A Study in Embossing

[JohnBarton]

Here is a study in embossing. For this one we did a celtic knot stamp in acrylic using the laser and stamped it more than 48 times using the die press.

We found that embossing, especially at this level, is not as easy as one might think. When you see a case that has embossed leather on it then it's usually referring to leather that was done with a large plate on a large press or run through really big rollers to impress the design on the leather making it like fabric.

This case was done more like a hand tooled case in that the stamps are 50cm squares and we placed each one carefully - one screw up and the leather piece would be ruined. Not good when you are making a 5 ton press do the impressions and you have to place the stamp 48 times perfectly. So the embossing is carefully arranged. For this one we deliberately left the seam area unstamped to show off that it was not done on a large plate.

Anyway, enough chatter, this was a custom job we did for GTF Cases and I am very proud of how it turned out.

[scottishshoemaker]

That's really nice, now where do I get an embossing machine that'll fit in my 6'x4 shed?

[CampbellRandall]

Very nice work. I can see how tedious it could be using a small press.

For production work, companies use a plate embossing press (over 100 tons) for large pieces,

Model P140 Hydraulic Plate Embossing Press

or a rotary embossing machine, like the model R32 which can handle material about 8" wide.

Model R-32 Rotary Embossing Machine

[Storm]

Your best yet! The construction is immaculate in its conception!

[JohnBarton]

Very nice work. I can see how tedious it could be using a small press.

For production work, companies use a plate embossing press (over 100 tons) for large pieces,

Model P140 Hydraulic Plate Embossing Press

or a rotary embossing machine, like the model R32 which can handle material about 8" wide.

Model R-32 Rotary Embossing Machine

We used a small hydraulic die press that was a factory cast off. The controls are broken but we can make it work with a screwdriver. So we decided to start playing around with embossing designs. Initially we did some larger plates for another line of Pirate Themed cases done for another customer. Those we did out of some sort of linen based material which worked well. Interestingly when we took the larger plates to the local factory and used their large die press the result wasn't as nice and crisp as when we used our small press.

At this point I should mention that I am completely and utterly ignorant of how hydraulic die presses really work. We know press the button it goes down - release the button it goes up. We have blocks of granite to use to raise or lower the material to increase the pressure (at least that is our theory of what is happening) We just figured that we had this machine and wanted to see what we could do with it.

I have seen larger rotary presses at the big machine show they have here each year. While they didn't say that they could be used for leather I assume that they could be or be modified to work with leather.

At the leather market here it seems as though a lot of the leather uses plates or tiles and they use a hydraulic press. I can often see the misalignment clearly. But since most of the leather they sell at the market I go to is destined for handbags I guess it doesn't matter much if there are errors in the alignment since the actual cut pieces are likely to be fairly small.

This is quite fun to play with. To do these stamps took us two days of trial and error to get them right in terms of what part should be raised, how big the pieces should be, how to align them, which material will work etc... There is a lot that can be be done playing with positive and negative space. I can see a lot of fun in making some really cool stamps and combining them. Leather is such a great medium to work in because you can do so much with it.

[JohnBarton]

Also I don't want this to be confused with the embossing done by Silva Fox or Clay Banyan among others. I wish that there were other terms for either of these methods because what Silva and Clay do is genius and far and away more artistic than this type of machine assisted work.

For those of you who don't know the Silva Fox type of embossing is done where one molds (sculpts) the leather from the back side and then fills the cavities with a filler that hardens. We do this as well on some cases but no where near the level of the two I mentioned. (yet)

[KRLeather]

That is a beautiful case, I would LOVE to make something that good. You must be very pleased with the result!!

K

[KenE]

I was experimenting with some celtic stamps myself. I took an image and with some help from a co-worker (i.e. at my day job) we made a stamp on an engraving machine. We were quickly finding the limitations of trying to make the stamp using the engraver software. What type of CAD/CAM program did you use? Is the stamp made from a rapid prototype machine?