I know there is nothing new under the sun but I have not seen this so thought I would share it. I was trying to think of a way to hold comb and after seeing what is in use now I came up with this idea.
Plumbers strapping
Cut the strapping to length (I use 8 holes making sure the small hole is on one end)
Bend 2 holes down and use a small metal stud screw to hold it on
Make another bend at the bottom to attach the comb
Use 2 on one side facing one way
Use 1 in the middle if needed facing the other way for more support
The strapping is thin enough that it does not leave a large gap between the bars and I space one bar with strap one without and so forth.
When the bees have attached the comb to the bar take the screw out slide it out of the comb and you are good to go.

I just used this for the cutout posted in swarms and it seemed to work good.