Turning a large aluminium piece on the SC2 mini lathe
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- Опубликовано: 7 сен 2024
- Turning a 76 mm (3") diameter piece of aluminium in my SC2 mini lathe. I still have problems with chatter, but towards the end of this video it turns really nicely.
Love it, nice learning curve. With Aluminium, Positive rake and good clearance is your best friend and a little CRC or even oil still works well. Maybe lock the cross slide when facing to. Please keep these videos coming always worth the watch. Thanks.
Don't worry for a beginner your doing great these suggestion are just to help. And the reason so many we as a unit like helping our fellow you tubers.
Lol that reverse pass cleaned it up nicely
Samuel,
The nibs after parting off are a fact of life. Rarely is a piece parted off cleanly.
After you angled your tool a bit you discovered the chatter lessened quite a bit. Thirty degrees is not excessive and most machinists set the compound at 29 degrees and leave it there for most operations.
Aluminum of any kind is difficult to get a pristine finish with a hand fed cut. The interrupted movement creates the line pattern. Some have made attachments for cordless drills to facilitate more even movement. I’ve tried it but for me there are so many things going on while turning adding one more thing to do is counterproductive.
Swarf is the bane of aluminum, especially the long, stringy chips, quite pretty, but a nuisance. There are carbide inserts especially ground for this material but still do not break the chips adequately in my opinion. Also you will find in using HSS or carbide bits of aluminum will weld to the cutting edge as the tool heats up. Sometimes it’s just a matter of scraping it off with the edge of a file or knife. If the weld is severe the tool has to be re-ground.
I know I and others have offered this advice before but the more solid you get that little machine the more satisfied you will be with it. I know the machines come with rubber feet and are marketed as being portable but the stresses of cutting metal are considerable and far exceed portability and the capacity of the rubber to absorb the vibrations. (Only The Beach Boys are able to endure “Good Vibrations”. Lol)
As for your comments about people enjoying watching someone with no lathe experience we are all on a learning curve here and most of the advice given is from those of us who have been right where you are now and give comments on how we approached and solved the problems.
Machining, even with a small mini lathe can be an extremely satisfying endeavor as each little quirk of these machines are conquered.
Dale
I think you nailed it right at 8 sec mark.
It looks like you have insufficient clearance (front), try angling the tool around slightly to avoid excessive friction and allow clearance for swarf. Remember that you should have top, front and side clearance. Have a look at the technique of grinding tools on a grinder, it should show what I mean.
YOUR !! LATHE !! LOOKS !! ABSOLUTELY !! READY !! FOR !! THE !! METAL !! SHREADDER !!! NOW !!!
My opinion is that your lathe is flimsy or not securely attached to the work table. I noticed how it shook when you cranked the tool back after facing the piece.
Indeed it isn't securely fixed to the work table. It isn't fixed to it at all! That's why it shakes with respect to the camera which is on a tripod on the floor. But I don't see the relevance of that to the issue. The rigidity I need is between the tool and the chuck (via the top slide, the cross slide, the saddle and the lathe bed).
Hi. I’ve bought this lathe and the Chinese quick change tool post. Can I ask how you use/slacken the original tool post please? I’m ready to go however, the tool post handle won’t budge. Thanks in advance.
I can't remember much about this, but my recollection is that it just unscrews in an anticlockwise direction. So I suggest apply more force
@@samuelfielder thanks fella. I’m on to Axminster waiting on an email response. Once it’s off though is the Chinese quick change post easy to fit. I’ve got the same one as you. Love the videos by the way. Michael
@@michaelchatt2639 Yes. It's just a matter of unscrewing one and screwing on the new one.
@@samuelfielder thanks again mete. Axminster have suggested some wd40 and a gentle tap. Failing that they’ll replace the whole lathe. I’ll let you know the outcome
@@samuelfielder fitted the tool post. Although I can’t fit the original black handle like you have. Any idea why Samuel?
WD40 helps to lube the Al stock and feed with a cordless drill on slow with a cheap cut off Allen key. Doing great though.
👍👍 I think you need lube and you need to secure lathe to table with all the pressure from tool cutting into part you get bed twist and chatter. And i can see flex in your compound may need to adjust gibs a bit. And tool seems to be rubbing may neet to regrind with 6°relief as shown in tool grinding on you tube videos.
Thanks. When I have time I'll build a hefty table.
Oh dear oh dear !
BETTER !! HAVE !! ANOTHER !! CUPPA !!!! CHAR !!!
Is your cutter a fairly quality cutter? I’ve seen some where the cutter was terribly low quality, claiming it’s carbide or quality tool steel. Is there any play in the hand wheels, chuck, headstock or pulleys. Could it be the work piece too big for your cutter? Your cutter length rubbing work piece, as you feed in?
Thanks. I thought the tools were all good quality but I think now they are M2 steel which is without Cobalt, but they cut aluminium very easily (it seems to me). There's always some backlash in the hand wheels, not elsewhere. Yes, I did have the tool wrongly angled for the facing cut, initially. Not sure what you mean by workpiece too big for cutter. I should have angled the top-slide at 45 degrees to allow facing in one movement.
As far as the work piece being to big for the cutter, with those types of machines its a blind "hit or miss", my good friends son had a very similar lathe he used to make pens with, as a novelty, the kid wanted to make an over sized Yo Yo, with thin walls, the yo yo being 3" (76 mm), just about the capacity limit of the chuck, he suffered similar troubles as you, wanting to see the kid's process of machining this sized piece, i found no matter what the kid did, he would get chatter. when i fiddled with it, i had to speed and feed very slowly, which was very bad on all levels, including the tool cutter, which was a 3/8" cutter, for the machine. So i figured, I machine a one solid, tool post (eliminating compound slide for this project) with the ability to hold 1/2" and larger tool holder/cutters, though it made the small lathe a little "Frakensteinish", at the time, we found any size tool cutters (small to large) would work. I then found Robrenz and Steffan Gottswinter videos had built similar tool posts. so, if you wanted, you could probably try this route.
The rigidity is my point. Unless the lathe is firmly attached to the stand or table, you'll never get the rigidity you're talking about. Please try it!
Well I might - despite not following the logic - as having the lathe bouncing around relative to the camera is a nuisance.
I also think you would be better off having it bolted down to a heavy worktable, with the machine vibrating like that i i can imagine there wont be very stable cutting, this is usually never an issue when working "normal" sized lathes as they are far more sturdy than these things and sit steady on the ground just with their weight.
Don't ever leave the key in the chuck. Not for a second. Made my eyes water.
BOOP !! BONG !! WRONG !! ANSWER !!!!!
I was looking at buying one of these lathes but that was some painful viewing.
It sounds absolutely terrible and vibration looks awful.
Is this typical of thos lathe?
Thanks David.
Yes, but bear in mind I was very inexperienced at the time. Hae a look at blondihacks channel. She is an experienced machinist and uses a small lathe successfully.
Keep safe,..no sleeves, take out swarf with a tool (stick) never bare hands .
You need more inertial mass! Epoxy granite filling is the keyword. Nonetheless thanks for the video
Hi Samuel, I often see the thumbnail for this video when I am on yt as it comes up as a suggested video.
That swarf is horrible, were you using machining grade aluminium? It makes life much easier for the machinist. I am not aware that the price is any different. I will only NOT use it when the customer needs to anodise or weld the part.
A carbide "finishing" insert could work well for a lathe that. This may help you get swarf that is more controllable.
Looking forward to the next video with a suit of small sails.
Haven't a clue what type of aluminium it was. Bought off ebay but it was clearly something that had been left over after machining. I don't know why this video has attracted more interest than most, because I really am only blundering around in the dark re. machining. Perhaps people enjoy watching someone who clearly doesn't know what he's doing!
No doubt it was machined. Large lathes with lots of horsepower can rip into the other grades of aluminium without a problem. It is smaller machines like ours that need the right alloy to work nicely. Anyway now you know it exists and if you have a bit to do It may be worth trying for a machine grade aluminium. Next Woodstock video??
Thanks. Working on next video but have been busy and we have difficult edit to do.
@@smallcnclathes i cut all kinds of aluminum brass bronze and stainless all in your tool.
CAN !! YOU !! CONTROL !! SWARF !!!???
turn your tool at 45 dagrees
Yes. I thought of that after I'd done it.
you have your tool wrong setup on the lathe
In what way?
tooling should be about 35 to 40 degrees from the job should cut on the point of the cutter not the side of it
SOUNDS !! LIKE !! B.S !! TO ;! ME !!
you are to close to your work and also to much of your cutter is hitting work pice little angle
Yes, that's why I rotated the toolpost anticlockwise halfway through, but perhaps not enough?
HIS !! BIG !! NOSE !! KEEPS !! GETTING !! IN !! THE !! WAY !!!
Get rid of that Chinese aluminum tool post holder. Your angle of your tool is set wrong. Watch abom79 he will educate you
NO !! ITS !! ACTUALLY !! THE !! METAL !! SHREADDER !!!
Some of the chatter could be your tool post these aluminium posts are just junk
Yes. I tried to see this by filming lathe from two directions close up, but the result was inconclusive. I hgave tried using the chunky steel tool post that comes with the machine, for parting off, but I think most of the movement is in the gibs.
THE !! ENTIRE !! LATHE !! IS !! COMPLETE !! TOTAL !!AND !!! UTTER !! UTTER !! UTTER !!! JUNK !!!!!
you have your parting off tool is to high
Don't think so. It was dead on centre.