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Inventory control and maintenance

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Inventory control and maintenance | 24 February, 2015

We currently have around 20k+ components in stock. I would like to have some opinions on creating a more lean manufacturing system. We check stock in our system and then order parts. Most of time leading to employees looking for parts, or shorts. We are a last in, first out method. Since we have so much components in stock from previous jobs. How do we switch to a first in, first out method. Or to kit better to where we do not have to waste labor looking for parts...and have all needed parts in one kit per job. Thanks.

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Inventory control and maintenance | 24 February, 2015


The best way is to sort your components for each shape type by expiration date and than by delivery date. This will give exactly what you need to reorganize from lifo to fifo.

Best Regards, Alexei

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Inventory control and maintenance | 24 February, 2015

I assume you have a part number system. If so, you should kit the reel with less parts first from the same part number. If you don't use part number system, then you probably have components sorted by value and size, which should lead to the same principle.

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Inventory control and maintenance | 25 February, 2015

We currently do have part system in place. The problem that we are having is finding the same part used on multiple jobs. We it be sufficient to keep most used and common parts on hand. Then turn kitting into fifo.

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Inventory control and maintenance | 25 February, 2015

What software do you use to track your parts? We use Manex - it is not perfect but still gives you the opportunity to track parts/jobs relations. For example I know in each moment one particular part goes to 5 currently open jobs. You should explore your options in software.

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Inventory control and maintenance | 26 February, 2015

We have an older version of DBA and are currently looking into Next GEN DBA. I would like more insight to how other manufactures handle their inventory, whether a FIFO or kitting process. Thanks.

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Inventory control and maintenance | 26 February, 2015

We ran DBA for quite a while but had the same problems you are describing. While DBA has some good features, I just don't think it's robust enough to handle a large CM. Maybe robust isn't the right word as DBA classic has a lot of features. It's just that the features are difficult to utilize for accurate part tracking.

The user interface just plain sucks as well. I wrote a nice windows interface to the underlying progressive database tables so we could chuck the clunky interface and have a nice clean gui that was tailored to our needs as a CM. This helped a LOT, but I found myself adding new tables to track inventory, last quoted price/leadtime, and better part management on open WOs. All these tables were added with a second database using a MySQL server.

After adding so many of these new tables I just bit the bullet and finally abandoned DBA. It's all MySQL based now and it's never been better. The only downside is that I don't have accounting functions in there yet, so we still need to use QuickBooks for invoicing, payments, and payroll. Everything else is in MySQL, SOs,WOs,POs,detailed part tracking of where/what wo every part in the system is at any time, logs of who/when received or issued parts (really handy when you're trying to locate lost parts that are under somebody's workstation),realtime barcoded routers & labor tracking, employee clock in/out, automatic emails of POs to vendors, accurate job costing reports & quoting modules, release document controls, machine setup, ect.

So my suggestion would be to write your own or find an open source MRP that you can modify. It won't be easy, but I think you'll find that it's worth it.

If you continue with DBA, I would offer these suggestions, many of which you may already be doing.

- Manually kit each line item from Inventory to the WO including any excess. Don't issue an entire reel and only tell DBA you took only the WO rqd amount.

- Reel Count back into inventory when the WO is done.

- Maintain your own unique company part number for EVERY part you buy, including different MNFs of 10k,5%,0805s. Have one number for KOA, one for Panasonic, ect. We use a suffix so at least the base number is the same and it's easier/quicker to find a possible substitution if allowed by customer. DBA will let you assign multiple MNFS for one part number, but this causes some trouble when you have two different customers and one allows cross A,B,C and the other only allows A & B. Bite the bullet and assign a unique number to every part and then add the appropriate parts as substitutions on the BOM. You want to keep a one to one mapping of your part number -> unique mnf/mnf part number.

- Be meticulous on maintaining your WO Boms. Train your employees to not circumnavigate keeping the WOBOM accurate to what they kitted/placed on the board. If you keep the one to one part number relationship above this is easier as it won't let them issue the wrong part number to the kit, although they can still just blatantly make a command decision on the floor and ignore the system.

- Be diligent about issuing parts back into inventory as quickly as possible after the WO is completed & do a sanity check on the total inventory count at that time. Doing this basically acts like a cycle count. Don't let the kit excess sit out there for a week after the job has ran.

- KanBan all the common parts, 0.1ufs and such and just keep x number of reels on hand at all times. When you get down to your trigger point, reorder to your target level. For instance we only order decoupling caps in 5 reel packs. When Inventory gets to the last two, another 5 get's ordered and is here in three days.

I don't know if that was helpful or not, but at least it's food for thought.

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