One of what I’d consider “step up” machines for metal milling from Shapeoko is the langmuir MR-1. Obviously completely different target markets, company, price points, and use cases.
The way that they are deriving the vast majority of the rigidity/vibration dampening of their machine is with concrete. Initial reviews seem positive and I’d consider it over an hdm if a 4x4 5 pro didn’t fit my target work envelope so much better (and the company wasn’t just entering the market).
You’d never want the increased inertia of a heavier x gantry. However, I wanted to toss my crazy idea of filling the y rails with concrete or epoxy granite out to the community and see just how crazy I am.
I suspect that the limiting factor of any Shapeoko is the spindle and it’d be a waste of energy to do what I’ve proposed.
We have done this in the past (general testing) but the S5 Pro uses precision machined extrusion for the Y and the HDM uses a fully machined billet Y rail.
The bit I can’t work out is what you are making? As I see it the only benefit of a MR1 would be a low RPM spindle and flood coolant - neither of those make much sense on a a 4x4 S5 Pro?
A 4x4 S5 is a big machine, you can throw aluminium, composite, wood etc on it and machine like crazy, there would be no need to add extra mass to the Y rails. If you were machining sheet steel, I’d be thinking a plasma cutter would be more useful?
Looking at the videos and pictures, the Y extrusions are straightened out “Z” shapes (for lack of a better term) and don’t have a cavity to fill. The X gantry might be fillable with some sealing measures with a lighter weight epoxy meant for the job. But those types of vibration reducing measures would primarily be surface finish and more extreme accuracy. In the SO4 Pro at work we already regularly hold 0.005" tolerances and use toolpath strategy with finish passes to achieve those goals. The SO5 should do better with the rails and Z axis already having more mass than previous Shapeoko machines except the HDM.
If your goal is surface finish and accuracy, the first place to start is programming. Learn things like chip load, MRR, roughing strategy, finishing strategy, and use specific roughing tools followed by dedicated finishing tools. That will garner better results.
My query is more of a general “huh I wonder” than a “machine can’t do x. I wonder how I could make it do that.”
When carbide is designing a machine be it a touch probe, nomad, or a Shapeoko design considerations have come into play. One has to be “How am I going to get this to my customer without it costing me 30% of the total value of the machine.” I simply found it interesting how this company chose to solve the mass problem and was wondering its applicability to a machine that can work in a larger work area.
I am interested in the results of the teams testing.
