Making New Drawbars for the ZX7045 Milling Machine

In this video we make two new imperial drawbars for my mill, including some screw cutting (the right way and the wrong way)!
Channel artwork: Ryan Toomey

[@hogan6216]

Nice job...Tools are the coolest...

[@swanvalleymachineshop]

Ha Ha been there , done that . Doing a rush job for my self off camera . My mind was completely elsewhere at the time but picked up on it in time & saved the part !!! I am sure everybody has done it at some stage ! Great result 👍

[@jonsworkshop]

Hi Max, lol, the annoying thing is, I have been caught out by this before as well, damn memory!! Cheers, Jon

[@jaybailey3518]

Your honesty makes you a "Saint" !!! We've all done it...

[@jonsworkshop]

Lol, thanks Jay

[@MachiningandMicrowaves]

I was yelling at the screen about that compound angle! These days I use carbide full-form threading inserts and plunge straight in with the lathe in reverse and a rear toolpost, must be five years since I used the compound for threading. There's something very satisfactory about the proportions of a nicely made shouldered nut.

[@jonsworkshop]

Hi Machining and Microwaves, thanks for the comment. There certainly is, I thoroughly enjoyed re-learning 😊

[@jimb1783]

Well done Jon Leaving in the mistakes helps everyone learn. I was one of those shouting the angle was wrong!

[@jonsworkshop]

Hi Jim, thanks for the comment. Lol, I knew there would be a few shouting🤣🤣

[@Warped65er]

Nice recovery. Thx for the vid.

[@phildunne2632]

I can't tell you how pleased you posting the mistake and leaving it in the video I am. Let me explain Im just a hobby home gamer so rely on KZbin videos like yours for information. For a few weeks now ive been trying unsuccessfully to single point cut a non standard 3/4" 8 tpi bsw thread and thats exactly what I've been doing wrong! The first 3 or 4 passes seem ok then it either breaks the tip or just starts basically ripping a thread! Thank you! Thank you! Thank you!

[@jonsworkshop]

Hi Phil, thanks for the comment. If I ever make a mistake, I will always show it, best way of teaching!! If you check out 'That lazy Machinist' (think that's right), he has done a very good explanation video from memory on why this happens, it's always good to understand the reasons behind something you have experienced. Cheers, Jon

[@allenhunt3070]

Nice job Jon. I always enjoy your explications.

[@jonsworkshop]

Thanks Allen, much appreciated. Cheers, Jon

[@richardmills5450]

Your building a nice little channel matey. Some very interesting stuff. Cheers

[@MattysWorkshop]

Gday Jon, I was looking at the compound and thinking it don’t look right but sadly you couldn’t here me trying to say something, I try to single point all my external threads, I find it enjoyable, I used to put a thread relief but now I just draw the tool out at the end and this saves another process, great job mate, cheers

[@jonsworkshop]

Hi Matty, thanks for the comment. Yep, I used to be fairly proficient at not using an undercut. Clearly my confidence has not faded as quickly as my memory 🤣🤣🤣🤣

[@daveticehurst4191]

Another job ticked off the To Do List. Great outcome. Regards from Australia.

[@jonsworkshop]

Hi Dave, thanks for the comment. It certainly will be nice to be able to use the boring head when I need it now! Cheers, Jon

[@MrFactotum]

Nice one Jon, now youv'e knocked the rustiness off you can thread for England or is that Scotland!!!! well done ATB Kev

[@jonsworkshop]

Hi Kev, yup, need to be having another go before 25 years goes by again 🤣🤣🤣🤣. Cheers, Jon

[@TrPrecisionMachining]

very good job jon

[@jonsworkshop]

Hi Tr, thanks for the comment, much appreciated. Cheers, Jon

[@RB-yq7qv]

Very nice job Joh. I would colour code them to ensure no mistakes. One always has a time when rushing can lead to the wrong one selected. Have a great week

[@jonsworkshop]

Thanks RB, I will definitely be marking them up. Cheers, Jon

[@bostedtap8399]

Good idea, maybe a colour mimic plate on the head motor?

[@eyuptony]

Nice work Jon, they'll look well hung on the wall behind the mill. It's a reality that what you once took for granted, if you don't practice it often, you'll forget it. But it comes back afterwards, as you've just demonstrated. Cheers Tony

[@jonsworkshop]

Hi Tony, thanks for the comment. Lol, these days I struggle to remember what I had for breakfast!!

[@robertburns2415]

Nicely done

[@markhollinshead4153]

Great video Jon, that boring head looks like a cracking bit of kit

[@jonsworkshop]

Hi Mark, thanks for the comment, it certainly is, can't wait to play with it. Cheers, Jon

[@andrewdolinskiatcarpathian]

Morning Jon. Thank you for giving me the inspiration I need to attempt single point screw cutting on my own lathe. Your two new drawbars came out perfectly. Well done. 👏👏👍😀

[@jonsworkshop]

Hi Andrew, thanks for the comment. Yup, I am very pleased with them. Go for it!! Cheers, Jon

[@carlwilson1772]

Great work Jon, they look superb and work superbly. I've made that same mistake with the angle when single pointing lots of times. I have just got hold of some very large high tensile steel bolts that were going to be scrapped. One of them is going to eventually become a drawbar for my Harrison Mill vertical head. Thanks again for a great film.

[@jonsworkshop]

Hi Carl, thanks for the comment. In my next video (assuming my idea is a success) I will have the tool to make sure that never happens again...... hopefully 🤣🤣

[@carlwilson1772]

@@jonsworkshop Sounds great I shall look forward to it.

[@graemebrumfitt6668]

@@jonsworkshop “The best laid schemes o' mice an' men" 🤔GB:)

[@Man-in-da-shed]

I must be the only one who didn’t see anything wrong, very educational Jon.

[@jonsworkshop]

Hi Eun, thanks for the comment and feedback, much appreciated mate. Cheers, Jon

[@Steviegtr52]

Nice work opn the drawbars Jon. Screwcutting is something I have never done. One day I must have a go. Regards. Steve.

[@jonsworkshop]

Hi Steve, thanks for the comment and feedback. Go for it!! Cheers, Jon

[@stevechambers9166]

Liked the way you made them nuts I would of forgot to add on the width of the parting off tool lol thanks for your time Jon

[@jonsworkshop]

Hi Steve, thanks for the comment, lol, I very nearly did. Cheers, Jon

[@homemadetools]

Good work. We shared this video on our homemade tools forum this week 😎

[@jonsworkshop]

Awesome! Thank you!

[@tonypewton5821]

Hi Jon, another excellent video! I enjoyed it! 👍 Regards Tony

[@jonsworkshop]

Thanks Tony, much appreciated mate. Cheers, Jon

[@graedonmunro1793]

G'day Jon ,, good to see threading with HSS instead of a insert.👍

[@jonsworkshop]

Hi Graedon, thanks for the comment. Yup, HSS is not to be sniffed at, carbide works but to get a good finish, you need to be travelling at underpants threatening speeds.

[@hersch_tool]

Nice job! And that's a very nice lathe!

[@jonsworkshop]

Thanks, much appreciated, Cheers, Jon

[@Machine_NZ]

Hi Jon, nice job on the draw bars. I'm sure it won't be 25 years before the next go. Regards Kevin

[@jonsworkshop]

Hi Kevin, thanks for the comment. Lol, I hope not based on this demonstration 🤣🤣🤣🤣

[@bernardreilly7519]

Hi Jon the first time I used the half angle method for screw cutting I made the same mistake as you easy done. Bernard Glasgow.

[@jonsworkshop]

Hi Bernard, thanks for the comment. Lol, I too have been bitten by this previously......... another memory failure 🤣🤣

[@jaygee9249]

Hi John, I've always just plunged straight in, no compound angle, even at tech college that how we cut the thread, been doing it for years. Both acme and vee, although ran spindle slower and found reversing lathe was the best way. Less cursing! Anyway there always more than one way to skin a cat

[@jonsworkshop]

Hi, me too really unless doing really coarse big threads. It is useful info though for those with micro lathes as they really aren't man enough to straight plunge so I thought I would show it. Cheers, Jon

[@howder1951]

Nice work Jon and a very well made video, I enjoyed the whole thing. I spotted the angle right away because I have a similar problem on my lathe. The way the compound protracter reads I have to set near 60 degrees. Cheersmate!!

[@jonsworkshop]

Hi Howder1951, thanks for the comment and feedback. Wait till tomorrow's video, I think I have just come up with a solution for you 😉

[@joell439]

Success

[@andybleasdale7045]

Good work Jon - agree that separate draw bars was the way to go. Perhaps mark one so you know which one is UNC and which one is BSW. great work again Andy

[@jonsworkshop]

Thanks Andy, I will definitely be marking them up as I have just proven how good my memory is🤣🤣

[@nobbysworkshop]

Nice job on the draw bars Jon, and a good recovery on the threading. I did notice the angle on the compound, but as I've never done any single point, I wasn't absolutely sure. Anyway, all's well that ends well. Cheers Nobby

[@jonsworkshop]

Hi Nobby, thanks for the comment and feedback, much appreciated. Cheers, Jon

[@joerogi8401]

Could you explain how you don't have to invert the mill to install the upside-down boring head draw bar ? John 🇨🇦

[@jonsworkshop]

Hi John, lol, I had to read this 3 times before I got it🤣🤣🤣🤣🤣. It's been a long day! Cheers, Jon

[@matspatpc]

Nice little project. Works differently to the drawbar for my mill - which is just a very long bolt with a hex end [I made a replacement by whittling down a 19mm hex-bar, since the one that came with mine only fits the one arbor that came with my mill - Clarkson one - and all the tooling I've bought is M10, not 3/8" Whitworth]. I too spotted the 30 degrees in the wrong axis. Largely because I made the same exact mistake. I've since learned that some lathes have the angle scale relative to X, some relative to Y. So, on some lathes, you'd be setting it to 30 degrees (or 27 or whatever), and others you set it to 90-. And I've also learned that it's only required for quite coarse threads. There's no need to do that for threads up to around 3mm pitch (unless the material is very tough).

[@ThePottingShedWorkshop]

Oh dear, I spotted the compound at the wrong angle and could tell what was coming😟. I have an M300 too except mine is a 4tpi leadscrew. I do quite a bit of single point threading, so a couple of things I did to improve life: 1. Get a decent piece of HSS, pref UK made, it chips far less on the tip. 2. Make sure the tip has the sharp point stoned to a radius. For a biggish thread it can be quite rounded and I have different bits for much finer threads. A runout groove at the end of the threads would help too. I never stop the motor to terminate the threads, I've set the rampdown rime to 2.5s so its too imprecise. I use the technique of opening the halfnuts, stop the motor, pull the tool out, reverse the lathe and reengage on the same number. As long as your threading dial doesn't do a complete revolution the leadscrew and thread will still be correctly synced up.

[@jonsworkshop]

Hi Robert, thanks for the comment and feedback. Lol, I was trying to be smart not using an undercut, I used to be able to do it no problem at all but it is clear that the mists of time degrade your skills much quicker than your confidence 🤣🤣🤣🤣

[@retromechanicalengineer]

Great video Jon. My drawbar is fairly poor, I could do with making a couple myself. Best wishes, Dean.

[@jonsworkshop]

Hi Dean, thanks for the comment. Yep, my as supplied one is pretty poor quality, night and day to the new ones. Cheers, Jon

[@Rustinox]

Almost every time we think it's an easy little job, we screw up. Because of not enough thinking... Good thing you could recover it.

[@jonsworkshop]

Hi Rusti, thanks for the comment. You are so right!! Cheers, Jon

[@Workshopfriend]

Last night I was also making a draw bar for my mill - with an M16 thread. Also like you I knocked the tip off my 60 Deg tool. I realised that stopping the lathe on a cut was the problem. After I reverted to my normal practice of cutting a groove for the tool to run into there was no problem. I wonder if that was part of your problem?

[@jonsworkshop]

Hi, yes, it definitely was. When I used to do this stuff regularly, my hand eye coordination was good enough to be successful. Clearly my confidence hasn't faded as quickly as my skills lol

[@graemebrumfitt6668]

Rite Jon, That was a great comeback, if I didn't know betterer I'd say you did it on purpose to show us mere mortals how we can get out of tricky situations, love your nuts, great way of machining. Will the bars n nuts get a blueing or left as is? Stay safe n well Dude. TFS, GB :)

[@jonsworkshop]

Hi Graeme, thanks for the comment, if only I was that good lol. No blueing on these, just left as is I think, we all get rusty nuts eventually 🙄

[@samuelfielder]

When single point threading without an undercut, were you using the M300's foot brake to stop at the end of each pass? It didn't sound like it, but the chuck did stop very quickly. Keith Rucker can single point thread on his Monarch without an undercut, but to me it seems extremely perilous. You only need to overrun by a small angle, on just one pass, and tool will surely dig in. How did you manage it in the old days before you forgot how to do it?

[@jonsworkshop]

Hi Samuel, yes, foot brake was being used but it is sketchy. In the old days when my hand eye coordination was much sharper, I just used to retract the cross slide, once you are well practiced at it, it's pretty robust....... the key word there is practice! Many mistakes are made during the practice period lol. Cheers, Jon

[@howardosborne8647]

It took you long enough to spot the angle of the compound was set from the wrong zero index🤣 Couldn't you hear us all shouting 'don't do it!' Also good to see you cut a runout gutter/undercut on the second attempt

[@jonsworkshop]

Hi Howard, lol, I should have been listening harder!! Lesson learnt (again) 😉 Cheers, Jon

[@davemason6273]

Cracking job Jon. I tend to set the thread depth I want first using both the cross slide and compound slide. Note both slide positions, wind out the compound, and making sure to return the cross slide to the marked position before each pass, just wind in the compound a bit each pass until you get to its set position. Many ways I know, but this works for me. PS; Is the revolving centre with the red ring on a special, or home brew? I like the clearance you've got to the work for threading.

[@jonsworkshop]

Hi Dave, that will work! The revolving centre is a Vertex one, very good quality and has a selection of differing geometry points that fit in the front on a taper, well worth getting one. Cheers, Jon

[@davemason6273]

@@jonsworkshop Set on order, thanks Jon.

[@davemason6273]

@@jonsworkshopHi Jon, just received my Vertex live centre :-) £190 well spent. Thanks again

[@dermotkelly2971]

Good job John. screw-cutting is something you have to be doing at least once a month in my opinion.

[@jonsworkshop]

Hi, thanks for the comment. Definitely, not every 25 years lol. Cheers, Jon

[@russelldold4827]

Hi Jon, at 19:15 you're milling the hexes for the nuts. I'm curious about your orientation of the hex collet block in the vice, effectively gripping across the edge rather than across flats as I'd have expected. Any reason for that?

[@jonsworkshop]

Hi Russell, thanks for the comment. Good question. My collet blocks are cheap import ones, when they arrived I did some checks on the surface table, the relationship between the flats and the collet taper were way better than between the flat transitions and the collet taper. For jobs like this when repeatability on depth is needed all round the unit, I always locate on the 'best bit' and clamp on the 'crap bit'. Hope that makes sense. Cheers, Jon

[@russelldold4827]

@@jonsworkshop Thanks, Jon. That makes perfect sense.

[@TERRYB0688]

Nice one Jon, see you used you “get out of jail free card” have only ever done single point once and that was purely to prove to myself I could do it, the Colchester can’t go in reverse so have to use the thread dial indicator although I now have the original 3hp three phase motor so with the help of a VFD I will be able to reverse the lathe, nice one Jon 🇺🇦🤗👴🏻👍

[@jonsworkshop]

Hi Terry, thanks for the comment. Got lucky with this one😊. Spotted your email, will respond soon mate. Cheers, Jon

[@624Dudley]

Ahoy Jon, that was some nice work 👍. Pardon the following ignorance: is the captive nut used with a second wrench (in lieu of a spindle brake) to prevent rotation while tightening/loosening the flange nut? 🤔 I ask because my spare mill, a seldom used Rong Fu 31, has no spindle brake. A drawbar like yours could be quite an aid.

[@jonsworkshop]

Hi Dudley, thanks for the comment. In short, no. It will be no good for that unfortunately. I just whack my gears into lowest speed and tighten up against the torque generated by the low gear range. Bit cowboy, but doesn't really do any harm. Cheers, Jon

[@thehobbymachinistnz]

Good work Jon. When you were talking about the dial indicator which you setup for measuring thread depth, I immediately noticed that the compound slide looked like it was around 30 degrees off the line of the spindle, instead of 30 degrees of the line of the cross slide travel. I have seen lathes that have the degree stamps measured from the spindle axis, and also some measured from the cross slide axis. So in some cases (e.g. when the marking are measured from the spindle axis) you can set the compound slide to say 29 degrees believing that this is correct, but that is the wrong angle (my Emco is like that). For my Emco lathe, I need to set the compound slide to say 59 degrees, which is 29.5 degrees off the line of travel of the cross slide. Also, I saw that you did not have a relief cut for the end of the threading tool to go in to. I guess that is what caused the tool to chip when the tool did not stop in time for the end of the thread. All in all good video and I'm sure your mistakes and corrections will help those people who are new to single point threading on a lathe.

[@jonsworkshop]

Hi Jon, thanks for the comment and feedback. I was trying to be smart not using an undercut, lol I used to be able to do it like that without any issues, it is clear that the mists of time degrade your skills much quicker than your confidence 🤣🤣

[@adamdebicki9237]

Hi Jon. How do you find availability of threaded cutters for the Clarkson. Seems like people are moving away from these. I have a posilock that I inherited but not sure whether to source threaded tooling or go with ER collets.

[@jonsworkshop]

Hi Adam, I would always advise ER as these hold any shank type. Keep your eyes on Ebay for 2nd hand job lots of the threaded type, there are bargains to be had occasionally. Having both options at your disposal is useful. Cheers, Jon

[@brucematthews6417]

I was yelling at my screen but I guess the connection wasn't good enough for you to hear me in the past.... 😁 I nodded when the screen came up with "did you hear the penny drop". I've done the same thing myself. It's easy enough when we're trying to keep all the little details in mind all at the same time.

[@jonsworkshop]

Hi Bruce, thanks for the comment. Lol, I knew there would be a few who would be shouting at the screen 🤣🤣🤣🤣

[@PaulSteMarie]

Measuring the infeed is a bit risky, especially with a hand-ground tool. The problem is the depth directly depends on how sharp the tip is. Tools for external UN/ISO threads ideally have a flat at the end that is 1/4 of the pitch, so about 0.020 for a 12 TPI. However, threads are often cut with a close-to-perfectly pointed tool. That translates to about 0.035" variation on the pitch diameter for the same infeed.

[@garyhunt9838]

Hey there Jon ☺ new subscriber here , really enjoying the video's 😀 What i was wanting to ask you or any of the viewer's that might know. I am new to using a lathe , i managed to get my hands on a cheapish one , nothing special. The issue with it is that the crosslide leadscrew is bent , which make's it not very nice to use when making facing cut's and feeding in. So what i am wanting to know is . . What type of steel would be the best to machine a new one from ?

[@jonsworkshop]

Hi Gary, welcome to the channel, I hope you find the content interesting and Informative. I would use EN8 (high tensile, but free enough machining). Depending where you are located, you may need to look for the equivalent grade etc. Hope this helps. Cheers, Jon

[@garyhunt9838]

@@jonsworkshop Hi Jon. Thank's ever so much for the reply. Yep i am finding your video's very entertaining and educational 😀 Ok EN8 yeah ? I am in the U.K mate , so il have a look around for some of that then. Cheer's buddy 👍

[@iancoates1799]

You didn't mention when you changed over, if you reground the tool for the whitworth thread at 55 degrees or 60 and reset the compound.

[@jonsworkshop]

Hi Ian 55 deg as Whitworth form, the compound slide angle was the issue, it was set to 27.5 deg away from the saddle slide, but should have been set from the cross slide. Cheers, Jon

[@wjb2]

Hi Jon He who has not errored , never learns. it’s to easy to edit out cock ups in this modern world when showing how to do stuff quo dos for keeping it in.

[@jonsworkshop]

Hi Bill, thanks for the comment. I will always show the cock ups mate, there is more learning to be had in that than just seeing stuff get made perfectly each time. Cheers, Jon

[@improviseddiy]

Threading takes practice. You should do it more often. 🤣Interesting how many different imperial thread types exist. 🤔

[@jonsworkshop]

That's true!, thanks for the comment.

[@BedsitBob]

As soon as I saw the setup, I knew the compound was set incorrectly.

[@jonsworkshop]

Hi Bob, lol, I knew there would be a few who would😁

[@chrisstephens6673]

And if you had just gone in straight you wouldn't have ...., no i wont rub it in!😂

[@jonsworkshop]

Hi Chris, they were my exact words to myself (well mixed in with some less broadcastable ones)! Learning is fun. Cheers, Jon

[@Masonfox8272]

Hey there Jon’s workshop do you have any stickers you can send me if so what’s your email