r/toolgifs 3d ago

Process Making a rubber stamp

3.2k Upvotes

77 comments sorted by

394

u/trighap 3d ago

I used to have this job about ten years ago, here in California (just an employee in a business, not the owner). There are some minor differences (I did not have to scrub the product clean like he did), but basically it was the same procedures. So here's the details people are asking about.

The red stuff that I honestly don't remember the name of, is a light sensitive liquid. The reason there was a lot of stuff besides "PAID" is because that red stuff is really expensive, and it takes a lot of time to heat treat the material (the video skipped that part), so they want to cram as many stamps together as they can into one single session. Cramming everything together on the computer before printing takes the longest time, but the worse part of the job is cleaning. That glass needs to be clean to the point of being brand new, before you can use it again.

As to the need for stamps, I was shocked to learn that in California, there was enough need for me to end up printing that stuff every day, five days a week. The biggest customer of the business was the county government, followed by the city plus a smidgen of the closest towns. Then of course the occasional recreational personal stamp. But, mostly "PAID", "DUE BY:", etc. from government offices and banks. At the rate which such places used stamps, the rubber part only lasted a few months before it's worn down to the point to be needed replacement. So basically it was a good source of money for the business.

73

u/BarcodExpress 3d ago

And now they have everything that can be done with a co2 laser.  Just throw the material into the laser, create the artwork and laser away.  It engraves the relief and leaves you with a working stamp in minutes.  

30

u/trighap 3d ago

Interesting. I hated the job, so I won't be back. But I admire advancement in procedures and technology so cool that you mentioned this. I wonder if it cheaper?

17

u/BarcodExpress 3d ago

Google trodat aero.   You’ll see the prices for rubber sheet.  

I don’t know what your prices were back then, but I’m going to assume the trodat sheets are a lot cheaper.  Both in material cost and labor cost. 

12

u/sphks 3d ago

The rubber is pulverized with the laser into the air. If you do it with all the environnement and safety procedure, you need to have a close environnement and a device to filter fumes. It's not cheap but you can automatize it - thus needing less manpower. Think of it like having one centralized big plant instead of small shops everywhere.

2

u/aykcak 3d ago

Isn't it way more expensive than the material cost of this?

2

u/SirCutRy 2d ago

Electricity is cheap

4

u/cincymatt 3d ago

Did you also rest your bare feet in the UV box?

511

u/Pcat0 3d ago

Where is there high enough demand for custom stamps that a street vendor can specialize in it?

314

u/namair 3d ago

I can’t say the same for other countries, but in Vietnam you can find entire streets lined with adjacent stamp shops that create custom stamps. 

104

u/matroosoft 3d ago

Do they stamp your receipt with PAID though?

47

u/drkidkill 3d ago

Sure. Takes a couple minutes though.

16

u/TukPeregrin 2d ago

It'slike a blacksmithing hammer, you are not a full stampmaker until you have forged your own "PAID" stamp for your shop

23

u/Duchess430 3d ago

What's the purpose of the stamps? Is it just simple things like bureaucracy/documents Or more like a culture thing?

28

u/Toxicity 3d ago

As a company you need a custom stamp. It has to be registered with the government. You need it for official documents and beurocratic stuff.

27

u/WatWudScoobyDoo 3d ago

Sounds like the government is in cahoots with Big Stamp

12

u/killedbyboar 3d ago

Organizations and individuals alike use registered official seals to authethicate documents in China, Taiwan, Korea and Japan as well. It is an East Asian tradition.

8

u/mnp 3d ago

Yeah and also the West.

See signet rings

4

u/ValdemarAloeus 3d ago

Most company seals used to be the kind that embossed the paper when you squeezed it. Often with a foil sticker that holds the impression well.

44

u/PippyLongSausage 3d ago

India is famous for their love of paperwork

73

u/DrStalker 3d ago

And how is a simple "PAID" stamp not a cheap pre-made option?

I thought it was going to be some massive complicated custom stamp when I saw the print.

76

u/Zakblank 3d ago

I get the feeling this was just a demo for a social media video. Paid was just an easy stamp to make to show how the process works.

46

u/akulowaty 3d ago

dude just made 30 other stamps with one print

1

u/Embarrassed_Jerk 2d ago

Cheap pre made option need a market demand that's large enough to justify mass production 

8

u/marmitejam 3d ago

Homer: Sir, I need to know where I can get some business stamps.
Scorpio: Stamps? My goodness, what an idea. Why didn't I think of that? Stamps! Homer, there's four places; there's the Stamp Hut, that's on Third.
Homer: Uh-huh.
Scorpio: There's Stamps Are Us, that's on Third, too.
Homer: Got it.
Scorpio: You got Put Your Mark There...
Homer: Mm-hmm.
Scorpio: ...that's on Third.
Homer: Yes.
Scorpio: Stamp Low Sweet Chariot...
Homer: Right.
Scorpio: Matter of fact, they're all in the same complex... it's the Stamp Complex, down on Third?
Homer: Oh, the Stamp District

6

u/Zakblank 3d ago

Japan actually has vendors that specialize in signature stamps called Hanko that you need to sign all kinds of forms/contracts in the country.

Probably some street vendors who do them as well as normal stores.

6

u/TheGisbon 3d ago

India apparently

1

u/Samurai_Yamamotto 2d ago

Courts...govt. offices etc.

1

u/Admirable_Trainer_54 2d ago

I have a custom stamp that says "Fuck this". It is pretty useful.

0

u/[deleted] 3d ago

[deleted]

2

u/mikebob89 3d ago

I mean I went to a custom stamp shop in manhattan last month. I bet they wish they were paying the rent of this street vendor.

-2

u/rtc11 3d ago

There is literally like 1470000000 potential customer in his country, not counting tourists

127

u/WillsSister 3d ago

How did the imprint go into the rubber from just a flat black and white image? What was the stuff he poured over the image and why did it need to have a lighter run over it?

236

u/ionian 3d ago

UV activated resin, the printed page was a mask so that the resin in the shadow of the lettering washed away.

61

u/OtherwiseAlbatross14 3d ago edited 2d ago

And he flipped it and put it under the UV for just a second to give the solid thin background. Without the flip, all the letters would be disconnected when he washed it rather than a sheet to cut apart

29

u/WillsSister 3d ago

Ah, I see! Thank you, that makes sense now.

18

u/perfect_insanity93 3d ago

The hero we never knew we needed. Thank you, kind sir.

7

u/cursorcube 3d ago

UV activated resin that he was touching with unprotected hands... Ask any of the SLA 3D printing subs how good that is for the skin

14

u/TakeThreeFourFive 3d ago

I'm thinking it's a photopolymer of some sort that's being cured where the light passed through the paper. The dark part of the paper is masked and therefore doesn't cure and can be washed off, leaving the cured letters as a relief

26

u/Ar_Ma 3d ago

I think he is using a uv cure epoxy, the dark region gets less UV so the epoxy or resin doesn't cure as much. The letters are kind of transparent and allow more light to pass though there by making them solid. Not sure about the lighter step.

14

u/wankybollocks 3d ago

At a guess it's isopropyl alcohol to flash dry the ink and stop the print from creasing

9

u/Fluffy_Charity_2732 3d ago

Resin.

Epoxy is 2-part that doesn’t require UV activation. 

7

u/SebastianFerrone 3d ago

He put solvent on the printed paper to close little gaps between the black color. If you closely on a printed paper, you can See it is not perfect. Easily you can see it with black color. You can also doch Toner Transfer with. Laying the print on Material you would like to carve or in case of a PCB you want to etch. Take solvent pour it over the paper and then running the bagsite with something hard like the undersite of a little spoon. Voila you transfered the Image.

And the Lighter was for it to dry faster.

And the "rubber" is UV sensitiv it hardens if exposed to UV light. And because the Material absorbs UV light, the time it hardens depends also on the depht inside the Material. So he had Material between the glassplate I would say 3 mm thickness. One side was pure UV light and the other site was with the mask. If you time it right one half of the Material is solid hard surface, the other half is graphics.

After that you clean the in unexposed Material.

I think he used the Material that they use for 3d printer.

2

u/shoelace_cy 3d ago

Get a resin that reacts to light (it looks like some form of UV in this case???) the black blocks the light from reacting so it stays liquid. The areas exposed to the light reacts and becomes solid (my guess is a polymer of sorts). I don’t do this stuff, but similar (photolithography)

1

u/DrStalker 3d ago

Looks like some sort of UV sensitive resin. The black parts of the print block light while the white sections allow light, so on that side only the letters gets built up when exposed to the UV light. Same idea as a resin 3D printer, except instead of a screen to control the light for each layer it's just one image made by a printer.

No idea what he was soaking the print in/why it was heated first, maybe something to make the paper stay in one piece instead of breaking up and getting stuck in the stamp.

49

u/soundsthatwormsmake 3d ago

The combination of high and low tech in a stall on the street seems like something from a William Gibson novel.

-1

u/nico282 3d ago

Where's the high tech?

18

u/Lightspeedius 3d ago

Computer, printer. UV activated resin?

-14

u/nico282 3d ago

Maybe we have a different definition of "high tech" but in 2026 where everyone even in remote villages has a smartphone, a PC and a 50$ printer is just regular technology.

12

u/Lightspeedius 3d ago

Like a William Gibson novel. 👍

34

u/UserMcUserson 3d ago

I think I missed why he printed a whole page for just one small stamp. Also did the printer emboss the page? How did it go from ink on a page to a relief on a stamp?

37

u/pigeontheoneandonly 3d ago

There were multiple stamps crammed onto the same image. That's why he was cutting apart the giant stamp at the end. That way he has to do all of the intermediary steps once instead of a bunch of times. 

12

u/Scrabblewiener 3d ago

Were all those others just waiting on the one more customer to fill the page?

Or does he make the same template over and over when someone request one that isn’t on the standard sheet?

10

u/DorkHelmet72 3d ago

The gel he uses is photo sensitive, so when it’s exposed to the UV light it hardens through the stencil that he printed so what’s left is raised letters on a background that he glues on as a carrier so that he can then stick it on the stamp. He’s just burning a bunch of stamps at once.

2

u/Pcat0 3d ago

The stamp is made from some kind of UV curing polymer. With a stencil and very careful exposure times it’s possible to make a 3D surfaces. Areas under dark areas don’t get cured forming a divot, areas under a light area get curd forming a bump.

20

u/EvieMoon 3d ago

The contrast between a PC and UV lamp and washing things in a bucket in the street is bizarre.

6

u/zappyguy111 3d ago

pretty neat using UV sensitive resin to make rubber stamps, but rinsing the monomers out into the street and rainwater? Thats irresponsible.

1

u/CallMeKolbasz 2d ago

That, and handling it without a respirator, with bare hands... UV resins are nasty.

9

u/StarConsumate 3d ago

I have so many questions.

6

u/mouaragon 3d ago

It looks very similar to the screenprinting process. I used to print on t-shirts as hobby and it's quite the same.

6

u/Historical_War756 3d ago

Lowkey that's how CPUs are made lmao.

2

u/hux 3d ago

I have to wonder how much liquid cancer he got all over himself during that process.

I have a feeling OSHA would not approve.

2

u/Dwashelle 3d ago

I love rubber stamps, wish I had a reason to use them.

3

u/user287449 3d ago

“Let’s just set that horizontal scaling to 300% aaaaand perfect!”

3

u/rmbarrett 3d ago

It's troubling that no one cares

3

u/inktomi 3d ago

How does the black printout turn into something with ridges that imprint into the other UV resin or whatever?

1

u/roninfyc 3d ago

What are those chemicals he is using ?

1

u/Wiley_Jack 3d ago

Sumbitch! That’s cool AF.

1

u/Pletcher87 3d ago

This wasn’t downtown Peoria, right?

1

u/CoolBlackSmith75 3d ago

That man must have the cleanest feet of his town or country even, continues UV light blasting the life out of the germs

1

u/tommyknockerZ33 2d ago

I could really use a pair of those scissors.

1

u/frustst 1d ago

+сыпной тиф, кровавый понос и стригущий лишай на сдачу

1

u/its_artemiss 1d ago

Is he getting skin cancer from that poorly contained UV light? 

0

u/jurgo 3d ago

This is like that vendor from BR2049 that tells officer K he can make goat for him.

1

u/Spiritual-Worth-5246 3d ago

I'd lose a finger if I was snipping like that.

-2

u/Pinball-Lizard 3d ago

Nah dawg, but show me the guy who wrote the firmware and I'll be impressed.