LATHE CHUCK MAGIC TRT#5

How to get optimum performance of a lathe chuck by properly loading the jaws before boring or grinding the gripping surfaces.
#practitioner_of_the_mechanical_arts
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[@williamdinisco8081]

Return of the King

[@peteroleary9447]

The man with mental FEA. He sees tenths in colors.

[@StefanGotteswinter]

I was already rewatching all of your and Toms old videos. And then there it is, a new video 😀 Thanks for doing such a thorough description on boring jaws, picked up some new hints from it.

[@howardosborne8647]

That reminds me I have some catching up to do with the last 3 videos on your channel.

[@StefanGotteswinter]

Oh! And thanks for the pipe chuck key - Made one years ago after you showed them first. And its so nice compared to a regular one.

[@Watchyn_Yarwood]

So when can we expect a similar video from you?

[@howardosborne8647]

@@Watchyn_Yarwood To be fair to Stefan he has posted quite a lot of regular video content onto KZbin recently. I had failed to catch up with his last few because of being distracted with other matters.

[@mftmachining]

Exactly the same here, Stefan. LOL🙂

[@ThisOldTony]

Enjoyed! Great to see you pop up again. Do you sell that purple CBN? Willing to pay a little extra of course.

[@mattdixon8750]

Great video Robin tons of info per usual, and sorry T.O.T. but if you have to ask... We'll you already know. Take care you two. Thanks!

[@ryanshadders750]

We miss you too! Hope you had a great Thanksgiving

[@Timothyh3nry]

You have to be careful of that purple stuff, degrades terribly during time travel. I have some pink CBN which can withstand temporal displacement much better. Happy to hook up a fellow traveler for the right price.

[@st3althyone]

ToT has joined the chat. Glad to see you’re scurrying about in the gutters of the interwebs. 😂😂

[@ROBRENZ]

Thanks watching Tony! ATB, robin

[@brucewilliams6292]

I sincerely appreciate your putting the effort into explaining the hows and whys of this process and all the other things you have contributed to making the rest of us that bit better a machinist than we every would have been without you. Thank you!

[@ROBRENZ]

I appreciate that!

[@Awegner176]

I used to work with an older gentleman at my first job who was 84 yrs old. Started at age 14 in Germany, came to the US to find better work. Between you and Tom Lipton, I feel like I still get that kind of education that those 70yrs of experience used to teach me. Thank you for what you guys do for the rest of us. Can't find much experience like this anymore... especially not for free!

[@ROBRENZ]

Glad you appreciate the content.

[@kevinbaird9763]

I loved the last tip about making the 5C mounted chuck adjustable. Thanks so much for your time and effort producing these videos.

[@hashgeek929]

I really wish I could give a thumbs-up every time I learn something in Robin’s videos. This one would easily get 5, and I’m not even done watching!

[@TurboDog73TX]

Man Robin, You never ceases to bring the goods with USEFUL information. Thank You.

[@bigmotter001]

Nice to see you back at it Rob! Looking forward to more videos as you have the time! Thanks for posting and take care!

[@SPDLTD]

Excellent video Robin! It would be awesome if you would do a 101 video on cutting/soldering/grinding Carbide and CBN tooling. Materials, techniques, fluxes, solders, temps etc!

[@ROBRENZ]

Great suggestion!

[@907jl]

Good to see you back Robin, and great content as usual. Very unique(and clever) way of trueing chuck jaws!

[@st3althyone]

Enlightening as always, Robin. Thank you for always providing such concise and precise videos as are required in machining. Your content is second to none.

[@ROBRENZ]

Many thanks!

[@bob5074]

Another brilliant solution to a problem I’ll never have, as I’m not a machinist. These videos make you smarter no matter your vocation.

[@user-tw9io9nz2m]

Our patience has been rewarded, welcome back to KZbin Robin!

[@waynepegram3262]

Always pleased to see a new Robin video sharing his vast knowledge with those, "me", less fortunate mortals!

[@kundeleczek1]

It was long dark night Sir, but you bring us sun.

[@johnmcnamara3719]

Gee its great to see you in the shop again Rob. I always look forward to your work. There is another way to load the jaws on a chuck for grinding or hard turning. Take 3 equally sized .5" (12mm) thick rectangular blocks of say 4140 although mild steel will work also, they all have to be the width you wish to space the jaws at. Then fit them between the outer ends of the chuck jaws a bit of a fiddle but not hard. Then tighten to the level you want. Lastly bore the blocks and the jaws together. No need to alter the jaws! I have done it and it works.

[@carlhitchon1009]

Not sure you can be guaranteed equal pressure on the jaws that way.

[@johnmcnamara3719]

Assuming the chuck was made to high accuracy, and most are, and the blocks are also made accurately to the desired width, it works fine. What we are really doing is forcing the outer edge jaw key against the back face of the slot in the body of the chuck and the inner edge of the jaw key towards the front face of slot in the body of the chuck. Thus taking up the looseness allowance made by the chuck manufacturer necessary for it to slide. also any wear in the key and slot that holds the jaws. It will work with any number of jaws above 2 Forcing them this way gives preference to the front gripping part of the jaws. This stops any lateral movement of the part while turning caused by gripping errors. Particularly useful with older slightly worn but still serviceable chucks.

[@summerforever6736]

No cannot be true!! HE IS BACK WOW!!! THE BEST OF THE BEST IS BACK! THANK YOU!

[@artmckay6704]

It's been a long time! Good to see you back! Definitely, this is the right way to true up chuck jaws! Absolutely! Hopefully Ox Tool will make a reappearance as well...... Thanks for another wonderful tip to make our tools perform like they were meant to! :)

[@purerhodium]

Tom's etching press vs Robin's surface plate, which will outlive the Sun?

[@emiliog.4432]

Yes. The legend is back. 🎉.

[@brianevans1946]

Welcome back Robin, we missed you.

[@Garthinyus]

Great teaching from the Master Machinist! You class is my favorite. May the Lord bless you richly for the wealth of knowledge that you freely give!

[@ROBRENZ]

Thanks, you too!

[@johncarey9149]

I'm not a machinist of any sort, but I do have a background in Structural Engineering which means that I can understand your comment about everything being made of rubber. However your videos always fascinate me , for the way you consider, then explain the processes so simply and clearly. Thanks, and it's great to see new content

[@r.j.sworkshop7883]

As always, thank you for an excellent presentation of the nuances to any subject that you are covering. Not just, do this then that 'cause I said so. Very well done.

[@ROBRENZ]

Much appreciated!

[@roadshowautosports]

You sound like a magician! “That’s why we have this other ring!” 😂😂😂😂 GREAT VIDEO ON YOUR TECHNIQUE THAT MAKE A LOT OF SENSE, as I’ve thought it should be but being an apprentice, I couldn’t figure it out how to load the internal faces for fixing them. Difference is that I’m dealing with a couple watchmaker lathe, one antique, and the other an used Sherline. I’m suspecting that the Chuck I have isn’t an used Sherline branded but an used import, hence the reason to repair the jaws, what your method came to shed some light on my endeavor. Now, off to find those damn ball bearings in the right size!!!! 😂😂😂 thank you very much for sharing your vast knowledge on an art that must be kept alive beyond pressing the buttons to run a program in a CNC machine but using real brain muscle instead!

[@lancer2204]

Another master class, thank you.

[@ROBRENZ]

Glad you enjoyed it!

[@jasonh3109]

Another gem Sir. Thank you for continuing to support the community and share your endless amounts of brainpower! Happy holidays!

[@corashy1950]

You can't imagine how many dirty jokes I can get out of this.... lots of knowledge.

[@simonsaelaertfurniture9883]

Please never leave us out here that long in the dull,uninteresting KZbin universe again Robin

[@glennfelpel9785]

Like you, I too have SolidWorks and SolidWorks Simulation as well. It is fun and quite interesting to model things such as a chuck assembly and apply the loadings you describe to the assembly and then of course exaggerate the displacements grossly and visually see the distorted shapes of things. Things behave just as you indicate, you have a keen dye for how things distort. Will say there has been times I was surprised, they didn't take the shape I has anticipated. But then when you actually see the shape it will make sense. Excellent video indeed. Very well done, thank you.

[@ROBRENZ]

Thank you!

[@mshaw290808mi]

When ever I want to see the right way to do things, this is the channel I come to!

[@zitaconstructionllc2230]

I haven’t even watched the vid yet. I just wanted to say that I missed your content. Glad to see you back sir

[@williambramer8217]

Fantastic as usual. I love your attention to detail and clear explanations of the forces involved. Hope it is not as long to the next video!

[@broheim23]

I now fully understand why Quinn coined the adjective "Renzettiness." Excellent work, Robin!

[@ShainAndrews]

Who?

[@carlhitchon1009]

@@ShainAndrews Get a clue Shain.

[@ShainAndrews]

@@carlhitchon1009 Why don't you step up and try...

[@Ddabig40mac]

@@ShainAndrews, Blondiehacks.

[@ShainAndrews]

@@Ddabig40mac Gotcha. Not a fan of her work, and I was trying to think of a guy instead. Frankly I didn't know that was her name. LOL.

[@tonyking9235]

NICE ONE ROB SHEEP IN WOLF CLOTHING. MISSED YOU BUDDEY .

[@Metalloys]

Rob, GREAT to have you back ... REALLY ! Cheers.

[@adam19890911]

New ROBRENZ video, don't blink.

[@shawnhuk]

I’ve struggled with this in the past. I couldn’t find/figure out a method to load the jaws. I made a ring but it wasn’t sufficient and my grinding rig was poor, especially the stone. I made everything worse. The ball bearing race is a great idea. And mentioning the accuracy of the scroll is huge. Ive banged my head off the wall before with a cheap 6 jaw chuck I use. I modified it to be a bolt thru design in order to use it like a set through by relieving the outside of the locating hub on the back plate a few thou to allow adjustment. All great info as always, Robin. I’m always learning something from you.

[@BalandaevVladislav]

Hello Robin! I'm glad to see you. You were gone for a very long time. Constantly visited your channel in the hope of seeing new videos. I am writing a message with the help of a translator, I do not know English, but your videos are clear to me without translation. Thank you.

[@nameofdane]

Thank you for the highly detailed description of process and your reasoning. Always appreciate the density and tight editing you put into your videos. Every chuck we have for our Hardinges at work are badly worn to the point I don't consider using them for first ops, much less anything where I need repeatability. Very very frustrating, but I think now I know what I need to do.

[@davidcolwill860]

Thanks Robin, As usual a gem that I will no doubt revisit.

[@dizzolve]

This is a great topic most everyone can benefit from. Nice

[@SteveSummers]

Thank you Robin😁 Beautiful work . I love the detailed explanation. I have that same 6" Buck 6 jaw and I really like it.

[@slausonm]

I always enjoy seeing your videos. They inspire me to improve my accuracy. Loved the freebie at the end.

[@russelljohnson6243]

Very nice master class on lathe prep for accuracy! Very valuable information indeed! Most machinists on KZbin need to study this.

[@dizzolve]

2:52 these few clips here were really well filmed. Thanks for the great close ups

[@ROBRENZ]

Glad you enjoyed it

[@deepwinter77]

He'll yeah 👍🏻 So happy to see this in my Feed Thanks Robin

[@number2664]

Another point to add is using different pinions around the chuck will give a different result also. I agree most parting and vibration issues are chuck related. I use a strip of paper around the front of the job in a pinch. Bell mouthing also affects tool posts and tool vibration.

[@ROBRENZ]

Yes, only use one pinion if it has more than one.

[@bigbattenberg]

Just thought about the paper trick only hours ago. Gauge foil is an alternative. Will try that one tomorrow!

[@MrCrankyface]

So happy to see a new video from you. Always incredible content, thank you!

[@sharkbaitsurfer]

Brilliantly explained and executed, I do like the appreciation that all the metal is rubbery under tension loads to some degree, and to degrees that matter for accuracy and precision.

[@gbowne1]

Nice one Robin! I had to have my faithful go to chuck face ground and OD ground and new jaws made because even though its a fairly high precision chuck, especially made it look like a washboard from many years of it being torqued to limit into workpieces.

[@first_namelast_name4923]

There are many things you show in your videos that I have no chance of using in my very modest, tiny workshop. I love watching them anyway, because I always learn interesting and useful things. THIS video is different. Everything shown is extremely useful. I have used very similar method (hard-drilling the jaws for pins) to grind in my lathe chuck. Thank you for taking time to take us to your workshop.

[@whatupg1]

Your attention to detail is phenomenal, simply awesome. Thankyou Robin

[@brianbob7514]

Great to see you back, thank you for your time and knowledge.

[@jobkneppers]

Rob, another great episode full of useful and valid information! My C5 chuck is going to be modified just as you did! Thank you Rob!

[@wheelitzr2]

Seeing that Shars indicator on this channel is fantastic! Go Shars!

[@corbin72]

So glad to see you back.

[@williammills5111]

More 24K gold. Thanks, Robin!

[@billglenn10]

I remember the old inspector at McGuckin & Pyle, named Jim Bailey, grinding chuck jaws on the non-adjustable 3-jaw chucks. He used a similar method with rings & collars and used a tool post grinder. He would consume several cigarettes in the process and drop them in a pile on the floor. The good old days 😊

[@ROBRENZ]

Hi Bill, good memories from that place!

[@andersjjensen]

Hi Robin! Nice to see you upload again. It's always fascinating to get a glimpse into a mind that thinks in precision.

[@MachiningandMicrowaves]

Excellent video, thanks Robin. I reground the jaws on my 1980s Pratt Burnerd 8 inch 3-jaw because I was having chatter issues. I used pins and a ring to apply the preload at 45 mm opening with a 38 mm dressed stone on the toolpost spindle and it worked superbly. I mapped the runout across a wide range of diameters using a range of turned and ground bars clamped using the 'O' jaw to see how terrible the scroll was. It's near-perfect from 35 to 65 mm, and below 18 mm, but there's a section around 25 mm that's well off, I bet that was the size of most of the production jobs this old Colchester 1800 was used for. I wish I had an LVDT indicator so I could map the thing electronically. I just have a cheat-sheet listing the problematic diameters where I might need to re-true the chuck.

[@roverinosnarkman7240]

This is the clearest explanation i have ever heard about this problem. Well done! Thank you. I would love to see a follow up video on your surface plate resurfacing project- how it is holding up and anything you would do differently and so on.

[@Jake-zc3fk]

Nice to see you back Rob!!

[@craigs5212]

Thanks Robin, glad to see you back.

[@George-bb9yi]

Thank you for this fascinating video and welcome back to KZbin videos, you were missed!

[@Timeonabike]

Oh happy day! Welcome back Robin! Have missed your particular outlook on things very much. Another great video. Thank you!

[@HM-Projects]

Good to see you back, thanks for sharing

[@CVSBobby]

Man I'm glad to see you back!

[@TheeGrandmaster]

I see robin video, I click video, no questions asked. Thanks for making us all that bit better!

[@taranson3057]

Very interesting video. Welcome back!

[@IGBasov]

Nice to see you back with new video Rob. Thanks!

[@michedmck]

Thank you for an excellent and clear presentation, Robin! Whilst machining, we can tend to go into “auto pilot” mode and stop thinking about all the forces acting on the parts and the jaws. This really woke me up again! The part I found especially thought-provoking was the runout after the machining of the jaws being attributed to the accuracy of the scroll. Thank you once again! Keep up the great work!

[@Heles999]

Glad you are back!

[@graemekgtiger7450]

Hey Robin, thank you for all your time and effort producing these video's. I do appreciate it and are very happy to see your back in the saddle making high quality content again. Much appreciated. 😁

[@bid6413]

Always stimulating and challenging. Thanks, Will

[@theromihs]

Great advice, as usual. Thanks for sharing Robin.

[@jamesdavis8021]

I am glad to see you return. I sincerely hope to see more.

[@gyrogearloose1345]

Great to see you again RobRenz! And thanks for this particularly - loaded with insight and information. You know initially I was thinking "got to have some diagrams here" to clarify the deforming moments and so on. But actually I found a great value in really thinking hard about the details, re-watching some segments of the vid, and gradually getting (pretty) clear what you were getting at. Thank you very much, and please come back soon !!! Best wishes for 2023 and onward.

[@reinierwelgemoed8171]

Wow what n surprise. Awesome to get another video from You.

[@jamesallen3799]

Thank you for returning

[@russtdodd]

I really appreciate your mental process and awareness of “systemic precision”.

[@sky173]

Thanks for sharing this. As a hobby machinist, you've brought to attention some things that I didn't even think of. It's time to grind my jaws.

[@raymondmarteene7047]

So much information in a short video, Thank you for your generosity in teaching. Cheers

[@balesmachine]

I've seen an alarming number of videos that show clamping down normally onto a spacer to grind the chuck faces. I always thought this didn't make sense to me. Your explanation was very simple and DID make sense to me. Thanks

[@jrkorman]

For me it's only a hobby and yet very instructive to see how "it can be done". Glad to see your video pop up on my notifications!

[@glennfelpel9785]

This is strange, just today I was going over your D-Bit Grinder videos as I just got one for myself. Now a new video. Well, I should have done this sooner.... Thanks for this one. Good to see you back.

[@kevinreardon2558]

Good to see another precision video coming from you. Thanks.

[@glenfeane2265]

Nice to see you back hope everything is good love your videos from Ireland you and Tom the best

[@russtuff]

Nice to see you again. Great video.

[@josephlovell6951]

Glad to see you back... love your videos

[@thefekete]

Glad to see you back! Can't wait to watch😆

[@CRILIKk]

So much knowledge & experience, thanks for sharing 🙏

[@MegaCountach]

Great stuff Robin! Always learn valuable methods from you, cheers, Doug

[@Shawn_speed]

Always an honor and a pleasure. Thank you.

[@greglaroche1753]

Your videos are great. Interesting and very informative. Thanks. Please keep them coming.

[@mattyboyace1]

Hey thanks Robin. Did mine today. All from this video. Came out great.

[@DetroitDiesel671]

The only other channel where a new video is as exciting as new material from ROBRENZ, is Clickspring.

[@tomthumb3085]

Hey Robin, great to see you back my friend. As always, this is a great video to watch. Let’s have plenty more.

[@mikemarriam]

Four months. I'm missing me some new Robrenz content.

[@johnspargo5876]

Thank you Robin. Christmas Treat! Wonderfully thorough and clearly explained. Kind regards from John Spargo in CapeTown