Share this project


Share this project

Realise your K40 laser's potential with open software for productivity and upgraded hardware for enhanced engraving and cutting quality
Realise your K40 laser's potential with open software for productivity and upgraded hardware for enhanced engraving and cutting quality
168 backers pledged AU$ 22,075 to help bring this project to life.
Last updated


Gerbil: The Open upgrade for your K40 Laser project video thumbnail
Replay with sound
Play with

Gerbil: The Open upgrade for your K40 Laser

AU$ 22,075


What is a prototype?

A prototype is a preliminary model of something. Projects that offer physical products need to show backers documentation of a working prototype. This gallery features photos, videos, and other visual documentation that will give backers a sense of what’s been accomplished so far and what’s left to do. Though the development process can vary for each project, these are the stages we typically see:

Proof of Concept

Explorations that test ideas and functionality.

Functional Prototype

Demonstrates the functionality of the final product, but looks different.

Appearance Prototype

Looks like the final product, but is not functional.

Design Prototype

Appearance and function match the final product, but is made with different manufacturing methods.

Production Prototype

Appearance, function, and manufacturing methods match the final product.

Project supporting material callout image

Prototype Gallery

These photos and videos provide a detailed look at this project’s development.

What or who is Gerbil?  

This Kickstarter project upgrades the popular K40 laser cutter/engraver. If you don't already own a K40, go buy one on eBay of similar - they're now really affordable, starting at around $250 USD.

  • Extremely easy, just import a picture in Inkscape and engrave or cut (no manipulation effort)
  • 16 bits PWM, 380DPI resolution engraving (enabling max. resolution of stock laser), not a stock Arduino but bespoke design
  • Keeps the CO2 Tube energized during engraving, so better quality engraving and longer life span of the laser tube
  • Just plug and play, all the hard work has been done by us
  • and ... it is Open source!

Gerbil is a small device to make your K40 laser cutter/etcher more user-friendly and improve the output quality.  It can be installed into your K40 with a minimum of fuss, and at last, you can realise your K40's potential to easily produce quality laser cuts and beautiful engravings. Instead of clunky proprietary software, you can now use any software produces G-code output.  We've enhanced the popular (and free !) Inkscape so you'll be getting the most out of your laser cutter/engraver in no time without the trial and error approach.

By supporting this project, you'll not only be getting great hardware at a great price, you'll be releasing a robust G-code software solution into the open source community, so we can all benefit from further improvements. We will monitor the community feature requests, and will jump in and help out when we can. For example: include a g-code sender within the plugins.

Setting up your Gerbil's new home  

Simply turn off your K40 at the powerpoint, disconnect your existing controller, and plug in your Gerbil.  Grab a screwdriver to re-position the end-stop.  That's the hardware done.  On your PC/Mac, install Inkscape and the plugin/extension, and you're ready to go.  

How does Gerbil communicate? 

Gerbil connects to your PC or MAC via a USB connection.

What's so special about Gerbil? 

Some engravings produced
Some engravings produced



Gyrfalcon engraving
Gyrfalcon engraving


Photo engraving (1/4 of A4)
Photo engraving (1/4 of A4)


Photo engraving (A4)
Photo engraving (A4)
Easily produce from plastics and leather
Easily produce from plastics and leather



Any laser cutter/engraver requires you to experiment with hundreds of permutations of settings and image manipulation to achieve an acceptable result with a lot of wasted material in the process.  But with Gerbil, the plugins and firmware will help you create a great result first time.  

 project video thumbnail
Replay with sound
Play with

For you tinkerers out there, don't worry - you can still optimize, configure and experiment with picture settings (in the movie above, F-Feedrate, S-Laser strength, Receive-Data buffering settings in the g-code sender). Gerbil engraves with 256 Grey levels in a very laser small range (2mA of 20mA range) and beyond if you want to carve the wood or work piece even deeper to make your images really pop out.  Additionally, Gerbil excels at cutting with different power settings and any repeat cycles. 

 project video thumbnail
Replay with sound
Play with

Is Gerbil safe?

Gerbil includes sensible features to increase the safety of your Laser Cutter.  The laser is automatically turned off when the K40's carriage or motors stop moving. If you choose to install the optional pause, resume and abort buttons, you will be able to safely adjust or inspect the work piece during the cutting or engraving process.

Can it drive other Lasers?

Well depends on the hardware and how tech savvy you are. I bought this 18 year old Trotec laser (75 watt Synrad excited RF laser) for $250 on eBay (postage another 250) and removed its dead controller (size of a old pc motherboard). 

Old vs New controller (below/right corner)
Old vs New controller (below/right corner)

Replaced the dc motors/encoders with just simple of the shelf NEMA17 stepper motors that I had laying around. The existing mechanical end stops could be re-purposed. All with all took me under 2 hours. And now I have a big massive working laser, hurrah!

What else is included?  

All rewards include:

- End stop flag and 90 degree conversion bracket

- Access to the enhanced Inkscape/Gerbil software plugins

Rewards in a nutshell
Rewards in a nutshell

What additional accessories can I get for Gerbil?  

For the best possible results, consider the 'pro-pack' reward, which includes:

- a small drag chain to feed the K40's air assist or electric fan cable

- a high quality laser lens to concentrate the laser into a smaller area, resulting in sharper engravings and improved grayscale spectrum

Where was Gerbil conceived?

The journey began over a year ago when I purchased a Chinese K40 Laser cutter and engraver from eBay. I quickly discovered that the Chinese proprietary software and dongle were unusable, especially as it came without instructions.

Fortunately I had some knowledge of the open source CNC motion firmware 'Grbl', and it turned out to be very suitable for controlling the K40 with some software modifications. 

Success factors:

  • Well thought through open source tool-chain: Be productive, less waste!
  • High resolution steppers for precision cuts
  • 16 bit PWM to perform 10 bit engraving (380 DPI picture engraving)
  • Keeping the laser ionized during engraving (enhances quality and expands life span of the tube)
  • Easy Plug-and-play solution
  • Safety features
  • Cost effective

Also seen at


Gerbil's website with lots of information
Gerbil's website with lots of information


Bay Area Makerfaire 2017
Bay Area Makerfaire 2017




The technical development

The Gerbil controller
The Gerbil controller


Starting out with a basic Arduino board (which is an 'Open-source electronic prototyping platform enabling users to create interactive electronic objects') and a simple Arduino motor shield, I found it worked really well for cutting wood and acrylic but the engraving results were unsatisfactory. I realized that more resolution, shades of grey, and depth were needed for high quality engravings. Finding another Atmel processor, one with two additional 16 bit counters, allowed for a proper grey scale range in the very narrow laser power band suitable for engraving, while still allowing full power for cutting.

To be able to use the hardware enhancements, I re-wrote the raster Inkscape plugin to generate a matching high resolution raster in g-code format and configured the right settings in the controller's firmware to generate the laser output pulses. After testing 64 combinations of frequency, speed and power within the controller firmware, the winning combination of contrast, depth, grey shades and resolution for the engraving was found !

The next barrier was the wire connectivity between the machine and the controller. K40 machines use a combination of hard to find connectors. Also, there are slightly different K40 models on the market so I needed to cater for these combinations. Sourcing these rare connectors at a reasonable price was like looking for a needle in a haystack. 

The next requirement was to ensure the installation process is easy for non-experts. That means swapping connectors and installing open source software like inkscape on your PC. The controller connects to PC via a regular USB cable.

Finally, I aligned the X-Y coordinate system in the K40 laser with that from Inkscape (bottom, left instead of top, left) so your work layout in Inkscape matches exactly that of the laser. This was achieved by adding an L shaped bracket (90 degree angle) to the existing end stop and a simple flag to trigger it.

What do you need to do once you receive Gerbil?

(note: the following instructions will be made available in detailed written and video form)

  • Safety first - turn off your K40 !
  • Unplug and remove your existing K40 controller board
  • Plug in your new Gerbil controller board
  • Turn the K40's Y end-stop 90 degrees and position the end stop flag
  • Install the Open source tool-chain (Inkscape, laser plugins, g-code sender) on your PC or MAC

Now you're ready to test - engrave a small picture and calibrate the firmware/tube power range (one parameter in Gerbil).

And you're done and can start being productive!

Project Timeline

Not much to be extended since we have done all the development work, it's just a supply chain from here.

The Project Time Line
The Project Time Line

The team behind the Kickstarter campaign

Paul de Groot, tinkerer and crazy inventor, has a B. Sc in electronics engineering. In daily life he works as a Business Architect to solve the challenges within the Australian Health sector.

Dan Collins, mad scientist and creator of the Personal Particle Accelerator STEM kit is a Data Scientist in daily life solving complex Big data and analytical puzzles.

Risks and challenges

Design risks are low since the product has been designed and successfully tested on multiple machines. Paul has had the Gerbil running on his K40 machine for one year.
Discussions with many other K40 owners indicates that all K40's use the same stepper motors and the same laser tube. Variability between K40’s appears restricted to the connectors, and two types of power supplies. The mitigation strategy is to use beta users from the Google+ K40 forum for various models before ordering and starting the production.
Production has already been tested - The supply chain risks are low because the production partner has already successfully produced good quality PCB’s and assembled units.
The production strategy is to place several batch orders, rather than a single large order. This should allow ongoing quality testing to quickly address any quality problems that arise.
Finally, the test plan is to test 100% of boards before sending to backers.
Ability to scale - our production partners are professional commercial operators, and are able to scale to large production volumes. We've established links and budgeted for a large local facility to perform testing and distribution of rewards, so that backers are not dependent on our personal time to execute these aspects.
Shipping rewards - will occur from Australia, with backers responsible for ensuring the product is suitable for their jurisdiction/locality, and if applicable, the payment of any inbound customs duty.
Timeline - we've planned a day by day schedule that integrates all our suppliers, transport, testing etc, and allowed a bunch of time for last minute delays, so we're confident that we can deliver by the time frames stated in the rewards.

Learn about accountability on Kickstarter
Questions about this project? Check out the FAQ

Funding period

- (30 days)

Line icon alert icon Artboard Copy 8 arrow-down icon arrow-down arrow-left icon arrow-left arrow-point-left icon Fill 1 Copy 5 arrow-point-right icon Fill 1 arrow-right icon arrow-right arrow-up-right icon icon--arrow-up-right copy bar-chart icon Artboard Copy 6 bell icon Combined Shape Copy 5 book icon Artboard Copy 3 bookmark icon Fill 1 brand-assets icon Artboard Copy 13 cart icon Artboard Copy 4 chat icon chat check icon Fill 1 Copy 6 circle-back icon Fill 1 Copy 13 circle-forward icon Fill 1 Copy 16 circle-k icon circle-k circle-left icon circle-left circle-right icon circle-right clipboard icon Artboard Copy 12 clock icon Combined Shape close icon close closed-caption icon Fill 1 compass icon Combined Shape Copy 2 conversion icon conversion delta-down icon Fill 1 delta-left icon delta-right icon Fill 1 delta-up icon Fill 1 duplicate icon duplicate embed icon Combined Shape Copy 6 eye icon Combined Shape Copy 12 facebook-contained icon Facebook Contained facebook icon Facebook logo flag icon Fill 1 Copy 3 gear icon Fill 1 Copy 14 global-africa icon Fill 1 Copy 9 global-america icon Fill 1 Copy 10 global-asia icon Fill 1 Copy 17 graph-bar icon Combined Shape Copy 9 graph-line icon Combined Shape Copy 16 heart icon Fill 1 Copy 8 help icon human icon icon--human icon--activity-feed.kds icon icon--add-heading.kds icon icon--advanced-analytics.kds icon icon--alarm icon icon--alarm icon--alert icon icon--alert icon--alt-text.kds icon icon--arrow-down.kds icon icon--arrow-down icon icon--arrow-down icon--arrow-left-2 icon icon--arrow-left.kds icon icon--arrow-left icon icon--arrow-left icon--arrow-right.kds icon icon--arrow-right icon icon--arrow-right icon--arrow-up-right icon icon--arrow-up-right icon--arrow-up.kds icon icon--arrow-up icon icon--arrow-up icon--backer-badge icon icon--backer-badge icon--bar-graph.kds icon icon--bell.kds icon icon--bell icon icon--bell icon--bold.kds icon icon--bolt.kds icon icon--bolt icon icon--bolt icon--bookmark-filled.kds icon icon--bookmark-outline icon icon--bookmark-outline icon--bookmark.kds icon icon--bookmark icon icon--bookmark icon--bulleted-list.kds icon icon--calculator icon icon--calculator icon--calendar-check icon icon--calendar-check icon--calendar.kds icon icon icon--calendar icon icon--calendar icon--campaign-outline icon icon--campaign-outline icon--caption.kds icon icon--captions.kds icon icon--cart.kds icon icon--category.kds icon icon icon--chat.kds icon icon--check.kds icon icon icon--check icon icon--check icon--chevron-down.kds icon icon icon--chevron-down icon icon--chevron-down icon--chevron-left.kds icon icon icon--chevron-left icon icon--chevron-left icon--chevron-right.kds icon icon icon--chevron-right icon icon--chevron-right icon--chevron-up.kds icon icon icon--chevron-up icon icon--chevron-up icon--circle-around.kds icon icon--circle-around icon icon--circle-around icon--circle-back icon icon--circle-back icon--circle-backward.kds icon icon--circle-check icon icon--circle-empty icon icon--circle-forward.kds icon icon--circle-forward icon icon--circle-forward icon--circle-loader icon Page 1 icon--circle.kds icon icon--circle icon icon--clipboard icon icon--clipboard icon--clock.kds icon icon icon--clock icon icon--clock icon--close.kds icon icon icon--closed-caption icon icon--closed-caption icon--code icon icon--code icon--collapse.kds icon icon--collapse icon icon--collapse icon--commissions icon icon--commissions icon--compass icon icon--compass icon--confirmation icon icon--confirmation icon--conversion.kds icon icon--conversion icon icon-conversion icon--copy.kds icon icon--cpu icon icon--credit-card.kds icon icon--credit-card icon icon--cross icon icon--cross icon--curve-right icon icon--curve-right icon--date-and-time.kds icon icon icon--delta-down icon icon--delta-down icon--delta-left icon icon--delta-left icon--delta-right icon icon--delta-right icon--delta-up icon icon--delta-up icon--download.kds icon icon--download icon icon--download icon--drag.kds icon icon--edit.kds icon icon--ellipsis.kds icon icon--ellipsis icon icon--error.kds icon icon icon--expand.kds icon icon--expand icon icon--expand icon--external.kds icon icon icon--external icon icon--external icon--eye icon icon--eye icon--facebook icon icon--facebook icon--filter icon icon--filter icon--filters.kds icon icon--flag-outline icon icon--flag.kds icon icon icon--flag icon icon--flag icon--forward-fund icon icon--frown-filled icon icon--frown icon icon--fulfillment.kds icon icon--gear icon icon--gear icon--globe-africa icon icon--globe-africa icon--globe-america icon icon--globe-america icon--globe-asia icon icon--globe-asia icon--globe.kds icon icon--graph-bar icon icon--graph-bar icon--graph-line icon icon--graph-line icon--hamburger.kds icon icon--hamburger icon icon--happy-filled icon icon--happy icon icon--header-anchor icon icon--heading.kds icon icon--heading icon icon--heart-filled.kds icon icon icon--heart-outline icon icon--heart outline icon--heart-thin-outline icon Fill 1 icon--heart.kds icon icon icon--heart icon icon--heart icon--heartstrings-and-hardbacks icon icon--hide.kds icon icon--home-with-door icon icon--home.kds icon icon--home icon icon--home icon--human.kds icon icon icon--human icon icon--human icon--humans.kds icon icon--humans icon icon--humans icon--image.kds icon icon--image icon icon--image icon--inbox.kds icon icon--inbox icon icon--inbox icon--indeterminate icon icon--info.kds icon icon icon--info icon icon--info icon--instagram icon icon/instagram icon--intermediate.kds icon icon icon--italic.kds icon icon--late-pledges.kds icon icon icon--lightbulb.kds icon icon--lightbulb icon icon--lightbulb icon--line-graph.kds icon icon--link.kds icon icon--link icon icon--link icon--location.kds icon icon icon--lock-black-bg icon lock-icon icon--lock icon icon--lock icon--locked.kds icon icon icon--log-out.kds icon icon--long-story-short icon icon--mail icon icon--mail icon--make-100 icon icon--media-embed.kds icon icon--meh-filled icon icon--meh icon icon--menu icon icon--menu icon--message.kds icon icon--message icon icon--message icon--milestone-dfm icon icon--milestone-idea icon icon--milestone-preprod icon icon--milestone-prod icon icon--milestone-proof-of-concept icon icon--milestone-working-prototype icon icon--minus.kds icon icon--mobile.kds icon icon--mobile icon icon--mobile icon--mute.kds icon icon--numbered-list.kds icon icon--order-management.kds icon icon--overflow icon icon--overflow icon--pause.kds icon icon--pause icon icon--pause icon--pencil icon icon--pencil icon--pie-chart icon icon--pin.kds icon icon--pin icon icon--pin icon--pinterest icon icon--pinterest icon--play-filled.kds icon icon--play.kds icon icon--play icon icon--play icon--pledges.kds icon icon--plus-human.kds icon icon--plus-human icon icon--plus-human icon--plus.kds icon icon--plus icon icon--plus icon--prohibit icon icon--prohibit icon--prohibited.kds icon icon--project-budget icon icon--project-we-love icon icon--pull-quote icon icon--pull-quote icon--pullquote.kds icon icon--question-filled icon icon--question-filled icon--question.kds icon icon--question icon icon--question icon--reorder icon icon-reorder icon--reply.kds icon icon--reply icon icon--reply icon--reward.kds icon icon icon--reward icon icon--save icon icon--save icon--saved icon icon--saved icon--search.kds icon icon--search icon icon--search icon--section-break icon icon--section-break icon--sentiment-neutral-filled.kds icon icon--sentiment-neutral.kds icon icon--sentiment-satisfied-filled.kds icon icon--sentiment-satisfied.kds icon icon--sentiment-unsatisfied-filled.kds icon icon--sentiment-unsatisfied.kds icon icon--settings.kds icon icon--shipping.kds icon icon--show.kds icon icon--small-k icon icon--sound-hi icon icon--sound-hi icon--sound-lo icon icon--sound-lo icon--sound-mute icon icon--sound-mute icon--spinner.kds icon icon--star-outline icon Star Outline icon--star.kds icon icon icon--star icon icon--star icon--stopwatch.kds icon icon--subtitles-captions icon icon--subtitles-captions icon--success.kds icon icon icon--survey-multiple-choice.kds icon icon--survey-open-text.kds icon icon--survey-single-choice.kds icon icon--survey.kds icon icon--tax-documents.kds icon icon--text-bold icon icon--text-bold icon--text-bullet icon icon--text-bullet icon--text-italic icon icon--text-italic icon--textalign-centered icon icon--textalign-centered icon--textalign-right icon icon--textalign-right icon--thumbs-down icon icon--thumbs-down icon--thumbs-up icon icon--thumbs-up icon--thumbsdown-outline icon icon--thumbsdown-outline icon--thumbsup-outline icon icon--thumbsup-outline icon--timeline-to-do.kds icon icon--trash.kds icon icon--trash icon icon--trash icon--tumblr icon icon--tumblr icon--twitter icon icon--twitter icon--unlink.kds icon icon--unlink icon Artboard icon--unlock icon icon--unlock icon--unlocked.kds icon icon icon--update-freeform-round icon icon--update-freeform-round icon--update-freeform icon icon--update-freeform icon--update-pinned icon Artboard icon--update-qa-round icon icon--update-qa-round icon--update-qa icon icon--update-qa icon--upload.kds icon icon--upload icon icon--upload icon--video.kds icon icon--video icon icon--video icon--volume-down.kds icon icon--volume-up.kds icon icon--warning.kds icon icon icon--warning icon icon--witchstarter icon icon--youtube icon icon--youtube icon--zine-quest icon icon-imagealign-center icon icon-imagealign-center icon-imagealign-left icon icon-imagealign-left icon-imagealign-right icon icon-imagealign-right info icon Combined Shape Copy instagram icon instagram copy kickstarter icon Artboard Copy 5 leaf icon leaf lightbulb icon icon--lightbulb link icon Combined Shape Copy 8 loading-spin icon lock icon Combined Shape Copy 4 mail icon Combined Shape map-pin icon Fill 1 menu icon Group message icon Fill 1 Copy 12 mobile icon Page 1 Copy 2 pause icon pause copy pencil icon Combined Shape Copy 3 pin icon Combined Shape Copy 11 pinterest icon pinterest play icon play copy plus-human icon icon--plus-human plus icon Fill 1 Copy 7 question icon Combined Shape Copy 14 search icon Fill 1 Copy 11 shapeshift icon share icon Fill 1 Copy slash icon solid-arrow icon solid-arrow sound-hi icon Combined Shape sound-lo icon Combined Shape sound-mute icon Combined Shape star icon Fill 1 Copy 2 stopwatch icon Group 2 thumbs-up icon Shape tools icon Shape trash icon Combined Shape tumblr icon tumblr copy twitter icon twitter copy user icon Artboard Copy 10 volume-up icon Artboard Copy 9 warning icon Combined Shape Copy 10 write icon Artboard Copy 11 x icon Fill 1 Copy 4 youtube icon Combined Shape