I made one based on the design of iddee's bee vac
I made it so that the plexiglass can slide to regulate vacuum, and instead of #8 hardware cloth used window screening I had on hand already.
Window screen restricts airflow too much, I intend to replace it with #8 hardware cloth. The airflow I had was barely acceptable, but was very gentle on the bees. I don't think that there were many losses attributable to the vac.
I used a smooth hose.
All in all, I liked how it worked very much. Another advantage of a sliding plexiglass is that you can pull it partway out and have a lot of ventilation for the bees during transport. If you do that, I'd duct tape the plexi in place once it is adjusted to prevent inadvertent release of the bees if it slipped, though.
I'll try to take and upload some pics in the next day or two, if you'd like.