siden
Brilliant! Thanks for sharing!
shane - 29 dager siden
over the years i have been watching Rob work, Ive wondered if the absolute precision caries over to the rest of his life's adventures? I guess OCD can be a good thing at work as long as you can turn it off at home. My Dad always told me "if you are not going to do it right, then don't do it at all." He also said spend your money once, and buy the top of the line best available, and you will always be satisfied with it"
Andrey Novoselov
Andrey Novoselov - 29 dager siden
I'm just finishing reading Foundations of Mechanical Accuracy. But it's one thing reading about precision and accuracy and whole other thing to see and witness it. Thank you Robin for this inspiring video!
PS I wish you'd show the details of lapping the carbide pads square (I'm guessing they are square).
Beach&BoardFan - 29 dager siden
Would you do a time lapse video of you testing a surface plate with this?
ROBRENZ - 29 dager siden
You will see that.
Beach&BoardFan - 29 dager siden
What is turpite?
ROBRENZ - 22 dager siden
@Beach&BoardFan That would not be a good application for Turcite
Beach&BoardFan - 22 dager siden
@ROBRENZ If you're doing work that requires a height gauge to slide across your surface plate a lot, would it be beneficial to use a turcite pad to protect the faces of the surface plate and height gauge? Or would that just diminish the accuracy of the gauge?
ROBRENZ - 29 dager siden
Joel L
Joel L - Måned siden
Stunning work. I sure wish I was 1/10th as clever and thoughtful. Thanks Robin for sharing. I learn more than I ever imagined watching you, the humble master, at work. 👍😎👍. Joel......
ROBRENZ - 29 dager siden
Glad it was helpful!
Nicholas Stahl
Nicholas Stahl - Måned siden
I picked up a Hilger & Watts autocollimator on eBay to measure my own surface plate only to discover how difficult it is to find proper target mirrors. So, I started designing my own. Needless to say, I'm feeling a little less confident in my own design now.
This is a really well thought out and executed design. Well done!
Also, I guess need a bead blaster now. Such pretty finishes on those parts...
ROBRENZ - 29 dager siden
It can be as simple as the one I showed first.
Job Kneppers
Job Kneppers - Måned siden
Wonderful job Rob, really clever and also an appealing design. I'll take my hat of for you sir! Thank you for sharing this great content. Best regards, Job (PS; is there a digital camera in the autocollimator for recording the values on each location? Just wondering)
ROBRENZ - 29 dager siden
No but I use a digital microscope to view through the eyepiece.
Timothy H.
Timothy H. - Måned siden
Robin, what media and psi do you use for your finish?
ROBRENZ - Måned siden
Medium size glass beads at 50 psi
Bosted Tap
Bosted Tap - Måned siden
Excellent demonstration Rob, brilliant design and manufacture of the instruments. I've used a 0.025 mm per Metre level on tables and machines, and plotted the flatness deviation using a spreadsheet (took me several days to get the formula)
Great vlog, thanks for sharing and best regards John.
Mark Makes
Mark Makes - Måned siden
I spent some time trying to think of something appropriately insightful to say, or perhaps a message that adequately conveys an appreciation of your skill and intelligence. Neither are attainable so I'll just throw out a comment to feed the algorithms...
outsidescrewball - Måned siden
THANK YOU for your time to create and share..SO many lessons
ROBRENZ - Måned siden
Thanks Chuck! ATB, Robin
D6c10K - Måned siden
Excellent work as always......I'm curious why you decided to use just two feet on the bottom of the mirror rather than three like are on the sides. Is that so you're contacting the surface plate in a narrow line?
ROBRENZ - Måned siden
Only two feet are the measuring system the third foot is just for lateral stability on the large mirrors