I did quite a few things wrong in this video as the comments have pointed out. I’ve been using the tool without problems for a while now and it is way better than the older blade type tools. However, for successful parting off you should: - minimise tool overhang - part off as close to the chuck as possible - keep spindle speed fairly slow - use plenty of cutting fluid
This has a lot of views, I hope folks read the comments rather than buying a blade parting tool and emulating this method. Parting is about rigidity and then more rigidity. I would never contemplate using a blade parting tool in a small lathe, in my case it would hang out from the turret too far, just as in this case it hangs out from the tool post. A single piece parting tool is much better for a small lathe. These tend to have a fixed maximum diameter and work really well. I can part up to 41mm diameter and I accept that, as my limit for parting. Larger than that, I tackle the job some other way. The rigidity of this set up is compromised by the QC tool holder, the blade holder holding the blade away from the tool post (would be much improved by single piece tool) and then the blade sticking out more than is required. So many comments about the speed being too fast, I part at the same speed as I turn on my cnc lathes, they have a 4" chuck so not large. This is shown on my channel for anyone who has difficulty with that statement. When parting, get as close to the chuck as possible, 3mm is ample space, or should be. I often part off further out when making multiple washers in a single set up, but my machine seems to handle it OK.
Lower the speed and push the parting tool in so there’s less over hang and make sure it’s 90 degrees to to the lathe bed by pushing it against the chuck face then tighten the tool post.
Hi, I have a super seven and the same style Q/C tool post, as seen in your vid the tool can dig in when parting. I made a rigid rear tool post and have had no problems since, I strongly suggest you make one. In the last couple of years I've been using an insert parting blade, would never go back to HSS. As already mentioned, slow the speed down and flood the cut with lube, preferably suds as it will take the heat away better than straight oil. The heat causes tool expansion in the slot which will cause problems. Colin
I bought a tool like that for my Chinese lathe. I made a solid rear parting tool holder and it transformed the parting performance as it's exceptionally rigid and eliminated the snatching and flexing. Although you can mount the tool upside down to keep the same spindle direction , I didn't and i have to part off with reverse spindle direction but it works great. Because it worked so well I gave it a real hammering testing it and it put so much pressure on the insert it bent the seat down causing it to gape and not hold the insert. It would be better to buy the holder with more material under the insert
for a myford I found HSS is best. get an Easylap diamond hone and just sharpen your edge. run the spindle dead slow with lots of oil. Inserted carbide has a blunt edge which helps tool life when ran at proper speeds but it requires regidity. HSS can be honed razor sharp which reduces the cutting forces so its ideal for the myford. For running steel on the myford you want to run at no more than 30m/min. remember this is 1930 technology back when HSS was the cutting tool of choice. Using carbide is a different kettle of fish.
been machining 316 stainless with a 30thou DOC at 110 rpm in backgear at 3.7thou per rev using HSS. No issues with tool life just a few seconds to hone every few cuts.
did you se that?? 4:25 ? the entire QC-holder flexed in the toolpost - a very bad/soft holder,or not locked thight enuff - the post didnt move at all , very lucky to get away whit that one
Try re-watching your video at the 4:25 mark. There was an obvious catch of some kind and you can then see just how much flex there is between the tool holder, tool post and the slide clearances being taken up. As handy and quick to use at those quick change tool posts and holders are there are some downsides to just how much rigidity they have with the tool tip that far from the stud used to lock the tool post down. It's not a fault of the lathe, tool post or even your new cut off tool, it's just a result of the design limitations of a light weight lathe and how a QC tool post works. I didn't notice if your Super 7 had the long or short cross slide on it, but for any smaller lathe in a home shop that does have a T slotted cross slide and especially the Super 7 I'd be seriously considering the George Thomas rear mounted tool post specifically designed to be used on your Myford lathe. Hemingway Kits sell the casting, and the full build article Mr. Thomas wrote for the M.E. magazine is in his book The Model Engineer's Workshop manual. That rear mounted tool post bolts directly to the top surface of the cross slide and has a direct line of support for the cut off tool that results in much better rigidity and better results because of that.
Well spotted! The insert came loose, which I solved by pushing it more firmly onto the holder. I was going to talk about that in the video but (a) I forgot and (b) I thought the video had gone on more than long enough already;-)
@@MetalMachineShop I think if you watch that again in a slower speed, you will see the whole tool post rocking. Untill you solve that problem, you are going to continue to get crappy results. Perhaps an out rigger of sorts could be affixed to afford additional rigidity. Remember the old addage "A rigid tool is a happy tool."
I use a myford rear tool post with dixons style carrier and get good results, the tool cant dig in at the rear. Worth looking into but maybe you have solved the prob by now.
Thank you for the video.. Will you please post a link to where you bought the parting off tool.. especially the holder.. I've been looking for one for a while...
www.arceurotrade.co.uk/Catalogue/Cutting-Tools/Lathe-Turning-Tools-Indexable/ARC-Indexable-Turning-Tools/SLTBN-Part-Off-Blade-Tool-Blocks-with-Part-Off-Blade Pretty sure it was this one! Thanks for the comment!
Other viewers have pointed out some of your parting off errors, but have you considered using a rear mounted toolpost with the parting tool inverted? Due to the mechanics of machinery...well that’s my vague understanding, parting off ‘upside down’ is easier and is less prone to the tool digging in. Quite a few YT videos out there show the set up. You’ll need to buy or make a rear toolpost, though. Use cutting fluid as well...aluminium is nice to cut, but it’s a ‘sticky’ metal with regards to cutting tools. WD40 or paraffin works well on aluminium.
I was was just watching the way you set the part off blade it would have been more easy if tou went to the face of the job then you could see how far the blades standout needed to be
If it's a screwcutting lathe, you need the right gearbox setting and spindle speed plus the right screwcutting tool. Alternatively, you can use a tailstock die holder and either rotate the spindle manually or using a very slow spindle speed if achievable.
I just wanted to comment on all the things you did wrong but i see the other commentors have already covered that for me. So I will have to settle for telling you your work area needs cleaning.
It seems as if it dug in - he can be glad he got away with it. I hope he posts the video when his luck has run out. The video reminds me of my driving. I hav'nt been in an accident recently but it is not because of my driving skills - it's pure luck!
Absolutely right, as they used to say in star trek, you canny break the laws of phisics. and the longer something is the more it will flex. And to again quote, this time the great Renzetti, everything is made of rubber.
ah the absolute POS "Dickson" type quick change tool post, best thing to do with these is chuck them in a scrap bin! go get yourself either a Multifix or a Tripan and keep the tool stick out to a minimum, oh and get a decent lathe too, like a Schaublin 102! :-)
Gee you can be blunt! Unfortunately though you are dead right. A blade in a lathe that size is not a good option. Single piece parting tools are much better. The hangout of the tool in a QC tool post is too large anyway and then to make it worse with a blade just makes no sense. I can't believe how folks try to part off any more than 3mm from the chuck. How does the cost of a Schaublin compare with a Myford?
@@smallcnclathes both decent Myfords and Schaublins fetch very good money here, in fact all machine tools have risen in cost during this pandemic! As for parting off, the Schaublin is more stable as it has less slideways, I’m only talking about the WW style Schaublins, I’m not sure about the screw cutting 102 series with a carriage and apron etc but I think they are more robust than a Myford .
@@crozwayne I did put up a lengthy comment of my own! I was just surprised at you being such a Cross Wayne, that’s all. Parting is aways a pain until one gets it right. Then it becomes just another part of turning. As I say in some of my videos, my parting tools cost me a lot of money, but they never let me down. Hundreds of thousands of parts all parted at the same speed at which they were turned.
Наука
I did quite a few things wrong in this video as the comments have pointed out. I’ve been using the tool without problems for a while now and it is way better than the older blade type tools. However, for successful parting off you should:
- minimise tool overhang
- part off as close to the chuck as possible
- keep spindle speed fairly slow
- use plenty of cutting fluid
read my comment below
Also, keep a constant pressure on the tool to avoid chatter and a bit of ‘juice’ would help too.
This has a lot of views, I hope folks read the comments rather than buying a blade parting tool and emulating this method.
Parting is about rigidity and then more rigidity. I would never contemplate using a blade parting tool in a small lathe, in my case it would hang out from the turret too far, just as in this case it hangs out from the tool post. A single piece parting tool is much better for a small lathe.
These tend to have a fixed maximum diameter and work really well. I can part up to 41mm diameter and I accept that, as my limit for parting. Larger than that, I tackle the job some other way. The rigidity of this set up is compromised by the QC tool holder, the blade holder holding the blade away from the tool post (would be much improved by single piece tool) and then the blade sticking out more than is required. So many comments about the speed being too fast, I part at the same speed as I turn on my cnc lathes, they have a 4" chuck so not large. This is shown on my channel for anyone who has difficulty with that statement.
When parting, get as close to the chuck as possible, 3mm is ample space, or should be. I often part off further out when making multiple washers in a single set up, but my machine seems to handle it OK.
Lower the speed and push the parting tool in so there’s less over hang and make sure it’s 90 degrees to to the lathe bed by pushing it against the chuck face then tighten the tool post.
Hi, I have a super seven and the same style Q/C tool post, as seen in your vid the tool can dig in when parting. I made a rigid rear tool post and have had no problems since, I strongly suggest you make one. In the last couple of years I've been using an insert parting blade, would never go back to HSS.
As already mentioned, slow the speed down and flood the cut with lube, preferably suds as it will take the heat away better than straight oil. The heat causes tool expansion in the slot which will cause problems.
Colin
I do like those types of parting tools, but the inserts for steel and aluminum are usually different.
Thanks for sharing take care.
I bought a tool like that for my Chinese lathe. I made a solid rear parting tool holder and it transformed the parting performance as it's exceptionally rigid and eliminated the snatching and flexing. Although you can mount the tool upside down to keep the same spindle direction , I didn't and i have to part off with reverse spindle direction but it works great. Because it worked so well I gave it a real hammering testing it and it put so much pressure on the insert it bent the seat down causing it to gape and not hold the insert. It would be better to buy the holder with more material under the insert
That dug in at 4.25 you were lucky to get away with it. see the flex! Slow speeds are best for parting.
Yeah the hole tool holder dipped , and also it’s slightly below CH .
I think that your spindle speed is way too fast in both of the tests that you carried out.
Sidecarbod That was my first thought as well.
Very clear and useful video mistakes yes but one of us are perfect keep it up.
Very nice!
Yes, there is so much to learn with lathes.....but you get there eventually.
for a myford I found HSS is best. get an Easylap diamond hone and just sharpen your edge. run the spindle dead slow with lots of oil. Inserted carbide has a blunt edge which helps tool life when ran at proper speeds but it requires regidity. HSS can be honed razor sharp which reduces the cutting forces so its ideal for the myford. For running steel on the myford you want to run at no more than 30m/min. remember this is 1930 technology back when HSS was the cutting tool of choice. Using carbide is a different kettle of fish.
been machining 316 stainless with a 30thou DOC at 110 rpm in backgear at 3.7thou per rev using HSS. No issues with tool life just a few seconds to hone every few cuts.
I thought you said you would use lube on the steel. You really need a continuous drip of something fluid.
thanks for posting
did you se that?? 4:25 ? the entire QC-holder flexed in the toolpost - a very bad/soft holder,or not locked thight enuff - the post didnt move at all , very lucky to get away whit that one
Try re-watching your video at the 4:25 mark. There was an obvious catch of some kind and you can then see just how much flex there is between the tool holder, tool post and the slide clearances being taken up. As handy and quick to use at those quick change tool posts and holders are there are some downsides to just how much rigidity they have with the tool tip that far from the stud used to lock the tool post down. It's not a fault of the lathe, tool post or even your new cut off tool, it's just a result of the design limitations of a light weight lathe and how a QC tool post works. I didn't notice if your Super 7 had the long or short cross slide on it, but for any smaller lathe in a home shop that does have a T slotted cross slide and especially the Super 7 I'd be seriously considering the George Thomas rear mounted tool post specifically designed to be used on your Myford lathe. Hemingway Kits sell the casting, and the full build article Mr. Thomas wrote for the M.E. magazine is in his book The Model Engineer's Workshop manual. That rear mounted tool post bolts directly to the top surface of the cross slide and has a direct line of support for the cut off tool that results in much better rigidity and better results because of that.
Well spotted! The insert came loose, which I solved by pushing it more firmly onto the holder. I was going to talk about that in the video but (a) I forgot and (b) I thought the video had gone on more than long enough already;-)
PS - I have got a G Thomas rear tool post somewhere but I have never used it, thank you for the reminder!
Saw it too 👍
@@MetalMachineShop
I think if you watch that again in a slower speed, you will see the whole tool post rocking. Untill you solve that problem, you are going to continue to get crappy results. Perhaps an out rigger of sorts could be affixed to afford additional rigidity. Remember the old addage "A rigid tool is a happy tool."
@@MrRShoaf and in this case in particular, "A short tool is a happier one as it's not going to be mangled up like a long sticky out one !" lol
I use a myford rear tool post with dixons style carrier and get good results, the tool cant dig in at the rear. Worth looking into but maybe you have solved the prob by now.
It’s been working pretty well in the front tool post but I think it would be even better in a rear toolpost
Yes that was useful. I was smiling to myself as I read the comments. The best was 'Clean up your work area' I mean REALLY??
Hi there. Are you able to tell me if the parting off tips that can be found on Ali Express will fit this parting blade. Thanks
Thank you for the video.. Will you please post a link to where you bought the parting off tool.. especially the holder.. I've been looking for one for a while...
www.arceurotrade.co.uk/Catalogue/Cutting-Tools/Lathe-Turning-Tools-Indexable/ARC-Indexable-Turning-Tools/SLTBN-Part-Off-Blade-Tool-Blocks-with-Part-Off-Blade
Pretty sure it was this one! Thanks for the comment!
buy the 4 degree up parting tool holder for your quick change tool post.
Other viewers have pointed out some of your parting off errors, but have you considered using a rear mounted toolpost with the parting tool inverted?
Due to the mechanics of machinery...well that’s my vague understanding, parting off ‘upside down’ is easier and is less prone to the tool digging in.
Quite a few YT videos out there show the set up. You’ll need to buy or make a rear toolpost, though.
Use cutting fluid as well...aluminium is nice to cut, but it’s a ‘sticky’ metal with regards to cutting tools. WD40 or paraffin works well on aluminium.
Hi, thanks. I have actually got a rear toolpost but just not got the bits necessary for parting off yet. I’ll get around to it one day hopefully!
Where did you purchase the cutter and adapter please?
I'm pretty sure it was from Arc Euro Trade in the UK.
That’s great thank you.
I was was just watching the way you set the part off blade it would have been more easy if tou went to the face of the job then you could see how far the blades standout needed to be
How to make thread in 15 mm bar fast on manual leath
If it's a screwcutting lathe, you need the right gearbox setting and spindle speed plus the right screwcutting tool. Alternatively, you can use a tailstock die holder and either rotate the spindle manually or using a very slow spindle speed if achievable.
I just wanted to comment on all the things you did wrong but i see the other commentors have already covered that for me. So I will have to settle for telling you your work area needs cleaning.
What happened 4:23 . It didn't look good
It seems as if it dug in - he can be glad he got away with it.
I hope he posts the video when his luck has run out.
The video reminds me of my driving. I hav'nt been in an accident recently but it is not because of my driving skills - it's pure luck!
you had way too much stick out on your parting blade. not advisable. only pull out as much as you need .
Jamie Buckley Indeed, that makes a world of difference with these tools !
Absolutely right, as they used to say in star trek, you canny break the laws of phisics. and the longer something is the more it will flex. And to again quote, this time the great Renzetti, everything is made of rubber.
I don’t remember any lathes in Star Trek. Parting off with a phaser is much much easier.
ah the absolute POS "Dickson" type quick change tool post, best thing to do with these is chuck them in a scrap bin! go get yourself either a Multifix or a Tripan and keep the tool stick out to a minimum, oh and get a decent lathe too, like a Schaublin 102! :-)
U sound like fun at parties
Gee you can be blunt! Unfortunately though you are dead right. A blade in a lathe that size is not a good option. Single piece parting tools are much better. The hangout of the tool in a QC tool post is too large anyway and then to make it worse with a blade just makes no sense. I can't believe how folks try to part off any more than 3mm from the chuck. How does the cost of a Schaublin compare with a Myford?
@@smallcnclathes sometimes one needs to be. The speed, the over hang and that awful Dickson tool post!
@@smallcnclathes both decent Myfords and Schaublins fetch very good money here, in fact all machine tools have risen in cost during this pandemic! As for parting off, the Schaublin is more stable as it has less slideways, I’m only talking about the WW style Schaublins, I’m not sure about the screw cutting 102 series with a carriage and apron etc but I think they are more robust than a Myford .
@@crozwayne I did put up a lengthy comment of my own! I was just surprised at you being such a Cross Wayne, that’s all. Parting is aways a pain until one gets it right. Then it becomes just another part of turning. As I say in some of my videos, my parting tools cost me a lot of money, but they never let me down. Hundreds of thousands of parts all parted at the same speed at which they were turned.