Hi Matadem

I do not have SheetCam or know much about it, but did a little google searching:
DXF from other software seems to also have scaling issues:

See:
https://forum.langmuirsystems.com/t/sheetcam-scaling-issues/8907/3
ttoy360
CrossFire PRO
May '20
it may be the way you are saving the file from fusion do not export to a .dfx file. Instead right click on the box it will be on the left side of the sketch under “Origin” “Sketch” this will bring up a menu and you will see save as a dfx. Click on that and save the file as a .dfx and the open that file in sheetcam. If you export the file it will be off in dimension…

(MoI has a Save AS dxf, and also an Export to dxf. (I do not know what the difference may be, if any.)

- Brian

Old MoI posts, 2007:
http://moi3d.com/forum/lmessages.php?webtag=MOI&msg=918.41