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WaggaSteve
20th October 2015, 04:43 PM
I see many sites selling metal carbide turning tools, presumably for metal lathes but enormously cheaper than wood turning carbide tools. What stops use of the metal ones in wood turning - too short (which begs the question of homemade handles ) or are they very different animals

Nubsnstubs
20th October 2015, 11:40 PM
If you look at the cutting edge on metal cutting tools, there really is no sharp edge to speak of. I don't know how it works, but it does. If you were to set one up for cutting wood, all you would do is burnish or burn what you are trying to cut.

I don't know what the angle is on wood turning carbide cutters, but it's over 7°, and possibly up to 14°............ Jerry (in Tucson)

Yanis
21st October 2015, 08:58 AM
No doubt they would work but the rake and relief angles are different on metal carbide tips. You would need to construct a holder but if you were going to do that then just buy the tips for the wood tools.

BobL
21st October 2015, 11:09 AM
I've used a few different metal working CT tips on my home made CT tool holder
See http://www.woodworkforums.com/showthread.php?t=76010

The tip shown in the photos is just the first one I grabbed out of my metal work turning gear.
It works OK but it was too aggressive compared to my regular HSS Chisels so I replaced it with less aggressive CT tip .
I haven't used it much because I do relatively little turning but I imagine it would be very useful if you have to rough out many blanks.
The finish can be quite good but not as good as honed HSS,

One thing that I imagine puts people off using them is that a diamond wheel is needed to touch them up
Last year I set up a 6" diamond wheel on the same spindle as a CBN wheel on one of my variable speed grinders so that I can shape and sharpen CT bits.

The wheel is a 180 grit from an on-line lapidary supplier and cost ~$20.
Details of the grinder and wheel are available here http://www.woodworkforums.com/showthread.php?t=188429

http://www.woodworkforums.com/attachment.php?attachmentid=329135&stc=1

Yanis
22nd October 2015, 09:06 AM
When I sold tools (way back in the 80s) diamond wheels were not that common but the fitters and turners used silicon carbide wheels to sharpen their carbide bits.

BobL
22nd October 2015, 09:40 AM
When I sold tools (way back in the 80s) diamond wheels were not that common but the fitters and turners used silicon carbide wheels to sharpen their carbide bits.

SC is fine for sharpening but not so good for shaping.
Diamond is not that fast either but is faster than SC.

Thanks to SWMBO's interest in rock and glass jewellery we now have a heap of different diamond grit wheels from 60 to 600 grit .

Heres the link (http://www.thk.hk/online-cart.php?cid=36&sid=39) to the THK store where we bought then and I note the price is US$8.50 for the 6" wheels and US$17.50 for the 8" wheels
Wheel sizes go up to 12".
The grits size range is 60 to 3000
Lots of other goodies in that store as well.

Ebay is even cheaper but often you have no idea what you are getting by way of quality and at leat YHK is reliable.

Yanis
22nd October 2015, 01:24 PM
Heres the link (http://www.thk.hk/online-cart.php?cid=36&sid=39) to the THK store where we bought then and I note the price is US$8.50 for the 6" wheels and US$17.50 for the 8" wheels
Wheel sizes go up to 12".
The grits size range is 60 to 3000
Lots of other goodies in that store as well.


Yes, technology has changed a lot since I first started there in 1977 :)

They were just installing a stock control computer for which they installed a specially air conditioned room and when you walked past there were men there in white lab coats looking important. They replaced a room full of typists with two console operators. Yes, I am that old!

John

BobL
22nd October 2015, 01:46 PM
Yes, technology has changed a lot since I first started there in 1977 :)

That was the same year my dad was made redundant.
He was a timber faller up until the late 60's then he was in a log truck accident which ruined his knees and back.
After trying various jobs for a few years he went back to school (he left in Grade 7) and managed to complete high school and got a job as one of a dozen payroll clerks for a large company.
In 76 the company computerised their payroll and he along with most of the other clerks was made redundant.