Backward Scheduling to Include Extra Parts

Yahoo Archive
1
Then you end up with 6 'extra' good pieces in stock (unless you want to articially scrap them just so the loss is rolled into job cost and you end up with no inventory to carry).

Wouldn't you be better off focusing on how to foolproof your processes so you don't incur the scrap (versus trying to figure out a way to complicate your planning and system processes to compensate for the scrap)?

Who do you want to be? General Motors, Chrysler, Ford (MRP II and heading towards bankruptcy) or Toyota, Honda, Nissan, etc., (reliable value-added Lean processes, simple ERP processes as a result - and profitable).

More complex computer models aren't the goal, they are a non-value added cost.

Rob

--- On Wed, 11/19/08, Ari Footlik <ari@...> wrote:

From: Ari Footlik <ari@...>
Subject: RE: [Vantage] Re: Backward Scheduling to Include Extra Parts
To: vantage@yahoogroups.com
Date: Wednesday, November 19, 2008, 1:39 PM






Thanks. I was considering this, but my question in this case is:

What happens if we end up making 6 good pcs and none of the extra 6 get
scrapped?

--Ari

____________ _________ _________ __

From: vantage@yahoogroups .com [mailto:vantage@yahoogroups .com] On Behalf
Of gsc1161
Sent: Wednesday, November 19, 2008 12:31 PM
To: vantage@yahoogroups .com
Subject: [Vantage] Re: Backward Scheduling to Include Extra Parts

You can set a scrap factor at each component on the assemblies
method, so that MRP see "extra" demand for the component. The scrap
factor can be a fixed quantity, or a % of the assembly quantity.

--- In vantage@yahoogroups .com <mailto:vantage% 40yahoogroups. com> , "Ari
Footlik" <ari@...> wrote:
>
> I just realized that there is an opportunity to greatly improve our
> scheduling of jobs. Specifically, what I realized is that for
every job
> we always plan to make (and actually make) extra pieces, but we do
this
> without informing Vantage we're going to do it.
>
> For example, we have an order for 50 pcs and we know we're going to
make
> 56 pieces (just-in-case) , but the order in Vantage tied to the job
is
> for only those original 50 pcs. Therefore, the backward scheduling
is
> done only for 50 pcs, and there is no allowance in the schedule for
the
> extra pieces we *know* we're going to run. Even in the best case,
then,
> where we hit the target minutes/piece, we'll still blow the schedule
> because we took the time to make 6 extra pieces!
>
> So, what is the best way to include these extra pieces in the
> scheduling? Do we do add a "Make to Stock" demand for the job (if
we
> scrap some of the 6, won't we get an "under-quantity" warning)? Or
do
> we add 6 pcs of scrap to each operation (would we have to add it to
> every op, or just the first and it'd carry through)? Is there
another
> option I'm not seeing?
>
> Thanks!
> --Ari
>

[Non-text portions of this message have been removed]
2
I just realized that there is an opportunity to greatly improve our
scheduling of jobs. Specifically, what I realized is that for every job
we always plan to make (and actually make) extra pieces, but we do this
without informing Vantage we're going to do it.

For example, we have an order for 50 pcs and we know we're going to make
56 pieces (just-in-case), but the order in Vantage tied to the job is
for only those original 50 pcs. Therefore, the backward scheduling is
done only for 50 pcs, and there is no allowance in the schedule for the
extra pieces we *know* we're going to run. Even in the best case, then,
where we hit the target minutes/piece, we'll still blow the schedule
because we took the time to make 6 extra pieces!

So, what is the best way to include these extra pieces in the
scheduling? Do we do add a "Make to Stock" demand for the job (if we
scrap some of the 6, won't we get an "under-quantity" warning)? Or do
we add 6 pcs of scrap to each operation (would we have to add it to
every op, or just the first and it'd carry through)? Is there another
option I'm not seeing?

Thanks!
--Ari
3
You can set a scrap factor at each component on the assemblies
method, so that MRP see "extra" demand for the component. The scrap
factor can be a fixed quantity, or a % of the assembly quantity.


--- In vantage@yahoogroups.com, "Ari Footlik" <ari@...> wrote:
>
> I just realized that there is an opportunity to greatly improve our
> scheduling of jobs. Specifically, what I realized is that for
every job
> we always plan to make (and actually make) extra pieces, but we do
this
> without informing Vantage we're going to do it.
>
> For example, we have an order for 50 pcs and we know we're going to
make
> 56 pieces (just-in-case), but the order in Vantage tied to the job
is
> for only those original 50 pcs. Therefore, the backward scheduling
is
> done only for 50 pcs, and there is no allowance in the schedule for
the
> extra pieces we *know* we're going to run. Even in the best case,
then,
> where we hit the target minutes/piece, we'll still blow the schedule
> because we took the time to make 6 extra pieces!
>
> So, what is the best way to include these extra pieces in the
> scheduling? Do we do add a "Make to Stock" demand for the job (if
we
> scrap some of the 6, won't we get an "under-quantity" warning)? Or
do
> we add 6 pcs of scrap to each operation (would we have to add it to
> every op, or just the first and it'd carry through)? Is there
another
> option I'm not seeing?
>
> Thanks!
> --Ari
>
4
Or, if you don't want to do this (many components), creat another
parent assembly, with the original parent structured to this one, and
put a scrap factor on this new "component" -- Demand would have to be
changed to the new parent assembly number, but it would then flow
down to the single, former assembly, with added scrap quantities.

--- In vantage@yahoogroups.com, "gsc1161" <gcreighton@...> wrote:
>
> You can set a scrap factor at each component on the assemblies
> method, so that MRP see "extra" demand for the component. The
scrap
> factor can be a fixed quantity, or a % of the assembly quantity.
>
>
> --- In vantage@yahoogroups.com, "Ari Footlik" <ari@> wrote:
> >
> > I just realized that there is an opportunity to greatly improve
our
> > scheduling of jobs. Specifically, what I realized is that for
> every job
> > we always plan to make (and actually make) extra pieces, but we
do
> this
> > without informing Vantage we're going to do it.
> >
> > For example, we have an order for 50 pcs and we know we're going
to
> make
> > 56 pieces (just-in-case), but the order in Vantage tied to the
job
> is
> > for only those original 50 pcs. Therefore, the backward
scheduling
> is
> > done only for 50 pcs, and there is no allowance in the schedule
for
> the
> > extra pieces we *know* we're going to run. Even in the best
case,
> then,
> > where we hit the target minutes/piece, we'll still blow the
schedule
> > because we took the time to make 6 extra pieces!
> >
> > So, what is the best way to include these extra pieces in the
> > scheduling? Do we do add a "Make to Stock" demand for the job
(if
> we
> > scrap some of the 6, won't we get an "under-quantity" warning)?
Or
> do
> > we add 6 pcs of scrap to each operation (would we have to add it
to
> > every op, or just the first and it'd carry through)? Is there
> another
> > option I'm not seeing?
> >
> > Thanks!
> > --Ari
> >
>
5
Thanks. I was considering this, but my question in this case is:

What happens if we end up making 6 good pcs and none of the extra 6 get
scrapped?

--Ari

________________________________

From: vantage@yahoogroups.com [mailto:vantage@yahoogroups.com] On Behalf
Of gsc1161
Sent: Wednesday, November 19, 2008 12:31 PM
To: vantage@yahoogroups.com
Subject: [Vantage] Re: Backward Scheduling to Include Extra Parts



You can set a scrap factor at each component on the assemblies
method, so that MRP see "extra" demand for the component. The scrap
factor can be a fixed quantity, or a % of the assembly quantity.

--- In vantage@yahoogroups.com <mailto:vantage%40yahoogroups.com> , "Ari
Footlik" <ari@...> wrote:
>
> I just realized that there is an opportunity to greatly improve our
> scheduling of jobs. Specifically, what I realized is that for
every job
> we always plan to make (and actually make) extra pieces, but we do
this
> without informing Vantage we're going to do it.
>
> For example, we have an order for 50 pcs and we know we're going to
make
> 56 pieces (just-in-case), but the order in Vantage tied to the job
is
> for only those original 50 pcs. Therefore, the backward scheduling
is
> done only for 50 pcs, and there is no allowance in the schedule for
the
> extra pieces we *know* we're going to run. Even in the best case,
then,
> where we hit the target minutes/piece, we'll still blow the schedule
> because we took the time to make 6 extra pieces!
>
> So, what is the best way to include these extra pieces in the
> scheduling? Do we do add a "Make to Stock" demand for the job (if
we
> scrap some of the 6, won't we get an "under-quantity" warning)? Or
do
> we add 6 pcs of scrap to each operation (would we have to add it to
> every op, or just the first and it'd carry through)? Is there
another
> option I'm not seeing?
>
> Thanks!
> --Ari
>






[Non-text portions of this message have been removed]
6
Ari...just to be sure I understand your question...

Are you looking for a way to make the Job Head Production Qty be >
than the demand qty? Or are you looking for a way to increase the
production qty at an operation?

Either way, it all depends on what you plan for on your first
operations. You do this by making the qty/parent of the operation to
be > 1.00. It then multiplies the qty/per by the parent qty to come
up with a higher yield for that operation. If the first couple
operations are planned to produce more, than it trickles down through
the operations.

But know that if you don't plan for it all the way through,
efficiencies will look lower as you are running through more product
to complete the operation in the hopes that you can "sell" the extra
qty.

Patty Buechler

--- In vantage@yahoogroups.com, "Ari Footlik" <ari@...> wrote:
>
> Thanks. I was considering this, but my question in this case is:
>
> What happens if we end up making 6 good pcs and none of the extra 6
get
> scrapped?
>
> --Ari
>
> ________________________________
>
> From: vantage@yahoogroups.com [mailto:vantage@yahoogroups.com] On
Behalf
> Of gsc1161
> Sent: Wednesday, November 19, 2008 12:31 PM
> To: vantage@yahoogroups.com
> Subject: [Vantage] Re: Backward Scheduling to Include Extra Parts
>
>
>
> You can set a scrap factor at each component on the assemblies
> method, so that MRP see "extra" demand for the component. The scrap
> factor can be a fixed quantity, or a % of the assembly quantity.
>
> --- In vantage@yahoogroups.com <mailto:vantage%
40yahoogroups.com> , "Ari
> Footlik" <ari@> wrote:
> >
> > I just realized that there is an opportunity to greatly improve
our
> > scheduling of jobs. Specifically, what I realized is that for
> every job
> > we always plan to make (and actually make) extra pieces, but we
do
> this
> > without informing Vantage we're going to do it.
> >
> > For example, we have an order for 50 pcs and we know we're going
to
> make
> > 56 pieces (just-in-case), but the order in Vantage tied to the
job
> is
> > for only those original 50 pcs. Therefore, the backward
scheduling
> is
> > done only for 50 pcs, and there is no allowance in the schedule
for
> the
> > extra pieces we *know* we're going to run. Even in the best case,
> then,
> > where we hit the target minutes/piece, we'll still blow the
schedule
> > because we took the time to make 6 extra pieces!
> >
> > So, what is the best way to include these extra pieces in the
> > scheduling? Do we do add a "Make to Stock" demand for the job (if
> we
> > scrap some of the 6, won't we get an "under-quantity" warning)?
Or
> do
> > we add 6 pcs of scrap to each operation (would we have to add it
to
> > every op, or just the first and it'd carry through)? Is there
> another
> > option I'm not seeing?
> >
> > Thanks!
> > --Ari
> >
>
>
>
>
>
>
> [Non-text portions of this message have been removed]
>
7
What I'm really looking for is the right way to make sure that the
backward scheduling takes into account the fact that we'll be making
more than the demand, which I guess means I want the Production Qty to
be greater than the Demand (Order) Qty.

If we think of larger numbers, say, Order Qty. 70000, we're more likely
going to make 74000. Let's say it we can make 2000 pcs per day. If we
have Production Qty set at 70000, the scheduling process will determine
that it should count backward 35 days. But in reality, it will actually
take us 37 days to make all 74000, so we will overrun the production
window by 2 days.

I suppose another way to think about it is this: We assume that
throughout the entire job (including all operations), we'll end up
scrapping up to 4000 pcs at various stages of production; we just don't
know in advance which operations will result in how much scrap.

Does that make any sense?
--Ari

________________________________

From: vantage@yahoogroups.com [mailto:vantage@yahoogroups.com] On Behalf
Of bpbuechler
Sent: Wednesday, November 19, 2008 1:02 PM
To: vantage@yahoogroups.com
Subject: [Vantage] Re: Backward Scheduling to Include Extra Parts



Ari...just to be sure I understand your question...

Are you looking for a way to make the Job Head Production Qty be >
than the demand qty? Or are you looking for a way to increase the
production qty at an operation?

Either way, it all depends on what you plan for on your first
operations. You do this by making the qty/parent of the operation to
be > 1.00. It then multiplies the qty/per by the parent qty to come
up with a higher yield for that operation. If the first couple
operations are planned to produce more, than it trickles down through
the operations.

But know that if you don't plan for it all the way through,
efficiencies will look lower as you are running through more product
to complete the operation in the hopes that you can "sell" the extra
qty.

Patty Buechler

--- In vantage@yahoogroups.com <mailto:vantage%40yahoogroups.com> , "Ari
Footlik" <ari@...> wrote:
>
> Thanks. I was considering this, but my question in this case is:
>
> What happens if we end up making 6 good pcs and none of the extra 6
get
> scrapped?
>
> --Ari
>
> ________________________________
>
> From: vantage@yahoogroups.com <mailto:vantage%40yahoogroups.com>
[mailto:vantage@yahoogroups.com <mailto:vantage%40yahoogroups.com> ] On
Behalf
> Of gsc1161
> Sent: Wednesday, November 19, 2008 12:31 PM
> To: vantage@yahoogroups.com <mailto:vantage%40yahoogroups.com>
> Subject: [Vantage] Re: Backward Scheduling to Include Extra Parts
>
>
>
> You can set a scrap factor at each component on the assemblies
> method, so that MRP see "extra" demand for the component. The scrap
> factor can be a fixed quantity, or a % of the assembly quantity.
>
> --- In vantage@yahoogroups.com <mailto:vantage%40yahoogroups.com>
<mailto:vantage%
40yahoogroups.com> , "Ari
> Footlik" <ari@> wrote:
> >
> > I just realized that there is an opportunity to greatly improve
our
> > scheduling of jobs. Specifically, what I realized is that for
> every job
> > we always plan to make (and actually make) extra pieces, but we
do
> this
> > without informing Vantage we're going to do it.
> >
> > For example, we have an order for 50 pcs and we know we're going
to
> make
> > 56 pieces (just-in-case), but the order in Vantage tied to the
job
> is
> > for only those original 50 pcs. Therefore, the backward
scheduling
> is
> > done only for 50 pcs, and there is no allowance in the schedule
for
> the
> > extra pieces we *know* we're going to run. Even in the best case,
> then,
> > where we hit the target minutes/piece, we'll still blow the
schedule
> > because we took the time to make 6 extra pieces!
> >
> > So, what is the best way to include these extra pieces in the
> > scheduling? Do we do add a "Make to Stock" demand for the job (if
> we
> > scrap some of the 6, won't we get an "under-quantity" warning)?
Or
> do
> > we add 6 pcs of scrap to each operation (would we have to add it
to
> > every op, or just the first and it'd carry through)? Is there
> another
> > option I'm not seeing?
> >
> > Thanks!
> > --Ari
> >
>
>
>
>
>
>
> [Non-text portions of this message have been removed]
>






[Non-text portions of this message have been removed]
8
Actually it does make sense.

We plan for more qty on the first few operations (Qty/Parent > 1.00);
therefore the next operation receives more than what they are planned
to receive. We do, at some point of the job, determine if final
product overs is accepted. If it is, then all operations are told
produce everything they are given. If it is not accepted, then we
enter that qty as scrap at the point where we stop (prior to the next
operation).

Quality, Inventory, and Finance has great issues with this. First
of...you are shooting yourself in the foot in regards to Lean
Manufacturing. Secondly...Inventory needs to deal (discard) with the
overs. Thirdly...the cost of producing the overs up to a certain
point is extremely difficult to reconcile (planned overs and
unplanned overs).

But I do get the real world business case...
The arguing factors of the cost of producing overs that you
potentially do not complete through the end product or the inability
to recoop the cost and sell the overs to the customer[s]...is a hard
sell when you are aspiring to be lean;)

Thanks
Patty Buechler


--- In vantage@yahoogroups.com, "Ari Footlik" <ari@...> wrote:
>
> What I'm really looking for is the right way to make sure that the
> backward scheduling takes into account the fact that we'll be making
> more than the demand, which I guess means I want the Production Qty
to
> be greater than the Demand (Order) Qty.
>
> If we think of larger numbers, say, Order Qty. 70000, we're more
likely
> going to make 74000. Let's say it we can make 2000 pcs per day.
If we
> have Production Qty set at 70000, the scheduling process will
determine
> that it should count backward 35 days. But in reality, it will
actually
> take us 37 days to make all 74000, so we will overrun the production
> window by 2 days.
>
> I suppose another way to think about it is this: We assume that
> throughout the entire job (including all operations), we'll end up
> scrapping up to 4000 pcs at various stages of production; we just
don't
> know in advance which operations will result in how much scrap.
>
> Does that make any sense?
> --Ari
>
> ________________________________
>
> From: vantage@yahoogroups.com [mailto:vantage@yahoogroups.com] On
Behalf
> Of bpbuechler
> Sent: Wednesday, November 19, 2008 1:02 PM
> To: vantage@yahoogroups.com
> Subject: [Vantage] Re: Backward Scheduling to Include Extra Parts
>
>
>
> Ari...just to be sure I understand your question...
>
> Are you looking for a way to make the Job Head Production Qty be >
> than the demand qty? Or are you looking for a way to increase the
> production qty at an operation?
>
> Either way, it all depends on what you plan for on your first
> operations. You do this by making the qty/parent of the operation
to
> be > 1.00. It then multiplies the qty/per by the parent qty to come
> up with a higher yield for that operation. If the first couple
> operations are planned to produce more, than it trickles down
through
> the operations.
>
> But know that if you don't plan for it all the way through,
> efficiencies will look lower as you are running through more
product
> to complete the operation in the hopes that you can "sell" the
extra
> qty.
>
> Patty Buechler
>
> --- In vantage@yahoogroups.com <mailto:vantage%
40yahoogroups.com> , "Ari
> Footlik" <ari@> wrote:
> >
> > Thanks. I was considering this, but my question in this case is:
> >
> > What happens if we end up making 6 good pcs and none of the extra
6
> get
> > scrapped?
> >
> > --Ari
> >
> > ________________________________
> >
> > From: vantage@yahoogroups.com <mailto:vantage%40yahoogroups.com>
> [mailto:vantage@yahoogroups.com <mailto:vantage%
40yahoogroups.com> ] On
> Behalf
> > Of gsc1161
> > Sent: Wednesday, November 19, 2008 12:31 PM
> > To: vantage@yahoogroups.com <mailto:vantage%40yahoogroups.com>
> > Subject: [Vantage] Re: Backward Scheduling to Include Extra Parts
> >
> >
> >
> > You can set a scrap factor at each component on the assemblies
> > method, so that MRP see "extra" demand for the component. The
scrap
> > factor can be a fixed quantity, or a % of the assembly quantity.
> >
> > --- In vantage@yahoogroups.com <mailto:vantage%40yahoogroups.com>
> <mailto:vantage%
> 40yahoogroups.com> , "Ari
> > Footlik" <ari@> wrote:
> > >
> > > I just realized that there is an opportunity to greatly improve
> our
> > > scheduling of jobs. Specifically, what I realized is that for
> > every job
> > > we always plan to make (and actually make) extra pieces, but we
> do
> > this
> > > without informing Vantage we're going to do it.
> > >
> > > For example, we have an order for 50 pcs and we know we're
going
> to
> > make
> > > 56 pieces (just-in-case), but the order in Vantage tied to the
> job
> > is
> > > for only those original 50 pcs. Therefore, the backward
> scheduling
> > is
> > > done only for 50 pcs, and there is no allowance in the schedule
> for
> > the
> > > extra pieces we *know* we're going to run. Even in the best
case,
> > then,
> > > where we hit the target minutes/piece, we'll still blow the
> schedule
> > > because we took the time to make 6 extra pieces!
> > >
> > > So, what is the best way to include these extra pieces in the
> > > scheduling? Do we do add a "Make to Stock" demand for the job
(if
> > we
> > > scrap some of the 6, won't we get an "under-quantity" warning)?
> Or
> > do
> > > we add 6 pcs of scrap to each operation (would we have to add
it
> to
> > > every op, or just the first and it'd carry through)? Is there
> > another
> > > option I'm not seeing?
> > >
> > > Thanks!
> > > --Ari
> > >
> >
> >
> >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>
>
>
>
> [Non-text portions of this message have been removed]
>
9
If you are confident about your yield losses, (example - you ALWAYS lose 2 pc's to set up a specific part on a CNC machine) - put it right in the pertinent OPs in your methods. (Specify the typical yield within the OP.)

If your not (but still semi-confident enough to tell your planners/job-schedulers to usesome 'rule of thumb' rules to preplan a little extra overproduction) - add the extra qty as make to stock.

It won't create extra work if you also then set up your resources to enable them for the yield recalc process. Turn on yield recalc in company set up. (I think it is also a recurring process or system BPM that must be activated... Can't remember as we set it up a long time ago.)

All your OPs must be time & qty reporting for yield qty recalc to work.

As your people report scrap qty at an OP, the process detects it and reduces the total job qty (make to stock first, make to job or order next) by that amount so the global scheduler allocates less capacity to remaining Ops that follow.

Rob

--- On Wed, 11/19/08, Ari Footlik <ari@...> wrote:

From: Ari Footlik <ari@...>
Subject: [Vantage] Backward Scheduling to Include Extra Parts
To: vantage@yahoogroups.com
Date: Wednesday, November 19, 2008, 12:26 PM






I just realized that there is an opportunity to greatly improve our
scheduling of jobs. Specifically, what I realized is that for every job
we always plan to make (and actually make) extra pieces, but we do this
without informing Vantage we're going to do it.

For example, we have an order for 50 pcs and we know we're going to make
56 pieces (just-in-case) , but the order in Vantage tied to the job is
for only those original 50 pcs. Therefore, the backward scheduling is
done only for 50 pcs, and there is no allowance in the schedule for the
extra pieces we *know* we're going to run. Even in the best case, then,
where we hit the target minutes/piece, we'll still blow the schedule
because we took the time to make 6 extra pieces!

So, what is the best way to include these extra pieces in the
scheduling? Do we do add a "Make to Stock" demand for the job (if we
scrap some of the 6, won't we get an "under-quantity" warning)? Or do
we add 6 pcs of scrap to each operation (would we have to add it to
every op, or just the first and it'd carry through)? Is there another
option I'm not seeing?

Thanks!
--Ari