Dyneema fluff

[cxz]

Just made some Dyneema soft shackles with some new 4mm single braid Dyneema but was surprised to see that it already has alot of fluff and thread coming off when rubbed against itself. Is that normal? Or what causes this?

[Benz]

It depends on the coating. Natually, Dyneema fibers are very fine and fluffy, and must be coated (preferably in the yarn before braiding) so they keep together better. Different manufacturers use different coatings, or thicker or thinner depending on intended use.
If it's well coated, and it's fraying, then you have a big chafe issue to address.

[cxz]

That's interesting, the soft shackle has never been in use. This was freshly made and I simply rubbed it against itself a few times. The other one I made was in grey and I assume they're not colour-coded.

[StuM]

Note that Dyneema is a brand name (although it has recently become genericised like aspirin, band-aid,biro etc)

Where did you get the rope?
Did it have a brand name, did it come from a reputable supplier or is it just some cheap generic UHMWPE (from China?)

[cxz]

Got it from my local chandlery here in Denmark. Probably did have a brand name, but just saw it come off the spool. Could have been LIROS, but they are a huge EU supplier so I can't imagine there being any production issues.

[fxykty]

Originally Posted by cxz

Just made some Dyneema soft shackles with some new 4mm single braid Dyneema but was surprised to see that it already has alot of fluff and thread coming off when rubbed against itself. Is that normal? Or what causes this?

Not normal at all, properly manufactured UHMWPE line should be quite stiff and smooth even after working due to its individual fibre coatings for UV protection and chafe resistance. Dyneema and ISM are the two original manufacturers and license to others (such as Hampidjan). Acera (Timm Ropes) is a big one in Northern Europe (comes in yellow) that is properly formulated. Cheap UHMWPE line (aka Chineema, but of course is made elsewhere too) may be externally coated only, so the individual fibres will fluff and fray as they are exposed due to splicing. OK for non critical work, but nothing where you expect consistent strengths.