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A captive, two-part indexing jig for cutting 18° pie wedges in round tube. Clamp it on, cut, rotate, cut again — every cut lands where the last one did. No marker, no tape measure, no wrap-around template that slips halfway round the tube.
You can buy a printed jig, or you can own the file. Bend Brothers sell a printed pie cut jig from $66; the printed jig sets on Etsy run $22 to $95. Those are good parts — but they are parts. One size, shipped to you, and when it cracks you order another. This is a file. Print that size as many times as you need, forever, on the machine already in your shop, and print the next size at 11pm the night before a deadline.
What you download
- STL file for the size you choose, ready to slice — or the Bulk Pack with all 14 sizes in one purchase
- 1D centreline radius geometry, 18° per cut
- Instant download the moment you check out. Nothing ships, nothing waits.
Sizes
1.50" (38.1mm) · 1.66" (42.2mm) · 1.75" (44.5mm) · 1.88" (47.8mm) · 2.00" (50.8mm) · 2.15" (54.6mm) · 2.25" (57.2mm) · 2.50" (63.5mm) · 2.75" (69.9mm) · 3.00" (76.2mm) · 3.50" (88.9mm) · 4.00" (101.6mm) · 4.50" (114.3mm) · 5.00" (127mm)
How many cuts do I need?
At 18° per cut, a 90° bend takes five cuts. Fewest wedges, least welding, quickest build — the one to reach for on a long exhaust run where a slightly faceted radius doesn't matter. Drop to 15° or 9° when the bend is on show.
Print settings
My official settings for every G1Pro fixture: 2.5 mm walls, 2.5 mm top and bottom, 20% cubic infill, support-free, printed in Inland PETG-CF. Print one size first and check it on your tube before you commit a whole spool.
Licence — Shop Use
Buy it once and print as many copies as you like for use in your own shop, including on paying customer jobs. You may not share or resell the file itself, or print copies of the jig to sell. Need a print-and-sell licence? Get in touch.
Designed and drawn by James Goertz, G1Pro — building intake manifolds by hand since 2009, hundreds of them. These are the fixtures off my own bench.