You are throwing your money away by solo mining. Go back to PPS mining and actually make some money.
Sorry to say but ja -- for at least over a year now, 61THs just cannot be counted on to make money when ran Solo.
Of course another point to be made is um, since serious $$ is involved you should be running the gear as a business! At least in the US the cost of equipment is a deductible business expense along with electric and such. The IRS considers them pure and simple as computers/servers, don't care what they are for other than they are a part of a business. Yes all income is subject to tax but the writeoff's can more than balance than out.
edit: Just for a income reference point, my current average 205-208 THs has brought in
BTC0.84 on CKpool from Feb 20 to the 23rd so um, Solo = NoNo at my size.