Hi,
Have you consideres to change the gate location? Probably just by offsetting the gate you will manage to move the weld line to a less critical area.
I agree with the comments before, if the issue is not constant then probably has something to do with processing or resin variations.
GP
Thanks Chris,
In fact I was a bit under stress because I could not find any data on-line nor in my books collection, but in the mean time I found some info.
COC is the same as COP but co-polymerized with blocks of ethylene (as suspected). I also find some differences on transmittance and...
hi, can someone explain me the difference between COP and COP from structure point of view and let em know if there is any difference on their processing compared to each other?
Thanks
Gil
Hi all,
Is there anyone aware of a free mold filling software?
I would like to have only a rough estimation for pressure drops and filling time. Shear rate profile, crystalization, warpage, welding lines... etc are not of my interest with this free software.
Thanks...
Hello all,
I'm working on a layout concept for a stack mold with one cavity on each side (2x1cav).
From the mechanical stability of the mold on the machine and the mold itself, what solution would you prefer (pleases see attached picture)?
My opinion:
Solution A
advantaged: Forces will be...
Hi,
At university I had a course where I learned to compute the pressure raise and pressure drop (on the dies) on one extruder along the screw. We were using transport equations to compute the flow in the screw. The equations were divided in three steps, one equation for solids transport, other...
Hi all,
I'm looking for literature that could help me to define limits on the shear that you can apply to a certain polymer family.
In the books that I have (for example: Runner and Gating Design Handbook: Tools for Successful Injection Molding and Mold Engineering) I have a table and some...
Hi there,
Is difficult to understand this post. As far as I understand from here I agree with Demon.
Which kind of material are you looking for? Independently of the type of the material (polymers, metals, ceramics), their behaviour can be defined according to 3 big groups: (1) pure elastic...
Hi all,
Today during a chat w/ some friends at work we end up at the question, which is the difference between HIPS or Styrene Butadiene Copolymer? I would like to share this question with you people to know also what you think about it.
As far as I know HIPS is made out PS blended or...
Hello,
Should they remain intact after the shoot? Maybe ABS or PC/ABS but I guess that those are too much for the application. I would say that a HDPE would work just fine. It should be stiff enough to be pushed into the ground and shound have enough impact resistance.
I remember that when I...
Hello all,
After my studies in Polymer Science and Engineering I decided to study by my own Polymer Rheology as I think that it's a powerful tool to understand a couple of flow behaviors in processing.
I would like to share with you what I found. For those who are interested, you can download...
Hi,
I'm not experient enough but maybe there is other material that you can take into considereration:
Vespel(R) from DuPont (it's a polyimide). Specialy filled with graphite, offers good mechanical and wear properties is a large range of temperatures.
Does anyone else has experience with this...
Hello
I know that some guys in UK made an "acoustic" violin with carbon fibres and epoxy resin. If I remember they used an autoclave system to manufacture the different components.
Maybe you should look for something like that.
I try to find the web page but I can't find the same web page that...
Hello ppl!
I'm not sure if I wrote this here some hours before, but as I can't find it... I'll write it again.
I need to increase the static electricity in glass fibres. Anyone has an idea about how can I do it?
Sorry but I can't give more information.
Thanks for you replies in advance.
The problem is that I need to analyse those samples in SEM and I want to get the structure intact. The thermoplastic has a melt temperature around 150 ºC so this is not the problem! I just want to make sure that the composite's structure or the polyemer's microscopy do not change.
Anyway...
Thanks "mechanicalchef",
I'll try something similar but I'm afraid that this blade can "kill" my specimens... I tried a usual blade to cut metals...
If someone has more ideas, they will be welcome!
thanks,
Hello,
I have long fibre reinforced composites samples with 10 x 50 x 2 (mm).
Composites have a thermoplastic matrix and glass fibres.
I'm trying to cut those composites in smaller samples of 5 x 5 x 2 without change their morphology.
I tried to cut those with a saw but the result was not so...