hello, I need help, I have a new tool ( Blower wheel fan ) , but the gate design is not to good , and it is causing a lot of troubles to balance the parts after molding. Due the gate design , the plastics is not moving in to the tool uniformly , and this is causing bad balancing , I trying to find someone that could have experience on this kind of products and share some file and pictures to determinate if have to change my gate design or do something different .

Thanks

Gate size, cavity pressure if multicavity, air venting, cold slug well, these are few factors affects balanc filling

Saravan

Guillermo, send me an email and we can share information. We do a number of fans now up to 10 pounds weight and use two gating strategies successfully. To give you some ideas I will need to see what you have for gating and part size and what you have as imbalance.

maybe you can use the Moldflow software to simulate, then you can find some problems for your guidance

Dear Guillermo, I agree with the idea to launch a mold flow simulation. If you wand I can have a look to you product and gate and offer you a fair price to simulate a solution.

I had the same problem with a mold (blower) and apply the Moldflow, the result was a hot new hotranner developed by Moldmaster.

I would not think to make a recommendation considering the extreme lack of data, however presuming that this has a diaphragm gate in the centre where the drive shaft fits, my first thought would be the core is possibly deflecting and allowing more thickness and more pack on one side. Once a core starts to shift the situation quickly escalates as even more material runs down the thick side and pushes the core across even harder.

IF this is the case, while the uneven flow appears to be a gate problem, fixing the core location will solve the problem irrespective of gate.

Of course if the gate is not into the fan axis area or it is a flat fan where core shift is not an issue this post is useless.

Also if it is a flat type fan, you might have eneven cooling also causing more restriction to one side. Your support pillars might also be inadequate.

It really epends so much on what6 has not been disclosed.

what kind material you use, mold temp.is very important, i do have some experince in molding fan ,but i use pps with carbon.

you have to confirm the problems was caused by mould or by plastic injection machine setings. so first try the mould with good injection parameters suggested by the raw material specifications, depends on the raw material brand and grade, if it was big grade as GE plastic you can find the datasheet on the web directly, or you can ask your supplier, and set the material melt temperature same as the raw material datasheet provided and also for the mould temperature. then see the result. and use tools to measure the real material temperature when it's shot out, some times the problem was the injection machine itself. and injection speed, you can try fast inject and slow inject to see the different, if it was the air vent problem, add some air vent, when all was good still not have got result, you can check the mould.