【转帖】itile block

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titile block
i work for a water pump company to witch i have been assigned the task to create a layout for title block of a three view drawing. right now i have most of the basics but i am looking to see if any one else has any tips on information that i should include. i am looking mainly for opinions of what people have found to work.
any and all help will be greatly appreciated.
thank you,
matt
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perhaps you can list what "basics" you have identified, and then we can suggest what ommissions were made.
but what... is it good for?
engineer at the advanced computing systems division of ibm, 1968, commenting on the microchip.
i'm the one who asked matt to get this info.  i was looking for good practices as it relates to engineering documents, specifically drawings.  most of the standards are incorporated into the 3d programs (like solidworks), but there a great deal of "empiricial" examples of how to prepare for a new company standard (as in our case).  i'm trying to prepare solidworks for a variety of drawings: production, qa, vendor, assembly and even marketing for example.  actually, some of these would ideally be the same drawing but with individual layers (no need to confuse the qa/qc folks with data they don't need or vendors covering two separate operations).  others would need to be separate drawings (general arrangments for customers for example).
i guess i thought there would be some valuable input about the way to set-up drawings to handle a variety of needs and engineering data.
revision control is one of the major problems for all drawings. using seperate layers to show different drawings is going to be a nightmare. say one layer changes and the other don't. do you send a engineering change on all the different drawings even if only one layer changes? change review costs will escalate and vendors will scream.
if your using your drawings for process drawings your drawings may cost you additional cost. say you specify sawing a part and facing on a lathe. say he has the capability to cold saw the part to finished length. i've also machined a valve body in the past where we were performing only one operation. we machined 4 sides of this 14"x14"x5" valve body. two of the holes we machined were valve spool bores and had 21 intersecting holes in each valve spool. without the information about the other holes being in the part our approach to machining this part would have been completely different.i believe in giving all the information when it comes to manufactured parts.
all drawings in my opinion should have its own part number and revision. one of the problems is when do you change a part number? say you add a drilled and tapped hole to a bracket. does the part number change or the revision? unless you work in a totally lean environment, with no inventory, old revision parts will be on the shelf, on order, in transit, or on the dock ready to receive. now do you track inventory by part number and revision or part number only. did purchasing commit to some number of parts for better pricing and cannot change the revision for 3 months? do you have old revision prints available for old revision parts being received in those 3 months?
the engineering side of a drawing change typically is the easy part of the equation. implementation can be a huge headache.
how do you distribute the drawings? electronic format or paper? a welding on a shop floor probably does not have a pc in his weld booth.
food for thought.
reading mil-std-100 is a good start. if you you do any government work, it is most of the time required.
i think asme y14.100-2000 engineering drawing practices has adopted by dod to replaced mil-std-100.
placing different info on several layers would prove to be a bad move as billpsufff"> points out.  something you could do would be to create different sheets of the same drawing with the info for the various departments you are working with.
i worked for one company where the manufacturing info was on the first sheets, with the inspection drawing for qc on the last sheet.  there was a general note that pointed people to sheet x as being for "inspection use only".
but what... is it good for?
engineer at the advanced computing systems division of ibm, 1968, commenting on the microchip.
good input.  the layer idea came to me as i was typing at beer:thirty on friday afternoon as a means to provoke dialogue on various way sto set-up drawings.  i've been thru similar exercises on the right way to set-up part numbers (non-significant seems to be the key) and wanted to take that thru the entire engineering process.  we have moved from a significant part numbering system to non-significant (no, i didn't say insignificant system using 6 digits with 2 check digits (8 total).
i just ordered "engineering documentation control handbook", which is decent.  it discusses the various "documents" that may be used in a business.  
(1)design documents (product specs, part drawing, schematic, etc)
(2)manufacturing docs (process sheets, fixture drawings, qa inspection drawings, etc)
(3)support docs (manuals, spare parts, etc).
it sems to be a sizeable task to make standard templates for each, but i'd like to get most of it taken care of.  also, the disadvantages of significant codes apply to drawings as well, but we use the same drawing for producing parts of differing materials.  therefore drawing numbers need to be common to the part design.
see, you guys in big companies don't have all the headaches....
same form parts but of different material could be handled using a tabulated drawing.
but what... is it good for?
engineer at the advanced computing systems division of ibm, 1968, commenting on the microchip.
genium publishing's modern drafting standards and practices manual is a comprehensive resource, and one that we've used at our company for years.  it was derived from general electric's company standard, and compiles information from ansi, asme, iso, mil, din, and just about any other major standard.  the manual is available through an online subscription at
drafting standards were developed for design engineers and draftsmen and do not consider manufacturing drawings or "process drawings." an example of a process drawing is a flat pattern which makes a formed metal part. the designer really doesn't care what it looks like in process but wants the finished part. some companies require the flat pattern be on the print while other rely on some other system of process drawings.
process drawing usually follow the part design drafting standards and are used just like any other part design drawing. in many cases process drawings are replaced by routing notes such as sawing to a length longer than the print dimension to allow facing stock on the lathe operation. other times process drawings are the design drawings. i have been in a government owned plant where bullets are made by the billions. each step of the process of making the brass casing has an engineering drawing spelling out ever dimension made on the in-process bullet brass.
it depends on the company and how they handle the situation.
ok i warn you before i start. i started to write about setting up manufacturing control drawing system and it kind of ran long.
really the way you want to go about setting up your design system depends on a few things. here are some questions you should ask yourself:
1. what is the complexity of the product you are making?
   a) what is the education level of your machine operators?
   b) are your production employees 'operators' or 'machinist' (in other words, what is there level of expertise?)
   c) how many people does it take to make your customers product.
  if you are making a complex product and there is a large number 'operators' who complete the same step repeatedly? if so then it is probably wise to create some system of manufacturing control (mc) drawings. these drawings will break down a large process into only the part the operator at this operation would need to see. this allows production to quickly train a new operator in his or her job.
  on the other hand if you have a small number well trained employees who work on the same project from start to completion and complete all the steps required then it might not be necessary to create mc drawings.
2. does your customer define tolerances at certain manufacturing steps?
  many internal and external customers define intermediate manufacturing steps. if this is the case then it might be wise to define mc drawings. while a part might meet tolerance on step one it might not be in an optimal position for step two. for example rough machining a part before heat treat. it might be wise to tighten the tolerance of the roughing operation to remove as much material as possible so that when the material is hardened there will be less to machine. for example if the customer called out 2.000±.060 on the rough operation step the mc drawing could call out 1.955±.015. before the mc drawing the tolerance variation on the first step could have been up to .125. that means that the program on your cnc would have to be set up run all parts like they came out of heat treat at 2.060 (not considering any warp in heat treat) that means that if a part on the low end of the tolerance 1.940 came into the machine the first pass or two the machine would not cut anything and would be wasted time.  with the mc drawing we know that all parts are within a tighter range there fore more material is taken away when it is in the annealed state  (hence less when hardened) causing less cycle time as hardened material takes longer to machine than annealed material. the reason i went into this of a specific example is to show specific how manufacturing control tolerancing can directly effect efficiency in manufacturing operations. your customer was mostly likely not thinking about how to get the most out of your specific machines.
3. does you company produce a lot of single product or few of many different products?
  mc drawings would benefit the company that produces a lot of the single product due to the fact that all the expertise and knowledge for making the perfect product could be put onto paper. the time required to make this commitment would result improvements in scrap and efficiency.
  mc drawings would benefit a company that makes small lots of many different parts and rarely makes the same part twice (job shop) due to the fact the time required to make the drawings would not be less than the money/time saved from scrap and efficiency.
here are some other thoughts about mc drawing system:
in a company there is a master print that defines what the part or parts the company is making. that print could be from an external customer or an internal customer. those prints are the prints that quality bases it's final acceptance of the part on. if engineering department decided to setup mc drawings in the manufacturing environment then quality should not be involved in making or releasing of those drawings (aka. they should not have spot to sign on the signature block). it is engineering's job to define the process in the plant not production's nor quality's. one should remember that it is quality job to approve or reject parts based on final acceptance criteria not on intermediate steps. mc drawings should clearly state that they should not be used for final product acceptance.