Hot Foil Printing Dies (March 2022)
I've been out sourcing printing
dies but the lead-time was getting ridiculous especially when the dies
are so easily damaged.
The cost wasn't so much of an issue but waiting for new dies could set
production back a month or more.
I already produce the artwork and have experience with CNC machines and
programming; not that you need much these days as the software pretty
much produces the program for you, but a knowledge certainly helps when
you need to tweak things.
I could use my Bridgeport milling machine which I converted to CNC some
time ago, and I've done so in the past, but when using 0.2 diameter
cutters the speed of a Bridgeport is too low at only 3000 rpm max . I
could attach a high speed spindle but you have to remember these dies
are only 25mm x 12mm so the text is only 1.5mm height, so its a big
heavy machine for very fine work.
I decided to buy one of the cheap desktop CNC machines off eBay.
The software I use is Vectric Aspire. It does take some time to learn
and has some strange ways of doing things when coming from an AutoCAD
background, but it is a very powerful program which produces amazing
results.
The other issue is cutter selection. Over the years I've been through so
many engraving style cutters with varying results.
What I use is single flute 45 degree included angle with 0.1mm tip flat.
My advise is don't always believe the description on eBay as some
suppliers descriptions are very misleading.
If machine plastics you can get away with a smaller inclusing angle but
I've found with brass an the fine details being machined that these tend
to break very easily.
It does mean you have to adjust the spacing between elements to allow
the 45 degree cutter to produce the detail. Luckily in Aspire you can
adjust the space beteeen individual text letters easily.
Artwork produced in Vectric Aspire (LEFT) with simulation outpiut (Right)
Tool Path
Desktop CNC Setup
The finished print die. Not belwo that they are designed to print on a curved surface
A selection of finished dies
The printed item