Nozzle suction

[0xBERNDOG]

My pump has good suction, but it's all lost when going through the nozzle

Did you do anything in particular to seal it? I'm trying to diagnose where the losses are coming from

[0xBERNDOG]

The most likely causes I can see:

• loose fit of the bearing at the top of the nozzle
• loose fit of the PTFE tube inside the bearing

[xpDIY]

When you say lost suction, what do you mean? Do you have nozzle tip installed? There is no suction from the nozzle at all or only small amount of air coming from noze tip? I didn't do anything special, when you fit the bearing on the top, is it tight? Also I have found sometimes the nozzle tip print out could have air leakage if not pirnted well, I normally connect the air output port of the pump and put the nozzle into water and check where is leaking. Or simply blowing into the nozzle while blocking the other end by hand to check if nozzle itself is leaking. Sent from Outlook for Android<https://aka.ms/AAb9ysg>

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[0xBERNDOG]

I identified the problem areas, and fixed it by modifying the mesh in fusion360:

1. The bearing was loose, so I made the hole 12.10mm diameter
2. My O-rings were actually 1.5mm tall, so they weren't sealing against the nozzle. I modified the end to pull the nozzle further down so that it properly squashes the O-ring

Now I can pick up my OpenPnP test pieces (hole punches) :)

[xpDIY]

ok, glad it worked for you! I think it make sense to make parts with different tolerance..

[0xBERNDOG]

A parametric model would work well, so the user can adjust the tolerance parameters

[bonz099]

The new nozzle was a bit thin for me, and my printer sucks, so I dipped the whole lower part in conformal coating and let it drip dry. It has way better suction now.

[xpDIY]

@bonz099 Thanks for the feedback, the tolearance is a challenge for different 3D printer, a parametric model will help in this case, I will see if I can provide something for that.