In the second quarter, organic sales were up 31% with sizable gains in both our operating segments.
Similarly, orders were very good as we generated a book-to-bill of 1.3 times, with Aerospace driving that result.
Our total backlog stands at $984 million at quarter-end, reflecting a 12% increase from the end of the first quarter.
Adjusted operating income and margins were up 41% and 40 bps respectively.
Adjusted earnings per share were $0.45, up 67% from last year.
For the segment, orders were up 37% organically with a book-to-bill of approximately 1 times.
Industrial sales grew 42% with organic sales growth of 35%.
Now with expanding the ongoing semiconductor issue that's dampening automotive bills, IHS predicts -- still predicts 2021 global production to be up 10% over the last year and up an additional 11% in 2022.
Within our Molding Solutions business, we saw a good orders quarter up 17% organically.
Organic sales were up 22% year-over-year, while sequential sales were up 13%.
To maximize up time in an operation that runs 24 hours a day, seven days a week, the configuration of the mold allows for required maintenance of worn parts to occur right on the machine to replaceable modular units or clusters allowing for minimum disruption and production to come quickly back online.
At Force and Motion control organic orders were up over 50% with organic sales up double digits.
On a sequential basis, sales increased 6%.
As a result of this issue, we saw our second quarter revenue impact of approximately $5 million, very much aligned with the exposure we disclosed in April.
We expect the third quarter semiconductor revenue impact of $3 million and another $1 million in the fourth quarter.
We now expect 2021 to deliver organic growth of approximately 20%, better than our April expectation of mid-teens growth.
At Industrial, we see 2021 organic growth in the mid-teens with operating margins of 12% to 13%.
Aerospace sales improved 23% over last year and 6% sequentially from the first quarter.
A highlight of the quarter was our strong OEM orders which generated a book-to-bill of 2.5 times.
Segment operating margin is anticipated to be 13% to 14%, slightly higher than our April outlook.
Second quarter sales were $321 million, up 36% from the prior year period, with organic sales increasing 31% and foreign exchange generating a positive impact of 5%.
Operating income was $38.5 million versus $10.1 million a year ago.
On an adjusted basis, which excludes restructuring charges of $700,000 this year and $17.7 million last year, operating income of $39.2 million was up 41% and adjusted operating margin of 12.2% was up 40 basis points from a year ago.
Interest expense was $4.5 million, an increase of $600,000 as a result of a higher average interest rate, offset in part by lower average borrowings.
For the quarter, our effective tax rate was 25.3%, compared with 89% in the second quarter of 2020, and 37.6% for full year 2020.
Net income was $24.5 million or $0.48 per diluted share compared to $600,000 or $0.01 per diluted share a year ago.
On an adjusted basis, net income per share of $0.45 was up 67% from $0.27 a year ago.
Adjusted net income per share in the current quarter excludes $0.01 of restructuring charges and a net foreign tax benefit of $0.04, while the prior-year period excludes $0.26 of restructuring charges.
Second quarter Industrial sales were $235 million, up 42% from a year ago, while organic sales increased 35%.
Favorable foreign exchange increased sales by $12.4 million or 7%.
As has been the case since June of last year, we have delivered another sequential quarter of sales improvement with second quarter sales up 7% from the first quarter of 2021.
Industrial's operating profit was $27.3 million versus an operating loss of $300,000 last year.
Excluding restructuring costs of $200,000 this year and $15.8 million last year, adjusted operating profit was $27.5 million versus $15.5 million a year ago.
Adjusted operating margin was 11.7%, up 230 basis points from a year ago.
In the second quarter, we experienced approximately $1.5 million of combined freight and material inflation in the Industrial segment.
For the second half of 2021, our Industrial outlook includes $2 million of inflation impacts.
Sales were $86 million, up 23% from a year ago, driven by a 37% increase in our OEM business.
Our aftermarket business which continues to be impacted by lingering effects of the global pandemic, experienced a 2% sales decrease, with MRO down 8% and spare parts up 14%.
On a sequential basis, total Aerospace sales increased 6% from the first quarter of 2021.
Operating profit was $11.3 million, an increase of 8%.
Excluding $400,000 of restructuring cost this year and $1.9 million last year, adjusted operating profit was $11.7 million, down 5%, driven by higher incentive compensation and unfavorable mix.
Adjusted operating margin was 13.5%, down 400 basis points from a year ago.
Aerospace OEM backlog ended June at $694 million, up 16% from March 2021, and we expect to ship approximately 40% of this backlog over the next year.
Year-to-date cash provided by operating activities was $86 million versus $123 million last year, with free cash flow of $68 million, down from $103 million last year.
Capital expenditures were $18 million, down $2 million from a year ago.
Year-to-date operating cash flow in 2020 saw a $48 million benefit from working capital, as cash management with a significant focus during the pandemic.
Regarding the balance sheet, our debt-to-EBITDA ratio as defined by our credit agreement was 2.9 times at quarter end, down from 3.1 times at the end of last quarter.
Our second quarter average diluted shares outstanding were $51.1 million.
During the second quarter under a pre-existing 10b5-1 plan, we repurchased 100,000 shares at an average price of $52.29, leaving approximately 3.6 million shares remaining available for repurchase under the Board's 2019 stock repurchase authorization.
We now expect organic sales to be up 11% to 12% for the year, an increase from our prior view of up 10% to 12%, driven by strong Industrial growth.
FX is expected to have about a 2% favorable impact on sales, while divested Seeger revenues will have a small negative impact.
Adjusting op-- Adjusted operating margin is forecasted to be approximately 13%, consistent with our prior year.
Adjusted earnings per share is expected to be in the range of $1.83 to $1.98 per share, up 12% to 21% from 2020's adjusted earnings of $1.64 per share.
Our current expectation reflects an increase at the lower end of our previous range of $1.78 to $1.98 and we expect second-half earnings per share to be weighted to the fourth quarter.
Our interest expense forecast remains $16 million, while our other expense is forecast at $6.5 million, slightly less than our April outlook.
Estimated capex of $50 million, average diluted shares of $51 million and a full year tax rate of 30% are all consistent with our prior outlook.
Cash conversion is now anticipated to be greater than 110%, an increase over our prior expectation of 100%.

Summary:
Adjusted earnings per share were $0.45, up 67% from last year.
Second quarter sales were $321 million, up 36% from the prior year period, with organic sales increasing 31% and foreign exchange generating a positive impact of 5%.
Net income was $24.5 million or $0.48 per diluted share compared to $600,000 or $0.01 per diluted share a year ago.
On an adjusted basis, net income per share of $0.45 was up 67% from $0.27 a year ago.
We now expect organic sales to be up 11% to 12% for the year, an increase from our prior view of up 10% to 12%, driven by strong Industrial growth.