How to determine DME to fill in remainder of an LME recipe?

[jwic]

I have a smack pack of California Lager yeast in the fridge and I thought it was about time (after four kits) to see if I can concoct my own recipe.

From Palmer's HTB, the "specs" for Steam Beer are OG = 1.048-1.054 and
FG = 1.011-1.014. I was thinking about hitting the 1.052 mark for OG (52 pts. x 5 gal. = 260 pts.).

(here's where people should correct me if I'm wrong)

If LME yields 34-38 pts. per lb. per gal., I'd need 6.84-7.65 lbs. of LME.
(I went for the average: 36 pts. means I'd need 7.22 lbs. of LME)
If DME yields 40-43 pts. per lb. per gal., I'd need 6.05-6.5 lbs. of DME.
(I went for the average: 41.5 pts. means I'd need 6.27 lbs. of DME)

If I wanted to go with LME (7.22 lbs.) and I picked up two 3.3 lb. cans of LME (6.6 lbs.), I still need .62 lbs. more of LME. Because LME doesn't come in .6 lb. cans I was thinking of using DME for the remaining .62 lbs. since you can measure out the DME from a 1 lb. bag and save the rest for later.

(now onto my question)

Is it as simple as measuring out .62 lbs of DME or, because they yield different point values per pound per gallon, is there s'more math involved?


Thanks for indulging my question!

 

[Oldsock]

.62 lbs would get you close, but 36/41.5 would give you the conversion factor: .86 lbs of DME for each pound of LME. In this case you'd need .86*.62 = .53 lbs of DME. You're probably better off measuring the gravity contributed by the LME and then adjusting your DME addition accordingly (if you really want to hit 1.052 exactly). You may also want to assume a 5.25 gallon batch to account for losses to hops and transfers, so you actually get 5 gallons of wort into your fermenter at the target gravity. Some people assume even bigger batches so they get 5 gallons in bottles/kegs.

Good luck.

 

[jwic]

VERY helpful! Thank you so much!