The MakerSlide profile is going to change slightly in the future. The old profile was proving difficult to extrude. There were material flow issues centered around unslotted portion of the face of the profile. While the critical v groove features were not affected, the old profile had some issues.
The unslotted section tended to droop a little and not be perfectly straight. It also was inconsistent in thickness. It gave the appearance that the extrusion was warped in that plane.
1. Some of the angular webs were not the full thickness they should be in that area.
2. As a result the material was being extruded in an easier to extrude alloy of
6063-T6.
The new profile removes one web which will significantly improve the support of the extrusion tool insert that creates the void and improves the material flow in that area. The new profile will be extruded in a more structural alloy of
6105-T5.
I believe this will result in a small net gain in rigidity. The critical parameters are Area Moment of Inertia and tensile strength and Modulus of Elasticity. The cross section values are calculated. In reality, less than the full cross sectional area was present in the current profile.
These are the before and after values of those numbers.
Before
Area Moment of Inertia: (mm4): (X) 1.61 x 104 (Y) 6.10 x 104
Ultimate Tensile Strength: 38 ksi
Modulus of Elasticity: 69 GPa
After
Area Moment of Inertia: (mm4): (X) 1.58 x 104 (Y) 6.07 x 104
Ultimate Tensile Strength: 30 ksi
Modulus of Elasticity: 70 GPa
It will also give a little more room for wiring.