Reproduction de médaille

Bonjour,
J'ai trouvé un établissement qui peut reproduire en laiton les médailles des fabricants.
Seul petit problème, la copie a un diamètre d'un bon millimètre en moins.
A part cela, le travail est très précis et soigné.
Il s'agit des établissement POURSIN, 35, rue des Vinaigriers, 75010 Paris. Téléphone : 01.46.07.17.07
http://www.poursin-paris.fr/
Les tarifs : 50€ HT pour la fabrication du moule qui peut servir à la reproduction d'autant de médailles que l'on veut. Ensuite, il faut compter 18,40€ HT par médaille.
Bien sûr, il faut avoir un original à confier à ce fondeur et il le rend une fois le moule fabriqué.
Personnellement, j'ai fait reproduire une médaille Alexandre de 50mm de diamètre, le mm manquant se voir à peine, il suffira peut-être de remplir l'interstice avec de la gomme laque ou autre chose.
Cordialement,
Jean-François

Voilà qui intéressera forcément nos amis restaurateurs.
Dans le même genre, quelqu'un aurait-il l'adresse d'un fabriquant/graveur de porcelaines?

Je constate que le dépeceur d'harmonium qui sévit sur eBay continue, et qu'il propose à la vente une médaille Alexandre identique à celles qu'on peut se procurer en copie ci-dessus au prix mirobolant de 90€ !!!
Je fais donc remonter ce sujet, afin que ceux qui ont besoin d'une telle médaille 1) ne rentabilisent pas ce triste sire, 2) ne se fassent pas plumer alors qu'ils peuvent acquérir le même article pour 20€ sans avoir la mort d'un bel Alexandre sur la conscience !

Hi

Back on the old days in my previous profession we made metal castings (dentures, gold crowns, metal bridges etc.) for dental purposes.
This kind of medal is quite easy to reporduce e.g using extra hard molding plaster and mold silicone. It keeps original dimensions very accurately and all fine details are copied. Then just spray with bronze and maybe fine layer of clear lacquer. Of course if you drop it it will break but it is much more easier to make than casting with actual bronze. Should be 30min's job if everything goes as in movies.
I have 2 medals that can be removed from Alexandre's one from pre 1900 and post 1900 diameter of ~50mm. If some one is interested I could ask if I'm able to visit my old "office" for experimental purposes. Last time when I visited there I cleaned one ivory keyboard from mouse pee using dentist tools and chemicals .

Of course this can be done also from plastic but it will be pink....... and it's difficult to clean afterwards to have smooth surface.

Best Regards Jaakko

Hello Mathieu,

And the crazy man was asking even more for the same medal, as you can see in this expired ad:
http://cgi.ebay.fr/HARMONIUM-ALEXANDRE-MEDAILLE-ANCIENNE-/330786870257?pt=FR_YO_InstrumentsMusique_PianosClaviers_Pianos&hash=item4d046f13f1&clk_rvr_id=385748343876#ht_800wt_1344

I wish you luck,

Dib

If you hae a process to remove the yellow colour due to mice pee on ivories, I'm very interested, Jaakko !!

Hi Mathieu

I don't recall anymore ( it has been some years ago) what was the name of the solution but anyway too expensive for hobbyist to use. Date of last usage was expired so it was going to be placed into trash anyway why not into keyboard .
I used very fine sandpaper, rubber grinding disks and "Dremel" actually Kavo K9 handpiece then some compound that contained hydrogen peroxide and grinding particles. Finally I polished those with pumice+water and rotating brush. Then with polishing wax and cloth brush to get smooth feel. Tools were dental tools that are used for polishing plastic, metal and porcelain.

By the way... pumice and water is excellent to be used to polish metal parts in actions from rust. You'll get showroom shine with one treatment.... And if that's not enough then use rotating cloth brush and some polishing wax. Just hook brushes to power drill and enjoy.

There are some "home made" mixtures of baking soda and hydrogen peroxide e.g 10 milliliters of hydrogen peroxide into 15 milliliters of baking soda. This should create "paste" that you could brush manually or with Dremel into keys. Try to avoid wetting of ivory as it curls and might come off. I haven't tried this but if you have extra keys that you could test please share results among others if that works.

Other instruments and tools from "denture" world are also quite good in harmonium repair hobby. For example hide glue pot made from denture pressure cooker. Most accurate thermostat in world and timer. I'll never forget kettle ON more than 1h at time.



Best Regards Jaakko

Hi Mathieu

I got bored and started to surf in web about ivory whitening and came across to this page:
http://piano.about.com/od/pianomaintenancerepairs/a/whiten_keys.htm

In principle similar way as hydrogen peroxide and brushing, but that milk part was new to me

And then elsewhere in web:

Put a little lemon juice on a lint-free cloth and gently rub the keys. Clean out the lemon juice soon afterwards with a cloth dampened with water.
Hire a professional restorer. These people can use a mixture of hydrogen peroxide, which will remove all yellowing, but should not be attempted by an amateur.

So hydrogen peroxide and baking soda it is...... I found old keyboard where to try this when I have time. But let us know if you tried this before me.

Best Regards Jaakko

Well, thank you !

I knew of the recepies with hydrogen peroxide and baking soda, but I'm not sure it will work in the case I think. It has probably already been attempted.
And anyway, it's not on the list of 'to-do" things before long !

Merci !
Je connaissais déjà les recettes à base de peroxyde d'hydrogène (dont la solution donne l'eau oxygénée) et de bicarbonate de soude, mais je pense que le précédent intervenant sur le clavier qui j'ai en tête aura déjà essayé.
Quoi qu'il en soit, la position de ce clavier dans la liste des choses à faire est assez lointaine !

Bonsoir, ayant besoin de médailles "Alexandre" comme beaucoup de collectionneurs, je pense; j'ai contacté ces Ets Poursin. Ils existent toujours ! Par contre ils n'ont plus le moule dont il est question, donc il faudrait donc reprendre le processus à zéro. Je vais essayer ailleurs.