Universal Sheet Metal Pattern Cutter, VOL2

“Surface development” or “surface pattern making” is the process of creating a 2d pattern for any shape that will be formed out of sheet material to create a 3d assembly.

The skills of surface development pattern making are important for decorative sheet metal, historic preservation, metal roofing, and copper work. Learning how to develop a pattern for any shape you would like to create can be useful for larger architectural forms as well.

One of the techniques used in pattern making is called “parallel line development”. This skill is vital for creating notching patterns for standing seam roofs.

The book, along with many other primary sources are hosted at The APT Library at the internet archive.

Spengler TV

Spengler is the official trade name in Germany (and maybe some other countries) for metal roofing. I’ve watched this channel grow up on Youtube, and wow they have added a lot of content! Metal roofing and standing seam, are codified by law there. This means everything last longer, there are fewer repair and maintenance cost. And on the market side: it means everyone has to play by the same rules, much like a bar or medical association. They study and master the techniques in secondary school. This is miles above “on the job” training, or even union training here in the US. Since union training is still focused more on meeting the “market” production demands.

Seaming a pipe stack to a long-pan metal roof. Skip to 5:00 to see the action!


This forum, on FB is absolutely one of the best sources for information and example photos for permanent, standing seam roofing. We rely on the translator service as almost nobody speaks english. Back in 2012, when I was studying folding and joinery techniques (with zero online resources in english) I used to pull the text one-by-one from PHP forums and paste into google translate. This is so much better as we can actually communicate; although it is somewhat broken.

This photo shows a really interesting valley concept, and the debate ensues… What is so unique and showy about this approach is that one whole side of the field had to be installed, and turned up. When the opposing side was installed: since the seams have to run in to and past the valley, it means they had to deform every field seam down, and lay them all over all the way up, so the pans would sit flush on the field. This is working blind. After that, they would have to close all of the connecting seams, and dress it down to fold the valley.

A member, posted a detail which is similar but with a batten-cap, and square seam

Kevin finished the diamond turtle! FB folders rejoice.

Great project from New Jersey metal master and tradroofing.com student: https://www.facebook.com/kevin.rosselli.39

Kevin, musing on the inevitability of the next roofing crew causing damage to this, which can and should last the lifetime of the building. It brought to mind, one of my early works that was later destroyed by an eager insurance claims industry. Ready to sell work that was un-needed because of “dents”

This roof, completed by my company: Patina Slate & Copper, was destroyed by overzealous “hail damage” sales tactics, and ignorance. Only a few years after installation: in spite of being perfectly sound. The contractor who ended up doing the work sought me out to get up training on standing seam, however it was much after this roof. Truly a crime.

tradlive is back! feb23

hey folks. I’m firing this thing up again, in an attempt to get back to automated live streams / posting… lord help me. just field testing right now so don’t expect too much. @ me for #quickmaths #roofmaths #lifeadvice #insults

who’s still watching in 2019

hip patterns series 4:12 and 6:12

Over my time in the shelter from November, thru the beginning of February, I worked on these hip patters. These are useful for creating folded hips on a standing seam copper roof, although any light gauge material that will not rust can be used. Eventually I will get them all scanned and available on an index page. One-off patterns are always available. Contact for metal roofing design and pattern work!

Print out the PDFs and align to the un-formed pan end.

Print out the PDFs and align to the un-formed pan end.

Print out the PDFs and align to the un-formed pan end.

Print out the PDFs and align to un-formed pan end

Learn to fold metal roofs!

In 2015 I left Rhode Island, and Casa Buena Builders to bring seamed roofing to the english-speaking world. I had been studying at night, bringing my skills up with folding and joinery; while working full-time in historic preservation, remodeling, and slate roofing. My favorite project of the tour that year was this seminar I was invited to give at the HPTC (Historic Preservation Training Center) headquarters in Frederick, MD.

Almost all of these techniques were completely foreign to the seasoned pros from the National Parks Service. I hope to one-day have all of these rules codified in English, and accepted at least internally within organizations like NPS. We may never be able to regulate the entire market like the better countries but within institutions and even preservation districts it is possible. I know all properties benefit from having roofs that are designed to last as long as the building.

This handout (PDF link) below demonstrates how to layout and cut the valley seam, from the ground as long as you know the two pitches of the intersection roof faces. This is very important with metal roof seaming. Much like in timber framing: the piece must be fully fabricated to exact specifications before they are assembled. In the same way: we do most of our design and layout on the drawing board, and on the cutting bench. There is very little “in place” fabrication, only folding assemblies.