Help with Knievel CP Box size...

[mcseforsale]

OK....I've looked and looked and I've found that Knievel uses a 33"x12" box for his CP.  I built one using a Knievel template but, 12" won't cut it.    The trackball mount is there.

And, if I go up to 13"...which is as small as I can go and capture the trackball inside the CP box, I can't get it wide enough to fit the buttons.


So...do I need to create a curved box?  Or is there a special formula for this?  Is it because I'm using a Happ trackball?

See?  Nutz for trackball are after 12"



But, if I go to 33", I get "underbite" from the CP top...:



THanks!
AJ

[TopJimmyCooks]

since the tops already done, make your front at 12 1/2" or whatever clears the housing of the trackball.  then mark the nuts on the edge of your board and clearance them - cut out wood to recess them into the board.  In effect, bury the nuts in the front of the box. 

or replace the nuts with T nuts. 

[mcseforsale]

Wow.  You sure have a thing for nuts.  Small nuts...t-nuts...Geez.   

(c'mon...after typing all that you had to know that was coming!   )

Anyway...yeah, I mocked up the CP on what will become the box base and at 12 1/2, it would still screw me because the right joy will then have to be clearanced.   

So, I'm just going to build the box with a pointy nose.     So, 12" at the sides and 13 1/2" in the middle...compensating for the 3/4" dimension of the wood.  It's how I built this:



But, smaller of course!  That friggin thing was 19" x 48"   

The sides of it were 1x4, but I think I'll build this out of 3/4 MDF @ 5"....the slope is built into the cabinet sides, so I can build the box square.

AJ

since the tops already done, make your front at 12 1/2" or whatever clears the housing of the trackball.  then mark the nuts on the edge of your board and clearance them - cut out wood to recess them into the board.  In effect, bury the nuts in the front of the box. 

or replace the nuts with T nuts. 

[mcseforsale]

OK.  I finally got this done.  I was dreading it...although I don't know why.  I had the wood cut in about an hour in the driveway.   

So, the "bump box" is 13 3/4" at the front and just over 11 1/2" at the sides OVERALL.  Not sure what the angle of the bump is, but the front of the bump is 10" edge to edge and the angles are very shallow.

The overhang all around is about 1"




A pair of dowel rods are glued into the cabinet sides and stick out about 1/2" to locate the CP box accurately.  I'll file them down with a rounded profile once the gorilla glue dries.  These are not glued to the CP box...the box will be anchored to the cabinet with these dowel pins and a latch for easy takeapartability.




Here's the profile of the box.  I still need to flush a couple of the edges.  My math-fu sucks, so I tend to let edges fly and only concentrate on the angles.  I'm going to cut the wild edges, then round the corners to a nice profile that matches the Kneivel CP top.



Here it is with my CP on top.  The box will allow the Happ TB mount to have about an inch of room in there. 



Thanks for the reply.  I guess once I thought about it the answer was right in front of me.

AJ