Flexure Cut Off Blade Holder

[welderskelter]

I seen a spring type cut off tool on you tube that impressed me . Course it dont take much to impress me.

[Mark Rand]

PeWe tools do a version for Multifix style toolposts.

https://pewetools.de/produkt/abstechhalter-fuer-26er-abstechschwert-at2090l-inkl-hss-klinge/

I've got one and it works very well.

[Bob La Londe]

Bob, you're not wrong about seeing that style of flexure holder in the past week. I'm pretty sure it was well displayed in a YT video that I also saw. But like you I hope no one asks WHICH video. The method also struck me as being very home shop friendly.

It's worth noting that the flexure web in your sketch is only the width of the one saw cut running down from the top. And the narrow width of that means that you will need to strictly limit the amount of movement needed so that small area isn't stressed into cracking.

Your sketch also includes a height adjuster. But the sketch shows a bar which would clamp into a holder that has its own height adjuster. So really that whole top between the mounting bar and the part with the setscrews could be relieved down to just over the height of the securing bar and make for a much wider flexure joint which would give a zero risk of any stress cracking.

Yep!

The adjuster is an unintentional misdirect. I should not have put one on this part.

A buddy of mine loaned me (no particular time limit) an insert type parting blade to try out. This is the new "backup" blade in umahunter's shop, so I only need to run it back right away if he jacks up the one he is using. He has a smaller lathe and is using a 2 piece block similar to the one in post #4. I could make one like that, but I have kinda fallen in love with the flexure type holder idea.

My intention is to make a holder that is a very close fit to try it out. If I really like the blade I'll buy one (probably two so I also have a backup) with some inserts. There will not be much flex needed in the flexure.

[BCRider]

Bob, you're not wrong about seeing that style of flexure holder in the past week. I'm pretty sure it was well displayed in a YT video that I also saw. But like you I hope no one asks WHICH video. The method also struck me as being very home shop friendly.

It's worth noting that the flexure web in your sketch is only the width of the one saw cut running down from the top. And the narrow width of that means that you will need to strictly limit the amount of movement needed so that small area isn't stressed into cracking.

Your sketch also includes a height adjuster. But the sketch shows a bar which would clamp into a holder that has its own height adjuster. So really that whole top between the mounting bar and the part with the setscrews could be relieved down to just over the height of the securing bar and make for a much wider flexure joint which would give a zero risk of any stress cracking.

[Bob La Londe]

The adjuster is an unintentional misdirect. I should not have put one on this part.

[Bob Engelhardt]

I first interpreted your sketch to mean something like this:

[Bob Engelhardt]

Here's an interesting & very simple one that uses side clamping, but with a 2-piece wedging action; the force being supplied by the holder:

https://www.aliexpress.com/item/4001243858781.html

[Bob Engelhardt]

EDIT: Never mind (brain fart) - I didn't see that ledge on the bottom where the blade would sit. I still like the idea of clamping on the edges.
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The one that you sketched is fundamentally different from the others in that although the blade is supported on the bottom, as it has to be, it is clamped by its sides. Which means evenly along the whole length of the holder. I like it!

If you make one (please do), be sure to post about it.

[mikey553]

Somewhere In the last week I saw a one piece cut off blade holder. It was machined away on the back to fit into a 250 style lathe bit holder. The front was machined wide (high) enough for an insert type parting blade. At the time I thought that makes perfect sense. I'm going to make one. Now my brain is messing with me. I did a quick pencil sketch, but it just doesn't look right. Like I am missing something. Has anybody seen a cut off blade holder along these lines recently? Got a link?

If you going to make a holder, may I suggest a direct mount to your post. This way the blade overhang will be smaller and your tool will be better supported by the compound. I was thinking to do just that for my BXA (250) post, but bought a 2 pc version from Shaars. May still do it one day...

[Noitoen]

Sorry, missed the flexure in the title and I certainly should have seen that feature in your sketch.
The only type I remember seeing with a flex type grip is also made by ABM tools, among others I'm sure.
Although the concept is somewhat similar the execution is vastly different.

I've made one of these to hold a piece of regular hacksaw blade sharpened as parting blade.

[Bob La Londe]

Iscar and Kennametal both make the type you are looking for-

https://www.dansdiscounttools.com/pr...ock-a2ten1632/

If you build one, I can suggest an improvement. Add a couple fine thread setscrews in between the clamping bolts to jack the flexure open making it easier to adjust the stickout. The ones I have used are tough to slide the tool into/through without tapping the blade with a hammer and Aluminum block.

Here's the Iscar version-

https://www.ebay.com/itm/12371826534...oAAOSwkV5aaPHx

Jack screws is a good idea. I hadn't thought of that.

Sorry, missed the flexure in the title and I certainly should have seen that feature in your sketch.
The only type I remember seeing with a flex type grip is also made by ABM tools, among others I'm sure.
Although the concept is somewhat similar the execution is vastly different.

Now that's a different way of doing it. I like that one too.

[wierdscience]

Iscar and Kennametal both make the type you are looking for-

https://www.dansdiscounttools.com/pr...ock-a2ten1632/

If you build one, I can suggest an improvement. Add a couple fine thread setscrews in between the clamping bolts to jack the flexure open making it easier to adjust the stickout. The ones I have used are tough to slide the tool into/through without tapping the blade with a hammer and Aluminum block.

Here's the Iscar version-

https://www.ebay.com/itm/123718265349?hash=item1cce2eea05:g:k7oAAOSwkV5aaPHx

[Willy]

Sorry, missed the flexure in the title and I certainly should have seen that feature in your sketch.
The only type I remember seeing with a flex type grip is also made by ABM tools, among others I'm sure.
Although the concept is somewhat similar the execution is vastly different.

[Bob La Londe]

One something like this Bob? I think I may even have one like it....somewhere.

https://www.abmtools.com/product/parting-tool-holder-for-blades/

That is sorta similar, but the one I saw definitely one piece with a flexure.

[Willy]

One something like this Bob? I think I may even have one like it....somewhere.

https://www.abmtools.com/product/parting-tool-holder-for-blades/