I wanted a bit longer frame for the otherwise great Peon230 quad frame by Tech2C.
As quick hack, I simply cut the STL mesh files (Peon230_Base_v1.1.stl and Peon230_Top_v1.1.stl) into 2 parts (with Meshimixer Linux) to overcome Tinkercad STL upload triangle limit. In Tinkercad I mirrored the 2 longer frame parts (back part of Peon230 frame) and joined them together in the middle. Then I used part of the front of Peon230 to make the front the same as original.

The resulting frame gives you ~248mmm diagonal, thus Peon248 :) Motor shaft distance front-to-back becomes ~158mm and side-to-side reamins the original 190mm of course.
Came out nice printed in orange PLA 30% infill, 3 shells, 3 top and bottom layers.