
Elevate Construction Ep.334 - Dependence, Feat. Hal Macomber & Felipe Engineer
Are you ready to get schooled on production laws? In this special interview episode, Jason sits down with Hal Macomber (lean guru, chief operating officer at Nenan Company who did first Takt plan in 1999) and Felipe Engineer-Manriquez to unpack the production laws that govern construction. You'll learn why the order matters (overburdening, variation, then waste, not the reverse), Little's Law and small batch sizes (batch of 10 means 9 are idle, batch of 5 means 4 idle, batch of 1 means nothing idle), the law of bottlenecks (establish pace based on what bottleneck activity can do, everyone else falls in line), why variation stacks and compounds with dependence (0.9 reliability to 7th power is really small number, painter at end of long chain can't make up early slow starts), Kingman's formula (cycle time affected by capacity utilization and variation, if 5-day cycle time at 90% capacity with variation might become 8.5 days), how Taiichi Ohno purposely told Americans system focused on waste to maintain competitive advantage when real focus was flow, and the highway lane analogy (right lane high variation, left lane high utilization, middle lanes better because lower utilization can absorb variation).
What you'll learn in this episode:
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Why order matters: Muda/Mura/Muri (waste, variation, overburdening)—Hal told Jim Womack "you got it backwards, need to do overburdening first, then variation, then waste"; in construction there's already systemic pressure on people (Deming: worker trying to do best but system operating against them), remove overburden first to get capacity to look at variation, then remove waste to enable flow
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Little's Law and small batch sizes: Batch of 10 means at any point only working on 1 so 9 are idle; drop to batch of 5, only 4 idle; get to batch of 1, nothing idle—same number of people, goes through faster; implication: prepare work (make work ready for people, make people ready for work), when work ready and people ready, you have flow AND high productivity
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Law of bottlenecks: Every system has bottlenecks (capacity aspect—how much effort, how effective); with Takt establish pace based on what bottleneck activity can do, everyone else falls in line; Toyota Camry line ~90 seconds Takt time, only 15% of 100 operations operate at ~72 seconds, many in low 60s, some below 60, improving below-60 doesn't help flow, improving the dozen at 72 seconds improves speed of line
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Variation stacks and compounds with dependence: If reliable at 0.9 (90% PPC), 0.9 to 7th power is really small number; painter at end of long chain (20-25-28 operations) can't be high because of all that variation; superintendents mistakenly think slow start in year 1 of 4-year job can be made up in years 2-3-4—no, variation compounds, painter at end can't make up; Takt is countermeasure (train arrives every 2 days in different spot—no variation, no compounding)
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Kingman's formula: Waiting time = cycle time affected by capacity utilization and variation; 5-day cycle time at 90% capacity with variation might become 8.5 days; need to look at not just cycle time but cycle time with utilization and variation effects; Sellen Industries at Pentagon had 5.5 days but needed 5-day Takt, learned prefabrication to always get done in 4.5 days to absorb variation
"Variation stacks. Variation compounds with dependence. If you're reliable at 0.9, that's 0.9 to the 7th power, really small number. When you see PPC below 50% and people early in process are high, there's no way painter at end can be high because of all that variation. The painter bids the job based on experience, they don't lose money because they know it won't happen as planned."
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Also, here are links to our YouTube Channels:
· Jason Schroeder YouTube Channel: https://www.youtube.com/channel/UC4xpRYvrW5Op5Ckxs4vDGDg
· LeanTakt YouTube Channel: https://www.youtube.com/c/leanTakt
· LeanSuper YouTube Channel: https://www.youtube.com/channel/UCzQDevqQP19L4LePuqma3Fg/featured
· LeanSurvey YouTube Channel: https://www.youtube.com/channel/UC-Ztn3okFhyB_3p5nmMKnsw
