Chinese band knife splitting machine

[Veredaverde]

https://www.leathercraftpattern.com/Leather-skiving-machine-world-free-shipping?sort=p.price&order=DESC

Is anyone familiar with this machine?  It’s much lighter than other band knife splitting machines. 

[Danne]

Even if the machine do work decent, what happens in a couple of years when maybe that machine doesn't exist anymore, and you need spare parts? 

If you can afford it, I think the Camoga Compact for 12-13000usd is a better choice.

Also depending on what you make you can learn to split leather with good results for smaller leather goods with a skiving machine.

 

[DrmCa]

That's a lot of $$ for a cat in a sack. What sort of work are you looking to accomplish on it?

[chrisash]

Hell of a lot of leather the right size for that money unless you are turning over lots of leather

[Danne]

51 minutes ago, chrisash said:

Hell of a lot of leather the right size for that money unless you are turning over lots of leather

The problem is what is the right size? Today maybe you need 0.8mm or 1mm or 1.5mm for a watch strap. Next time you need the same leather in three different weights for a wallet/card holder. Also buying directly from tanneries is not an option without a splitter (With very few exceptions where you can get the hide split, but then it's the whole hide in one weight)

But for hobby use a bell knife will go a long way. Nitz as example split his leather for small leathergoods with a skiving machine. 

Edited January 18, 2022 by Danne

[Matt S]

On 1/17/2022 at 4:59 PM, Veredaverde said:

https://www.leathercraftpattern.com/Leather-skiving-machine-world-free-shipping?sort=p.price&order=DESC

Is anyone familiar with this machine?  It’s much lighter than other band knife splitting machines. 

I saw this a few months ago and am really curious to tear one down. If it works it'll be a massive game changer, certainly for the hobby leatherworker.

I have a "real" band knife splitter, a Fortuna UA. It's a pretty standard 12" model but a little old fashioned. Weighs 800lb including the cast iron frame and stand, 4x induction motors totalling 1.5KW, and the precisely machined steel adjustment mechanisms. Modern equivalents weigh about half that.

Before I got my machine I was shopping Camogas with the UK dealer. The chap I spoke with said that they are still so massive (in volume and weight) because that's what's needed in order to tension the knife without distorting the frame. Just no getting around it, basic physics. Having now been elbow-deep in my Fortuna many times I completely understand. That's the first red flag to me about this desktop version: it doesn't seem sturdy enough to withstand the tension needed on a standard band knife splitter blade. I suspect that it's not a full width blade, to avoid stress on the frame. If the blade is narrow it'll have a relatively short life and be more prone to variation in split (the leather will be more likely to veer into or away from the blade).There may also, in the real world, be an excessive distortion of the frame causing things like blade crashes or splits that vary across the width of the leather.

The blade sharpening is another issue for me. Band knife splitters, like most edge tools that work on soft materials, absolutely rely on a perfectly honed blade. Leather is an abrasive material and so the blade needs sharpening frequently. On "real" band knife splitters there are a pair of emery wheels which sharpen both edges of the blade at once, to prevent burrs. This may be adjusted for either constant or just frequent grinding. The desktop model appears to use sticky-back sandpaper to sharpen the blade, which I would think would cause a lot of problems with uneven bevels, clogged sandpaper, and being inconvenient enough to not happen as often as needed. The size of the knife wheels can't be very big either, which again hints at maybe a skinny blade or one that's likely to crack prematurely.

Just like with a bell-knife skiver scrap sticking to the feed wheel is a common problem when operating a band-knife splitter. The solution is largely the same: a vacuum extractor which pulls the scrap away as soon as it's free. There doesn't appear to be one on the desktop model. This may also be a health hazard as the same system captures dust (from the leather and from the knife grinder) and keeps it out of the operator's lungs.

Band knife splitters have a bewildering range of adjustments, mostly for spacing, parallel and tension/tightness. All have to be very nearly dead-nuts-on to work reliably and "want" to shift with vibration, or even to adjust mid-split due to the forces exerted. Frankly I have seen few Chinese-made mechanical devices where the adjustments were accurate, smooth or held tension well. I know that not all Chinese products have screws made of cheese but colour me sceptical by experience. As a result reliability, repeatability and accuracy are likely to be suboptimal. There also seems to not be enough physical space in the machine for half of the necessary adjustments, which would leave them factory-set and prone to wear.

Speed also seems to be something that the desktop splitter doesn't do well. That's not the end of the world because it's not exactly a production machine but I bet splitting the components for a half-dozen billfolds would get very boring very fast.

It is my repeated experience that electrical safety of direct-from-China machines (rather than made in China to Western design/spec machines) leaves a lot to be desired. This a mains powered metal cased machine. I make it a policy to check the wiring of any mains powered machines that don't come through a proper UK dealer. I have never wasted my time by doing so, and never had to not correct a design or manufacturing fault or shortcut. Similarly mechanical safety may not be up to snuff, certainly for use in a workplace, but I'm not well qualified to discuss that.

Finally, it looks like feed roll tension is adjusted with the pair of silver hooks under the front. They look like they're straight off a bell-knife skiving machine. I doubt they're up to taking much tension, and certainly don't have much "granularity" of adjustment (5 steps IIRC). Maybe the fine adjustment is what that wheel's for. It certainly doesn't seem to be up to the sorts of tension I have experienced on a "real" band-knife splitter, though admittedly I have only run a grand total of two. For reference I weigh about 160lb and have to put at least a quarter of that on the pedal to counteract the tension on my Fortuna.

1 hour ago, Danne said:

The problem is what is the right size? Today maybe you need 0.8mm or 1mm or 1.5mm for a watch strap. Next time you need the same leather in three different weights for a wallet/card holder. Also buying directly from tanneries is not an option without a splitter (With very few exceptions where you can get the hide split, but then it's the whole hide in one weight)

But for hobby use a bell knife will go a long way. Nitz as example split his leather for small leathergoods with a skiving machine. 

Well that depends on exactly how "tolerant" an individual may be on thickness. 0.1-0.2mm thickness variation across a hide is pretty standard these days and for most projects there's a fair bit more leeway available. I'd say that location on the hide, grain orientation and choice of hide for appropriate hand/texture is probably important than getting exactly the correct thickness to the nearest 0.1mm. I understand that having leather split can be difficult with minimum orders but once we're talking about plonking down $5K you could probably afford to get every hide you're likely to use split to every thickness you're likely to want.

100% with you regarding the bell knife skiving machine. I just hate adjusting mine (never been much good at it) so once it's set for a job there it tends to stay until I really need to adjust it for the next one I can't do without it!  

[kgg]

On 1/17/2022 at 4:59 PM, Veredaverde said:

Is anyone familiar with this machine? 

I am not familiar with that machine but for those dollars I would be concerned with the lack of dealer support and down the road for repairs and access to replacement parts. Maybe better off getting a good used machine that has dealer support.

kgg