MAKING A BETTER ADJUSTABLE TIR LATHE CHUCK 

Robin, such a clean design - Love the super close fit fine pitch screws. Thank you so much for taking the time to film and share this design.

A new Robrenz vid. The holy grail of RU-vid machining.

Babe, wake up, Robrenz uploaded a new video.

I especially like the re-purposing of the socket head cap screw! When you started talking about the elongation of non-homogeneous constituents and the grain structure of the material in the direction of working during forging I really got excited. Bravo! All the best, Tom

Had to push out watching this video until I had enough time to watch in one shot without distractions. lovely work as always Rob

Wow! Dan Gelbart. That's a name I haven't heard in a while. I worked at Creo when it had 150 people. Dan let me have access to his library of precision design texts. Learned buckets from them. Enjoy your posts!

If only we could clone Robin and fill a university program with him instructing. I wish even half my instructors were as skilled, knowledgeable and capable of communicating this effectively. Always fantastic useful content.

Spent the first 12 years of my career as a toolmaker, specifically mold making. Spent the last 27 years applying the skills and techniques learned and that you are documenting of precise toolmaking techniques. It’s amazing to me the tools we make do with - fixtures and machinery, that were never thought out to the level of precision that toolmakers demand. Keep up the good work, and the awesome documentation of our trade!

The quality of parts/work that gets cranked out on this channel is top fkn class!! Gives us a real insight into how engineering actually practically playes out when high tolerances are required! Even tho i have done some highly accurate work myself ik constantly suprised and learning new things with ROBRENZ!! LOVE IT!!

Hoping you and yours are well this season, God's blessings on you all!

Once again I feel like a half-wit freshman who wandered into a grad class, but even I can learn a few things for today and a lot of things to look forward to trying in the future. Thank you very much for all the time and wisdom you've put into this.

That shot with the giant orange c-clamp and the indicator coming through the bore was the most mad scientist thing I’ve seen on this channel hahaha As usual, thanks so much!

Not a criticism at all, but sometimes I watch your videos to fall asleep to 😅 I figure maybe I'll learn something even if I fall asleep mid video lol, subconsciously. Love the chuck idea!

Robin. Thanks for your patient kind and considerate manner. You're an educator and a great mind. Cheers Ken

Would it be better? if we cut a little step on the out side edge of the adjust screw then engrave the division marks on another ring and gentle press fit it to the screw. Just fit enough so it not turning around but we still able to adjust it. Because the thread with move a little bit over time so those marks wont always stay on the same spot as we want. Just my thought, not trying to be smart 😅. I got no more word to say about your works but still have to comment.😅

Ditto what everyone else said! You are a treasure and a blessing!

Robin, I design custom chucks and tooling and I must say, your videos are always insightful and I love watching them to learn new tips and tricks for improving my designs. Thanks!

Today was looking to be a soul-less day, full of software design and problem solving for me. Thank you so much for lighting up my day with your precision design, manufacturing and assembly of cool things!!! :D

I'm grateful every time you post! Your video on spindle bearings guided me to design and construct my own spindle for my Quorn tool grinder protect using DB ground bearings. Thank you! I know I'm not alone in appreciation of you sharing knowledge.

Hello Robin, my comment is not specific to this video. I just wanted to thank you for sharing your knowledge and especially your thought process during your projects. When I first found your channel (Stefan Gotteswinter recommended you) I basically did not understand anything you explained or did ... it just was way to advanced for me. Well the virus caught me and I bought a lathe, mill, surface grinder, d-bit grinder, and lots and lots of tooling. Basically watched all the videos from Stefan, Tom Lipton, Joe Pie, This Old Tony and so on (sure I forgot some channels) and then again stumbled upon your videos and finally managed to understand most of what you said. Its a real pleasure to watch your videos and I learnt a lot by doing so multiple times ... even if machining is just a hobby to me it has become an important part of my life for me and thats mainly because of you and Stefan. I think you are improving the life of a lot of people. Keep on turning :-), ATB Stefan

Put the kids to bed, kill the phone lines. Brace yourself for a proper learning session. Robin, the way you integrate planing and execution, theory and practice ist just wonderful and so accessible that it always makes me believe I could achieve something within this realm of precision. Of course there's it's only wishful thinking still. Thanks a lot professor.

As a hobby machinist, a lot of what you are going on about is way above what I FULLY understand, but you relay it in such a way that doesn't make me feel like a complete idiot and that is very much appreciated. Keep up with the excellent content, it's greatly appreciated

Buck chucks are good tools to have. I have seen the distortion you have shown, my approach has always been to loosen all the adjusting screws and move only the one I need to move it in the direction I needed it. Then loosen it again and adjust the others as necessary until I get it running as needed. Always loosen them after adjusting them. Once the chuck is adjusted where it needs to be I snug up all the screws, one side then the other mindful to be deliberate to not skew the results.. Do this to secure the chuck in position being careful to avoid distorting the chuck while maintaining the concentric adjustment. Done it this way for the past four decades I machined and always teach others this method. This method works well and is quick. Nice chuck you have masterfully built thank you for the video.

It's funny when you're mentioning Dan at the end of the video having an improved version after you're giving a ton of details how you improved you're chuck.

Impressive as always - so much going on. I think I may need to watch this several more times to force it all to sink in 😁. Thank you Robin.

Robin, you truly are the goat when it comes to this stuff. You should have millions of subscribers just off the knowledge you have and all the little gems you throw into each video. I have to watch your videos multiple times to catch them all. I very much appreciate you for all your hard work, especially for putting this all into a video for us to watch and learn.

Rebrenz, I am an electronic engineer and I understand only 50 to 80% of what you are saying. The main reason I watch your videos is the passion and the motivation you put in your job. It inspire me in what I have to do. There is only way to get stuff done: pure and crystal clear perfection... or at least always try to.... Many thanks from Italy

Robin, you are truly brilliant. Thank you for revealing the why's of your design choice - extremely valuable insight for those of us learning the art of engineering. I can not express my appreciation for being able to learn from you. This chuck is second to none, which seems to be a standard for your work.

I’d like to send a big -thank you- to you for spending so much time over the years teaching the internet awesome things. I spent seven years at a shit job soaking up all this info 8 hours a night and built my own cnc shop at home a few years ago. I learned enough from people like you to finally score a CNC machinist job which is damn near unheard of in my area. Starting a LLC this month also in hopes of putting my own products out in the world. So thank you again friend. P.S it’s probably your fault the boss kinda got at me today and told me not to make a masterpiece out of every part and “just debur the damn things!” Was running the mill, cmm and deburing simultaneously. Got a little in the zone. But they Rob Renz smooth, better believe it.

Watching your work is a type of religious experience. Thanks so much.

Great to see you back in action. We shared this video on our homemade tools forum this week 😎

Another gold standard project Robin. I sometimes use those high-tensile socket screws as stock for making parts, I hadn't thought that having forged heads would make them even stronger. So many insights in your videos.

Wow! It was a pure pleasure to watch this video. There is something magical about the way you share your rich, brilliant insights. Thank you for sharing.

This is like next level coloring outside the lines. Outstanding Robin. I do so enjoy watching and learning from someone who is really really good at what they do no matter what their discipline may be.

Robin, That was awesome, in the true sense of the word. So many bite sized pieces of knowledge. Thank you for your willingness to share every important detail from start to finish. Your dedication to both your work and educating others is inspiring. Kind regards and best wishes, Reuben

Very cool design and some great tips. I’m adding this to my list of shop projects. Thanks for sharing Robin, as always very educational.

Your work is carefully thought through and masterfully executed. It was a real treat to watch this video. Thank you!

Robin, glad to see you back! Very nice project love the use of the cap screw as raw material, a nice reason not to chuck out old bolts. Thanks Craig

YAY! My favorite machinist goes space cookie on precision again! I am consistently amazed at how "wrong" my natural senses are about the world around me. My senses tell me that stone, big lumps of cast iron, etc are mathematically rigid, and it is SO intriguing to come along when you break down all the directions in which force is applied to make everything flex like jelly. I'm also pretty proud that, having watched all your episodes, I now have a pretty good "hit rate" on guessing what you're about to address. I totally called it on the amount of stik-out of the back plate in the vice as you were about to machine the opposing edge.

the shot with the laminar flow coolant is an interesting window into the toolmaker subtle flex culture :)

It's very easy to listen to you explain Your processes for an hour. Your thinking process is Incredibly thorough.

Beyond impressive as usual!! Thank you so much for sharing this informative video. Appreciated more than you know!!

There is so much valuable, innovative information packed into this video, I don't know where to start. I built a chuck stop for my 9" SBL based on your design shown at 23:00' and it really is incredibly useful. I'll be thinking about Making A Better Adjustable TIR Lathe Chuck next. Thank you very much for sharing your experience, wisdom and skill. Cheers, F.C.

And still waitin for next video of precision toolroom spindles.. Will be also interesting to see common work and tasks for such spindles in workshop)

Excellent! Thank you for taking the time to show all of this. Like many of your videos, I am sure I will be returning to this. There is always more to learn.

Very nice demonstration and build upgrade, Thank you for sharing. Appreciated you sharing the information about the surface grinder and alignment, I don't currently have one, but perhaps someday. Take care L.L.

Where has this RU-vid channel been!? How have I not been here before ? New sub…. Lets go!! MACHINING FOR THE WIN!

I’m not proud of my machining skills, just thankful that the knowledge allows me to appreciate how many facets of design , solid works skill and precision machining Robin is showcasing here.

Great video and cool design. Also good to call out Gelbart's chuck, he has a lot of cool designs.

Pending watching the whole post, THANK YOU and a special note for showing where you are going first. Bottom line up front is US Army writing, and I often go all the way to the end of a RU-vid posting to see where they're going before I decide to watch it. Kudos!!!!!

Robin the thing I enjoy most about your channel is the mindset that you can make something that would be considered standard “ho hum” and refine it to make it top notch.

This is yet another amazing idea, this is a good one. I suspect chuck manufacturers will build these into the chucks in the future. Remember that imitation is the world's best compliment. 👏 EDIT: this needs to be named a RenzTrue! Amazing how much thought you put into this. Above my pay grade!🙄 XLNT work as always!

"chuck pimping" is not something I was expecting from a robrenz video. 😂

Excellent idea I did someyhing similiar for use on 4 jaw chucks. Only without the graduations and working on the Z axis. We had common jobs that involved indicating faces on parts. As most 4 jaws have tee slots l used the appropriate size tee nuts and hex head screws. The hex head was then tapped for a fine pitch screw. The jack screw could then be used to move the face of the part around. Much better than using a soft hammer or pry bar. The jack screws made things controlable.

Robin, Really interesting video. Most all of the set-true chucks I own don't even have the adjusting screw at 90 degrees apart as well. This makes the even more difficult to adjust. You seemed to have solved most all the problems with this type of system.

Chuck, my pimp. I had to say it. Awesome video Rob. Thanks for sharing.

And another episode of ROBRENZ where I have to stand on a chair so it won't be over my head. Thanks ROBRENZ, I always enjoy and amazed by your content.

Thank you Robin for taking the time to film and edit these super high quality videos! Both the content and the video quality are second to none! I really love the matching ground step height for the back plate, and the pressed in stiffening plate made such a difference. I never knew about the long bolts from the front vs short bolts from the back design detail so the bolts can flex and not impede the skidding. I think of the bolts acting like flag poles in the wind.

Thanks for showing the end product and use at the beginning - helps me follow the build process. Fantastic design and craftsmanship as always!

Its a holiday for me every time you release a new video. I think your statistics will prove that most of us did not skipped a second. Thank you for being an inspiration for me and others like me!

Ok, give an early warning that your mind might be blown away ! I had to watch this in three sections as my mind would stop working.

Another Renzetti tour de force.. Thanks for the lessons.

I was just watching some old video of tour last light. Thinking I miss Robin... I know you are busy. So thanks for taking time to melt my brain. God bless

Such a knowledgeable and skilled man. Teach me how to do life

I have wanted to add thousandth scales to my chuck for years, I just never did it. It is still going good to sit far down on my to-do list but I am glad to see someone do it. Nice to see a new ROBRENZ video.

The effort in detail design and consideration is truly amazing! Thanks for sharing

The only channel I "thumb up" before even watching the content. So happy to see your always-amazing-over-thinking back. Thank you ,sir.

An absolute masterclass, not much else I can say really I enjoyed watching and your simple explanation makes it a pleasure. The old lead mallet seems rather Neandathal now 😂

NICE ONE WOLF IN SHEEP'S CLOTHING. BEEN HOPEING YOU WOULD PUT A VIDEO ON . THANKS BUDDY.

Excellent stuff. Educating and entertaining all rolled into one.👏

I’ve watched a lot of your videos that I know I will never be able to do. But cleaning up the chuck for safety is something I should’ve already done. Just pulled my chuck off and got my jaws out to work on that.

Some years ago I have converted a 6" chuck to make it adjustable. It is a good conversion and I apparently unknowingly avoided the flexing of the chuck body, at least to a large extent. But now, after watching this, I will probably re-visit that to see just how good or bad my design is in this respect. His point about the front of the chuck bowing out, making the jaws "bell mouthed" is a very good one. And his method of reinforcing that is excellent. I mention my experience because, when I say this is an EXCELLENT conversion and video, I want everyone to know that I do speak from experience. Robin has considered and apparently successfully tackled so many more issues that come with an inexpensive chuck. My hat is off to the master! Yes, thank you very much for the excellent conversion and video.

Foresight, beats hindsight by a damb sight. Favourite quote.

Thank you very much for this Rob. Most enjoyable and totally gripping! Wonderful cinematography and piles of mechanical wizard tips and tricks. Your approach to the work is very inspiring. I wish good fortune on all your projects.

Thank you for sharing this great knowledge and especially how everything is "rubber" i work with large diesel engines and it is incredible how a large engine block changes shape just after a few years. Great video 👍👌

When one of these pops up, I save it for a while, like the cherry on top of a sundae.

Wooohhh new robinZ. Damn neer wrecked the truck. Yeah I watch RU-vid and drive. Traffic is dead slow. Roun here. 👆🌍✌️

Rob is a Profectionist!!! I Love it!!!! Well done Again SIR!!

Great video, awesome work. Your comment on Euler loading (and failure mode) of Jobber length drills at 24:30 reminded me that my Swiss strengths-of-materials professor of 30 years ago always made us aware that Leonhard Euler's last name is pronounced "Oiler" (like Edmonton Oiler or Houston Oiler) and promised to fail any of us who pronounced it otherwise. I'm pretty sure he was correct; just thought I would mention it. The first occurrence of Euler buckling assumes a sine profile and would wreck the drilled hole and eventually with higher column compression will shatter the drill bit.

Great video Robin! I think of you as the Dean of machinists! More please!

Re-watching I am getting more and more ideas. I don't really need a set-tru chuck but stiffening the system with two bolt patterns is a game changer IMO. In fact a thing I have been irritated by is the fact that on the chucks I currently use, chips get caught in the annular space between the backing plate and the chuck. It gets worse because the type I have has a keyway. I was thinking about somehow filling up the space with a sealant or something but that would be so permanent it would be a huge hassle when the chuck would need disassembly. Right now I am always taking the chuck off the backing plate when swapping them. Now, I think there is a great opportunity to kill two birds with one stone. First, make a thicker chuck end/ stiffener plate that lines up with the outer mounting surface of the chuck, so there is no shoulder anymore. Then, post-machine the two in assembled condition and add bolt holes as required (for front mounting if that is not already the case). Then, machine the backing plate adding the threaded holes and get rid of the stepped shoulder. Next, mount the to together and indicate on the lathe to run dead center. Take the assembly to the drill and add to conical dowel pin holes. Add dowel pins for future alignment. For disassembly, dowel pins with internal threads may be used for a slide hammer or threaded holes may be added for pressing the pieces apart with screws. When all is done bore the (hard) jaws as is now well known. Notes: - The chuck end/ stiffener plate does not need to be an interference fit per se when the set-tru feature is not added, however I feel that it will only add to the stiffness. The plate may also be fitted with screw holes for push-off disassembly. - Making the end face of the chuck flat will make it very easy. After all making two parts with the same axial dimension on two shoulders is over-constrained by definition, with the set-tru feature it is necessary but pretty advanced skills and equipment are required to do it right.

The fact that robin gets to upload new videos stomp me everytime. Im like "robin is gonna b da first man to make chips in space"

Thank you letting us to look over your shoulder once again. Highly informative video.

Thanks for the video. Hopefully I'll be able to make one of these. It will be interesting to see if the design can scale down to 4- or 5-in chucks. BTW, I've always heard Euler pronounced "oiler".

Even the most experienced machinist will learn something from this video, I learned a ton!!! Thank you!!

Wow Beautiful.. Fantastic design and detail.. Thanks for sharing Robin.. 👍👍

That tap handle is glorious.

Gee Robin, you and Stephan go NASA level on all your projects. Out of this world amazing work you do! How about a 'back to earth' version next time lol.

It's so nice to see you again! Every new one video of yours is a fiesta!))

I never believed in the whole "always use the same pinion to tighten a 3 jaw" until you actually explained WHY it makes a difference

The informational density of The Master POTMAs posts is like that of a neutron star. Many thanks for your punctilious posts.

thanks so much Robin, please know how much your efforts are appreciated!

I use the text layout sketch approach as my standard process. If you were not aware, each sketch text entity creates a floating anchor point (little blue dot). Your text sketch will report as not fully restrained until each anchor dot is fixed. They are visible (printable) , so anchor them someplace strategically - like over a hole.

Thought provoking and educational as always Robin. Thanks for sharing!

👍So much tech info being shared, had to watch it a few times to keep up as always. Your mechanical wizardry sharing is truly appreciated. Thank you!

You sure know how to make a chap feel inadequate, but as alwsys i forgive you! Keep 'em coming and I'll keep watching and never mind the ego bashing.😂

Thanks Robin, enjoyed as always. I have that same Chuck, completely de burred by hand, per your prior video. you have been missed! Cheers!

i love when we have an excuse to over engineer something. thank you robin!

Please post more !

Very nice. Always enjoy watching you work.