Getting 1/64" difference in- and outside Block

Ok, so here’s something that’s wasted a ton of my time until I just figured out this happens. I have my Units set to 128th of an inch. Select the block and you see 7’-4 1/64" in the Box Edit window.

Click inside the Block, and BoxEdit says the geometry is 7’-4"

Can someone please take a look at my settings and tell me what’s going on? It’s driving me nutso that my geometry isn’t lining up, and it effects the looks of my Sections, etc.


1-64in off Block.3dm (152.9 KB)

Hi Alan - the more precise difference in Bounding Box height is

inside BlockEdit
Length = 87.9983215 inches

Block instance:
Length = 88.0120888 inches

= 0.0137673 difference … I’ll investigate.

Hm, I guess the answer is, now that I look at it in model units (feet) and not inches, the discrepancy is just about file tolerance - .001. On the other hand it does not improve with tighter tolerance. Still poking…


Thanks, very much appreciated. Feeling like I’m not able to be confident in my modeling because of this

Hi Alan - keep in mind that the 64th in inches and your file is using feet as the unit, so the discrepancy is no4 1/64th of the current file unit, it is closer to 1/1000.

@Alan_Farkas - it turns out there’s a curve on an off layer in that block that is causing the discrepancy.


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