Thanks for sharing uncle Robin. But please dont make us wait another year for the next part 🥺

Ok "rough" grinding complete. Next up the fussy stuff. Awesome as always Robin. Cheers, Tom

Thought I was going to bed but I didn’t realize that today is Christmas. Thanks for the gift.

That was cool! Your AutoHarig is such a nice machine, cool to see it in operation. Loved the input about geometry considerations on flat spin grinding, thats a topic completely foreign to me so far.

*spends hours setting up grinding operations, achieves a parallelism most people only dream of* "Yeah, its a bit conical. But that's ok, it'll get lapped anyhow" Your patience and dedication is incredible, truly a role model

I love how deeply you discuss the physics of metrology. Truly stimulating, and not too nebulous for a viewer like me.

Once again Robin shows how the seemingly impossible can be achieved. I’ll probably never need to work to these limits but I always learn something during the vid that I can use. Thank you.

I always enjoy your perspective on how a whole system of forces governs the outcome rather than just the interaction between surface and cutting tool.

37:45 This shot is pure joy. Watching the pattern of the sparks go from continuous cut to four very short bursts at the tippy-tips just like the geometry predicts is very, very satisfying. (You can hear it in lathe work, but seeing it in sparks is so nice. Maybe I'm just easily amused.)

Hey Robin. I know it's been almost a year from your latest video. Hope all is ok. Just want to let you know that your videos inspired me to continue my education into engineering and deeper into tool making. I have gained an almost annoying attention to detail. My boss has given me so much due to this trait. As in more complex work and jobs along with a huge pay increase and title promotion. If it weren't for people like you in the trade young men like me wouldn't have mentors to guide us to the top. Thank you for being sooooo educational and percise. You don't know how much it means to guys like me in the trade to have these structured lessons. Thank you again for all your hard work.

Master Class on fine Toolmaking.

It's a joy to watch someone who truly understands what he is doing ! I think Robin and Peter are so unselfish in sharing their knowledge. Most utube "machinist" are fumbling in the dark and mislead many. Thanks for sharing.

50 years of experience in 1hour.I'v heard things that I will never ever think off.Priceless.Thank you

Always good to hear your insights, 45 minutes well spent.

Robin is one of the few guys I'm sure smiles everyday he walks into his shop to go to work. Awesome stuff. I'm glad I don't have anything that can measure to your levels otherwise everyday will be an existential crisis :-)

Honestly, I don't feel worthy to even watch this fantastic video. However, I do feel blessed. Thank you!!

I look forward to your videos 10x more than I looked forward to Avengers: Endgame. No, more like 100x.

1 year between parts. I appreciate you finding a time to share your experiences, Robin

Tremendous detail and engineering setup, some great tips on metallurgy and brilliantly narrated. Always a pleasure to watch your videos, thanks Robin.

I appreciate your videos and your thoughts more than I could ever express. Thank you.

Found here by Stefans recommendation on his video. Sir, you have excellent YT channel which offer wealth of hard earned knowledge and is enjoyable to watch. Thank You.

Just knowing such precise work can be done is a joy. Fascinating as always. Thanks

Wow. Finally a new treat from mr ROBRENZ. Thanks for sharing

I have watched all your videos, it’s a joy , thank you

Thank you for sharing your knowledge & expertise. I work in a small job shop & anytime an operator complains about me being to "picky" on my metrology, I point them to this channel & let them enjoy the doorway that +/- .005 really is. I love this stuff!

Love to watch this channel and Stefan Gotteswinter. Real professionals. Thanks Robin looking forward to next video.

Outstanding video, part 1 and 2. Thank you very much Robin.

Robin. There aren’t enough words to describe how much I like your channel. Absolutely amazing. I am not a machinist but studied engineering drafting and the mechanics of deformable solids in college, been fascinated with anything that requires mechanical precision ever since. To see you work on design improvements, anticipate process issues and account for all materials deformation is pure pleasure. Keep making those videos, awesome work.

What an absolute joy to watch. This makes me imagine what it might have been like looking over someone’s shoulder in the Moore shop.

Far away is the day we will be able to achieve such precision on our tool and cutter grinder ! But the grinder finish makes for a good illusion of being precise. Best wishes from Switzerland ! I love your videos, packed with informations that I might need, but most likely won't, but that I anyway very much enjoy !

Thanks for sharing Robin. Your work are amazing

Beautiful work Robin, thanks for details, cheers, Doug

I love the work you put into your surface grinder ! Beautiful work as usual Robin. Cant wait to see more!

Unbelievable precision and care you have with your grinding processes. Just blows my little mind. Take Care and Stay Safe. Bob

Thanks for the great tips Robin, your work is outstanding!😊

You are my hero. I am not articulate enough to express how much I enjoy watching you progress through the projects. Thank you.

Another great video! Thanks for taking the time to make this. I just re-listen to the podcast for within tolerance yesterday and was wondering about the next spindel video. So great timing ;-). And again a inspiration to improve my own work.

Thanks Robin always so cool watching your plan and execution

Thanks for putting the work into these. As someone who only tangentially touches on metalwork, I find these super interesting and useful.

Im liking the custom plastic shrouds over the handles

You are very generous with your knowledge. Thank you!

Great video, thanks. Your videos are always packed with experience and insight, and an absolute joy to watch. Look forward to part 3! All the best!

Great work. We shared this video (and part 1) on our homemade tools forum this week.

So amazing how many details there are to this stuff, thanks for posting this

I will never be working to these tolerances but I really enjoy your discussions of what needs to be considered to work at this level of accuracy. Of coarse it starts to influence my work at the tolerances I work at in a very positive way. Thanks for taking the time to video this.

Awesome modified Harig. Really appreciate your precision work 'process' videos, keep up the good work!

Robin, Thank you for the valuable insight. A lot learnt. Cannot wait for the next installment on these spindles. Regards, Reuben

My goodness. What a treat. Thank you.

We have once again been blessed with a video, thanks a million Robin!

Fascinating to think about oil film dynamics and wheel loading and column expansion as sources of systematic errors. Always excellent, thanks for being an inspiration.

Great master class on grinding! Thanks!

Unreal, love the detail you go into awesome work rob

Masterful, Robin. Thanks as always.

A tour de force of top notch education. Thank you so much Robin. I am definitely going to have to watch this video several times.

Fantastic! I have some weird compulsion to watch these videos immediately. Thanks for taking the time to make the video!

I was waiting for this to come out one of these days! The premonition signs made me watch previous episodes yesterday :)

im very excited for the hard turning, that has always fascinated me. it's amazing how we can cut hardened tool steel like that.

Glad for the update. Was wondering if there would be more. Thanks for all the work.

As a Watchmaker I'm used to work within what most People think as 'Insane Precision' (± 0.001 - 0.005mm) But those People don't work with Metal and they rarely work with Machinery. By now I am used to think 'Oh Robin is doing ridiculous Precise stuff again' With my grinding work I never have to consider if my machine is growing in size as it warms up, the Change in size won't even show up on my Instruments. I appreciate the Educational Work you do. I've learned so much even for the 'Precision Range' I work with :)

Robin, you are truly the badass precision king. Keep up the high standard.❤👍

Finally part 2! Though I'm one to talk about long overdue videos...

Glad to see you back brother! I'm thankful that the Lord has kept you to return!

Awesome. You cover so many interesting topics in so much detail, all while giving insight and tips that are unmatched. Thank you for your videos

long awaited video! Thanks Mr. Renz

I had to tell the wife to shut it because Renzetti was on! You could steal the show at IMTS and just setup a booth and sell shirts and take a picture with Robin day. Alway impressed and never disappointed in your content.

Pleasure to watch. Like getting the correct answers to a test.

And now I go to my workshop knowing how far I am from Robin's level. I didn't think about the column growing due to heat...absolutely stunning. I look forward to watch some lapping content in the next video. As always, an awsome job Robin!!!

I did not realize that fact about the modulus of elasticity not changing. Great video as always!

Absolutely fascinating, thanks Robin! I can't wait to see the next installment

What you sat is so true precision is more about understanding and negating the weaknesses of your machines than their basic accuracy, not to say that the job you have done on your grinder is not superb. Another hour of engineering bliss.

Great video, thanks! Looking forward to the next one!

Thank you Robin! Educational as always!

Amazingly detailed explanations, this is the channel for advanced learning :)

Had to wait a week to watch this video in a manner I could concentrate and learn something. Love the automated grinder. Thank you for the effort to make this video Robin.

Thanks for making this video. As always...really great stuff.

Glad you are well. Another class cram packed with information. Thank you master.

So funny I just revisited the first tool room spindle video LAST NIGHT! Thank you robin keep it up we love you and appreciate you !

I learn from your voice over and get entertained and amazed by the video. Thank you.

Just amazing! Your work, your skill and knowledge: just amazing.

Really informative and entertaining video, thank you. Your comments around geometry and ensuring your grind is as good as possible to help you finish the parts are spot on. When I was an apprentice 25yrs ago, one of the best engineers I’ve ever worked with told me “the secret to good finishing, is good roughing”. I have always remembered this and it is so true. Keep up the great work, I find your work fascinating.👌

The long awaited Sequel!! Great stuff Robin. I've watched the first one a half dozen times already, will probably do the same here.

That was so fascinating. My uncle was a tool and die engineer at GM and then opened a grinding service in upstate New York. I remember being in his shop and not understanding anything he was doing. I like to think he was doing work similar to what you're doing. Just fascinating how so many variables come into play to hold those tolerances. And those finishes, holy cow.

Meant to be studying, saw this vid, definitely worth the hour. Always stuff to learn, even though I'm not a machinist.

I was a job shop machinist for 15 years. I had a "Dumor" tool post grinder for my South Bend 17" Turnado. A half thousandth was my idea of precision.... You, my good sir, are in a whole other league.... This is fascinating. Thanks for explaining everything so thoroughly.

I think everyone would enjoy a monthly video from you.

Really good material here - thanks, Robin!

You're an inspiration Robin, thanks for sharing. 🍻

Awesome video! Thanks for the knowledge 🙂

Extremely interesting. Thank you.

Great video Robin, really appreciate all the over the shoulder talk at the grinder. Lots more to think about and consider now since every bit of info for toolroom grinding is coveted. The grinder looks awesome too, that silplat looks like the ticket. Cant wait to see what's in store for the other two machines! Cheers Alex

Hey Robin, I’m a 25 year old self taught mechanic turned machinist. I’ve turned into the go to guy at the company I work for to do most off the tooling/tight tolerance work that we do. I just want to thank you because your channel opened my eyes to elasticity and it has changed my out look on everything. Thanks you for sharing and I can’t wait for the next video

Thanks for all your hard work making these fantastic videos, Robin! I enjoy them so much, and have learned an incredible amount from them. As opposed to many other YT machinists, you keep everything relevant, without too many eh's and uhm's, and you never fail to amaze me in the way you consider all perameters and details. Also very impressed with the creativity with which you set up a project. Love it! I've almost finished watching all your videos, so I'm wondering when you will upload more? If needed, I will watch them all again.

Excellent content

Really cant wait to see the next part of this series! :-)

Thanks for the video.

I doubt I will ever have the chance to use any of this, but I really appreciate the detail you put into this art, and you help me understand better the Intricacies of Interactions in systems, which really applies to everything from physics to medicines and herbs, to emotional healing, and you describe it in an easy to understand manner.

Just insane! Awesome work man!

Haven't got a clue what you are talking about but I'm addicted

Woo Hoo- New video!!!

Hey mister, we appreciate your videos very much.