Question about units of measure

Question

HI Experts,
I have a scenario -there is a raw material A ( electrical wire), we  purchase it by a rounding number of roll.a roll for 200 MM. And we can't make two short lines for a long line. For example, we need to use 56 MM material A to make a production B. For 3 PCs B,we need a roll.And when we run MRP for product 30 PCs of B, it caculate as 30*56MM/200MM = 8.4,and get a rounding number as 9 rolls.But actually it need 30PCs/(3PCs/roll)=10 rolls.So,it can't suffice the requirement.And I find 2 methods to solve the problem.
1、Use 'Component scrap'  of BOM's item.
2、maitance the quanity of BOM's item  as 0.33 roll
But these 2 methods are not satisfy our user. Can anyone tell me a best solution for this problem?thanks.
thanks very much.
best regards.

Answer 1

Thank you very much,I'm sorry for I do not describe my problem very clearly.
The scenario is actually like this:the material A is an electrical wire and it is very valuable,As we can only  purchase it by a rounding number of roll.a roll for 200 MM. and we can 't use 2 short wires connect as a long wire, such as when we need a material A 50MM,we can only cut a wire which is longer than 50MM  to 50MM for using. And we can't connect 2 wire for using.
Then we need to use the material A to make some products such as finished product B and C,D.The different finished product B,C,D need a different length of material A.take B need 30MM,C need 35MM,D need 85MM as an example.when we make 4 PCs of material D,we need to purchase 2 roll material A.If we using BOM'component scrap,or using "200 mm = 1 roll 1roll = 3pc ",the whole roll is consumed.But in fact after production 4 material D,we still left 2(200mm - 285MM) = 2*30mm material A.It means that we still left 2  piece material A long as 30MM,we can't use it to make material C,but we can use it to make materil B.Is there only solution for this problem?thanks
thanks very much!
best regards!
Dream lee