No clue, can't imagine the colour makes a difference.... You can get Delrin with or without glass-fibre filling as well, totally changes the strength.... Sometimes that might be important, others not.... It would depend on the load (valve throat area times pressure).... MRod poppets are black, and they work great....Bob
My locL selling supplier said there is no difference. Some like the white for use in food service applications so they know the item is thoroughly clean before reassembly.
..MRod poppets are black, and they work great....
Im a Brit materials engineer ...teaching the subject ...White Delrin is often chosen over Black, especially in Pneumatic systems because its very easy to see emoilents or other contaminates...I actually prefer Black in springer guns as you cannot see it so easily through cocking slots and i just prefer black parts but many choose white as its easy to check if the component is greased...in opposite to the bove reason where cleanliness is absolute
Most people use "Delrin" to describe the engineering thermoplastic commonly known as acetal. Not all acetal is the same.Color will not make a difference in strength or machinability. The type of Acetal you have will make a bigger difference if you are machining parts from extruded rod or sheets.I prefer Copolymer Acetal round rod for making parts on the lathe. Dupont's Delrin® is an acetal homopolymer, when extruded (I.E.Round Stock) it can have center-line porosity issues that may cause problems when machined in terms of strength, consistency of machining and moisture permeation. When injection molded, it is typically stronger than Copolymer Acetal. On my CNC lathe, I use very sharp polished carbide inserts as used for aluminum at High feed rates and high SFM for roughing and low feed rates and high SFM for finishing. High feed rates cause the plastic to chip, low feed rates create strings that like to wrap around the work piece (!@#$^%). With parts larger than 3/4" diameter, going for a greater depth of cut helps prevent the strings from wrapping around (they come off like coil springs when you are in the sweet spot. I have had success machining it dry or with coolant.With HSS tooling I'd try for a high clearance angle and as sharp an edge as you can get. I don't think you will need coolant.-CindiP.S. I do have some short Copolymer Acetal round rod ends in the scrap box if you need a few.