Help with Co-Part Set Up

Sorry - bit of a long one…

I need a bit of help revising some parts/co-parts as we’ve discovered that our new tools are not as we thought. These are make-to-order parts.

I have 2 tools generating 6 parts:
• 302010
• 302012
• 302013
• 302014
• 921015-a
• 921015-b

Parts 302010/12/13/14 are all sold individually, however it is normal that they are ordered together and in the same quantity. Parts 921015-a and 921015-b are assembled to create 921015 which is the saleable part. Part 921015 is not always ordered at the same time as the 302010 range.

Tool 1 produces:
• 3 x Part 302010
• 1 x Part 921015-a

Tool 2 produces:
• 1 x Part 302012
• 1 x Part 302013
• 1 x Part 302014
• 1 x Part 921015-b

It is not possible to configure the tools so that only certain parts are made at a time – they are all made when the tool is run.

How do I go about setting up these parts/co-parts so that Jobs are created correctly from Sales Orders? I assume that any co-parts manufactured that are not required for the Sales Order would just be booked to inventory?

Thanks in advance.

Hi Emily,

I have a couple of questions for you:

  1. How are the parts set up in Part Maintenance? Are they stock or non-stock?

  2. Is there a separate MOM to assemble part 921015-a and 921015-b with these parts listed as a material or are the methods to create these parts in the same method as the saleable part (921015)?

Hi Beth,

Thanks for you time.

  1. They are currently set up as non-stock.
  2. We don’t currently have a MOM to combine parts a & b. The original understanding was that 1 tool made both parts, so the assembly just got rolled up into the moulding operation.

Hope this makes sense.

Hi Emily,

This makes perfect sense to me. I work for an injection molding company, so I really understand!

With having the parts non-stock, that will raise issues with MRP if you have parts already in stock because it won’t look at those (the parts are make-to-order, not make-to-stock). As long as your order entry people know to check inventory when the customer places the order and change the line to pull from the stock quantity, you won’t have a problem but there is nothing to alert them that there is a stock of these parts. Does that make sense?

For the 921015 series of parts, if you sell part 921015 but don’t have a method to manufacture it, how do you fulfill the order (especially since it is a make-to-order part)? What I have done here is to make a method for the top-level part with an operation of Assembly. Part 921015-a and 921015-b would be the materials and would be set up as stocked parts. They are picked to the job to manufacture 921015.

To set up co-parts for each tool, decide which part will be the “parent” and which part(s) will be the “child(ren)”. The parent part will have all the material included for the entire shot (resin, components and inserts). I put a note in the Operation comments that tells the operator how many of each manufactured part are included in a shot and if any of these parts requires inserts and/or components, how many are required and what part they go into. Does this make sense?

In Engineering Workbench, on the Revision > Co Parts > Detail tab, fill in the fields:
If 921015-a is the “parent” part -
the yield per would be 1
the material cost factor would be ((part weight + 1/4 runner weight) / total shot weight) * 100
example: total shot weight is 40, part weight is 8 grams, runner is 8 grams
((8 + 2) / 40) * 100) = 25
Note: If there are inserts or components in this part, this formula to get the cost factor is different
the labor cost factor would be 1 (25% of the labor cost and burden cost)
check the Primary Costing checkbox
then 302010 would be the “child” part -
the yield per would be 3
the material cost factor would be (((part weight * 3) + 3/4 runner weight) / total shot weight) * 100
example: total shot weight is 40, part weight is 8, runner is 8 grams
(((8 * 3) + 6) / 40) * 100) = 75
Note: If there are inserts or components in this part, this formula to get the cost factor is different
the labor cost factor would be 3 (75% of the labor cost and burden cost)
check the Prevent suggestions checkbox

In the Method of Manufacturing, add the molding operation. Qty/Parent would be 1. Prod Std would be 3600 / cycle time.
Add the total shot weight for the material and any planned scrap. Add information on the parts to Manufacturing comments, such as how many of each per shot.

The child part’s MOM is blank and unapproved so it won’t give you double suggestions.

I hope this helps.

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