3D Printing vs. a Store Run: A Putty Knife Cost Comparison
Total active effort: 7 minutes. The printer handled the rest (23 minutes of PETG stacking up while I went back to actual work).
Material cost: $0.17 in filament + a couple pennies of electricity. Rounded up: $0.20.
The Store Alternative
Nearest Home Depot: 5 miles away.
17 minutes each way + wandering + checkout time
= 40 minutes round-trip.
F-150 operating cost (IRS 2026 business rate):
$0.725/mile × 10 miles = $7.25.
Cheap plastic putty knife + tax: $1.05.
Subtotal before labor: $8.30.
The Expensive Part (Your Time)
| Expense | Store Run | 3D Printed |
|---|---|---|
| Item Cost | $1.05 | $0.20 |
| Transportation | $7.25 | $0.00 |
| Labor (@ $75/hr) | $50.00 | $8.75 |
| TOTAL | $58.30 | $8.95 |
Maybe you don’t cost your company $75 per hour. I’m sure you’re not free. There are laws against that (unless you’re an intern for a politician…and then you don’t need to worry about money or putty knives. You’ll need a much bigger tool to shovel manure).
Sorry about that side-track. Where were we?
Is a 3D Printed Putty Knife Any Good?
Yes — for a plastic putty knife. It’s stiff, flexes exactly where it should, and spreads compound or adhesive just fine. I’ve used it for two weeks with zero issues. (Printed in PETG for durability.)
Skip the Modeling — Download My Ready-to-Print File
Want to save even more time? I uploaded the exact putty knife model I designed to Printables.
→ https://www.printables.com/model/1438845-putty-knife
Just hit download, slice it, and you’re printing in under 5 minutes total. No Blender required.
(I modeled it myself because I enjoy the process, but 99% of people should just grab this file.)