Clearance holes in bumper backing

[FRC58]

The Kitbot frame has bolt heads on the outside of the frame rail. To have the bumper plywood fit flush against the outside rail the 3/4" plywood backing would need to have small recesses to accommodate the bolt heads. Is it permissable this year to have the small recesses in the bumper backing?

[FRC1346]

I believe it is implied in the rules that the only holes (through, partially through or otherwise) in the 3/4" plywood bumper backing material are those specifically used for bumper mounting, but I have not been able to see where it is specifically stated.

In past years some teams have assumed that they may make shallow, blind holes, carvings or other excavations in to the bumper backing so that they may more easily mount their bumpers around inconvenient protrusions from the robot, such as the head of an axle bolt, so long as such holes have insignificant impact on bumper integrity.

I believe it would help teams and tech inspectors to have specific clarification of the following points:

A) Other than holes used specifically for mounting the bumper, is a hole, of any diameter or depth, in the 3/4" plywood bumper backing material permissible?

B) In the event a team has mistakenly drilled a non-compliant hole in the 3/4" plywood bumper backing material (for example they may have drilled a hole for a mount point, then moved the mounting point leaving that hole unused), is it acceptable for the team to re-fill the hole in a suitable fashion (expoxy and saw dust, or a glued dowel or plug are a couple possibilties) to satisfy the bumper construction requirements.

Thank you,

Jason

[GDC]

Holes in the plywood backing of the BUMPERS for the purposes of accommodating protrusions on the ROBOT are not prohibited by the rules. Likewise, there is no prohibition against moving a hole.