Thumb print touchmark ? Have

[Albert Botha]

Hi there folks ,im always trying to do the impossible ,to my own frustration most of the times ,but this idea came to me after many thoughts of what i can use as a unique touchmark ,so i thought what if i can use my own thumb print?as a touchmark (Not sure if this can be possible) so the only ppl clever enough to help me find a way ,if there is ,is here on iforgeiron .What about casting it ? Was my first thought ,and in what type of steel ? Melting sping steel maybe ? Any help would be appreciated,maybe there are other ways like machining or lasers that I didn't think of ,cant wait to hear from you ,cheers from South Africa 

[Goods]

Here in the US, if I was really set on the idea, I would get a good ink thumbprint, scan it in, mirror it, then talk an industrial stamp manufacturer to see what the cost would be. There are makers on Esty and other internet sites, but I’m not always sure of how legitimate those “businesses” are. (EDM/CNC work doesn’t normally come in cheap.)

David

[ThomasPowers]

If you are thinking about marking blades, then you might be able to have your cast thumbprint in the guard.  Most blade steels will not cast a great blade. Traditionally you cast an ingot and forged it to shape to refine the large grains left from casting. Forging will destroy the fine details of the casting.

The simplest method would be to apply a resist with your thumb and then  etch the area, plasticine clay can be used to make a small dam to hold the etchant.  I would sugest ferric chloride. 

A slightly fancier method, photo etching, uses a resist that you cure with UV light and so you can place a desgn over it printed on a clear plastic sheet and expose it to UV and wash off the unexposed resit and then etch.

Electro etching uses a stencil a power supply and an conductive fluid.

Laser etching/engraving works well.

You could even engrave it onto your metal.

Note that most of these methods take skills and equipment and will raise the cost a bit!

I went to college with a fellow who's body chemistry was *very* corrosive.  He once demonstrated by taking one of the *very* stainless, stainless steel spoons from the cafeteria and sticking his thumb on the bowl and leaving it 24 hours whereupon his thumbprint couldn't be washed off!

[Albert Botha]

Maybe i should have added that i want to use it to mark my art,knives and items i forge.

[JHCC]

As ThomasPowers notes above, electrolytic etching is worth a try; the method is detailed elsewhere on IFI (e.g., HERE and HERE). If I were attempting a thumbprint, here's what I would do:

1. Create an image file of your thumbprint on your computer. Edit the image so that it's (a) the size you want, (b) halftone (black and white only, no gray), and (c) a mirror image of the original.
2. Print that image with a laser printer on glossy inkjet paper. The laser toner will transfer to the paper, but it won't bond to it.
3. Clean your workpiece thoroughly.
4. Place the printed paper on the workpiece, image side down.
5. With a hot iron, press the paper against the workpiece. This should melt the toner so that it transfers to the workpiece.
6. Soak the paper with hot water to soften, and peel back gently. This should leave the toner image behind.
7. Proceed with etching.

Remember that the stencil acts as a negative; that is, where the image is black, the workpiece will not be etched, and where the image is white, the workpiece will be etched. If you want the lines of your print to be etched into the blade, you might want to edit the stencil image to be a negative of the original thumbprint.

Hope this helps.

[Glenn]

You may want to reduce the number of lines in the fingerprint to it still looks like a fingerprint but is much easier to work with.

[JHCC]

Pressing your thumb against the red-hot metal is NOT recommended, as this is more likely to remove the print from your thumb than it is to impress it into the workpiece.

[Albert Botha]

9 minutes ago, JHCC said:

As ThomasPowers notes above, electrolytic etching is worth a try; the method is detailed elsewhere on IFI (e.g., HERE and HERE). If I were attempting a thumbprint, here's what I would do:

1. Create an image file of your thumbprint on your computer. Edit the image so that it's (a) the size you want, (b) halftone (black and white only, no gray), and (c) a mirror image of the original.
2. Print that image with a laser printer on glossy inkjet paper. The laser toner will transfer to the paper, but it won't bond to it.
3. Clean your workpiece thoroughly.
4. Place the printed paper on the workpiece, image side down.
5. With a hot iron, press the paper against the workpiece. This should melt the toner so that it transfers to the workpiece.
6. Soak the paper with hot water to soften, and peel back gently. This should leave the toner image behind.
7. Proceed with etching.

Remember that the stencil acts as a negative; that is, where the image is black, the workpiece will not be etched, and where the image is white, the workpiece will be etched. If you want the lines of your print to be etched into the blade, you might want to edit the stencil image to be a negative of the original thumbprint.

Hope this helps.

"Saved" thank you very much.

5 minutes ago, JHCC said:

Pressing your thumb against the red-hot metal is NOT recommended, as this is more likely to remove the print from your thumb than it is to impress it into the workpiece.

This my second plan ,i had doubts thou.

[Irondragon Forge ClayWorks]

I wouldn't want to have my thumb print on anything that could be used in the commission of a crime.

[ThomasPowers]

Any item that is unique and custom made should not be used in the commission of a crime----"Hand Forged Hatchet,  My Logo, #345"---"I sold that to Alferd Packer as he needed one for a trek he's going on in the Mountains..."

[Albert Botha]

On 8/26/2021 at 3:51 PM, ThomasPowers said:

If you are thinking about marking blades, then you might be able to have your cast thumbprint in the guard.  Most blade steels will not cast a great blade.

Most blade steels wil not cast a great blade ,interesting ,care to explain a bit or point me in the direction to read about this?

On 8/26/2021 at 5:00 PM, Glenn said:

You may want to reduce the number of lines in the fingerprint so it still looks like a fingerprint but is much easier to work with.

Noted ,thanks! 

[JHCC]

To cast something, you have to melt the metal first. Melting down knife steel can mess up the carbon content. It also takes a lot more energy to melt steel than it does to melt copper or bronze. 

Come to think of it, I don’t think anyone ever casts steel knives (although Bronze Age blades were often cast); I believe the grain structure has too much porosity. 

[George N. M.]

John, I have seen late 19th and early 20th century tools marked "cast steel."  I particularly recall an axe.  I believe that cast steel is still used for certain complex shaped machine parts.

"By hammer and hand all arts do stand."

[JHCC]

The “cast steel” of those tools doesn’t mean that it was cast to shape, but (if memory serves) that it was Bessemer-process steel rather than crucible steel. 

As for complex machine parts, even these would not be cast to their final size and shape, but would still require some degree of machining. I’m guessing that any company doing that kind of industrial production would be in a much better position to control alloy content, heat treatment, etc than a one- or two-person shop. 

[Frosty]

While there are a number of etch methods that will produce detailed designs and I don't have anything significant to add to what's already been suggested. If I were doing this level detail in a touchmark or logo in any quantity I'd bite the bullet and buy a CNC laser etcher cutter. I'm seeing them on Amazon starting around $200 and up, WAY up. 

As described above make an ink on paper finger print, scan it and convert the scan to the file type used by the laser etcher, adjust for size, detail, etc. and save of course. 

There are also 3D printers that will etch, "Glow Forge," is a name that comes to mind, I see ads on TV frequently. One of the high end bladesmiths on IFI regularly laser prints patterns to cast furniture for his blades. 

Frosty The Lucky. 

[ThomasPowers]

(John, backwards!) "Crucible steel" was the first cast steel and in the West is associated with Huntsman in the 1700's. Bessemer was in the 1850's. (So Robin Hood was NOT casting steel arrowheads!)  It was a great step forward from blister and shear steels as it did not contain the ferrous silicates of the wrought iron derrived steels and was much more homogenious in carbon and alloy contents.  HOWEVER when you cast items you either get stresses and cracking from thin areas chilling too fast and fat areas still being liquid or you cast a large cross sectional area and get large weak grains from cooling slowly---the way they dealt with large grains was to do substantial forging AFTER an "ingot" was cast and so reduce the grain size through the forging.  When tools are marked Cast Steel they were made from a cast steel ingot that was then forged into the item.  In Sheffiend England they were still "teeming" cast steel into the 1920's!   

Modern processes and alloys can avoid a lot of the issues earier cast steels had; but you may notice that "forged" items are still generally used when strength is paramount.

If you really want to gain some background in this may I commend to your attention: "Steelmaking before Bessemer: Vol I Blister Steel and Vol II Crucible Steel".

Now Wootz and other crucible steels were know in Central Asia 1000 years earlier; but not much made it to Europe save a few blades.  ("Crucible steel in Central Asia: production, use and origins"  PhD Thesis of Dr A Feuerbach, Online at UCL Discovery)

[JHCC]

Right; sorry. Thanks!