NebuCHADnezzar Comments - Answer Overflow

NebuCHADnezzar

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RRCRat Rig Community [Unofficial]

•Created by tg73 on 10/8/2024 in #fix-my-print

Regular surface distortion pattern towards end of larger first layers VC4

would love to know how the geometry and youngs modulus effect the way it expands and deflects

2112 replies

RRCRat Rig Community [Unofficial]

•Created by tg73 on 10/8/2024 in #fix-my-print

Regular surface distortion pattern towards end of larger first layers VC4

would love to see the calculations... ye that a small change in length will result in a larger deflection was also my guess from my primitive look at the change in length... but I wasnt able to imagine how exactly it results in that... would be nice to see a simulation of this so you could see what excactly is happening

2112 replies

RRCRat Rig Community [Unofficial]

•Created by tg73 on 10/8/2024 in #fix-my-print

Regular surface distortion pattern towards end of larger first layers VC4

isnt it also super hard to machine?

2112 replies

RRCRat Rig Community [Unofficial]

•Created by tg73 on 10/8/2024 in #fix-my-print

Regular surface distortion pattern towards end of larger first layers VC4

how does it work? can you show how a complete calculation of the issue would look like?

2112 replies

RRCRat Rig Community [Unofficial]

•Created by tg73 on 10/8/2024 in #fix-my-print

Regular surface distortion pattern towards end of larger first layers VC4

it wasnt really meant to be a precise calculation, just to understand the tendency and where the deflection is coming from... and we noticed, what I described... think we were calculating it for a 730mm lenght (I didnt know the excact lenght of the extrusion and just guessed it at the time) and we took the following values and formula for the lenght difference: pure aluminium coefficient: 0.0000238 1/°C alloyed Steel: 0.000161 1/°C pure titanium: 0.000009 1/°C formula: delta l = coefficient * lenght * delta temperature I think we were calculating it for delta t of 45°C or 55°, not sure anymore... but you dont even have to really calculate you can already see that the ratios are not too different between the coefficients (atleast for the pure materials)... maybe the specific alloys are off by more than I thought, I thought it wouldnt matter too much for this sort of quick "rough calculation" for understanding where this issue is coming from and how much lenght difference we are talking off roughly... just to get a feel for the order of magnitude...

2112 replies

RRCRat Rig Community [Unofficial]

•Created by tg73 on 10/8/2024 in #fix-my-print

Regular surface distortion pattern towards end of larger first layers VC4

I have a question to the experts of this bowing topic... I was talking to a buddy from work about this issue and we ended up calculating the lenght difference for 55°C temp difference with the cte for pure titanium (might be off since toro is some alloy?) and the cte for a common alloy steel (might also be off slightly from the actual cte of the alloy used in the rail) and then compared it to results with aluminium extrusion... The values were pretty small compared to what we are seeing in the bedscans (0.15mm)... And also the cte of titanium and steal have the roughly the same ratio as steal/aluminium (steal roughly double of titanium and aluminium double of steal) so the forces resulting on the rail should be reversed, but the lenght difference is almost the same... So we were asking ourselves how this results in this large bowing effect we are seeing and why titanium actually fixes it if the cte is rougly off by the same factor just reversed... Hope this is not a dumb question... Just trying to better understand whats exactly happening in detail...

2112 replies

RRCRat Rig Community [Unofficial]