I’m building a book mold for a vertical injection molding machine and the molding house sent me this image for their…injector nozzle? I need to find the matching hardware insert/sprue bushing for the mold.
TIA
Hi again, still very green in this discipline, I'm back asking for more tips.
I took the initial advice I got in this sub and decided to do two identical cavities to keep fill volume balanced. I've done another proof-of-concept with a 3d printed mold and a two-part urethane material, this time with a 70A Shore rating, and removal from the cavity was still very easy despite the slight undercuts, so I'm still confident no ejection will be necessary. There are still some gas traps (see last image), which I kind of expected since there isn't great venting in my 3d printed molds. Before I start cutting metal, I need a sanity check on my vent gate design. I've been reading all the online resources I can find on the topic, and this is where I'm at currently:
Cold runner system. Tool material likely to be 6061 Aluminum. 1.5oz / 2.7in³ total fill volume including runners and sprues. Injector has a 2oz. shot capacity so I think I have a decent buffer for the machine. Melt material is Nylabond 6091-70 PA-6.
The closest equivalent TPV I could find is Santoprene, so I used those venting guidelines as a starting point. Vent lands are .001" deep and about 0.125" wide, the horizontal clearance/vents to atmosphere are about 0.125" wide and 0.02" deep. The vertical (cylindrical) vents to atmosphere are .05" diameter.
Do you see any glaring red flags here? Is it ok to connect a parting line vent land and top-of-cavity vent land+relief to the same hole, as is shown in the second image, or do I need separate vents to atmo?
Will the vents in the 3rd image be functional as designed or do you think they will be prone to clog?
Any other tips?
Thanks in advance.
ETA: A coworker suggested I try to keep all the vents at the parting line to keep them from clogging or to be able to clean them out if they do get flashing in them. In order to vent to atmo at the parting line this would mean some really long clearance channels to get around the runners. Is it worth redesigning the vents I have?
I'm a machinist who dabbles in tooling design and I've been tasked with creating an injection mold to apply over-molding to an inductive proximity sensor cable on two ends. The two halves of the mold are 2x4x8" approximately and will be made from aluminum. There are 3 inserts on each half that will handle unmachinable geometry and a small undercut. I have the cavities designed, and I have a fill nozzle port location from the molding house. I'm assuming I won't need ejectors to remove this from the mold, even there is a small undercut in one section. The material should be pliable enough to remove it without damage. It will be relatively low volume (a couple hundred units a year probably), so it doesn't need to be overly complex. I believe I have chosen good locations for the fill/vent gates, but what I need direction on now is fill/flow path design considerations.
The ratio of the fill volumes between the two ends is about 1:6. How important is balancing these two volumes? Can the disparity be compensated for with the runner volume and vent gate orifices?
How do I select fill and vent gate orifice sizes? I don't want to go so small that the cavities don't fill properly, but I don't want to go so big that I have to start all over if the orifice needs fine-tuning/modification.
Are there any glaring issues you can see with my design so far?
Thanks in advance.