The first laser cutting for Grisbot went smoothly and the blue acrylic is beautiful. Now let’s do a checkfit as the Sketchup design encounters the physical world.

Here are the pieces snapped together:

No problem here. The pieces come together just like a puzzle!

Now let’s tighten the bolts:

You’ll have to take my word for now, but it’s all very snug and there’s no jiggling of the frame once the nuts are finger-tight.

As you can see in the following two photos, battery and breadboard have more than enough room:

(Bolts were inverted for these checks, of course.)

Now a look at the ball caster:

Here we have a problem. My Sketchup model of the caster didn’t have the diamond-shaped base and I’m paying for it. The bottom piece of the robot casing will have to be extended back (ie, to the right in the photo) at least an eighth of an inch so that the bolt holes will align, and maybe add another eighth inch so that the ledge fully covers the base.

Now it’s time to check the servo fit, which is likely to have problems because the servo model I downloaded from Sketchup Warehouse turned out to not have the right dimensions and so I had to make my own servo model based on personal eyeball measurements.

Alas, to obtain the servos, I have to ‘cannibalize’ my beloved Grisbot Prototype #1, so here is a loving last picture:

And now we checkfit the servo, and . . .

SNAP! Not good. The fit was so tight that one of the acrylic sides broke as I tried to force the servo into position. Maybe a sixteenth of an inch horizontal and vertical widening will reconcile the fit, and I think I’ll have to give a closer look to the bolt hole alignment too.

So, in summary, there are three checkfit fails: the caster and the two servos. To accomodate, I’ll redesign the bottom and side pieces and then it’s back to the laser cutter tomorrow. Results will come on Thursday.