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Change hole standard

Hello all. I may be opening a can of worms :smileyhappy: However I could use a suggestion please.

     Has anyone come across a program or tool to change the hole standard in an existing design.

We have some existing designs that we need to update to new company standards. The existing designs had Ansi fasteners and need to be updated to Metric fasteners. I am not sure if the revised hole command and features in ST7 make this easier to accomplish or more difficult. 

Any input or suggestions are appreciated.

 

Jason Smith

STM Manufacturing

2 REPLIES

Re: Change hole standard

One feature that helps is "replace part"

But depending on how your model is created you have a lot of manual editing to do.

 

For example, if you have ordered sketch hole cuts for couplings, bungs, strucutral memebers, etc that will all become a differant size. Thoes parts of the model will need to be edited manually.

 

Converting to metric parts is not an easy undertaking.

 

One decision you should make right off is are you going to work in english units with soft metric or are you going to work in metric with soft english. IE are metric units or english units in control of the design. Another way to look at this is. Either 1"=2.54 cm OR 1cm = 0.393701"

Pick one set of conversions and stick with it.

 

Test your methods of dimension display and set up dimension style before you start making drawings. I'm assuming you now need to use dual units to satisfy a shop using english tools for a client outside the US who only understand metric.

 

 

Re: Change hole standard

Hello Jason,

The first question you should ask yourself is "will I need to support existing customer and send them part for ANSI fastener".
Even if the answer is "not sure" or "no", there is basic rules to decide if you revise a part or if you need to create a new part number.

This is called "Form, Fit and Function".
If you plan to use the new part (metric hole) on existing "old" design, you will need to make sure it will fit in both old and new scenarios.
My guess is that you may find it easier, in a long term perspective, to create new part number for metric part.
It will simplify the management of all this.

Many years ago, in a previous job I had, I was not aware of that "Form, Fit and Function" stuff.
Than, I've revised some parts just looking forward and forgot to think, that at some point, customer will need to ask for spare parts.
This lead to a lot of extra work for documentation.
Just imagine.  You have to specify in your parts list that before serial number "xx", you need to order Part_A at revision 5 and not at the current revision.
This also create extra work into the ERP system to "force" order of "Part_A REV-5" (even if inventory tells me that there were enough parts in stock).

For sure, you may end up using macro to copy and update hole, feature and fastener.

My point here is just to make you think twice before simply changing hole diameter or thread feature.

Hope this will help you a little bit.

Regards,


Michel Corriveau