Manche en cuir: comment... ?

[Hellmut]

Bonjour

Je m'attèlerais bien à la fabrication d'un manche en rondelles de cuir empilées/collées/pressées/poncées.

Ma question est la suivante: comment, au final et sachant que ce n'est pas du bois, obtient-on un fini aussi régulier et luisant ?
Faut-il finir avec une quelconque résine epoxy puis reponcer ? Je suis perplexe.

Merci de votre aide !

[saul31]

La bible :

http://www.britishblades.com/forums/showthread.php?13253-Leather-handled-knife-tutorial&highlight=tutorial

[Hellmut]

...dont je vais citer l'extrait correspondant pour future référence rapide afin que ce topic facilite la vie aux suivants:

1. Quick hard leather finish.

This finish is the one to use if you want a maintenance-free handle that is completely waterproof and behaves just like wood. None-knife people will usually be stunned by the beauty of it. Particularly because it doesn’t feel like leather at all.

Sand the leather gently to 240 grit, then apply a drop of cyanoacrylate glue and immediately rub it over the whole surface with a latex or vinyl gloved finger. You are not trying to saturate the leather, just stick the surface fibres together. Leave it for about half an hour, then sand with 240, 320 and 400 grit abrasives in turn. You should start to see some loose fibres coming through at this point. Repeat the cyanoacrylate step. This time sand with 240, 320, 400, 600, 800, 1000, 1500 and 2000 grit abrasives (Fig 15).

Figure 15



At this point you can treat the surface as if it were wood. CCL Traditional English Oils and Polishes make two finishing sets that are gorgeous, the knife Handle Polish set (supplied by Brisa) and the Knife Handle Oil set. The polish set uses a fine lacquer base which is then mixed with oil to give a gorgeous sheen, superb for collector’s knives. The Knife Handle Oil set is better for working knives; it uses a sanding sealer followed by a conventional, but rather light oil. Either of these finishes will work well to give a hard very attractive surface that requires virtually no maintenance and has none of the traditional properties that make leather handled knives so attractive to knife users. Frankly any technique you use on wood is worth trying. If you want to colour the leather, use a spirit dye between the first and second coats of cyanoacrylate.

2. My version of a traditional finish.

This is my favourite finish. It takes several days to do well, is rather less pretty than the hard finish, but gives you a real leather handled knife. For this finish, you need a good quality soft leather grease. Gold Quality Laederfedt (from Brisa) or Pecard’s leather dressing work equally well. You also need some gum tragacanth and good quality abrasive sheets from 180 grit to 2500 (Axminster cloth backed are ideal).

Sand to 240 grit as usual, using a light action. Now rub some grease into the leather with your fingertips (Fig 16) Massage it in quite hard for a few minutes, then leave it to settle for half an hour. Wipe off any excess, then sand very lightly with 320 grit abrasive. Rub in some more grease, wait half an hour and sand with 400grit abrasive. Repeat this for 60, 800 and 1000 grits, then substitute a drop of gum tragacanth in place of the grease. Rub this in very hard with vinyl or latex gloved fingertips (helps the polishing). Leave for half an hour, then sand with 1200 grit abrasive. Do the same for 1500 grit, then leave it overnight. The next day, rub in some leather grease very gently and sand with 2000 grit abrasive and repeat for 2500 grit. Leave it overnight again and finally, just rub in some grease, polishing with a cloth.

There are a number of minor modifications you might try. For example, if you have a buffing machine, or an attachment for a pillar drill to take a buffing wheel at low speed, you can buff the handle with pure hard bees-wax after the gum tragacanth stage and call it quits. This gives a lovely firm, but non-slip grip. If you don't have any gum tragacanth, you can just buff with bees-wax after about 1500 grit and leave it at that.

If you have the resources, try out all of these options on your finishing block and see which you prefer.

Figure 16 and 17





You now have a perfect finish. A handle made like this will give a secure non-slip grip in any conditions; it will absorb sweat and be quite cool on hot days, will be warm on cold days and will require regular weekly greasing for the first few months and once every three to six months (depending on use) thereafter. This finish will age beautifully if cared for properly. It is not a finish you are likely to find on a knife by a commercial maker, because it is labour intensive and takes days. A situation where those of us who are strictly amateur (those who do it for the love of the thing) and don’t have to account for every minute spent are at a profound advantage.

You choose…. Basically neither of these is the “correct” finish, they are both good for different uses and different people. Fig 17 shows each of these finishes on my block, together with a traditional finish over a spirit dyed base. It is obviously impossible to convey much useful information about the nature of the finishes, particularly their tactile characteristics, in a photograph, so it really is important to try them out before you start messing with your knife. If you get into the hobby of making stacked leather handles, you will probably find yourself spending hours playing with these little blocks. It is habit forming…. Would it be better to use the gum tragacanth a bit earlier in the process, or maybe not at all? When is the best time to stain the leather? What with? How about buffing with carnauba wax? Would the hard finish be better if you only sand the cyanoacrylate layer lightly to a polish, or all the way through to the bottom? Etc etc. Maybe this is just because I can’t stop being a scientist even when I am relaxing. But I doubt it.

Et bien sûr, merci de ta réactivité et ta gentillesse.

[saul31]

Avec plaisir.

On attend évidemment tes réalisations avec impatience.

[Hellmut]

Héhé merci. Il faudrait déjà que j'actualise un peu mon premier topic avec mes dernières modifs de plaquettes et les customs d'Opinel, je suis un peu en retard de ce côté-là.

[Bigsam]

La vraie bible est là :
viewtopic.php?f=8&t=8510

[aquinatis]

Freddy a fait un superbe WIP.

[Crichon]

Commencé serait plus juste non ?
Y'a de l'idée cela dt.

[freddy1]

je préfère laisser des œuvres inachevées, comme un message pour l'avenir...

[Égée]

je préfère laisser des œuvres inachevées, comme un message pour l'avenir...

[Hellmut]

La vraie bible est là :
http://forum.neoczen.org/viewtopic.php?f=8&t=8510

Argh tu as raison, je l'avais survolé un peu vite suite à la vue de la photo que je pensais représenter
un Rambo-knife planté dans des lasagnes (gore !), un peu comme un Rajah planté dans un jambon sur un de ces DVD que je sais que tu affectionnes.
Et du coup j'avais zappé le reste.
Maintenant j'y vois plus clair et vais me taper le sujet dans son intégralité.
Thanks.