Better, Best or the VERY best! Lathe Cut Off made EASY! 

An essential basic principle of welding often neglected by welders that I have seen on RU-vid, is to bevel one or both of the items to be welded. You welded a fillet weld and then removed most of it, leaving only what limited amount of penetration was created. Simply griding a bevel on the edge of the square stock produces a groove weld, which will be much stronger.

You may have been better off to cut a small 1/2" relief on the back of the tool and then use countersunk screws run into threads in the tool. The relief would take the torque and the screws would hold it tight.

well it's a lathe ru-vid.comUgkxN9zrzkkhnjUF5PQbuA_B1gYdsfCu9k6z but it wasn't what i would have anticipated. Headstock, tailstock, carriage apron are manufactured from aluminum now not cast iron. The spindle diameter for the bearings is too small allowing for a few play in the spindle so I am using some blue Loctite to take out the play.

Great idea. I always have issues cutting off on my lathe. I'll have to give this a try. Thanks for sharing.

Old Old timers: We dont know much but we make fine tools that last for generations. New timers: We know everything but we make fine human waste that last for generations.

Thanks Mark. Was that just mild steel stock that you used? Seems completely counter-intuitive to make a holder designed to flex like that. Undeniable results though.

Once again thank you Winky for inviting all of your friends from around the world to come and visit with you in your shop, always enjoyable! I always enjoy learning something new.

Dang Winky that was a great video. You are definitely right about the guys who came before us being clever. I had a feeling that there was going to be a second YEE -- HA with the results that you achieved. Showing the concept behind it with the paper cut out was very effective.

Like that! Thanks for sharing 👍 🇬🇧

I've got one of those Armstrong cut off holders, languishing in a drawer since I got my qctp. I'll have to break it out and have a go. Interesting vid, thanks Winky!

Are plans available for the Very best cut off blade holder? I sure would like to build one. Tnx

Gday Winky, this new parting tool works a treat, all the theory adds up, great job mate, Cheers

I've always had issues parting steel. Yours works great, have to give it a try!

The important thing to remember about old timers is that they have crossed this bridge long before you got to it. The best way to cross it has already proved itself.

I did one also, then YT showed your video. I called bulldog cutter.

I've seen people use countersunk screws to hold the 1/2" square piece to give a clean join.

Very nice, that's going to get copied! I've been thinking about making a parting tool holder for a while! The original clamping set up pulled through from the other side, that would give more chuck clearance. Cheers, Matthew

That was super interesting. I wonder if the design could work on a soggy mini lathe? 🤔, always a problem with those machines made from Chinese rubber 😉. A project for spring me thinks. Thanks for another great idea.

i maid all mine out of a old forged spanner

I don't like the clamping mechanism for the cutter since it means you need lots more clearance between the chuck and the cut-off line. However...the total LACK of any chatter at all was impressive. I think I'll have to try making one of these. What kind of steel did you use?

I liked your vertical sawing attachment. Very nifty. Also you did a great job of explaining your PT approach. Thankyou.

Awesome work! Been following your parting exploits, and I agree this is the best one yet. I think I'll be replicating this somehow, for my 7X mini lathe. Cheers!

For sure the thickness you used had to be a guess that it would give some flex but not too much. Maybe should have ground the corners off your square bar to make a v-weld not a fillet to insure it held solid.

Please SIT DOWN before turning on the band saw. Falling/slipping into the blade, ugh! Also, lower the blade guard Safety First and Always! I didn't watch beyond the band saw episode.

Over the past fifty-plus years, I have found cutting off to be a pain. Inverting the tool, and either cutting from the back of the part, or reversing the spindle while cutting from the front side, has given good results in most cases. A threaded spindle can cause anal puckers if the chuck unscrews. Your new design looks interesting. I shall follow to the completion. Keeping the tool under constant top load via an adequate feed rate will help reduce the chatter. Getting your Dremel and mimicking the top surface of the Iscar GTN series of cut off insert will cause the chip to form into the groove and actually narrow the chip. Again, I admire your will to finish the job. It is a combination of numerous good practices, and may start a new breed.

I'm really liking your videos. Very good information. I'm wondering what mill you are using, and what collet system is holding your endmill? It looks very quick to change out your tooling. Are they just R8 collets?

That’s good thinking and good work, well done and thanks for sharing Mark.

I have a CVA 1A lathe (1960), it has the best cut off attachment point ever. the cross slide has a dovetail on top at the back so you can run a second toolpost or in my case I run a 1/8th inch Armstrong parting tool on it upside down permanently. It's the most rigid set up I've ever used on a lathe of this size. I have 50 years experience as a machinist/engineer and taught shop in a major UK university for 15 of those years.

tks for posting. Very impressive, so I built one very similar but without welding. works ok so far but needs fine tuning. eg. height needs to be spot on. tool sharpness is important. and maybe I’ll put in a screw to limit spring travel.

With my welding knowledge I’ll tell ya that you should have “V’d” out were the weld was going it would have countersunk the weld giving you more penetration area and less interference for the mounting

Learn something new every day. Interesting cut off tool holder. Regarding the welding, consider putting a generous chamfer on the square stock prior to welding. It will create a v-groove where the square stock lays up against the main body of the tool holder. Then you can weld into the v-groove and not worry about cutting off your weld later to provide good fit to the holder.

Good work and a very interesting tool design. I notice your accent, sounds like home to me. Maryland or Pennsylvania, maybe Virginia. I bought another lathe a few weeks ago and have been accumulating some of the odds and ends I "need" for my small hobby type jobs. Already I miss my old, much bigger and more powerful lathe. Such is life. Thanks for the video, you made everything very clear so that anyone could replicate that tool holder.

I will add my two bobs worth and what works for me---if possible run your lathe in reverse with the tool upside down-- absolutely square to your work with plenty of oil...Have not had a crash in 3 years..I was getting plenty before and gave up parting..Some lathes do not reverse and have a screw on chuck..Bad luck...It will not work for you...E

Wow, that's was impressive, it looks like I need to clone your cut-off tool, I've made many attempts to do cutoffs, I've purchased several types of tools looking for that magic tool, and have yet made a satisfactory cutoff on my lathe a 1935 Leblond 12" round top that I restored in 2018. This fall I took the headstock down, crossfeed, and apron complete down looking for something I missed in the restoration and have not found a smoking gun but, I made some minor improvements. It's back together now but I have had the heart to attempt a cutoff, my excuse is all the cutoff tools I have been wrecked. I do believe I will make your Armstrong tool first and then try it! Thanks, Wink!

Why reinvent the parting tool holder? The new carbide insert style are kick ass. And those old High Speed steel blades blow up if too hard or hot. I am an old timer still working 40 hours a week. You are back to civil war technology!

I would suggest milling a groove for the height knob clearance, I am guessing 20 to 60 thousandths should work for you. Good luck. Lee

Hello Sir, really interesting concept. I have a very small mini lathe, and i am really have problems doing parting, and i would like to try to make this blade holder, but maybe a bit smaller for my little late. Would you, by any chance have made a drawing with dimensions of the tool, as guideline for such a blade holder?

I would be apprehensive that you sacrificed side roll (twist in the cutoff blade) for vertical support. I have no way to predict results. Deep cutoff deflection in any direction scares the heck out of me. At the moment of separation, I have witnessed some catastrophic events. I guess prayer couldn't hurt.

very clever idea. I was (am) going to make a rear toolpost but this design has me confused. Have to find the Tom Lipton video and watch this also. Cant weld so will have to think of some other method of mounting it

I turn my cutoff blade upside down and run my lathe in reverse. The blade can not grab, it will push away from the work piece. Once I learned this method never had a problem with material or speeds.

You could have undercut the place where you were welding. Just had to grind some relief for the weld to go into, then machine it off and lots of holding power. If you MIG weld, you should maybe get your angle right by holding the handle at an nicer angle.

Parting is always a nightmare for me. Generally the blade grabs, and either the workpiece tries to climb over the toolpost, or it grabs, and the workpiece will spin in the chuck. While I've always attributed it the lack of rigidity on my smaller 13x40 lathe, your tool build has me thinking otherwise...........especially seeing how your small lathe handled it. Very cool!

Not sure if this would help for chuck clearance If you drilled from underneath on the leading piece and put some screws in there to hold the cutoff tool, That would eliminate the clamping piece on the side, Also one could have made the whole thing out of one piece and machined the holder as part of the unit itself, and used a slotting tool to cut between the front piece and cut the vertical for the spring clearance, could have been done with and end mill. But looks like I may be building one too

Make and publish the blueprint and we will call it the winky cut off tool holder. And for mini lathes we'll call it winky dinky tool holder.

weld seams always try to close up on you. the direction you welded made the back plate press against the flex mechanism. chimming with a box cutting blade to guarantee clearance is what i do in situations like that.

Great job. I like that!

I know this is a older video but you should have chamfered the square stock to give better penetration and room for the weld .

Funny I had one of those at work in a drawer laying amongst miscellaneous lathe tooling and never used it,looks like I should have.

Do you have details on how the Armstong bolt/holder mechanism works?

Nici work! Do you use the air for just blowing off the chips or does it help cooling the mill also?

You could have drilled and tapped screwing the two parts together.

cool project. Tom Lipton showed an Armstrong cutoff being used and pushing it till it flexes. Did what it was designed to do.

Been a while, but recall Tom Lipton doing a video on this flexure type of holder. Don't recall results and his thoughts.

Have to dig through my "stuff" Seems I may have one of the Armstrong holders.

I don’t get it why oil at the oils not going on the tool of the oils on the surface of what you’re turning the tool is underneath the surface so that means no oil ideally is hitting the edge of the tool

Antonio seria posivel passar as medidas esp. x comp. x largura ,gostaria de faser para meu torninho achei muito bom grato .

Hey Winky, please wink off my you tube screen. tks Brian

Holy cow! That turned out great. I'm inspired to build my own after seeing your results.

Now where do we get some of those dimensions. So we can make our own Armstrong holder?

good job...cause partin is a job that makes ya cringe

I've seen the Armstrong style cutoff tool with the flexion in it before but never used one. That turned out to be a very effective tool, I may have to try one of those at some point if I can't get my parting issues figured out on my import lathe, lol!

Great video. Have completed any drawings yet?

Hello Is that a 000 or 111 size toolpost? Whats the swing on your lathe?

Winky, the original clamping bolt head underside was tapered. As you tightened the nut it pulled the bolt head inwards clamping the blade tight back against the holder, it also forced the blade down tight against the base of the holder. Regards from Australia.

Great cut off tool build there mr. Winky. Thanks for the video.

Great Job Im Amaised! Winky

Excellent video... subbed.. nice idea on the band saw

LA PARTE DE LA SOLDADURA NO TE HA QUEDADO MUY EJEMPLAR UNOS TORNILLOS CIEGOS CREO Q MEJOR

Mark, that was awesome. I'm gonna have to make one as I'm working on a cutoff tool shootout video that compares various cutoff tools and holding setups. Gilles ;)

Always fascinated with your work and I appreciate your modesty. Please let me help with the welding part, as welding is a "magic glue" and from a good stretch of time it has become oxygen in any form of constructions, and hobby's, always improving as we speaking. It is good you use the MIG process, as it gets away welding big chunk of Mild Steel, (once past 12mm, combined thickness, or single) even without preheating, to at least 60/80 degrees "C", before welding, fallowed by slow cooling (in some application in still air ok as long it`s not 5 degrees "C" ambient ...So this part is Ok as long welding with MIG, or a similar Low hydrogen stick rod, but it becomes complicated and inappropriate with stick, (not easy). The other observation is of a similar importance of welding deposition and then removing the welding all together, not the best process. A preparation of one of the parts to be welded, ( some times both), is the best way to go by creating space for the weld to take place, by remove some metal initially, or forming a "V", by removing a corner of the square bar (in this case), or two corners subject to be welded, so after machining the weld away, there would be left a perfect square corner for clearance without interference, or better still as you know better then myself, even a nice concave radius into the weld, in other to minimise a stress point increasing with vibrations and forces applied from the cut. (by the way, normal "MIG" process welding depositions is not hard weld, but actually soft compare to other processes, and also "tough", (resisting impacts, and easy machining). To facilitate the welding arc on starting, cut the welding wire as short as possible to the nozzle and in an angle to reduce the diameter, ( easy burning) and with a gentle strike, not hammering the wire, and please make sure to fill the end welding without leaving a crater, subjected to initiate almost right away a crack do to the rapid cooling and not enough metal solidifying rapidly. in that particular welding in the video it required more Volts then Amps as I noticed a convex weld counter, (apart there is poor bond, the contour creates two notch stresses point, " top and bottom" when instead a "concave" weld by using more Volts would be ideal. Please forgive my poor English... I tray. My Machining ability is worse than your welding so I hope we are learning from one another. I am a retired Boilermaker/ Welder, and that is way I talk the way I do . Hope I interfered in a Positive way, and with respect. I thank you again for your videos and fantastic work..... Cosimo.

I got one of these when I bought an old Colchester Student. Originally I left it in the bin of parts ect that came with the lathe. I knew it was a parting tool holder, but I had carbide insert part off tools so I assumed it was redundant. After snapping so many inserts and breaking a holder I was getting frustrated and assumed the lathe was too old and worn out to do parting properly. After seeing this video and recognising the tool, I immediately tested it (HSS BLADE) and wow!! It just works beautifully! No grabs, smooth cut, even power feed! Medium lathe speed, slow cross slide feed, it just works so well. I have learnt not to assume now. Thank you very much for your content!

I just made a swan neck parting off tool from a piece of carbide tipped circular saw blade, much easier to make and it worked quite well.

22 minutes? Could this not have been shortened?

That is surprising. I have a cheap ($40) Carbide tool that has a weird looking mount. I wonder it is using this idea. Gotta check that. It will chatter, but not easily, so I have no need to replace it, but this looks like a fun thing to build just for learning.

Amazed this works- looks like a recipe for chatter. Guess the thickness of the steel used reduces the movement- and that might match the mount flexing, giving a neutral overall movement. Fortuitous.

Probably a solution for basic stability issues but nevertheless a very interesting concept, surprised it works so well. Did you see the latest video by Rob Renzetti about boring the jaws? I agree with Rob that jaw bellmouthing may well be the most overlooked issue ever. Using a collet chuck whenever possible is obviously the best solution.

Could have ground the corners off of that square stock and then filled it with weld making the weld below the surface I think.

It appears to me that your wire feed rate on the MIG is high.

Great video, thanks for sharing.

I am impressed as well!!!. Too bad we aren't neighbors, I could easily teach you to weld since that was my primary profession for 40 years. I was a welding instructor. You could fine turn my machining. Great video down to earth and not complicated at all. Thanks so much.

I think the result is the cutter shifting down the center line during processing, lead to bad cutting angle meaning damaging cutter and object. Generally thanks for your nice work. Good luck

Great job, Mark. I'll just comment a few things, as a certified welder in MIG and TIG. That weld will almost certainly crack and break under heavy stress. Your welder does not have enough power to penetrate as deep as you're going to want for a tool like this. And then you milled off 90% of the weld bond. My recommendations are 1) you need to clamp your work down - maybe it's time to build a proper welding table? 2) When you need clearance, bevel the areas needing welded, so if you have to mill off anything, you're milling off excess - in this case, had you beveled the corners of the square stock that were sitting next to the blade holder, your weld could penetrate into that bevel. And lastly, 3) I would recommend getting rid of your current welding machine and invest in a decent synergic inverter MIG welder - something like the Primeweld MIG 180 or even the Titanium MIG 170 (Harbor Freight). You'll be amazed at how much a better welder you will become using a machine with better technology. Looking forward to your next project!

Finally I understand why that was designed like that. I never heard an explanation. You did a nice job making that.

I designed an upside down cut off holder. Works great. All problems went away. Never go back to original way!

Very good video, sure was ver good, u r very creative did a very good job with all of the building, I would like to build one. I haven’t finished the other one u made first one u showed. Very good job

I am impressed to. and I like it too!

Wow! Glad I watched this. Now I have to build one for my 9" Southbend. I like some of the suggestions below for attaching the 1/2" bar for the tool post; especially milling a shallow channel on the tool post side to set the bar in. Two flathead screws to fasten the bar to the tool holder and your golden. Looks like you made your holder out of cold rolled. Anyhow, you did an excellent job making this.

I'm surprised it worked so well because of the thickness of the plate you used I'd have used 1/4" or 3/8" not 1/2" BUT it worked fantastic ! I tried a cutoff yesterday with my cheapo chinese cut off tool with a carbide insert in it .... you guessed it it grabbed and bent the bottom part and busted the insert... i said fooie on it and cut it with the HF band saw ! which works a treat now that I have your plate in it ! thank you.

That thick plate might be too thick on your lathe cut off tool. Also y get more clearanse for your thumb wheel if you just mill half of it off. It might not do it's job if it is too rigid.

Nice video, I had not seen this style holder before. Retired welder here trying to learn machining. On the welding, you could have beveled the corners you welded then when removing the excess weld you would have retained more strength. Thanks for the videos, very helpful and informative.

To get a good weld on anything heavy preheat

Nice work. You also could drill and tap and counter bore two screw on the weld side into your tool holder for additional holding power. To take some pressure off of the weld. Also the .500 x .625 is a great idea. I really like the holder. I think I'll make one myself. Great content. Thank you, EM.

EL UTIL EN GENERAL MUY BIEN SALVO LA SOLDADURA

IS A SKETCH OR PRINT AVAILABLE ??

Dear Winky. Thanks a lot for this video! Cutting off always was russian roulette to me and I never got my head around the reasons. Now it's pretty clear thanks to you! Concerning the vibes on your second attempt: Well, it's about vibes - every single item in this world has got its inherent resonant frequency (frequencies to be correct) depending on the mass, ridgidity and geometrie. Change one part of the equation just a little and it changes everything. A dedicated engineer might be able to solve the equation for not hitting on for speciffic revs and diameter but it might be easier and quicker just to try out. The importent thing is, that the edge wont tend to jam anymore with this holder! You really made my day!

Nice work , I guess I need to build one too

i like it, i have had many mishaps parting, broken parts, broken tools, i like the look of this, a project may be on the cards

The tool holder needs the back piece you cut off because when the cutting blade flexes it is supposed to push against the top of the grove the blade sits in but without it the blade can pivot way to much

That style of cut off tool is very common here (in Finland) on older manual lathes. Most I have used have been like that. Not sure what brand or where they were made but most of the old lathes I have used were made in the eastern Europe (Soviet Union, Poland, Czechoslovakia etc, so I suppose the tooling was of the same origin.

I always enjoy your videos and your unique means to achieve a turning or cutting. I use the FOR by Eccentric Engineering which also uses the T shaped blade. While it is designed to be used in the QCTP it is designed to be used with the Lathe running in reverse so the chips fall out of the workpiece thus keeping the workforce clear of the removed chips thus minimizing the clogging and some of the risks to the tool digging in.