What is this in my finish? (Pictures)

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Tetsuaiga

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I'm using epoxy as a finish and have these bits after the finish has set.



Sanding it out till they're gone but I'd just like to know what they are, dust?

Why does it create a kind of island around, do the specs perhaps gather extra finish to them because of some sort of surface tension?

Thanks
 

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I’ve seen similar when silicone is in or under the finish. You use any lubricants or waxes that contain it on your tools?

Pete
 
Hi no I dont, the wood was drum sanded then hand sanded after.

However this is my second coat and epoxy does create a thing called amine blush which is like a greasy wax you remove with water and sanding itself. Perhaps I didn't get rid of it properly, if it's not caused by dust nibs.
 
As a non-expert, and based purely on web images, it looks like it may well be amine blush. Apparently it is caused by moisture and CO2 - can be exacerbated by gas heaters used to speed up drying times (boat building etc).

This site says to use warm soapy water, and not sand it. https://epoxycraft.com/top-tips-best-wa ... ine-blush/

(I am about to do my first ever major epoxy fibreglassing, so I am big on research, but have zero practical knowledge)
 
I once had something simular when finishing some Iroko windows.....it was silica coming out of the wood.....after time it disappeared.

Jonathan

Sent from my SM-J530F using Tapatalk
 
+1 for amine. I get it a lot when glass coating etc as my workshop is about 80m from the north sea and with the heating on can tend to be a little high in relative humidity. keeping the room warm using electric heating and having closed doors prior to mixing and pouring seems to help a bit. Although if you are using an oily wood make sure you give it a very good going over with acetone before hand helps too
hth
 
Thanks everyone, i think better cleaning is the thing to try next. I am applying with roller and tip off with foam brush.

The wood is cherry so cany imagine that is the source of any issues.

I'll try and post back once the next coat is done.
 
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