The bowden fan is an interesting idea.
https://ultimaker.com/en/community/3435-new-fan-cooling-design#reply-19327
https://ultimaker.com/en/community/3435-new-fan-cooling-design#reply-19299
Hi replacing the fans with an airjet has worked out well for me as it givesme more control of temp when printing.Fans can produce to mutch air to the wrong place that can have an adverse efect on buildplate temp and nozzle temp
resulting in bad prints and other problems plus they add extra weight to the moving printhead. I printed a Tourbillon watch by Christoph Laimer with the airjet with very few problems.
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