I have watched a whole bunch of youtube videos but I am really struggling to create a mold for this guy... Can anyone give me some tips? 
Also - SW file attached.
I know what this needs to look like but I am hoping the mold tools would speed it up...
Thank you!
John,
Few clarifications,
I don't think the mold tools alone can do the split, need to use other surface tools to complete the task
John,
Thank you for helping out.
It will be but the mold I am creating will not go into production - this is a proof of concept - we have a separate company that designs our molds. I want to be sure this is moldable. So ignore draft.
Material is HDPE.
When you say surface tools are needed. What is the approach here - Am I creating manually the splitting surface, cutting the part in half and converting it to surfaces, and welding the top of the part surfaces to the splitting surface and creating body? In this case I am not sure what the mold tools would do for me???
First you need to add drafts on both sides of the parting line as John George mentioned - see below image
and you need slides (both sides) for that section
This could be split into core and cavity without any slide or any other action, but the transition between the two is straight and in-line
If this is for a split practice, it will work.
You can use the mold tools, but it won't do the split that easy.
Split the surfaces of the part (use split line command)
Use the parting line, shut-off surfaces and parting surface
Since the hooks and the end shapes are jogged, need to use the surface tools to complete the core/cavity surfaces
Here is how it looks like
The others are correct.
Although someone else is doing the mold design, and you want to check it, you need to design in the drafts to check it.
Split lines can sometimes be tricky.
John G.
You're absolutely RIGHT
Just viewed the part again and there is no need slide for this part
"I want to be sure this is moldable. So ignore draft."
If it doesn't have draft...it isn't moldable. Parting line jumps/jogs must have at least 3 degrees draft (5 degrees is better) off of vertical, otherwise you have a parting line that will "self-lock"...gauld...and eventually flash.
Pull it with a slide from the left end.
John,
This looks great - exactly how I imagined it.... I imagine this took 20-30 minutes? Wish you had this in SW2010 step by step or a recording... I think it would be super helpful to everyone...
All the tutorials on YouTube are for super simple or super-complex parts... And they all lack direction - I know how to follow step by step but they don't tell you the big picture and the smaller pictures along the way - as to why they are doing it a certain way... Thank you!
You are right - easy to add drafts in but i would rather leave that to the mold designer as they would be the ones to know best...
But for the purpose of checking weather this needs to be a 2 or 3 part mold and if it is even possible I think adding drafts unnecessarily complicates things... I like to keep things simple and complicate only if absolutely necessary
John,
For standard practice, I'd strongly recommend, you (the designer) should be the one who adds drafts to the part you design, not the tool maker. The tool maker will design tool based on the drafts you have on the part. If you leave this job to them, they will favor big draft angle for easy to remove part from the tooling and it might affect some of your part's functions
I used SW2015 and I don't have 2010
If you look at the core/cavity inserts and the parting line very closely, might help you to identify the added surface work done.
You are 100% right - no argument there. But we are still tinkering (a wee tiny bit) with the geometry of the part - it might change its shape. I leave drafts for the end. They are usualy 1 or 2 degrees and adding them in at the end does not affect me structurally!
From the standpoint of a Moldbuilder/Mold Designer...by not adding in the drafts you are complicating things instead of making them simple. We do not know the end use of the part. We are generally not supplied with the full assembly that the part goes into. We do not have intimate knowledge of what is critical and what doesn't matter with regards to the function or cosmetics of the part. We will waste your time asking you all these questions so we can figure out how to change the part so that it is moldable and then make the changes to the part before we even begin to split the part into core and cavity...and we will charge you for that time...at an hourly rate greater than what it would have cost if you had done the work yourself. Or even worse, you send it to a mold shop that doesn't ask anything but instead just modifies the part at their own whim as to what will make the tooling easy and the parts that come off the tool don't work because the mold shop took the liberty of changing the part without consulting you and the changes to the parts shape is now causing the part to not function correctly.
I agree 100% with Doug,
Part designer should decide the functionality of the part and how it should work in assembly.
If there is issue with the part when a mold designer start design, he has to communicate back and forth with the product designer and waste lot of time.
Good point, Doug
We always perform full draft and under cut analysis before sending out parts to the vendors but most of the times, we still have at least 2 or 3 discussion with them before "green light" the vendors to cut the steel
I hate to disagree but I think you guys are putting the wagon before the horse... I never said that I don't need drafts - nor am I implying or saying they are un-necessary. They are absolutely critical. But for me right now they are not. The part's shape is changing - right now is not the time to add in drafts - its when the part shape is complete (not part design - part shape)... Would you not agree? What makes the part even more flexible is that only the teeth are of real importance for drafts - they interact with another part - the rest of this body is molded in foam - meaning I don't care if the part deviates 1 degree left or right its burried in foam and its primary goal is not interaction but adding strength to foam.
But understand this gentlemen - I am not being combative - I AM CRAZY THANKFUL TO EVERY ONE OF YOU FOR YOUR HELP ON THIS!!!! LOVE YOU ALL!
"You are right - easy to add drafts in but i would rather leave that to the mold designer as they would be the ones to know best..."
We all tried to help and ... sorry you felt that way.
I'm just concerned because you said "leave that to the mold designer" in you mesg
yeah - my current practice is to add in drafts for teeth only and let the mold designer add the rest for the part which i don't care for. Maybe it needs improvement.
If you want to run a full check, you need the drafts.
If you rely 100% on your vendor, and you don't get the chance to check the part before the mold is made, you have the chance of an expensive error.
Sometimes the part shape must change in order to get the draft required for the parting line. Your part is a textbook example of it.
There is draft that is simply required so the part ejects nicely or so the part does not stick to the wrong side of the tool with the mold opens. Let's just call this draft "Draft for Molding" or "Draft for Release". As a general rule, this is draft that is put on the part towards the end of the part design process.
Then, there is draft that is required for the parting line jogs...the shut-off surfaces of the mold. Let's call this draft "Draft for Manufacturing" or "Parting Line Draft". These need to be at least 3 degrees, 5 degrees is greatly preferred. That is enough of an angle that it changes the shape of the part of your part.
Doug, this is something new... I am still struggling with the parting line terms and shut off surfaces... Is there a plain english for these? Parting line vs parting line jogs?
3 and 5 degrees is quite a bit... But really good info - hope I can understand it for future needs ... This part however - not so much - like I said the red lines in your drawing - they can be 10 degrees - it does not change things much for me...
Parting Line: All the surfaces of the mold that shut-off
Parting Line Jogs: Changes in the Z level of the Parting Line
(Red surfaces are surfaces of the mold that form the plastic part. Blue surfaces are "Parting Line" surfaces. They shut-off, steel to steel. Green surfaces are surfaces that do not form part and do not shut-off. The hightlighted surface is a parting line jog.)
Self-Locking Angles/Tapers: Angles of less than 3 degrees per side. Some use the "rule of thumb" of 7 degrees included angle, or 3.5 degrees per side. If you grind a tapered pin with 2 degrees per side draft on the diameter, and put it into a mating hole that has the same draft, it will "lock" into the hole. It will take significantly greater force to remove the pin, than was used to install it. This condition is extremely undesirable/destructive on a mold. Conversely, there are Self-Releasing Angles/Tapers...which are simply angles greater than what would be a Self-Locking Angle/Taper. Grind a tapered pin with a 5 degree per side draft on the diameter and put it into a mating hole that has the same draft, and the pin will fall out of the hole if you turn it upside down and let it fall out...beat on it with a hammer and turn it upside down and it will still fall out freely. Self-Locking Angles are very bad in a mold, Self-Releasing Angles are very good.
You can use the mold tools, but it won't do the split that easy.
Split the surfaces of the part (use split line command)
Use the parting line, shut-off surfaces and parting surface
Since the hooks and the end shapes are jogged, need to use the surface tools to complete the core/cavity surfaces
Here is how it looks like