Mash Tun size... I did read the sticky

I am just getting into all grain and need a mash tun. I normally make beers under 1.080 og, but could make an imperial at some point. I plan on doing only 5 gallon batches, so I am looking at a 10 gallon igloo but my concern is if I want a brown with an og around 1.044 that cooler will have too much head room. I don't want the 5 gallon size as I think I will find myself doing beers too big for it.... so I've searched around the forums and found no real answer.... any advice? Thanks

I make lower gravity brews all the time I'm my 10 gallon gatorade cooler. And it may drop a degree over an hour. I would say go with the 10. Then you can also brew higher gravity brews.

I use a 48 quart igloo cube with grain bills from 8 lbs to 24 lbs. I lose about 2° an hour with the smaller grain bills.
I did insulate the lid with spray foam.

Too much worrying for no reason.

Yeah I'd go with the 10gallon. Worst case if your overly concerned with the headspace you could always get styrofoam blocks and cut them to fit just inside the mash tun. But I think that would be more hassle than it would be worth. 1-2 degree loss over an hour is not going to be detrimental to your brew.

To get a good idea of what size mash tun to get visit.

http://www.rackers.org/calcs.shtml

The 3rd calculator is what size mash tun. You can enter all kind of different scenarios. Plug some of your recipes in, decide what size fit's best to your brewing. If you are thinking 1.080 beers I'd go 10 gallon.

You can pull maybe 1.060, to 1.070 if your efficiency kicks ass, out of a 5 gallon mash-tun. Most I've gotten out of mashing in 5 gallons was 1.066 where I hit diminishing returns. So you can brew a lot of beers with 5 gallons, but you'd definitely be better suited with 10 gallons (unless you want to make higher gravity batches in smaller batch sizes).

I have one of each. I usually do double batches. Honestly, I like the 5-gallon better. It holds heat better. I use it whenever I can, but it's definitely too small for bigger beers.

didn't expect this many answers so quick... thanks for helping make up my mind! Now gotta decide... false bottom or screen... leaning towards false bottom

Braided tube to start with. Cheap.

Build a manifold