Burunduk, 100% agree. And the thought was just that, if TP orientation can apply to a pattern then it can easily apply to a single feature, thus being equivalent to Perpendicularity. And I bought into that with equal convincing.
FYI, I was also told to use Concentricity to control coaxiality. I...
3DDave, let me probe this a bit further to clarify something that I may have been mislead on in the past.
I've seen a lot of TP being used to just define orientation, not location. For example, a TP on a hole referenced to datum [A] which is a flat surface. Nothing special here, just a single...
Thanks 3DDave and sendithard, I think you both have collectively reminded me of something.
To be fair, I put the .000 tol as a default. The actual drawing had something like .010 tol. But yes without the FCFs in the figure I provided the envelope / median line principle accomplishes the same...
See attached.
I understand that with the left FCF that Rule 1 no longer applies. The right FCF, though a different symbol, controls the same thing (form of axis). Would Rule 1 also not apply with the TP? This came up on a drawing I reviewed. I told the designer to switch the TP to Straightness...
Our lab previously purchased several BLDC motors with 21 pole pairs and 36 stators. These motors did not come with hall sensors, and previous lab members produced a pcb containing such sensors. They based the spacing on the hall sensors on the number of stators, so the sensors are 40° apart (80°...
Great, thank you both! This lead to some informative searches on my end regarding inhibitors and shear stability. We're going to order a few variants and see what works best across components. My advisor sends his gratitude.
I work in a lab where several gears, shafts, etc. are 1045 CS. I was tasked by my advisor to look into methods that help prevent corrosion. These components are used in walking robots in normal room settings, so no moisture minus lubrication on the gear teeth and oils from skin contact...
So pick a start and end point, one on a hole surface and the other on the OD of the part that sets the min gap calculation. You can think of the start point being fixed, and then you work through the stack up in a way that pushes the end point toward the start point. Pro tip, rotate the part 45°...
I agree with everyone above. TYP is not a standard notation, so it is ambiguous. I've worked with enough people that do this, and when they explain it the same way as the vendor. Since they explained the symmetry thing, just go with that. But refer to @drawoh in the first sentence for the...
So in the end it really depends on the mold maker for how detailed (if any) 2D drawings should be. In the past my drawings have only shown design specific features for the mold (rib thickness, various fillets at the inner corners, draft, threads if they are present, etc.) and locations of any...
Thank you TugboarEng, all great points. I will look into your recommended lubricants.
I would certainly prefer 400 SS, but I am at the mercy of my advisor on this one. After testing, the gear assembly will be used with higher load thus the usage of steel, but yes a smoother material would help...
I am in ME, but have held interviews along with a panel and we all had our questions for the interviewer. I have not heard of anyone using a reference specific to interview questions, though I am sure you can find example questions online. As far as I know, we all have written our own questions...
My advisor has tasked me with finding a grease to use for our gear assembly. The gears are not in a gearbox, thus oil is not ideal. The gears also work at low speeds (on the magnitude of a person's walking gait cycle). Temperatures are also on the magnitude of room temperature (not constantly...
You may want to find a copy of ASME BPVC VIII-1. Appendix 2 is titled "Rules for Bolted Flange Connections with Ring Type Gaskets." Perhaps this is the type of application for your lid. Below is a screen shot of part of the Appendix. PLEASE keep in mind that bolted joint torque calculations can...
And to just close the loop on your overall question:
Runout is not primarily determined by bearing fits (though improper fits will certainly cause issues). The type of chuck used (3 jaw vs 4 jaw) and designs in the lathe that allow for adjustment/calibration is what really contributes to...
As BrianE22 above stated, the only approach I know (and perhaps others know other resources) is to use the manufactures published design rules for tapered bearings.
Just to leave some extra info, non-tapered bearings have a much more straightforward approach. "Roller Bearing Analysis" by Harris...
