% of Scrap in molding process

[Josue]

Hi:
I woul like to compare, or check our molding process scrap metrix with yours

what % of scrap do you have in your process? what its an "acceptable" target?,, i know this could change from company to company,,ideal should be cero,,, current we have as a target 0.60% for inprocess scrap , we run 7/24hr,, convert that in a $ we are also inside of our target, however our parts are not so expensive and the Failure cost its not so big,, but Im not sure what could happend if our parts where more expensive, may be this ratio could be not aceptable....

[rickbatey]

Hi:
I woul like to compare, or check our molding process scrap metrix with yours

what % of scrap do you have in your process? what its an "acceptable" target?,, i know this could change from company to company,,ideal should be cero,,, current we have as a target 0.60% for inprocess scrap , we run 7/24hr,, convert that in a $ we are also inside of our target, however our parts are not so expensive and the Failure cost its not so big,, but Im not sure what could happend if our parts where more expensive, may be this ratio could be not aceptable....

I tend to use anything less than 3% typical, less than 2% automotive standard, and 1% or less world class! Usually below 3% nets you bonuses and they go up the lower you get. But less than 3% is great when you do mold, resin, and color changes everyday or few hours!! I only use dollar amours when it comes to setting you top five for fine tuning.
Rick.

[brentb]

I completely agree with Rick! Is this a 1st?

KOM

[rickbatey]

Brent- I'm afraid not!? We tend to be on the same page or perhaps at least same chapter in the book. It's just the accent!
Rick.

[brentb]

I again agree with Rick!
KOM

brent

[nemanja]

also big question is how many is human factor involved. with some products we had 6% scrap parts, and with human factor removed, now is below 1% (for some products are 0%).
nemanja

[brentb]

Please define "human factor"
KOM
brent

[Chris]

Please define "human factor"
KOM
brent
brent,
i would think of that as if a person had to operate the molding machine, instead of robotics.

as we all know, most of the time a person will make more errors, then a fined tuned robot such as part take out time, damaging the parts..ect..ect

[Josue]

brent,
i would think of that as if a person had to operate the molding machine, instead of robotics.

as we all know, most of the time a person will make more errors, then a fined tuned robot such as part take out time, damaging the parts..ect..ect

human factor could be a semi aoutomatic operation, like insert molding, however, finally scrap is a scrap no matter the type,,,good that you reduce to much the human factor, what you did? training?, dicipline,? operation manuals?//?

[nemanja]

"human factor" is included when pre-mold is needed also assembly parts in mold tool (my case), and sometimes other preparing operation (dont have connection with actual mold process) can be responsible for machine scrap.
We make training of just one group of woman's for this type of job. from my experience much better is to have one team who "specialize" one operation, than have many who are semi-trained.
Also there are fore each major step working instruction with detail explanation how to use tools and machines. And for discipline, i use "stick and carrot" system, and results in 6 month are weary good.

[_CROW]

Hi:
I woul like to compare, or check our molding process scrap metrix with yours

what % of scrap do you have in your process? what its an "acceptable" target?,, i know this could change from company to company,,ideal should be cero,,, current we have as a target 0.60% for inprocess scrap , we run 7/24hr,, convert that in a $ we are also inside of our target, however our parts are not so expensive and the Failure cost its not so big,, but Im not sure what could happend if our parts where more expensive, may be this ratio could be not aceptable....

How much scrap is discovered outside of your process?

[Josue]

How much scrap is discovered outside of your process?

80% of the scrap its Short shots, we receive china tools, we already learn about it,, the injection gates design was affecting the flow, we open the gate diameters, make alots of vents,, now we are improving,, also a big factor for short shots, was the usage of recycle, the molds with Hot Runner get blocked due to a Spear system dimentios, and another cause, we had alot of down time because we had to separate mold plates, dissasemble spear covers.... now we start to use cold molds (we regrind alot) and install metal separators, and now we are good, but still have alot of chance to improve

about operator inspection, some times a mold get a broken insert and we cant detect until we pass more than 100pcs, this a big problem, one operator handle several mach, so we are reviewing our process to improve this issues..

[nemanja]

As i understand, you have on one tool multiple inserts, for several products? In that case is weary important how you keep unused inserts, are they completely clean and without roast?
"Hygiene" of machine and tools can be one of factors who reduce or incise scrap.
Also one issue with i had problem in past is outside temperature. If temperature around tool to much goes up and down, can make process unstable after some time, specially if you run hot runner with open plate. It happens sometimes on tools from China.

[Pilot]

I am agree that is difficult to compare scrap between moulders.
But ahyhow, I have 16 machines 350-2700 tons avg. age 15 years, 99% of visual parts, avg. 2 toolchanges per machine per day,12 colours, 7/24 production. AVG scraprate is 1,6 %.


But is better to compare material usage efficiency...