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WaggaSteve
10th Nov 2016, 07:51 PM
Is this a stupid idea - using a hacksaw while lathe turning to part off

artful bodger
10th Nov 2016, 07:58 PM
Not if it is attached to the correct hack saw handle, and you are wearing eye protection.
I am assuming you want to part off with a cut way finer than your trusty parting off tool for some reason.
I have heard people say using a hand plane to true up large turnings while the work is spinning is also a bad idea, however it works a treat!. Even seen a bloke turn nicely with an axe.

GeoffW1
10th Nov 2016, 08:58 PM
Hi,

It is downright dangerous unless you have the job turning very slowly. Even then...think of it - a jam-up at 200 RPM.

Take care

BobL
10th Nov 2016, 09:10 PM
I use a short length of hack saw blade shaped appropriately as a parting tool for small brass and Al work on a metal working lathe but its held by a sturdy tool post parting blade holder.
Can see why it the same can't be used on a WW lathe for small stuff provided a suitable holder/handle was made.

artful bodger
10th Nov 2016, 09:43 PM
Hi,

It is downright dangerous unless you have the job turning very slowly. Even then...think of it - a jam-up at 200 RPM.

Take care


What is dangerous Geoff?

DavidG
10th Nov 2016, 10:38 PM
Used hack saw many time on wood and metal with appropriate blade. Just remember to keep the blade moving otherwise you destroy a tooth.
Wear std safety gear and don't press hard.
I usually do it at 60rpm.

Kuffy
10th Nov 2016, 10:46 PM
I have heard people say using a hand plane to true up large turnings while the work is spinning is also a bad idea, however it works a treat!.

I havent seen anyone do this, but I was thinking about doing it about a week ago. It seems like a bad idea but I cant figure out what the damage to me or my lathe will be if it goes wrong. I would move the toolrest out of the way so I cant guilotine my fingers. But it still seems wrong which makes me think about it a little further before doing it.

edit: never mind, curiosity got to me. I just YouTubed it. It is awesome.

Mobyturns
11th Nov 2016, 02:01 PM
Is this a stupid idea - using a hacksaw while lathe turning to part off

I'm not a fan of that idea at all.

Have you ever jambed a parting tool while parting off? What would be the result if the hacksaw blade became jambed in the cut? & with a hacksaw frame attached? How would you provide clearance in deeper cuts?

joe greiner
11th Nov 2016, 05:10 PM
If memory serves me correctly, a few years ago in a thread about using a hand plane, our Benevolent Dictator claimed that he'd once turned wood with a shovel.

On a few brave occasions, I've parted small work with a Japanese pull saw with the lathe running. The cut should be made on the bottom of the piece, not above as with a normal parting tool. First, because the saw will escape away from you or toward the lathe bed instead of at you, which would be most unpleasant. Second, the piece at imminent separation spans between the headstock and the tailstock, and therefore sags; the gap allows departure of the saw instead of being pinched by the work if it were cut above.

For extremely miniature work, I've used a utility knife, also cut from below.

Cheers,
Joe

Skew ChiDAMN!!
11th Nov 2016, 05:41 PM
It's not a stupid idea... unless it's approached in a stupid, non-thinking way.

Every method for parting off with the lathe turning has some risk involved if not done correctly. (Hell, this can be said to hold true for any operation involving any power tool! :D)

As a rule of thumb: if you're not sure whether it's safe, the answer is it isn't!

powderpost
11th Nov 2016, 09:17 PM
I have , for a number of years now used a section (about 225mm) of a machine hacksaw blade as a parting tool. Mind you it has a stout wooden handle firmly fixed to it. I would not use a hacksaw blade as a saw, or even a conventional hand saw, to cut timber on the lathe while the lathe was in motion. Even while the lathe was still, it would be grossly inefficient and the cut would be difficult to control. Use a conventional hand saw, that is what they are designed for.

Jim

woodPixel
11th Nov 2016, 09:20 PM
One of the very best parting tools I have is the skewchigouge.

Man do I love that tool. It is so versatile.

Its shape allows it to get right down and do fine details and sharp parts on tight areas.

A skewchi is easy to make with a round bar stock.

GeoffW1
11th Nov 2016, 09:28 PM
What is dangerous Geoff?

Bodger, I'm surprised.......

Here you have the job turning fast (remember, that's what I said above), and you lay the hacksaw blade on it. Have you remembered to throw it in reverse so at least the hacksaw smashes into the wall and not your face?

Then you get a bit of depth in the cut and the blade jams. You bet it won't, ever? What then?

I'm not just blowing hot air, Bodger, I saw it happen once. The kid got 2 broken fingers and he was lucky.

Anyway, all the best with that ;-]

artful bodger
11th Nov 2016, 10:11 PM
It seems we all have our own thoughts of what is safe and proper.
To me a hacksaw blade aint going to break your arm, no matter what goes wrong.
There are videos out there of blokes using chainsaws to hollow out bowls on rotating blanks spinning on a lathe.
Guess it depends on what you are comfortable with.
Skew chi damn, sums it up pretty well.....
"As a rule of thumb: if you're not sure whether it's safe, the answer is it isn't!"
Regardless, I am excited by those who push the boundaries.

Rod Gilbert
11th Nov 2016, 10:53 PM
I have a length of standard hacksaw blade in my turning kit that I have used many times as a parting tool for fine work sharpened the same as a standard parting tool it works a treat when treated with the same respect as any turning tool.
Regards Rod.

hughie
12th Nov 2016, 09:26 PM
I have had a couple of heavy hacksaw blades shortened and sharpened as parting off tools sitting in my tool rack for many years now. Approx 40mm wide and around 2mm thick HSS .
Now are they dangerous? Hell yes, but then everything to do with a wood lathe is.

Mobyturns
14th Nov 2016, 11:33 AM
Guess it depends on what you are comfortable with.


There in lies the answer! Some people are apparently fearless and oblivious to potential hazards, others take the time to stop and think - what if?

I'm one of the latter, so I look to others with experience and knowledge for guidance. Using a part of a heavy section machine hacksaw blade with teeth ground off as a parting tool is a fairly common practice and is generally considered a "safe practice." However using any form of saw with the lathe running is a very uncommon practice - for a reason - it injures people.

Most turners wishing to part off a larger piece from the tenon / waste block will start the cut with a parting tool then stop the lathe, engage the spindle lock, remove the tool rest then cut the remainder with a hand saw or Japanese saw. That really does not take much physical effort so why take the risk of using the saw while the lathe is turning???

I would really be questioning - why the need to use a saw at all to cut off the work piece? Surely you will have to finish the cut surface, so perhaps there is a better way to approach the task.

Now if you are using the saw to part off an unsupported (no tailstock support) small spindle item with a short length of hacksaw blade in a suitable robust handle - then that is an entirely different scenario with a much different hazard profile.

There are no universal truths in wood working / turning - as the yanks say - your mileage may vary. Horses for courses.