Course Grain Bags

The kits from NB come with a course grain bag. I use these for steeping the grains and my wort usually ends up with a fair amount of small grain pieces that come through the bag. The grain also has a fair amount of 'dust' from the milling and this also ends up in the wort.

I have a few questions about this:

1) Is it normal to have a moderate amount of 'dust' in your milled grain?
2) Does anyone shake this dust out before putting the grain bag into the kettle?
3) Does boiling this dust and small grain pieces extract tannins? It must, right? but could you notice it?
4) I plan to do some partial mashes with a 24"x24" fine mesh bag. Should I just use this mesh bag instead of the course grain bag that came with the extract w/grain kits?

Great questions. I'm moving into steeping and mashing grains and would love to be informed on these matters as well. Consider me subscribed.

1) yes
2) i don't. don't think ya need to
3) never noticed an issue when i was brewing extract with steeping grains
4) i use pain strainer bags, they're cheap and nothing but liquid gets through.

The flour from the grind is very normal- just a part of the process. You don't want a TON, but you should expect some. Leave it in- it will help your efficiency. I don't think you'll get any noticeable tannins from the small amount of grain that escapes the bag- I had a paint strainer bag rip on me (my fault) and got a few grains in and boiled them to no ill effect.

I highly recommend the home depot 5gal paint strainer bags- tight enough that no grains will get through (unless you rip it, like I did) and loose enough that you get plenty of wort circulation. The bag you use for your PM won't matter- use whichever you prefer.