With the ever present goal of keeping the mass of the end effector as low as possible, the previous cooling solution for the M2 was getting out of hand.
It involved a large radial blower mounted to the rear of the floating stepper carriage, a flexible duct, and an engineered, 3D printed nozzle with two distinct flow characteristics. Low speed flow would result in a precise cone of air surrounding the nozzle, and high speed flow would result in an additional air-multiplication effect from surface flow.
It worked, but it was completely excessive and still added 10 grams to the print head mass. Cooling was a wash of air near the print bed, cooling it, the part, and the print head itself far too much. It also did not solve the issue of part cooling in an enclosed build area.
So we went looking for a better solution and found Berdair.
Sadly they were not in stock, so we mocked up our own version with a bit of AL tubing, and drove it from a compressed air source. Stainless would be superior here, but the AL was easy to form and most importantly, in the shop.
The results were fantastic. It produced exactly the effect we were after with the first design: A precise cone of air intersecting just below the nozzle, but without the excessive wash.
Then came time to pack up and head to MRRF, and leave our compressed air source behind.
We installed a surplus micro 12v air pump we had acquired during a recent expedition to Skycraft.
It was woefully inadequate.
We looked around for Berdair at the show, but didn't look hard enough. They were there, but had sold out of the pumps the first day and so the marker we were searching for did not exist.
So for the entire show, we printed with basically zero part cooling. This really limited the top speed we could get on the single wall print I loved so much to a paltry 45mm/sec.
Yesterday in the mail our Berdair kit finally arrived.
Comparison of the pump we were using, to the new Berdair pump.
I can't wait to try it.