Reflow Troubles, CubeCell Module Plus

Hello,
I made this new board. It uses the cubecell module plus.
I’ve found it extremely difficult to reflow properly. Granted I am using KiCAD and thus made my own footprint, but it is a 1 to 1 direct copy from the Altium Footprint supplied by Heltec. The boards looks like this.

I found it extraordinarily difficult to reflow properly. I think this stems from three problems.

  • It’s big, you can’t place it precisely with a regular tweezer. You sort of have to do ur best guess, then push the corners till it sorta aligns. Of course, when it’s on the solder paste, it doesn’t really want to move.
  • The pads are really close together. I got like 6 or 7 shorts after the reflow process. It may be due to the fact that half of the pads goes underneath the module, and the extra solder paste shorts it.
  • It’s heavy. So heavy that it can’t adjust its position during the reflow process like other components do.
    Has anyone else met these problems? Any tips? As far as I can tell, this module would cause too many manufacturing issues for production at scales of thousands.

hi,

We just communicated with our pcb factory and they gave some opinions.

  1. Do not design the length of the pad to be too long to prevent connecting tin.

  2. Set the temperature higher than ordinary reflow soldering. about 220 Celsius.

Awesome thanks.

I am thinking of decreasing the pad lengthwise. Just have it long enough to touch the stamp hole.
I am also thinking of decreasing it widthwise just to increase the gap between pads and increase thermal insulation.

What do you think about these two idea?

hi,
We have customized similar products for customers before, you can refer to the picture below.


Looks great!
Is it possible to get the footprint of that?

Could we have footpad in Lucas file please to help community use cubecell module. Thanks Simon.

hi,

here is a link:
https://resource.heltec.cn/download/CubeCell/HTCC-AM02_Module