Hand+Ink Letterpress in Aluminum

Intro: Hand+Ink Letterpress in Aluminum

I recently had some time to revisit my mini letterpress project. After using the earlier design for awhile, I wanted to redesign the press to eliminate all 3D printed parts and make it out of metal for increased strength. This press can be made out of MDF or Aluminum with a few quick dimension changes. The files attached are for 5mm thick aluminium sheet. Almost of of the parts can be cut with a laser cutter/waterjet/cnc, although I did use a lathe to make the wood handles and the top cross bar. All dimensions are in mm since I have recently moved to Sweden.

Materials:

For press:
320mm x 290mm x 5mm aluminum sheet
30 mm x 30mm x 300mm block of wood for turning handles
10 Cap nuts - (McMaster source)
1/4"-20 All thread rod
Thin MDF to make printing plates

To print:

Any type of thick paper or card stock, I prefer cotton paper
Printing ink, I tried aqua-LINOPRINT. It dried a bit too fast but was easy to clean up.
Brayer to roll the ink
Acrylic or glass plate to spread the ink

Tools:

Laser cutter
Waterjet/CNC
Lathe
1/4" Allen key

STEP 1: Waterjet Files

Main parts:

Cut the attached DXF file using a water jet. I used 5mm aluminum. If you want to use a different material thickness adjust the inside squares width and height to your new thickness. Remember to space them out correctly to account for the thicker or thinner material.

Cutting aluminum on the water jet is not as accurate as laser cutting MDF. The nozzle shoots out a beam of high pressure water and cutting abrasive and as it hits the material the beam slows down. This creates a taper as the beam cuts through the material. The thicker the material, the more pronounced the taper. The 5mm aluminum had a noticeable taper that required a fair bit of filing and sanding to get the parts to fit together correctly.

The press worked well in MDF. I would suggest cutting out a few extra handle levers and stacking them together for extra strength.

Other parts:

Cut the all thread to roughly 50mm, you will need three of these.

If you have a lathe, turn a small handle that is 50.8mm long and 20mm in diameter. This will be the small front handle.

The larger handle is 160mm long and 28mm in diameter. I used a band saw to cut out the slot for the aluminum lever to fit into. I put the wood handle and aluminum lever together and drilled two holes. Dropped a rivet pin in both holes and peened the ends to hold the two parts together.

STEP 2: Assemble

Once all of the parts are cut out and finished, assembling the press is straight forward. Build the lever system first and then build the frame around it. Tighten all of the cap screws using the appropriate allen key.

I ran into some issues with smooth movement with the aluminum version. It was resolved with a fair bit of sanding and some lubricating oil.

The MDF version should would quite well without much extra work.

STEP 3: Lasercut Printing Plates

You can order professionally made polymer plates for high quality results.

I experimented with laser etching printing plates from MDF. The results were surprisingly good.

Illustrator:

Draw your printing plate design in illustrator. The max impression area is the size a of standard American business card: 2 x 3.5 inches.

Convert all text/strokes to outlines. Copy and paste your design to a new art board and mirror design. This is a very important step. If you forget to mirror your design, text will be backwards when you start printing.

Laser Etch:

The MDF plates were etched on an Epilog Zing 16 Laser. Find a local tech shop so that you can experiment with etching the plates; Luckily I had access to a laser through my university. I ran the raster engraving at 100% power and 60% speed. This was done three times to achieve a depth suitable for printing. I've attached a few sample printing plates you can engrave.

Print:

Use double sided tape to attach the printing plate to the removable aluminum platen - the piece with the small handle.

STEP 4: Print

The key to a good print is in the ink application. Too much ink and it will be heavy and uneven. Too little and it won't fill out.
The results from MDF printing plates were quite crisp. Not as good as a polymer plate but good enough for printing small things for fun. The spark plug card had details that were smaller than a millimeter and it performed well.

STEP 5: Results

With the aluminum press I was able to achieve enough pressure to deboss the paper.

After using the MDF printing plates, pieces of the design fell off under the repeated pressure.

Comments

[lannaneves]

Beautiful! Thanks for sharing!

I've assembled the AI file in SolidWorks, and seems like on the the arms in the lever system is too short - so the aluminum plate doesn't move all the way to the bottom. It's an easy fix though.

[anuska]

Hey! This looks lovely! I would love to see it at work! Would it be too complicated for you to post a video? Or show more detailed photos of the printing process?

[kniegmann]

Working on a video, it should be up sometime next week.

[anuska]

Awesome! Cannot wait!

[kniegmann]

It's up!

[anuska]

Wonderful to see it at work! It really does a fine job! Love the minimalist touch in design and use! Thanks for the video!

[Kdemon]

Can you add a video of the letter press in action?

[kniegmann]

It's up!

[Kdemon]

This is amazing

[kniegmann]

I'm working on it!

[GustavS6]

Looks Great! I live 20 mins from Malmö, and have i tiny little wood-hobby-shop. If you need help with anything wood-related i might be able to help out. Feel free to hit me up!

[kniegmann]

Nice! What kind of stuff are you making?

[GustavS6]

Oh, everything from toolhandles and shop-tools to small furniture, pens and things that i makes the everyday easier.

[AprilH65]

Can the plans be sized up to 4" x 6"?

[saritamarianyc]

Woah! This is so cool.

[DoHop]

I flagged as "incomplete" as I didn't know there is comment; your step #4 has a programming glitch.

Do you sell a parts kit? Or I might commission one?

Beautifully done!

Thank you.

[kniegmann]

All of the files are here on the Instructables so that you can make your own for free!

[DavidH677]

I have etched metal shapes using a low-power laser-cutter designed for wood and card. I spray-painted the metal sheet, etched through the paint with the laser, then etched through the metal chemically, finally cleaning off the paint. This process would make good metal printing plates.

The aluminium squares in this close-up photo are 3.5mm centre-to-centre (but Vector-cut, rather than Raster as you would need for a Plate).

[DoHop]

How precise is the etching?

[DavidH677]

There are several layers to the answer :-)
I've put some detailed points below, but the simplest answer is to look at the image (shrunk by the website). The centrelines of the grid are 3.5mm apart, and the straight edges are not entirely straight. Meanwhile the centrelines of the rings have a radius of 0.4mm. The outer diameter of each ring is roughly a millimetre, and you can see that it's not actually ever so round. The inner circle is a bit over half a millimetre in diameter, and looks even rougher.
BUT to keep perspective, remember that it's actually finer that 300dpi halftone letterpress dots.

1) The POSITION of the etch lines is as good as the resolution of the laser cutter.
2) The WIDTH of bare metal line in the paint is never less than the width of the laser beam, and is more if it's not focused accurately or if the mirrors are dusty. Variations in the thickness of the paint will make small differences in the width of the lines. I'm using a shared cutter that gets hammered 40 hours a week and isn't maintained properly - you could probably do better.
3) The SMOOTHNESS of each etch line is a mixture. Like all Laser cuts, there's always a slight ripple caused by the stepping motion. That is amplified by the way the heat burns the paint - the slightest hesitation and the line becomes a fraction wider. Then there's the bubbling of hydrogen - every tiny bubble slows down etching briefly in one spot until it rises to the surface.Finally, paint is thin and fragile - look hard at my picture and you can see places where the paint has flaked and the line wobbles - especially at corners. Be careful how you wipe bubbles in case you wipe paint.
4) UNDERCUTTING depends on the thickness of the metal - but that's the same for all chemical etching. To give you an idea, this etch is roughly 0.3mm wide by 0.2mm deep.
5) The quality of HALF-ETCHED surfaces depends on the crystalline structure of the metal. You can see that the bottoms of the grooves are pretty uniform and flat, but nothing like as smooth as the un-etched top surface. But this material is work-hardened aluminium, not annealed printing plate.
(Some of this isn't relevant to Letterpress printing, but some folk want to etch for other reasons.)