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● R&D

typical cosmetic defects of Black PEEK

by Eureka_Admin 2024. 5. 3.

 
Recently, I started making pens with Black PEEK.
I purchased the rods from a South Korean manufacturer.
they used German PEEK pellets to produce the rods.
 
Despite my nearly perfect pen making process,
when I started machining the material, I noticed several types of common cosmetic defects.
 
1. white dots (common)
2. tiny metalic dots (rare)
3. small cavities (common)
 
the white dots are the most commonly occuring defect, followed by cavities, then seldom metallic dots
I contacted the rod manufacturer about this.
They said, "although they are trying their best, and still working on perfecting the quality,
it was very difficult for them to avoid 100% defect."
 
for this reason, I concluded, the defects were unavoidable for Black PEEK material.
If I wanted, I could use German black peek, the quality should be better,
but the end price for consumers will more than double...
 
so, from now on, I will rank the overall quality by examining severity / number of the small defects.
S (Nearly Perfect) = There will be a very few S grades, almost none.
A+ (very good) = a few small defects
A (good) = a bit more small defects (compared to A+)
B (acceptable) = more small & a bit larger defects / or a few large defects (compared to A)
 
* for the grip sections, nearly all of them are S grade.
* only the Barrel and Cap are affected.
* other parts such as nib & ebonite feed are all the same.
 
i will determine the price according to the rank, with S rank being the most expensive.
these defects are merely cosmetic, functionally there's no difference.
the best bang for the buck is the B grade, if you don't care about some minor cosmetic defects.
 
 
the pictures below shows magnified images of small defects.
when you actually see them, the small defects are much smaller.
for the larger defects though, they will be more noticeable than the small defects.
the defects are no big deal, if you intend to use the pen as daily driver.
also, if you aren't so sensitive about perfect external appearance, they shoudn't bother you.

 

 
 
examples of very large defect (this is approximately the maximum size of the defect)
defect length = about 1.5mm
(for some extreme cases, i've seen white dot size upto 3mm. It is likely to be classified as "C grade")

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