Knowledge & Community You are here

Typically, a minimum draft angle of 0.5 degrees for core and 1 degree for cavity would work for ABS, but this can vary based on other design factors. The deeper or taller the part, the more draft is necessary. For every 25mm of depth, increasing the draft angle by 1 degree is a common rule of thumb to follow. The required surface finish of the moulded part also influences the draft angle. A rougher finish may require a greater draft angle to release cleanly from the mould.

[marc howard]

Hey everyone, I’m currently working on a project involving injection moulding of packaging items with ABS plastics and could use some advice. I’m trying to figure out the best practices for designing moulds with draft angles. How do you decide on the optimal draft angles? Any tips here would be really helpful. Thanks!

0

[gregory.demarque]

Hi Marc, 

Part design may require different type of draft angles depending on : 

– Height of the wall to demold, 
– Texture applied on the wall, 
– Material to be used, 
and of course…what is acceptable on the final product. 

0.5° (per face) is minimum for height < 25 mm
1° (per face) is minimum for height <40 – 50 mm
1.5° may be needed for higher design.

regards ! 

 

0

[marc howard]

Hi Gregory, good points, thanks for your reply!

0

[Damien P. Brown]

Typically, a minimum draft angle of 0.5 degrees for core and 1 degree for cavity would work for ABS, but this can vary based on other design factors. The deeper or taller the part, the more draft is necessary. For every 25mm of depth, increasing the draft angle by 1 degree is a common rule of thumb to follow. The required surface finish of the moulded part also influences the draft angle. A rougher finish may require a greater draft angle to release cleanly from the mould.

0

[marc howard]

Thank you, Damien, noted this

0

[Anton Huryn]

I would like to add that every material has a shrinkage index, which must also be taken into account.

The shrinkage angles must be adjusted to this value as well.

We have a lot of experience in making export molds and believe me I know what I’m talking about 😉

0