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donbtlr
19th May 2013, 01:06 PM
Can someone explain:
1. Why die height is important.
2. What can happen if the Die Height isn't set correctly.
3. What would the result be if the Die Height was calibrated for a smaller mold, and not recalibrated after a mold change to a larger mold and ***vice versa***.

What I want to find out is if a molding machine was running a mold that was, for example, 4ft wide, and the Die Height was set. Later a mold change was done, and a new mold that is 8ft wide is installed without the Die Height being adjusted. What damage if any could be done to the molding machine? What would the outcome be if this scenario was reversed?

moldingppm
20th May 2013, 04:22 AM
Can someone explain:
1. Why die height is important.
-why isn't it?

2. What can happen if the Die Height isn't set correctly.
-flashed parts, slamming molds, depending on the machine lots of alarms along with problems

3. What would the result be if the Die Height was calibrated for a smaller mold, and not recalibrated after a mold change to a larger mold and ***vice versa***.
-see above

What I want to find out is if a molding machine was running a mold that was, for example, 4ft wide, and the Die Height was set. Later a mold change was done, and a new mold that is 8ft wide is installed without the Die Height being adjusted. What damage if any could be done to the molding machine? What would the outcome be if this scenario was reversed?

See above.
I can tell you're new to this. I'm kind of flabbergasted that this question was even asked, but we all gotta start somewhere. Die height must be set 99.9 +.1 percent of the time. You have to set it. The mold won't lock up, and you'll have all kinds of issues. This is the first thing to do when setting up a mold.

Depending on what kind of machine, setting the height can be a pain. Straight ram presses are the easiest to set, due to it just recalibrating zero.
On toggle presses, it's a bit tougher. Finding the lockup point (I have an older Van Dorn that is this way) is a PITA. Just gotta get a feel for It.

donbtlr
20th May 2013, 06:13 AM
See above.
I can tell you're new to this. I'm kind of flabbergasted that this question was even asked, but we all gotta start somewhere. Die height must be set 99.9 +.1 percent of the time. You have to set it. The mold won't lock up, and you'll have all kinds of issues. This is the first thing to do when setting up a mold.

Depending on what kind of machine, setting the height can be a pain. Straight ram presses are the easiest to set, due to it just recalibrating zero.
On toggle presses, it's a bit tougher. Finding the lockup point (I have an older Van Dorn that is this way) is a PITA. Just gotta get a feel for It.

Thanks for the reply, and yes, I know it has to be done. I want to know what damage if any can be done to the press if it's not done.

I am a bit knew. I know what needs to be done, but do not have a full understanding of the inner workings. We are using Fanuc electronic presses, so it's as simple as a press of a button for us which is one of the reasons for my lack of knowledge.

Pilot
20th May 2013, 06:05 PM
Hi,
Is a clear, that tool hight is important for corrent tool function.
As has been wrote, one issue is not good clamping force.
After toolchanges a lot of machines are required to do die hight setting. Without this procedure you cannot run the tool.
Is existing a one danger situation.
In case, that you will run the tool with hight 50 cm, your zero for tool opening / closing linear is physically in position of moving plate in 50 cm from fix plate.
Now you will instal higher tool (for ex. 80 cm) without of settings of new tool high... and you will close the tool. It means, that your tool is closed and tool position will be indicate 30 cm. In case, that you have a core, which is programmed on moving in 30 cm (normally when the tool is open), machine will move this core (but the tool is closed) and the crash is here...
Analog situation is with robot.... etc..

pjhall
21st May 2013, 11:59 PM
Set the mold up and set the mold height. Plumb the cooling (water, oil, or cartage). If you are running a hot runner turn the manifold(s) / sprue on as well (This adds quite a bit of heat the stationary side) Leave the mold open about an 25mm and allow the mold temp to reach equilibrium then reset the clamp tonnage. If you are running a small part in a big press set the tonnage below maximum. I've seen a cavity crack because the mold was locked up under full tonnage before the mold was heated to 300F. I will often reset the clamp after the tool has been cycling for a few.

If you don't set the mold height you will either (1) not be able to clamp (2) transfer to full tonnage to early and possible damaging the mold or (3) you will flash.