I'm a student working on a project for college where GD&T is required on the drawings. I thought I had a grasp of it but I'm starting to doubt myself after looking at some examples online from websites and they seem to have less GDT on drawings than I do.
For my drawings so far I have GDT on nearly all my lines. Like for a box type shape on the elevation I would have straightness, flatness and perpendicular/parallel to a datum depending on what line they were to. But the examples I've seen online seem to only have a few and the shapes are more complex.
I'm in the UK so it's ISO standard, any advice/help/tips would be appreciated
Cheers
Trying to get into CNC machining and other aspects of manufacturing (metalworks) in general. These two topics seem to be very important in this respect and I would appreciate detailed explanation of them with practical examples.
Thank you.
I've noticed a lot of schools teach normal rectangular coordinate dimensioning instead of a geometric tolerancing GD&T approach? Is it because simple rectangular is easier to teach?
I have looked everywhere for a copy of this book online, it doesnt seem to exist. Find this and you will be forever known as one of the most feared and exceptional pirates in the world. I will be forever grateful.
I just completed a class (refresher) on GD&T, and the instructor showed a great 20-25min explanation video.
It was made in 1980 by Industrial Media Inc. / Caterpillar.
Does anyone know where I can find it?
*This is just for personal reference & enjoyment.
Title: Fund of Geometric Dimensioning & Tolerancing
Edition: 3^rd
Author: Krulikowski
ISBN: 9781111129828
Publication date: 09 May 2012
It has to be the 3rd edition, the 2nd edition won’t do sadly.
Thanks for any help anybody can give me
I'm looking to brush up on my Geometric Dimensioning and Tolerancing skills, are there any print resources that people could recommend? All the books are on the pricey side so I want to make sure I get a well-written one.
Thanks!
Ok real short story really quick:
I was living in AZ and had a shot to get a job at a really good machinist shot (Modern Industries if anyone is wondering) but I blew the knowledge portion. They were looking for experienced inspectors, and weren't looking to do too much training. I only had a shot as an entry level because my friend and his dad/gramps work there and vouched for me. Well I was getting a little quiz and was doing well until I blew it on the last question. This forced me to move across the country and blah blah blah.
I was hoping someone could help by suggesting some free or low cost resources to bone up on my knowledge in this area. It is, like the title suggests, geometric dimensioning and condition. I want to become proficient in this so I can move back home and get that job.
I'm a QA inspector for a decent size fab shop and I need to teach myself GD&T over the next few months. I started off running press brakes and turrets/lasers and got into the QA department after a few years. The owner started a separate machine shop and I want to move over to that portion of the business because that's where the real money is. But I need to bone up on my knowledge in a hurry. Any resources you guys can point me to would be great! Thanks Reddit!
Does anyone here have any good suggestions for GD&T books? Most of the books I have come across tend to be unclear on the principals. Most of what I have seen tend to just give examples without going into explaining why.
Hello All,
I am already graduated from university and working in the field. I want to learn GD&T, so I picked up a textbook called by Fundamentals of Geometric Dimensioning and Tolerancing, 2E Alex Krulikowski.
There are some nice problems in the book, but I don't have anyone to correct my work for me. Does anyone know where I can find a solution guide?
Is there any free online resource/website to review or practice GD&T drawings?
I want to do the GDTP – 2009 Technologist level test, and I am wondering if any significantly importance from regular 2009 version to the 2018 revised version of the book (even though it has 2009 on it)
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Can someone give me a quick overview of GD&T? I've been looking online but I've been having trouble grasping the concept. And help would be appreciated.
Hello all.
I have recently done my BEng but GD&T wasn't covered. I'd like to learn about it now though.
Do you know of any books that introduce the subject?
I am looking to any kind of reference material that would outlined the expected/possible/achievable geometric tolerance figures for various machining processes.
To be a little more specific about where this request comes from. SKF recommends that bearing housings should have a total runout of less than half of an IT5, which is exceptionally tight (4 microns for the shaft sizes I am working with). I assume that is going to require some additional operations after the initial turning. But would like to know what they might be and if there was some sort of wider reference that covered other tolerances as well then that would help.
Thanks.
Edit: To explain further. I am doing a massive design review and I am initially looking at the ‘special’ features of parts, such as bearing housings.
So while the starting point of looking into machine capability was for the bearing housing runout I am looking to expand this and ideally write some generic design guidelines of the back of what I have found thus far.
I am looking to have a short document that shows the design engineer and the review team which processes are required to achieve certain dimensional/geometric tolerances and surface finishes. I want to avoid over specifying parts by picking an requirement that is just out of reach of normal turning, milling or drilling.
Sure if there is a good reason for needing a vibration polished part to 0.08 Ra then that is what will go on the drawing. But I don’t want to specify something that doesn’t improve the part but makes it considerably more expensive to make.
Hi everyone! I'm having a hard time figuring out this GD&T stuff. I've gone through all of my notes, read my textbook, and searched online. I've got the basics, but this one has me stumped.
Here is the question I'm having trouble with: >Because the positional tolerance includes an MMC modifier, the positional tolerance is subject to a bonus tolerance and defines a virtual condition diameter.
> What is the virtual condition of this diameter?
The drawing is here: http://imgur.com/1tUP9Ck
This is a drawing of a part with two holes, in case that isn't clear.
In this case, since it's a position tolerance, I don't see how it can affect the virtual condition. I know the rules say that virtual condition should be the "worst case" scenario, so for an internal feature like this it should be the MMC (15mm) minus the geometric tolerance (0.01mm) or 14.99mm. Does it work the same in this case? I haven't seen any examples like this yet, so I'm pretty clueless here.
Any help or resources would be much appreciated.
I'm applying GD&T to a spur gear that I've modeled in NX for the first time and this is what I have so far: https://imgur.com/a/Sdhf3b5
I've put arbitrary tolerances for now because I'm a bit confused about how to determine the tolerances for the bore and teeth. From my understanding, if my bore is grade K6, I need a bore tolerance of +2/-7mm according to ISO standards. For the tooth tolerances, I believe I need to reference this CD25 table. Since my reference diameter is 29.91mm, I'm looking at the row that I've highlighted and this is where I'm confused. What does each column correspond to?
I'd appreciate it if anyone could correct any errors I've made, I'm just trying to learn so explanations for my mistakes would be really helpful.
Also, if you have any feedback on my usage of GD&T please share. This is my first time using it after trying to self-study and I'm quite confused still. Thank you.
I work for a 'build to print' shop and have a quick question.
The customer drawing has a linear dimension to a 1/4" plate from a wall. The 1/4" plate is welded to two other 5/8" plates and as you would expect, the 1/4" plate is pretty wavy now. ( _ | _ | _ kind of like this, where the bottom lines are the 1/4" plate [1 plate even though it's 3 lines] and the 2 vertical lines are the 5/8" plate)
Is there a drawing standard that would guide us to an answer as to how much wave is allowed? There is no GD&T on the drawing. Customer specifications don't really address this issue and point to ASME Y14.5 M 1994. That document doesn't seem to address it either, though I am still looking through it. I'm afraid I am almost at a dead end ...
If anyone knows a good place to point me next it would be greatly appreciated.
(Just to throw a wrench at anyone wanting to help me, this is also Nuclear Safety Related ...)
https://imgur.com/a/8ekFMl6
I did this model in blender, but I want to recreate it in FreeCAD because I hope dimensioning will be easier. How do I create such a structure in FreeCAD?
Is it possible to export the graphic in SVG and add text etc., in Inkscape?
I need to indicate the length of twist (long side) as well as the distance between (midpoint) of two of the three conductors (face side). How to best do that?
