DIY down vest query

I have a down vest maybe 1 inch of loft.  I wear it with a synthetic vest.  That is good for me down to 20 F.  The down vest by itself might be 32 F.  With base layer and jacket.

30 inches long x 50 inches around = 1500 cubic inches.  Maybe a large size.

850 FP down would require 1500/850 = 1.76 ounces.  add 20% overfill = 2.1 ounces = 60 grams, plus a little more for the collar.

You could do a little more than 1 inch loft or make it a little longer, bigger around.

But maybe a reasonable winter warmth would be 2 inch loft.

Jerry I really like the way you explained that.

Using 90 grams makes it equal to something from Uniqlo and I will need warmer than that, OK

I’ll buy another small bag of down then. I did think I had some good salvaged down here but I can’t find it

Or I’ll change the vest to synthetic so I have a LW active layer

My idea is that a synthetic vest (or jacket) is a good survival item.  If you get wet for some reason, the synthetic will still keep you warm.

I was hiking somewhere.  It was raining.  I was a little wet inside WPB jacket.  I got to camp and started getting chilly.  I couldn’t really put on my down vest because it would get wet and lose loft.  After a while I dried off enough and put on down vest.  If it had been colder it could have been more of a problem.

So, I have a 2.5 oz/yd2 Apex vest that weighs 5 ounces.  And a down vest that weighs 6 ounces.  The synthetic vest is good if I’m just a little cold and wet.  Then add the down vest if it gets really cold.

@Moondog55 , this might be of interest to you. Dutch just put them on sale but didn’t say for how long.

Thanx Hoosier but O/S postage makes that a non starter as my local supplier has it for not much more in local pesos