Summary

A similar test object to one provided by ttsalo to measure warpage of a specific material, in this case, 618 Nylon.

Instructions

As Nylon is the base material of 618 Co-Polmer it is extremely slippery and being slippery is one of 618's benificail properties. However, this slippery property makes bonding of the first print layer to the print bed difficult with standard methods used by printers of ABS.
The Nylon base will stick extremely well to any cellulous material. Garolite LE is a low cost board material (Sometimes called a "Composite") that is manufactured by soaking a combination of cloth and cellulous fibers in a heat curable resin, then compressing the laminations as heat is added. The result is an extremely stong board like material with a smooth surface. With an increasing number of Industrial users along with Universities and machine shops wanting to print 618 with accurate dimentional and surface flatness qualities, a series of tests were divised using the attached .stl.
As the amount of material printed increases, the applied thermal stress increases on layers below. While other materials did well with prints that had limited first layer surface area, only the Garolite LE performed to the requirments of these organizations. In testing, the Garolite performed to the point of needing to have some of the surface area taped off to "limit" contact with 618 as early parts had to be removed destructivly.
As noted in the attached photo, over 50% of the contact area is taped off from the Garolite to accomodate part removal.

The part is 150mm long, 90 degree wedge, 10mm wide at the top and 2mm wide at the contact surface.
The photo shows a part printed:
88mm/s
245C
.4mm nozzle
35% fill
2 perimeters
1 solid layer

After one hour of cooling, there was less than one thread separation at the the extreme ends and then only one end.
The test part was allowed to normalize for 2 hours and then bowing along the long axis was measured at less than .2mm

Garolite LE Source = McMaster Carr
http://www.mcmaster.com/#catalog/119/3609/=l4hmv3
12" x 12" =
8474K121
8474K131
8474K141
8474K151
6" x 6" =
6842K61
6842K62
6842K63

Reference was http://www.thingiverse.com/thing:26955

High Strength Print Bed for 618 Nylon