Here's a project that took me a while and during which I learned a lot!
I had never used a sawing machine before, and my work with leather was limited to one sheath for a knife I made and "man those fingers were indeed to close to this blade, lets stitchem' up". I tried to document as much as I could and take many pictures throughout the process but should anything remain unclear, feel free to ask in the comments.
Long story short, I recently bought a 1980 Honda CM400T and needed to transport stuff with it. A top case was out of discussion because I'm annoying and find them ugly :) I opted for saddlebags and started researching, originally with the idea of buying a pair, then considering tweaking a design to make my own as I couldn't find a model I liked in my price range... Let's begin!
I entered this instructable in the Travel contest, please consider voting for me if you liked it :)
Here's my matching tool roll, which I made at the same time using the same materials!
Step 1: Literature
The original inspiration came from the kickstarter page of Pack Animal. They make beautiful saddlebags but I simply couldn't afford the $ 1000+ for a pair of satchels and a tool roll + shipping and import taxes, but if you can, maybe you should go for it. Their products look amazing and seem sturdy. I mostly tried to reverse-engineer the satchels from the pictures and videos they have on their page.
I found on instructables a wealth of information about leatherworking, and sewing. Here's in no particular order about a thousand of URLs that contain information that I used :
Step 2: Materials
We want a waterproof saddlebag for rainy days: we need waterproof materials as well as a waterproof design.
I chose waxed cotton, which has a nice contrast with leather and is waterproof. As it wasn't thick enough for my taste, I used double thickness on most parts (more on that under step 4).
Then leather, of course, for structure and solidity. I used 3 mm (for the back piece) and 2 mm (for everything else) thick veg tanned leather I bought online.
For the inside lining, I opted for a thin beige cotton muslin.
In addition to those three main materials, we need:
Super resistant polyester thread (I chose the color of my waxed cotton)
Cotton thread for attaching the lining
Waxed cotton thread for the leather
Square shaped metal frames for attaching stuff (the english name is unknown to me)
Snap hooks for attaching to the motorcyle
Tragacanth gum (for burnishing leather, can apparently be replaced with saliva)
Step 3: Tools
As always, there are some tools without which you won't be able to make the project at all and the ones which will make it so much easier, but without which everything remains doable while a pain in the butt.
Scalpel or Xacto or a razor
Pens and ruler
Optional but nice to have tools
Leather marking wheel, gauge and knife
Leather burnisher (make your own by turning and smoothing a groove in a piece of wood)
Hole punch (can be replaced by a hand drill)
Step 4: Double Thickness & Lining
First, I doubled the thickness of the waxed cotton by folding it over itself, sewing together all sides but one, then pulling it inside out so the stitches wouldn't show. I did this for all the large pieces (front, back, flap). Everything is lined with beige cotton muslin.
Step 5: Front and Flap Pocket
I began with the front : it holds a one-fold accordion pocket which will have a leather flap (see next step). I first sewed the folds and top reinforcement on the pocket, then sewed it onto the front piece.
Step 6: Leather Flap & Leather General
The front pocket is closed by a leather flap, which I sewed on by hand using a so called "saddle stitch". Riding a horse and sewing at the same time is not easy but the result is worth it ;)
The saddle stitch is explained in detail in previous literature (cf. the leather working class for instance, or this page). Briefly, you stick two needles on both end of a strong waxed thread, then mark your stitch line with a groover and your stitch holes with an overstitch wheel, then poke through the leather with an awl.
I mean... This is theory. In real life, when you cheaped out on your awl and it breaks on your 2mm leather, you can do the same as me and switch to a dremel with a very small drill bit. Overkill but sooo much faster.
Then proceed to stitching (which I did before lining with the beige cotton so the stitch wouldn't show inside the satchel), and at the end go back a couple stitches and cut the thread clean close to the leather.
Pictured at the end is the burnishing of the edges of the leather - kind of like polishing by getting it hot and closing the pores. It's done by adding some sticky thing (gum tragacanth used here, other things such as saliva might work) on the edge and rubbing hard with a burnisher, in my case a piece of wood that I grooved to accomodate the edge. You rub it back and forth along the edge. By hand. Then again, that's theory, I put it in a rotary tool and burnished all my leather pieces faster than you can spell "lazy" ;)
Step 7: Snap-on
This pocket flap had to close somehow. I cut a small piece of leather to accommodate a snap on and affixed it according to the manufacturer's pictures.
Exciting step innit? Wait until you see how much hand stitching I did later on...
Step 8: Back and Compartment Separator
In the same way that I made the front, I made the back :) A couple of things differ: the pockets are flat (no accordion flap) and there's two of them. I aligned the on the bottom and they act as compartments of the main pocket of the bag. The small one holds my motorcycle log book, the big one can hold a 15" laptop.
Step 9: Sides
Again, no real difference with what was done before. The sides are made the same way, and (as pictured) are folded on the top over about 3.5 centimeters (looking back on it, this is a bit much and I would use 2 centimeters). This fold is also done on the front and back part and is a reinforcement of the opening of the bag's main pocket. It also serves as a "handle" to fold the pocket closed before putting the flap on. It's this rolling that keeps things dry inside.
Step 10: Put Everything Together!
The four parts were sewn together on the sides, then everything was pulled inside out. We're left with a gaping hole at the bottom and a gaping hole on the top... In this configuration, the bag won't hold much more than your crushed hopes for a decent bag. Let's add a bottom.
Step 11: Leather Bottom
This is a rectangular piece of leather. It is sewn on the bottom of the bag. It's the leather bottom. It will protect your bag from the roughness of the ground, and withstand the heat of the exhaust pipe which is not far away...
Pictured is my lack of a thimble. Or rather what I used to replace it, a piece of wood with a hole.
Step 12: Leather Backing, Snap Hooks, Belts and Handle
The leather piece in the back has to be the sturdiest as it is what will be rubbing on the motorcycle for extended amounts of time. I chose 3 mm thick veg tanned leather, in which I cut a rectangular piece of about 35*40 cm.
You have several functions to attach to this part: a handle, the closing belts and the attaching hooks.
First, I sewed everything to the back piece where it's going to be. I attached the hooks with rivets to make sure they wouldn't come loose when riding.
Then I sewed it to the bag. By hand. Kill me. (I counted the time spent hand stitching leather. 8 and a half hours total. no thimble. In three words: fingers, holes, redemption)
Oh but waaaaaaaait before you stitch the top part of the back: you need to add your main flap and it's pocket.
Step 13: Main Flap and Zipped Pocket
This is the kind of feature you might be tempted to overlook BUT it is this kind of thing that adds both functionality and cachet (en français dans le texte) to your bag. "The devil is in the details" but so is quality work: note the small leather patch to hide the ugly part of the zipper :)
Step 14: Closing Belts and Buckles
This is how the satchel is closed. Do not skip this step por favor
I'm afraid I don't really have the vocabulary to describe the steps here but the photos are pretty self explanatory, ask away in the comments if you need help I'd be happy to oblige.
I used a hole punch to make the holes in the belts but also to get nice round edges onto the leather parts that attach the buckles.
Step 15: Conditioning the Leather
I made my own leather conditioner from beeswax, jojoba oil, olive oil and pine essential oil. It both nourished the leather inside and out and makes it waterproof, just what me need! And you can use that stuff on wood too! Shout out to those two instructables:
Briefly, heat the liquid ingredients in a pot of simmering water (au bain marie) and melt the beeswax in them, then mix a lot and let cool slowly.
I applied it with a rag, heating the leather gently with a hair dryer so that it would melt and really penetrate throughout. Also, I used it on my old Dr Martens, changed the laces and they look like new.
Sorry the pics are blurry - I put my oily finger on the phone's camera :-(
Step 16: Sling Strap
This is to convert the satchel in a messenger bag for carrying it when you take it off the bike: just a strap of leather of about 3 cm width with square metal attachments (word please? i've no clue what those are called) at the ends.
Step 17: Attaching It to the Bike!
Exciting part when you learn whether the whole shebang is going to hold together or fall apart miserably. Yay.
I simply made two leather belts, with the same square things that I put at the end of the sling strap (previous step) and tied them around my saddle. The bag is easily snapped on or off and yet is secure!
I also made a fixture to keep the bag away from the exhaust and suspension, which I won't go in detail as every bike is different and it's not really relevant to talk about it here. I can provide more pictures if needed though :)
I mean it's a piece of a broom and two bolts. You don't want to see it, trust me.
Step 18: Extra Pictures Just in Case
That's it, you've made your very own motorcycle satchel/messenger bag! Good job and please ask any questions you have.
This was my first time really working leather and using a sawing machine, and I'm really happy with the way it turned out. Now I'm preparing for my road trip this summer, about 3000 kilometers around the south and west of France... Instructables coming up: how to camp from your bike, how to not cry when your bike breaks down for the third time in two days and how to survive eating only bugs that crashed on your helmet.
Thanks for reading, please consider voting for me in the contests I entered if you liked what you read :)