spiral plane development

[MG1]

Good morning, everyone. I hope to write this post in the right place.

I have this problem. I have to develop on the floor, therefore obtain the development to be able to cut on sheet, a spiral.
If you look at the attachment you will understand immediately. the spiral has ø16 inside and ø49,5 external, thickness 2,8 mm and 1 complete revolution with 28 mm pitch.

I have available only inventor 2017 but I have failed to achieve development in any way. Can anyone help me?

Thank you very much

 

[Cast16]

Try to take a look qui

 

[MG1]

Thank you very much. I've already sent everything to production. Now let's see if the results are the ones hoped.