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brightspark
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is it a critical dimension and whats it for. you could use emery tape to clean it up and cover the lathe bed with cloth while its running 
Hood
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What tool did you use?
Did you use coolant or cutting oil?
The finish looks ok but like there has been smearing of the surface possibly by swarf being trapped behind the tool.
It could of course just be the camera as often cameras make things look worse than they actually are.
Did you use coolant or cutting oil?
The finish looks ok but like there has been smearing of the surface possibly by swarf being trapped behind the tool.
It could of course just be the camera as often cameras make things look worse than they actually are.
Used wd40.
2 different tools.
I don't think its smearing. Its the fine lines I don't like. Too smooth to feel with a nail though.
Perhaps a round nose tool will help?
Hood
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A larger nose rad can help but you will likely have to take a deeper cut, certainly if carbide. I personally always cut at more than the nose rad of carbide tooling.
As said though it may not look as bad as the camera shows it to be.
As said though it may not look as bad as the camera shows it to be.
Screwdriver
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With aluminium you’re probably better off with a nice sharp HSS shearing tool. Not tried it myself yet but it acts like a long flat forming tool and takes a shaving type cut.
Lathe will only hit 1000rpm sadly.
Yes very stringy swarf.
What is a polished insert tool?
northwest
Searching for the Holy Grail.........
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The big question is: What is the material? Yes, I know it is aluminium, but what grade? I realise that 1000rpm is flat out but I often turn biggish bits around 900 rpm without drama. Is it tempered stuff? 6262, 7075 ? I do see the edge dragging especially obvious on the extreme left of the last photo so it may be one of the softer types. It's all a bit of a balancing act to be honest, some of the harder stuff has a bit of copper in it so unsuitable for welding and the softer stuff is, well, soft. I will be doing a load of tempered stuff in a little while, I will take some pics.
Shox Dr
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Agroshield
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When you say, "is this finish OK?", what are you asking? Surface finish or surface roughness is something that is specified on a case-by-case basis for a particular application and particular process (turning, grinding, honing). It also can be measured in a standardised way, the same as length, mass or time can be measured. 'OK' or 'not OK' are not part of that measurement system. See:
https://www.ebay.co.uk/itm/Lathe-Ro...ss-Contrast-Template-Complete-pi/113347283562
I am somewhat astonished that you think a photo will assist you. That is the same as asking someone to snap a 25mm dia. piece of material and thinking the picture will give you any information on whether the part you are turning is 25mm dia.
Have a look on Google images for photos of typical surface roughness gauges and hold your part up against the monitor when it is displaying one of them. Determine the efficacy of this mode of working.
https://www.ebay.co.uk/itm/Lathe-Ro...ss-Contrast-Template-Complete-pi/113347283562
I am somewhat astonished that you think a photo will assist you. That is the same as asking someone to snap a 25mm dia. piece of material and thinking the picture will give you any information on whether the part you are turning is 25mm dia.
Have a look on Google images for photos of typical surface roughness gauges and hold your part up against the monitor when it is displaying one of them. Determine the efficacy of this mode of working.
MattF
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is it a critical dimension and whats it for. you could use emery tape to clean it up and cover the lathe bed with cloth while its running
As BS says, emery tape, (or a file), is your friend.
6082 - T6 is the grade I was using.
Hard to tell from the piccies - lighting makes a difference as well.
How do you think mine compares to yours?
Hood
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As you say, hard to tell from pictures.
Hood
I am obsessed.
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Nah, I am fine with that, don't do a huge amount of aluminium and what I do I get a decent enough finish with standard inserts.
