Brewing Liquor Leaves Me Short

[ADDLED]

Im recently having issues with not enough wort in the FV and I cant fathom where im going wrong.
I did this brew yesterday and heres my sparge calc;

Enter Volume Required In Fermenter ie Brew Length e.g. 23L: 40L
Percentage Loss During Boil e.g. 15%: 15%
Enter estimated loss to hops and trub eg.3L: 5L
Total Grain Bill e.g. 4 kg: 8.6kg
Enter Dead Space in Mash Tun: 1L
Enter Water/Grain Ratio for the Mash in Liters, eg for a 2.5 : 1 ratio, enter 2.5: 2.0L/kg

Wort Required for the Boil: 52.9L
Made up from two equal quantities of: 26.5 liters of wort collected from the mash.
Total Quantity of Water Required For Batch #1: 36.1L
Mash Volume: 17.2L
Top Up With: 18.9L
Water Required for Batch #2: 26.5L

This brew should be 1.049 OG. I make it that the total liquor i need to start with is 36.1l for batch 1 and 26.5l for batch 2, so i start with a total of 62.6litres in my HLT. So i heated up 65 litres and carried on. I didnt have the room in the mash tun to batch sparge so i used a watering can rose to fly sparge. By then time i had boiled i ended up with around 30litres in the FV so i had to top up with water.
Wierder still, I topped up to 40litres but the OG was waaay high, 1.062.
I dunno whats happening; im getting vastly lower wort yields that are massively over gravity.
I thought it might be because i was at the end of a 25k sack of malt ang getting a lot of flour, but I used a new bag yesterday. Mebbe its the hops? I dont know how to calc the volume of liquor the hops suck up, but by the weight of the empty boiler its a lot.

Any ideas?

[adm]

FWIW, when I moved to my shiny brewery, I kept coming up a few litres short at first (again with higher gravities), so I've been tweaking it over the last dozen brews or so.

The main culprits were that the propane burner was causing a much higher evaporation rate (now I'm careful to keep it to minimum power to sustain the rolling boil), plus my efficiencies have been getting steadily higher and higher.

On the subject of the hop absorbtion, I've also been keeping track of that recently and it appears that whole flower hops will absorb about 14-15ml of wort per gramme of hops. Call it 1.5l per 100g of hops. Add this amount to your standard boiler deadspace

Also - as Chris says, the wort has more volume when cold than hot - by about 4%.

That's not going to account for the big differences you mention, but it will go some way to helping. I've got a little spreadsheet I've been using to calculate the water volumes with that takes both of the above into account. PM me if you want a copy.

[adm]

Also - as Chris says, the wort has more volume when cold than hot - by about 4%.

otherway round

Oops! It's the old "heat things up and they expand" trick!

[ADDLED]

Also - as Chris says, the wort has more volume when cold than hot - by about 4%.

otherway round

Oops! It's the old "heat things up and they expand" trick!

Or freeze them... damn those treacherous water molecules

Thanks lads, much appreciated. I think i need to graduate my HLT to get a better reading; ive been filling it by first filling a Youngs graduated 5 gallon FV to 20 litres then pouring it in and repeatin to the right level, but it says on the side of those FVs that the measurements cant be relied on so i might not really be too accurate to start with.

I tell you whatthough, that Summer Lightning is far too easy to drink, so if my 6.5% version is half as nice its gonna be brain damage. Yum!

[edit1now]

Save pain and put a sight glass in your HLT, with felt-pen calibrations?

[ADDLED]

Save pain and put a sight glass in your HLT, with felt-pen calibrations?

Daabs sold em all tho ;[

[Aleman]

Oops! It's the old "heat things up and they expand" trick!

Actually between 0C and 4C water does contract when you heat it up . . . I know its bizarre but it does . . . it's the reason why pipes burst when the water in them freezes and expands

Completely irrelevant I know, but I couldn't help myself

[ADDLED]

Oops! It's the old "heat things up and they expand" trick!

Actually between 0C and 4C water does contract when you heat it up . . . I know its bizarre but it does . . . it's the reason why pipes burst when the water in them freezes and expands

Completely irrelevant I know, but I couldn't help myself

I see what you mean about burst pipes when water heats up, but I thought the reason pipes burst was because the water expanded as it froze, the pipe splits, theres no leak cos the ice seals the pipe and the gusher bursts when the ice thaws.

[edit1now]

A cheaper alternative to the sight tube - a calibrated stick. Use something which won't mind hot water (piece of nylon curtain track, piece of new, clean, wooden dowel or broomstick). Shove it in the HLT, add a measured quantity of water (weigh 2 litres or 5 litres on the scales - 1 litre = 1kg apart from several decimal places) and mark the stick with a felt pen. Repeat until bored.

[yashicamat]

Oops! It's the old "heat things up and they expand" trick!

Actually between 0C and 4C water does contract when you heat it up . . . I know its bizarre but it does . . . it's the reason why pipes burst when the water in them freezes and expands

Completely irrelevant I know, but I couldn't help myself

I see what you mean about burst pipes when water heats up, but I thought the reason pipes burst was because the water expanded as it froze, the pipe splits, theres no leak cos the ice seals the pipe and the gusher bursts when the ice thaws.

At the risk of extending this tangent even further, but I think that what Aleman is getting at is as the water temperature drops past 4 degrees C, it reaches it's maximum density, i.e., the total number of water molecules per cubic centimetre will be at its highest. If the pressure is equalised at this point, then the fittings closed, and then the temperature falls to freezing and below, there will be the maximum percentage expansion from the water and as a consequence - burst pipes.