balloons or part numbers on assembly drawings
balloons or part numbers on assembly drawings
(OP)
I'm used to seeing balloons with item numbers that link to a table showing the corresponding part number on an assembly drawing. A young lad I hired to do some Solidworks assembly drawings asked why he shouldn't just put the part numbers on the assembly drawing. These days, when it is just as easy to change a CAD drawing as it is to change an Excel spreadsheet, I'm not sure there is any need to use balloons with item numbers over just having the part number on the drawing. Any thoughts?





RE: balloons or part numbers on assembly drawings
Ted
RE: balloons or part numbers on assembly drawings
Who are your assembly technicians?
RE: balloons or part numbers on assembly drawings
RE: balloons or part numbers on assembly drawings
RE: balloons or part numbers on assembly drawings
RE: balloons or part numbers on assembly drawings
Every time you print the same information TWO times on a drawing, you make it possible for ONE of them to be changed at a future date, and not the OTHER. Who ever issued a drawing without it coming back for revisions later? By printing the part number on a leader beside each part call-out, you refer to it once, but then need a list or BOM somewhere else on the drawing to add material details and total quantity. Unless the drawing is so very very simple that this duplication probably won't get missed, then the system of item balloons makes it much easier to track down the instances of each part. Also cuts down on extra text crowded around the assembly view.
Your new guy should also be using the Solidworks features properly. If it's anything like Inventor (people say Inventor is a lot like SW) then it can automatically itemize the BOM, link the item number to each balloon, and when the item balloon's leader arrow touches an object in a view, the properties of that object are detected and linked to the number/letter in the balloon. I started using Inventor last year and this is one of the features that I'm really pleased to have, now. Saves me time.
STF
RE: balloons or part numbers on assembly drawings
RE: balloons or part numbers on assembly drawings
RE: balloons or part numbers on assembly drawings
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:
To an Engineer, the glass is twice as big as it needs to be.
RE: balloons or part numbers on assembly drawings
If you have some kind of ERP/MPR (enterprise/manufacturing resource planning) system (and who doesn't) then you should not duplicate information stored in that database. All you should do is reference it.
Ironically, the half-baked system in use where I currently work does not assign item numbers so I have to use simple descriptions on the drawings.
RE: balloons or part numbers on assembly drawings
These assembly drawings are for the parts manuals that go to the customers. They order parts for repairs from these manuals. Most people that call will give us the part number they need but maybe 3 out of 10 will say they need "item number such-and-such". Then we have to pull out the manual to get the part number.
I played with Solidworks a bit myself yesterday. It does offer an automated ballooning procedure with item numbers. I didn't seen an easy way to write part numbers for each item.
I do like that with a BOM you can add notes to each item number. We don't currently do that but I can see a need for that now.
RE: balloons or part numbers on assembly drawings
It's interesting to read how engineers from different backgrounds and businesses can see things so differently. I left school knowing this stuff, so maybe I go around expecting everyone else to know it!
I use parts manuals and IPC's regularly at work, and they are usually itemized, too. If your customer is referring to "item #" then you can ask for which page or figure in the catalogue, and look it up with that. At your end, the sales orders can include the same page, figure and item number so that there's no confusion. Of course I would expect every one of your agents to have a parts catalog handy for reference, and by referring to it during the phone call can initiate a discussion that confirms that the right part/item has been selected. Many parts catalogs also include, among the first pages, an ordering form or checklist, also to help communicate without errors what part is needed.
Speaking from my experience with Inventor again, when you place a parts list on the drawing, and point it to the assembly that is also illustrated on the drawing, then the parts list is filled automatically with all the part numbers involved in the assembly. They also come in with item numbers, also generated automatically, although they may be in a random order. Then the "housekeeping" begins to sort things out. The point, however, is that the part number, and its material properties, sizes, dimensions etc. have only been defined by the designer only ONCE. All subsequent uses of the data and numbers is linked to the original by SW for you. Not that you can't override it...
STF
RE: balloons or part numbers on assembly drawings
How consistent, unique and sortable are the part numbers on your assembly? You need to look at the part on the assembly and reference it to a line on your parts list. SolidWorks is capable of making your part number and your BOM work. I am not sure this is the best way.
In SolidWorks, I like to sort things so that the fastener sits next to the item it attaches, or at least the first item it attaches. A lot of people try to sort the parts list with the fasteners at the bottom. All of this will be impossible if you sort by part number. Perhaps that is okay for you.
--
JHG
RE: balloons or part numbers on assembly drawings
In my place of business, we have 25 yr old drawings that use part numbers instead of balloon callouts. We have had first hand issues missing parts on more complex assemblies.
-Dustin
Professional Engineer
Pretty good with SolidWorks
RE: balloons or part numbers on assembly drawings
In that case I can see the attraction of putting the actual part number and not having a parts list as such. Total qty for BOM generation may not be particularly relevant. Our cad system can dynamically call out the indicated components part number which minimizes the issues from listing something multiple times.
However, for a true engineering assy drawing I'd tend to stick with balloons.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: balloons or part numbers on assembly drawings
I say go with balloons for several reasons:
1. They are the correct drafting practice
2. Balloons with a single BOM minimizes duplication and chances for errors. My CAD system can call out baloons or part numbers linked to the model, but reason #1 overrides that.
3. The drawing is much cleaner
4. I chain balloons when calling out a part and fasteners. Using part numbers would quickly clutter the drawing
5. Adding quanities under each part number rather than under a baloon creates clutter.
6. If you don't have a dynamic link between the baloons and BOM, it's much easier to see an item number in a balloon to check against the BOM than it is to see part numbers all over the page.
Kyle