Internal Threading On The Lathe!

[@steveman1982]

Thanks so much for this video in particular, it came in really handy in my first attempts at internal thread cutting. And here's hoping your shoulder is back within specs soon!

[@sofiatgarcia3970]

"Forming a committee to start," Love that phrase and explanation!

[@purerhodium]

A note on grinding carbide for other viewers: the dust produced when grinding cemented carbides is especially nasty because it contains a significant amount of cobalt. Inhalation of cobalt-containing dust can lead to numerous acute and chronic inflammatory lung diseases. Concomitant exposure to tungsten carbide is known to greatly exacerbate these effects.

[@bradyoung6663]

I'd like to add even when grinding or welding stainless. The Chromium signs were everywhere at the power plant I worked at.

[@normtheteacher5485]

@@deedeeindustrialsuperprecision same thing applies when melting and casting metal. If you taste metal then modify or establish a ventilation system. I melt lead to cast bullets. DON'T WANT TO BE EATING LEAD!!

[@Kycirion]

One method I found to fully thread a blind hold with taps if you have to, is to take a spare tap and carefully (without overheating of course) grind off the point so you have full diameter threads and a flat bottom. Start the threads with a starting tap, then switch to the flat bottom tap.

[@frankm1776]

You do a really nice job explaining the process of the how, what and why of a given metal working operation. It has helped me a lot. Thank you!

[@irishwristwatch2487]

Also a handy tip for tapping metric threads - its always diameter minus pitch. So something like an M18x1.5 is gonna be a 16.5mm tapping drill. Really handy little trick to have

[@asciimation]

Thanks Quinn! I had to internal thread a ring to screw a dog bone radiator cap into which has a 2" 16 TPI Whitworth thread on it. I have done threading before but not enough to always remember the finer details but I knew you had a clear and easy to follow film on it. Excellent memory refresher!

[@playpool12fyao]

Love you videos. I don’t do any machining but the way you explain things makes it very understandable for your everyday person. Great video. Thank you for sharing.

[@johndufford5561]

Could not have come at a better time! Mucho thanks. Very delicate & precise project coming up for a violin cane. Been trying to figure out how to do this without the tool holder hitting the spinning chuck. You demonstrated it clearly and again I thank you. In my head this has been about a 9.5 on the sphincter factor. Now it's only a 2, which is doable.

[@numeristatech]

Sphincter factor: I’m adopting this!

[@Errol.C-nz]

@@numeristatech otherwise called a botty puck

[@jgunpilot1]

I’m a new subscriber and new mill/lathe owner. I’ll be visiting your channel quite a bit in near future. I love the way you impart information, it REALLY works for me, thanks!

[@davidatkins1483]

Very interesting process. Thank you so much for taking the time to make this video. I found it very informative.

[@bostedtap8399]

Another excellent discourse on lathe work Quinn, the handing of tools (Left and Right hand), is based on the direction the tool approach the material being machined. Thanks for sharing.

[@drevil2783]

The cleanest and neatest machinist on youtube. I fail miserably in cleaning...

[@Canyonman44]

Well Done. I have watched this explained in other "professional" shop class videos, bored out of my skull!!!! Your videos however I can watch with interest. Dunno what it is but keep up the good work and Thanks.

[@floridacoder]

I've been watching mini-lathe videos for awhile because I want to buy one. Your videos are awesome! You explain things in a way I understand. Prior to this video I never considered making my own tooling.

[@lohikarhu734]

Quinn, I do like your channel! Nice to see "Canadian content" of such quality, and , yes, fun! Keep well, keep up the great work!

[@MattOckendon]

Yay, Quinn is back to lathe skills! There are no bad videos on Blondihacks but these are gold dust.

[@gazmeister1984]

This is by far the best lathe tutorial channel around. This birds awesome.

[@StuMitchell-v5u]

Very well done. You are an excellent educator!

[@rjordans]

Had to watch this again, gathering courage for a 49mm × 0.75 internal threading job. Need 3mm deep in a partially blind hole. Gotta love those camera threads...

[@AmateurRedneckWorkshop]

We are in total agreement that single pointing a thread is the most satisfying thing you can do on a lathe. Thanks for the video.

[@ironhead65]

I do not know why I can never remember this, but your trick to using the dial indicator it's such a great idea I definitely have to do something to try to remember that!

[@tom_tom_go]

Loving the continued humour in your recent videos, thank you for taking the time to make them. I am tantalising close to buying my first lathe (yes, buy a lathe first!) thanks to all your supportive content 👌

[@theperl9663]

Thanks so much, I have been needing to see you cut internal threads. I've done a few external, but no internal. Scaredy cat. The reverse feed is the way to go. No crashes.

[@marksanchez8314]

I really like your videos you explain well what you are doing keep them coming take care and stay safe ❤

[@robertmoore4444]

Very good video and through instructions Thank You ! You sound like a seasoned machinist !

[@joeybobbie1]

Another Great Video as Always. You are a Great Teacher and I have watched your Videos over and over again. Thanks for the Videos and keep them coming. I have lots to learn still 👍😁

[@yodasbff3395]

Nice work 👍, I like the way you use of the dial indicators.👍

[@lesmaybury793]

Good video giving confidence to those with a nervous bottom. I'm glad the reverse internal threading was covered. For me it is the less nerve wracking way to do it. I always reverse thread internals because as the cutting side is facing you it can be seen easily. Also if you are cutting externals to a shoulder put the tool on the back if you have room and cut in reverse 😁.

[@mafosa8519]

I had to wear my safety glasses when you made your first scratch pass!! Even then, I jumped back!! Lol! Really great shares! Larry

[@firebird8600]

Yay it's Blondihacks time!!

[@kassilewis5511]

I've actually gotten to where I rarely do a scratch pass to check my gear setup anymore. I just put an indicator on the rear of the carriage set it to "0", engage the halfnut and turn the chuck one revolution by hand. If all is well then the indicator will read that the carriage traveled 1÷ by my chosen tpi. Works just as good for me.

[@TONYJUD57]

Very satisfying to cut Left Hand Threads also, I start the cut from The Back as my Lathe do's not reverse, Keep up the Good Work.

[@philchadwick9470]

Thanks for this and all your other excellent videos.

[@TheFreshmanWIT]

1 suggestion for those reading (That I learned the hard way!)... A big thing you have to 'think' about when retracting your tool on internal threads is how much you can 'retract' the tool, as it'll hit the other side of the hole! I made it hard on myself at the time, I was going deep into a hole (so as large-of-a-bar as I could get away with!), it was the 3rd diameter in, in a blind hole, without a gutter. Typically, I can do all of that pretty easily on external threads, I can do the half-nut-off/cross-slide-out in 1 motion and have no problem. HOWEVER, when doing so on internal threads it becomes trivial to crash the back side of the tool into the other side of the hole, which I managed to do on my 2nd to last pass, ruining the entire threads and entire part. So NOW when I do the internal threads, I set up a 'retraction stop' to keep this from happening! Its a little annoying to setup since you need to 'retract' the cross slide more the greater your depth, but it has saved my bacon a few times since :)

[@BLECHHAUS]

An almost divine feeling when the thread fits :-)

[@bernardkimble1115]

Love your videos great for learning and fun too! Cheers from down under.

[@seanalexander9531]

Another super-awesome video - thanks Quinn!

[@daanwilmer]

I don't own a lathe and haven't even ever used a tap, so this is way beyond my skill level and not something I will attempt in the near future. Yet very interesting and entertaining to watch!

[@kimber1958]

Just start by cutting some external threads don’t worry about what size they are just trying to make something that looks like threads

[@robertoswalt319]

Sometimes it is fascinating just to learn the magic behind the way things are manufactured.

[@normtheteacher5485]

Go to Menards and buy a couple tap and dies that come with the proper size drill bit and do a few threads manually just to get started. Wear eye protection with all metal projects. I was drilling a hole in cast iron the other day and the bit monetarily got stuck then suddenly released while my eye was only 5 inches away. The release shock, shot metal flakes into my glasses and face. SO GLAD I WAS WEARING EYE PROTECTION! The metal flakes that hit my face were both hot and high velocity. Could have been a blinding experience.

[@barryfields2964]

Nice to know you got your grove back!

[@ErnieNoa3]

Thanks for showing this. I like the way you did the blind hole.

[@OchoMiniatures]

ANOTHER great video seriously keep the puns coming!

[@RelentlessHomesteading]

Nicely done and documented. Thankyou Like those blue inserts in your cross slide. Don't have a lathe yet - but learning in preparation.

[@carlwilson1772]

Excellent as always.

[@jimsvideos7201]

Thank you for all the time you put into sharing your knowledge; I'm sure I'm ahead of the curve because of it.

[@Just1GuyMetalworks]

Threading blind holes can be nail biting to be sure 😊. For those with a threaded spindle, I would recommend stopping one thread short and spinning the chuck by hand (with half-nuts still engaged) for that last thread. Takes some of the fun out of it but a lot less nerve wracking lol. Great video as always, Quinn 👍😁👍. Cheers!

[@drewhunt9205]

You had me at "37% more terrifying"

[@schm4704]

For me, "thinking about forming a committee" is what did it 😀.

[@makosharkcnc7730]

Good job! Patreons throw me little love too!!!

[@charlestown4719]

As always a great video! That brass sure does machine like butter. :)

[@roberttheaker6205]

I live in England and a retired engineer but st have a workshop and like watching your videos

[@ssboot5663]

Ha! I very recently bought an older South Bend to replace my very old Atlas with NO quick change gearbox so its easier and faster to make threads. Ive never done it. Its too tedious (no patients)to read the fine printed chart and change gears over and over. Currently doing a clean up and inspection and soon will try threading. Thanks for the great videos!

[@huntereakright8988]

nice blind hole tips, threading away from the chuck is thought to be more sturdy and prevents chatter, since once chatter starts (threading towards) harmonics will keep it singing

[@foxwood67]

You read my mind. Danger and anxiety are thoughts i had. Well explained but looks a bit intimidating. Not a machinist but really enjoy your content.

[@manusalinas3994]

You can grind a old used hacksaw blade to a taper point and use as deadnut point. Clamp it to the right side way wipe.set your cutting tool at the end of blind hole or shoulder. White paint a mark on lathe bed near end of point. Scribe a black dot on mark. That will the stopping point for disengage the thread action .old timers like me call it blind threading. Front threading made easy.

[@ADBBuild]

I'm excited to see what you are making that uses this technique. An alternative to grinding an "odd" tool is just flip your regular tool upside down. Then you can even run the lathe in the forward direction. It does transfer the cutting forces into an upward direction, which can be bad, but on small threads this shouldn't be a problem. You do have to feed into to part though or else you would cut a left hand thread.

[@Roy_Tellason]

That part about "lots and lots of light" when you were grinding seems to apply to a fair amount of stuff for me in recent years. The more years, the more it seems to apply.. Thankfully high-output LED lights are getting cheaper these days, and I've homebrewed a couple of them as desk lamps. Gotta get some over my workbench, too. I was told by my optometrist that this has something to do with how old I'm getting. But I ain't getting old, nope! :-)

[@richardepps8500]

Really hit that intro on this one

[@henritheron3050]

You are a star! Need to do this at college this week. Could you please give a link for your long travel dial indicator used in the video?

[@Blondihacks]

That was a donation- I don’t actually know where it’s from, I’m afraid

[@henritheron3050]

@@Blondihacks thank you for responding:) thought I remembered that but couldn't find the video. Was nice rewatching everything when I tried though!

[@321ooo123]

Still didn't put together clough42's ELS? It's a game changer! I have printed mounts for the stepper/rotary encoder with PLA on a 3D printer - and still waiting when it's going to break - and it still goes strong. No more changing gears for me! Definitely worth investing a couple of days to get it working.

[@MrBlackbutang]

Absolutely Feckin Awesome

[@bearbon2]

I cut internal threads by just turning a regular internal thread cutting tool to the back, cutting with the bottom of the tool with the lead screw set to cut on the out stroke. This also allows the spindle to rotate normally with no risk of loosening the chuck.

[@56COLWOOD]

Had to make 100 each 1-12" stainless steel bolts and nuts once at work. For a pulp press. I made a boring bar with the 30 degree and ran it upside down and in reverse for the nuts, Like you said, it took out the pressure or anxiety of crashing the work. Thanks for the video. Awesome watching!

[@jscancella]

Dad joke: but those mating threads, do they mate for life? You could say you're the love matchmaker for threads!

[@joaquinpendleton8470]

Hi Quinn: Love all your videos. Question. You showed how to turn the external threading tool upside down to thread away from the headstock. With the lathe running in reverse. Can't you do the same for the internal thread job, without making a seperate tool? thanks, Joaquin

[@TandaMadison]

Going into this video I'm thinking, "Now there's a video with a lathe and simple ground tool, I have both, no chance of tool envy"... not even three minutes in, "damn D-Bit Grinder, how have I lived this long without a D-Bit Grinder". Hahahahah. Wonderful video as always.

[@Blondihacks]

They are fantastic little machines. I blame Stefan for getting us all addicted to them. 😂

[@624Dudley]

I wish I knew how many D-bit grinders changed ownership because of Stefan. I bet it’s lots…

[@bradyoung6663]

Nice. If you want to revisit this sometime, you could do the left handed versions. They're mostly the same, but the tools are upside down.

[@larryschweitzer4904]

Just in time, I need to cut a 16 tpi internal in a piece of 12L14. I've only got a 5/8" hole to work in. I have some O-1 steel rod to make the tool. I have a D-bit grinder. Will attempt to harden and temper. Will thread from the chuck out. Wish me luck, I'll need it.

[@antontaylor4530]

I haven't seen you do any time travelling with your lathe, do these lathes not come with a flux capacitor from factory? Or do you need to get This Old Tony to help you reflux yours?

[@laurieleyden3654]

You will need easy chron 3 flux, which will be available in 2042 from time flux UK.

[@x8rsrule]

A thought we all agreed on keeping that a well kept secret...

[@IBWatchinUrVids]

Hey @Blondihax - make yourself an extension for your Dbit grinder, then put the diamond cup wheel on backwards ^.^

[@taranson3057]

It’s actually more like 37.50% more terrifying. I have the tooling for this but I have yet to give a go. This video surely will help calm my nerves.

[@wallymurray620]

Love these videos, really hope to soon take this up as a hobby. Hope this isn’t too dumb a question but can you do a single point, pipe thread(tapered)with a lathe?

[@manythingslefttobuild]

4:52 Yes, that's exactly what I thought your lathe sounded like.

[@manpaa2225]

As a casual observer I have a question, probably a stupid one as I have no machining experience, but why not start closest to chuck and cut outwards? Wouldn't this eliminate any fear of crashing into the workpiece?

[@JulieanGalak]

Any plans for more beginner lathe videos? There are two topics I'd really like to see: making holes with a boring bar, and using a faceplate to machine non-round parts, like castings. You may have talked about these in some of the other videos, I'm still working my way through them, but I think specific skills videos for these topics would be excellent.

[@Blondihacks]

Check out my Lathe Skills playlist!

[@AMRosa10]

When you sped up the video, I could have sworn I saw Sprocket's paw extending over the chuck and swiping at the workpiece as if to say "Not that way!"... although maybe it could have been "Stop this and feed me."... or "Even though this is threading, I'm bored and want to play with shiny spinny thing..."... but I also may have been hallucinating... 😼

[@zuthalsoraniz6764]

A question regarding the threading in reverse: On better lathes, is there an option to reverse the direction of the leadscrew without reversing the direction of the spindle? Since that should allow you to thread away from the chuck while using a "normal" threading tool. Edit: I am maybe not the best at spatial reasoning, but while doing that with the normal tool orientation would cut left-hand threads, shouldn't cutting away from the chuck, with the spindle running "forwards", but with the tool flipped 180 degrees and thus cutting on the far side of the part produce a right hand thread again?

[@robert_g_fbg]

What you describe would cut left hand threads, the lefty-tighty righty-loosy kind.

[@zuthalsoraniz6764]

@@robert_g_fbg Ah yes, of course. Damn you, chirality in three spatial dimensions!

[@ShaodiHuang]

It's possible, but you end up cutting left handed threads.

[@terrybuydos8489]

I need to watch a couple more times, but ,other than visibility, is there any reason not to do the blind hole threading in the forward direction starting from the bottom and working out?

[@douglasbattjes3991]

Quinn, If I cut the internal threads in reverse travel with the first tool you made from inboard to outward am I going to get left handed threads? Thought I saw Joe P cut then in that direction but he turned the tool upside down and ran in. If the travel goes either way won't the threads be the same as feeding it inward? I'll have to try it and see what happens. 👍👍👍👍🤞🤞

[@SenorGonzo]

Today I learned I have a bad attitude. Spot on, but it still hurts.

[@28drafting]

What got me interested is the idea of 28 mm threads, inside and out, in plastic. A plastic water bottle type thread. Any advice or info?

[@DAKOTANSHELBY]

Jokes on me! Just watched Clough42 on sewing a dust cover. Then saw your just released video. The still pic looked like a sewing machine in my mind and you referenced threading. Thought you were duplicating Clough42, but no. Thanks for your great videos!

[@RinoaL]

Cool!

[@danielparker6102]

For a person that plans on using the lathe for mainly making rings and turning 4" threads for large wooden jars; What lathe would recommend for that and possibly for growth? I have been looking at the g8688 Grizzly lathe. What do you think?

[@oldhick9047]

Who's in a panic, I knew you were on the case.

[@majormalfunction5101]

Can you sharpen end mills with your drillbit grinder?

[@evilscience3164]

Cutting with a left hand tool with the lathe in reverse is called "The left handed Rhodesian reach around."

[@MermaidSystem]

In order to this topic, there is a Electronic Leadscrew Project. What do you think about something like this? I'm considerin this for my Lathe.

[@hiranosoranouta9223]

at about 13:20, you start cutting in reverse, but how do you know that the starting point of that "other sided" cutter is in the right place to line up with the threads that you have already cut??

[@thedroolfool]

Set the compound before you do the boring and you can put a nice 60 degree leading chamfer on the hole.

[@lohikarhu734]

Do you mention anywhere that you need a specific mind of grinding wheel to do Carbide...I think?

[@MrCrispinEnterprises]

Good tips.

[@bbailey0625]

What is your compound angled at during the internal threading, 15 degress?

[@shanel4348]

Hey Quinn, I saw in a video somewhere where someone was doing internal threading and would reverse direction once through the through hole of the part, and then feed back out while also cutting a small amount of material on the way back out to save time. I know this isn't necessarily the conventional way, and not every lathe can go reverse (counter-clockwise?), but what are the downsides to doing this as a time-saving measure? Extra tool wear due to the pressure being applied to the back side of your tool? An interesting thought at least. Oh, and I mean specifically while threading, I know you can boring bar in reverse all day without any major issues.

[@carbonunit6573]

Why do I feel that if the zombie apocalypse actually happened I would really want you on my team.

[@chrisj4570g]

Nice job, you Fancy Lass you. 👊

[@jmanthatsall441]

What type stone were you using , the white wheel?

[@marctrossbach6560]

Thanks. Super helpful

[@paulmorrey733]

Thanks Quinn

[@CraigBilodeau]

I saw the title of this video and was expecting to countless Douglas Adams references. Not seeing any, I’m now wondering if I was simply projecting my own warped sense of humor. 😂

[@andrewedgecombe]

(Total pre-noob question) When you’re threading toward your chuck, in the “normal” direction, much much tolerance is there for the time critical operations? Eg. At normal speeds, how long have you got between “the cutter cleared my part” and “I’ve just suffered a powered collision”? Another eg. How long do you have to engage the half-nut when you’re watching your thread dial? From the outside they both look like they’re microsecond precision operations,

[@JaborWithaY]

For cutting a thread in a through hole, you get to choose how much time you have between the end of the cut and the carriage crashing into things. The further you have the cutter sticking out from the tool holder, the more time you'll have - the complication is that of course with more stickout you have less rigidity. Generally you'll set it up so that you have enough time to comfortably stop everything, but no more than that. (Things can get tricky if the thing you're worried about is the cutter hitting part of the work piece that you don't want to cut - when you're machining a part to a spec, you often don't get to choose how much gap there is!) The timing on engaging the half-nut is basically one rotation of the lead screw - this is going to depend on how fast you're running the lathe. If you try and engage early in the rotation the half-nut will just rest on top of the screw thread, and if you just hold gentle pressure at that point then it'll drop in on its own at the right time.