Member postings for Mark C

You might find the NSK (RHP Bearings) web site interesting if you want to know more about bearings without getting too technical at first.

http://www.nsk.com/rd/technology.html

Mark

Andrew, which bit of the question/answer would you think we should start with - tribology, metallurgy, material science, transmission/gear design or advanced simulation and modelling?

As Gary points out, the answer to this question is to seek help from his Catia reseller who will no doubt accommodate him with the required training to use these tools confidently. I must also admit to being curious as to how he has managed to get access to that level of software without having the associated support available.

Mark

Having worked with a very experianced engineer in Yorkshire who did a lot of repair shop (machine work) at KWVR, he passed a little gem of information relating to odd sized whit threads being linked to repair work on fire box components (if I remember correctly). He mentioned it as I had been trying to identify an odd whit like thread but with the wrong diameter and I am certain it was 18 or 19 tpi but can't remember much else about it.

I mention this as it would possibly be around the right time historically and if you are in an area that had links to steam engine repairs etc. it might be part of your answer.

Mark

I thought I might add a bit to this - I have read the whole thread (but not all the links) and cannot find any mention to the link between CAD and 3rd angle.

CAD is generally drawn 3rd angle (and I think there is mention of it being preferred in the old BS308) today unless there is a specific reason (locally) to do otherwise. It is done mainly due to a desire to make drawings un-ambiguous as has been stated before - disambiguation is the key to preventing scrap parts and wasted time/money along with recrimination about "who was to fault". As the parts get more complex, the greater the importance of the drawing layout - I have attached a drawing for a part that I drew to give an idea of how a modern CAD drawn part would be produced. It is not complete in the sense that there are a number of extra "sheets" to fully detail it along with a file containing the 3D solid geometry for direct import into the machine center (saved as "as cast" geometry including shrinkage and machining allowances). You will notice the projection information (little cone) and the magic words "if in doubt, ask" which roughley translate to "on your bike, I am making it like this!"

Mark

turns out mine is a number 2 - the motor is out of the arc, probably an old hoover washing machine or the like!

Mark

That is a coincedence! I have one of these that I "rescued" from the local recycling center - I had no idea it was a little brother to the two Elliot mills I have. I will take some pictures and upload them when I get a moment.

Mark

Having had a chuckle at some of the early posts I thought it might be turning into an interesting thread. I would have to agree with Neil above, the main object of a drawing is to convey information in a clear and usefull way. As someone who draws and designs for a living I always try to work the dimension scheme as the operator would work the machine (it's surprising how many shops still work with manual machines).

A lot of the drawings in the mag could be much better presented simply by using a logical datum and working all dimensions from there (particularly helpfull is the use of ordinate dimensions and hole tables).

The down side to this is the need to really have a DRO fitted to the machine so you don't loose track of how far you have gone in any direction!

Mark