# OpenBeam Kossel Pro



## compsurge (Feb 20, 2015)

I backed this printer on Kickstarter somewhere around a year and eight months ago and finally received my printer in the end of December. Honestly, I was disappointed in the delays, but I knew going into the Kickstarter there was a risk of schedule slip. Month after month, I followed the OpenBeam site religiously and was kept up to date - as excruciating as it sometimes felt.

All of my angst was put to bed as soon as I opened the box. To state it simply: I was amazed at the attention to detail and level of quality for every component of this printer. The price I paid is a steal for the product I received.

Aside from the OpenBeam extrusions (available on Amazon), most of the parts on this printer are injection molded with EMS Grivory. The fit and finish is excellent. The linear rails wear in and I have noticed they are much smoother now than out of the box.

My prints have turned out for the most part, excellent. I am using PLA almost exclusively. I hate the warping characteristics of ABS and I have never been happy with an ABS part I've made on any "open-air" printer.

Throughout my use, I have only one complaint: the heated bed probe. I have not found automatic deployment reliable at hitting the limit switch every time and have resorted to manual deployment. The printer will automatically retract the probe at the end of the G29 bed leveling sequence by using one of the heated bed glass mounts.

Currently in development are modifications to existing stainless steel hot ends for use of higher temperature materials such as polycarbonate and nylons.

Here are some pictures of the build.

Here is a video where I go through some of the aspects of the printer:







If you are interested in the printer, it is available here for preorder: www.matterhackers.com/store/printer-kits/openbeam-kossel-pro


Note on Filaments:

I recommend Hatchbox PLA filament. I stocked up on it while it was $23/1 kg spool on Amazon. It prints very well and is consistent at 35-40+mm/s at the correct settings (I still have more to tweak!).

I successfully printed with Proto Pasta Carbon Fiber PLA, which is recommended for direct drive 0.5mm nozzles. The OpenBeam Kossel Pro is a 0.35mm nozzle with a Bowden extruder.

I DO NOT recommend MG Chemicals translucent PLA. It prints great, but - and this is a huge but - the filament breaks a lot. I currently have a jammed Bowden tube because of it and will need to get a replacement from McMaster if I can't use some metal wire to push it out...


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## john_c_kennedy (Mar 18, 2015)

Tim, great video and super cool printer.  I'd like to see some pix of some things you've printed.

John


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## compsurge (Mar 18, 2015)

Thanks for the kind words.

Most of my photos are here: https://instagram.com/protoserge/

Unfortunately, I made a lot of the same part over the past few months, but never took a photo of it (1.25" diameter gear with boss). The last attempt I made failed (a full Seej catapult). I have to add glue stick to the bed for next time.


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## compsurge (Sep 3, 2015)

I have found that Elmer's glue diluted in about 1:5-1:8 parts water is an excellent bonding surface for PLA and nylon filament. If you have warping issues on your printer, try this out.

I have had several prints for testing the CAD models for my CNC conversion. It has been great knowing I can recycle the plastic versus scrapping the metal when things don't work right. I'm almost ready to start making a thread on my conversion - I just need time to grab the camera and document the steps.


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