Efficiently making straps from two layers

[Zac]

Hi Everyone,

I mostly make wallets but have been making the tote and backpack. I almost exclusively use veg tanned Kangaroo leather, it's a great leather and I find it gives me a bit of a point of difference to stuff from outside of Australia.

For making straps I cut by hand strips (I find the leather is too thin for a strap cutter or am I just bad at using a strap cutter?), then glue, sew, sand the edges, bevel, and then burnish. The whole process is really time consuming so I was wondering if there is anyone out there that has found the best method? I use a sewing machine but everything else is done by hand, preferably I would avoid buying a heap of tools!

 

Cheers, for any help! 

[fredk]

1. You must be using really thin leather. I can cut as thin as 1mm with my strap cutter

2. plan ahead. cut a wide piece of leather, enough for several straps. turn this over and glue to the main hide. then use a strap cutter to cut the double thickness in strap widths as needed. using a fresh sharp blade you'll get a nice clean cut edge which won't need any sanding

[Matt S]

Not all strap cutters are created equal, and the specific blades for them, I find, are absolute dog toffee. The typical cheap Chinese made cutters (including Ivan) tend to be hit-or-miss, whereas the one I got from Leather Works Prod Co is perfect.

Far better blades are the ones designed for injector style razors. Thinner, sharper, last longer and are physically longer, which lets me slip a blade downwards a few mm when it blunts, exposing fresh edge each time.

Of course you also need to adjust your cutter correctly to get good results. Ideally, adjust the daylight between the two bars to just smoothly pass the thickness of leather. Technique is simple -- pull the end of the strap slightly away from the rest of the hide, but not enough to bind or catch.

I am fairly well practiced with a well set up cutter and can reliably cut straps no more than 0.5mm difference when glued together, which I think means +-0.25mm tolerance per strap. That's with 2mm medium temper chrome cowhide, FWIW.

Of course the really efficient way to cut matching straps is cutting by die, or with a mechanical strap cutting machine. Maybe a laser, but then you get scorched edges and a long cycle time to deal with.

[Zac]

Thanks guys,

I will try glueing together before using the strap cutter. The kangaroo leather is around 1mm thick and it’s probably a case of poor user and maybe a dodgy eBay cutter. More practice should help!

But either way glueing first should save a lot of time.

Thanks again!

[Handstitched]

@Zac G'day from west Oz  

I too use roo hide for wallets etc.,  best leather for wallets  imo ,  but I also use roo hide for  making or repairing hand bag handles etc.  I haven't had much luck cutting thin leathers with a strap cutter either. 

To cut those, I simply use a metre ruler ( or 1/2 mtr)  pressing down as hard as I can , and my knife is super sharp . You could also use a sharp  rotary cutter, which is probably best...I just never got around to getting one myself ...old habits   

HS

[Rahere]

For the edge burnishing, use a dremel with a spindle-mounted head (I got mine from Proops, a man-toy shop originally on London's Tottenham Court Road, now on Etsy). Far faster

[fredk]

Proops sells through ebay as well. Though I'd hardly describe what they sell are 'man-toys' ~ they sell tools, tools for making things

https://www.ebay.co.uk/sch/Business-Office-Industrial/12576/m.html?ssPageName=STRK%3AMEFSXS%3AMESOI&_ssn=spoorp&_sop=15

I second the use of a rotary blade knife. Invest in a 60mm diameter blade one by Fiskars or Olfa. Not only are their blades superior but the knives themselves are more ergonomic. Plus, I've found, the best of these knives slide the blade down to the working position, from its safe position. The 28mm and 45mm knife blades don't clear the handle by more than about 1mm, not enough to cut through 1mm leather. The 60mm comes down further.

[Arturomex]

3 hours ago, fredk said:

I second the use of a rotary blade knife. Invest in a 60mm diameter blade one by Fiskars or Olfa. Not only are their blades superior but the knives themselves are more ergonomic. Plus, I've found, the best of these knives slide the blade down to the working position, from its safe position. The 28mm and 45mm knife blades don't clear the handle by more than about 1mm, not enough to cut through 1mm leather. The 60mm comes down further.

Agree with the rotary blade for cutting straps but I'm not quite clear on what you mean, Fred. I have/use both 45mm Fiskars and Olfa rotary cutters and the blade stays in the same place on the handle. It's the guards that move up and out of the way. There's at least 8mm of clearance between the blade edge and the handle on the Fiskars and I can cut 12 oz (4.8mm) veg tan without any problem. Of the two, I find the Fiskars to be more ergonomic for me.

Regards,

Arturo

[fredk]

Must be a difference in knife model. On mine, 60mm & 28mm, the blade guard remains fixed and the blade is moved out to the cutting position. I no longer have the 45mm, I passed it on.

Looking at the 28mm again, I reckon I can cut away some of the blade guard to make it more useful.

[Arturomex]

5 hours ago, fredk said:

Must be a difference in knife model. On mine, 60mm & 28mm, the blade guard remains fixed and the blade is moved out to the cutting position. I no longer have the 45mm, I passed it on.

Looking at the 28mm again, I reckon I can cut away some of the blade guard to make it more useful.

Gotcha. I've never seen the Olfa DX in the wild. What do you like about that better than one where the blade is fixed and the guard moves?

 

Edited November 1, 2020 by Arturomex

[fredk]

48 minutes ago, Arturomex said:

Gotcha. I've never seen the Olfa DX in the wild. 

My 60mm is a Fiskars, like this one; 

 

Push the orange thing on the top and it pushes the blade out to the cutting position, it also makes the orange button on the side pop out. Press that button and the blade snaps back in to the safe position

I'm not sure what make my 28mm is now, its got no name on it. I thought it was an Olfa. I've had it for several years now. Its got a head on I can set at any angle, in line with the handle. I store it so its in-line and set the head/blade at about 30 to 45 degrees for cutting

57 minutes ago, Arturomex said:

 What do you like about that better than one where the blade is fixed and the guard moves?

I cannot compare the two as I've only ever owned these ones

[johnv474]

Glue the leather first: two layers.  Ideally, slightly on a curve but ignore that for now.  Use something like contact cement or white glue like Leathercraft cement.  Glue is friendlier than cement.

Then, you have a few approaches.  Poke three dots for the width of each strap, which you line up along a straightedge to cut them out. Mark out all straps at once ans cut them at once.

A head knife, razor knife with a new blade, or a rotary cutter will make fast work of them.

If you use veg tan and tou use white glue then burnishing will be easier, but you do want the glue to dry under pressure for an hour or two.  I put a piece of glass over mine and then added weight, like books.

Big tip: when cutting along a straight edge, do not ever let your knife go past the fingertips of the hand holding down the ruler. Pause, move your holddown hand, continue cutting, and repeat.  If you got past your othwr hand you will wander from the line or will push hard enough against the straight edge to push it off your line.  Cut within the borders of your holddown hand, and avoid that forever.

[Zac]

Thanks for all the tips guys, I made some more straps tonight and using some of your advice it was much more efficient!