Use of Sales BOM to force ATP against Bulk Material?

Question

Background:
Our business was recently acquired, and we have migrated to the parent company's R/3 system.  In our previous MRP system (R/2), we planned, produced, and shipped a single bulk Material ID in Trucks, Rail Cars, Flexi-Bags, and Iso-Tainers.  In the new system, specific Material IDs are now required for each of these modes.  However, we do not store the inventory in these modes, nor do we wish to plan at this detailed level.
Considered So Far:
Initial suggestion was to use A.T.O. to look through a BOM and automatically create production orders for each customer order. However, this seems to add additional complexity that we do not really need, and makes changing order dates more challenging (have to move both the order and the accompanying Prod. Order).
Desired Outcome:
Order is entered and priced based upon the mode-specific Material ID, but inventory is relieved from the Bulk material.  In our previous R/2 system, there was a field on the material master called "Std.Prod." which stood for Standard Product Link.  We used it for synonymous products where we produced and inventoried under one name, but sold under several different names.  The customer materials were set up as type SALE and referenced the inventoried material, set as type FINI, in this Std. Prod. field.  Thus, at the header level, the user saw the SALE material, but for planning and at the batch level, the system showed the FINI.
Options?
I am told that, due to the amount of custom coding and user exits surrounding outputs and interfaces to EDI and other external systems, the use of Material Determination would require too much testing and potentially too much development work.  But, is it the best / correct solution to the problem?  Because right now, I don't have the ability to perform ATP against the inventoried Material, so nothing confirms.  Would the use of a 1 to 1 Sales BOM offer anything different?
Many Thanks in Advance,
J.P.

Answer 1

Hello JP
Material Determination (MD) works with Consignment orders, only you need to assign a MD procedure to the requisite sales document type in config ( TO code OV14). Product substitution, which is a specialized form of MD, makes use of special item cats like TAX and TAPS or TAPA and TAN for main and substitute items respectively, but you can always make copies of them and use them with consignment orders also in conjunction with item category usages like PSHP. PSEL, PSA1 and PSA2. There could be resultant issues, but unless you test you won't know them all.
Your second question about 'Sale would go against the finished good (Truck / Rail material) while the production costs go against the Bulk', brought a new realization in me. You are ordering, pricing and delivering Truck or Rail materials, but those requirements have to be converted to Production orders for bulk material, so from a Sales and Distribution (SD) point of view you  don't need anything extra, therefore work with you Production Planning (PP) consultant to convert the requirements at  PP end?? May be without resorting to MD or BOMs in Sales, you can work with your PP consultant and with standard config or custom development, you may realize your desired outcome.
Also as long as cost is maintained in the sales Material (Truck for example)  with due regard to the additional costs in converting Bulk to truck, you should be fine. Follow the example below:
Standard cost of 1 ton , say X, is stored in Bulk Material master.
Now if there is no additional cost and you just load the bulk material into a truck and if a Truck is 10 ton, then Truck material would have 10X in its material master for cost.
But if there is some other material  and/or  labor involved in converting bulk to Truck and their cost is y, then you will have (10x+y) in your truck material. Also it is worthwhile to capture the additional cost in the Production/Assembly order via components and operations.
Your problem is not insurmountable, but you need to assemble a team of SD. PP, MM and CO experts to design an integrated solution for you.