Overview

I got a notice from Shapeways that … “This is a friendly reminder that your model “Mooring Cleat – 3.5 mm – 320ea” from order “3617780” was taken out of production by one of our 3D printing engineers due to design issues.

Honestly .. I was like .. “Whaaaa….” .. and had to look it up. I had uploaded the darn thing way back April 27, 2018 .. I had slept since then! I had to pull up the old files to refresh my memory.

I had found the drawing to the left online for a company selling the cleats. With such a fantastic drawing to work with I fairly quickly used it to create a CAD file in Sketchup.

With the Pull Tonnage and dimensions shown in the chart someone could simply take the “C” measurement to scale and cross-index to find what size it would be in whatever scale one was working with.

3.5 mm Cleat

The model which measures 3.5 mm across the ends of the horn. The measurement “C” is shown .. the base width .. as 1.2 mm.

Modifications for printing include increasing the base thickness and adding bolt heads.

If you compare that 1.2 mm base width you can see ….

The closest one would be N scale at 192 mm. If you scale it we get \frac{220}{5} \approx \frac{192}{X}=220X \approx 960=X \approx 4.36 \text{ tons}

design issues

So this is the problem as identified by Shapeways’ “3D printing engineer”

Yepper. The minimum “wall” at Shapeways .. and on my own prints is .3 mm .. and I prefer .4 mm if possible if any pressure will be on the objects. In this case, being purely decorative the .3 mm would be fine. Except .. it isn’t .. .3 mm

I pulled up the model in Sketchup and .. sure enough .. the end of the horn which I am showing here in red is less than that .3 mm dimension. Oops! My bad@The solution? Redesign the cleat so the horn is no smaller than .3 mm .. or maybe .. .4 mm.

This is what you run into when designing in 3D. Sometimes .. you think you are “good to go” .. and instead you crash in flames. The answer is to drop back and punt.

UIpdate

Version 1 is in gold at the back. Up front in blue is Version 2. I cut off the horns where the horn was at .4 mm .. then tapered out to .3 mm on the end of the horn.

I did chamfer the end of the horn. Hopefully that will not kick the model back again.