Knowledge & Community For Engineers & Product Designers

Looking for advice on reducing warping in injection molded HDPE parts, especially for components measuring 800×600 mm, where we see significant warping at the corners. Despite adjusting mold temperatures between 220-240°C  and experimenting with cooling rates, the improvements have been minimal. Maybe anyone has ideas how to optimized holding pressures or specific cooling times? Also, are there particular mold design modifications or additives known to help maintain dimensional stability during cooling cycles lasting 30-45 sec? Thanks in advance!

Hi, I’m in search of a 3D printing material for serial production that can withstand temperatures up to 85°C. Could you please recommend the most cost-effective options among those that you offer that meet these specifications? thank you

Hi all, I’m currently working on a marine application focusing on submersible components that require 6061-T6 aluminium. The part must undergo anodizing to ensure its wear and corrosion resistance when exposed to seawater.At the moment I’m considering type III hard anodizing. However, I have some concerns regarding the possibility of fatigue cracks in the anodized layer due to the part experiencing tensile stresses up to 40,000 psi and compressive stresses up to 35,000 psi and high cycle fatigue (with stress cycles expected to exceed 10^5 cycles). I’m afraid that further cracks could not only lead to corrosion but also cause the part to crack.Considering the need for both corrosion resistance and wear resistance, I’m determining the most suitable type and thickness for the anodized layer. Initial recommendations suggest a thickness of 25-50 μm for type III anodizing to provide a good balance between wear resistance and the ability to withstand mechanical stresses without significant risk of cracking.However, I’m interested in hearing if there are alternative recommendations or insights based on practical experiences or additional research. Thank you!

Hello!I’m planning to use CNC machining for plastic parts (Delrin/POM) for the first time and have typically worked with metals before. I’m considering the ‘as machined’ finish with a standard 3.2 µm surface roughness.For those who have experience with plastic CNC machining, can ‘as machined’ parts generally be used as end parts, or do they often carry too many machining marks? Would it be better to choose a bead-blasted finish (or another type) to enhance the appearance? These early prototypes might be shown to our end customers, so they need to look reasonably good. Any tips or experiences would be very helpful.Also, could anyone share some pictures of polymer parts you have produced using CNC machining? I’d appreciate it!Thanks, Marcin

Hello,I am a mechanical engineer currently in the design phase of developing rectangular housings using PA66 GF30 material. From my previous projects, I’ve encountered challenges with achieving consistent dimensions, particularly with thin wall sections. In my current design, a critical feature has a specified wall thickness of 0.7mm, which I suspect might lead to warping and strength issues based on past experience.To preemptively address potential problems, I am considering adjusting the wall thickness. However, this could affect the overall width, initially designed at 80.0mm (+/-0.05mm).What is the generally recommended minimum wall thickness for injection molding of PA66 GF30 to ensure structural integrity without compromising dimensional accuracy?Given the stringent tolerances required, would it be appropriate to adhere to ISO 20457 for general tolerances in this situation, which is specifically tailored for injection molded plastic parts?I would appreciate any insights or suggestions on how to best approach this design challenge.