Tolerance stack analysis
Tolerance stack analysis
(OP)
Hello i am a little new to engineering and i have just been asked to do a tolerance stack analysis on a project i am working on.
Attched is a picture that shows a machined from solid chassis with two steps in it, on the top step PCB-2 is fixed and on the bottom step PCB-4 is fixed.
On the base of the box there is a raised section which PART-2 sits and terminates at the top toPCB-4, on the right of Part-2 is PART-2 this sits slightly lower in the chassis and its terminals are connect to PCB-4 through SPACER-3.
On the top face of PCB-2 and PCB-4 is another PCB (PCB-1 & PCB3) mounted on spacers (sopacer-1 and spacer 2)
.
Could sombody please show me an example of how to do a toleance stack on this.
Datum would be from the top of the chassis i think??
Chassis tolerance = +/-0.15
spacers +/- 0.1
part-2 +/- 0.2
part-1 +/- 0.25
pcb-1,2,3 & 4 +/- 0.3
Thank you, any help would be very much appresiated.
Attched is a picture that shows a machined from solid chassis with two steps in it, on the top step PCB-2 is fixed and on the bottom step PCB-4 is fixed.
On the base of the box there is a raised section which PART-2 sits and terminates at the top toPCB-4, on the right of Part-2 is PART-2 this sits slightly lower in the chassis and its terminals are connect to PCB-4 through SPACER-3.
On the top face of PCB-2 and PCB-4 is another PCB (PCB-1 & PCB3) mounted on spacers (sopacer-1 and spacer 2)
.
Could sombody please show me an example of how to do a toleance stack on this.
Datum would be from the top of the chassis i think??
Chassis tolerance = +/-0.15
spacers +/- 0.1
part-2 +/- 0.2
part-1 +/- 0.25
pcb-1,2,3 & 4 +/- 0.3
Thank you, any help would be very much appresiated.





RE: Tolerance stack analysis
Try to perform a web search on tolerance analysis, where you will be able to see some examples.
RE: Tolerance stack analysis
Could you please expand on what I have missing?? Like I said I am new to this stuff.
Thank you.
RE: Tolerance stack analysis
Thank you.
RE: Tolerance stack analysis
You need to have detailed drawings of all the parts.
desertfox
RE: Tolerance stack analysis
No engineering drawing have been produced yet, it's just a concept at this stage.
RE: Tolerance stack analysis
We can't guess what the figures might be even for an example,for instance if you think PCB 4 will rest on the chassis and on spacer 3 which might hold part 1 to the chassis then think again.
We need to understand which components need to rest on what and whats important in terms of its relationship with the other components.
desertfox
RE: Tolerance stack analysis
Parts 1 & 2 are fixed to the chassis base then, spacer-3 (metal m/f spacer) will be fitted to part-1, pcb-4 will then be fixed to the lower chassis step, then part-2 and spacer-3 will be secured from the top side of pcb-4 using screws, flat washer and wavey washers.
Hope this makes it more clear ?
Thank You.
RE: Tolerance stack analysis
Most anyone on this forum can perform the analysis for you, but that is not what this forum is about, nor what you asked.
I performed a web search, and third link down was this one:
http://adcats.et.byu.edu/Publication/87-5/WAM2.html
Is that example inadequate?
It seems to have the "how to instructions" you are looking for.
RE: Tolerance stack analysis
RE: Tolerance stack analysis
RE: Tolerance stack analysis
Drafting Standards, GD&T & Tolerance Analysis may be a better place for such questions in future.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Tolerance stack analysis