Metric Hat Making Tool Rounding Jack Brim Cutter Collector Edition Brass Blade Holder Walnut Laser

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Project by Mark A. DeCou posted 09-30-2011 05:50 PM 8586 views 4 times favorited 8 comments Add to Favorites Watch

Project: Handmade walnut and brass rounding jack for hat makers to cut the brim to size.

Project Story:
Recently, two different Milliners (custom hat makers) ordered my Collector’s Edition Rounding Jacks through my online store

The first lady from Berlin, the other lady from Bucharest, and being across the Pond, they both requested that I incorporate a Metric Unit ruler on the tool. I already had quite a few engraved English unit rulers on hand, but agreed to the change for a small fee to pay for the extra engraving cost.

Here is Gabriela's FaceBook Page, she is a tremendously talented and creative Romanian Hat maker.

The economy has taken out the laser engraver that I used before, so I found a new one that worked with me this month to develop the Metric Ruler graphics and engrave the wooden parts for me on a quick turnaround, tiny volume order, they are right here in my area, and great to work with. Wow, that combination doesn’t happen often in this world.

This rounding jack cuts the brim on a hat to size, using the crown oval curve as the basis, so that the brim cut mimics the curve of the crown oval. The adjustable brass front shoe allows setting the tool to do a “dimensional brim”, which is a hat term for cutting the sides wider than the front/back, which was common on many Fedora hats back in the day. I don’t make hats, but I make a long list of hat making tools, and it has kept me in business the past 3 years when the economy killed the expensive furniture buying craze.

I keep my mind occupied with these hat tools, by dreaming up new designs, and solving various problems that hat makers call me about. Some of my tools are copies of tools used in the mid to late 1800’s, while other tools are a completely new concept. I tend to use more of my mechanical engineering background in these hat making tools than any other product I’ve made over the years. I strive to make each one perfectly functional, and also pleasing to look at and hold in your hand. And, like I said, it’s kept me in business, so thank you God.

The rounding jack is my own design, based on some antique models that I researched and tore apart some years back. I analyzed 8 historical examples, and figured out why they all broke, or fell apart with years of use. I improved on those issues, expanded the capacity to include wider brim cutting for milliners, and angled the blade position for a better slicing action. I’ve sold a lot of these rounding jacks in the past 5 years, and I have something like 8-10 different models and sizes, which have different features and associated costs.

I do all of the brass machining and all work (except the laser work) myself in my own little shop here in Kansas. I enjoy the chance to work in metal, and I think the color contrast with the walnut looks nice, and gives the tools a vintage appeal, similar to tools made before the industrial revolution, which appeals to my hat making clients.

I’m happy to say that this Rounding Jack is on it’s way to Bucharest, Romania and the Berlin, Germany shipment will be ready next week.

Here’s to happy hatmaking across the big Pond!

thanks for looking,
Mark DeCou


Video: What does this thing do? Watch this video by California Custom Hat Maker Tom Gomez from Premier Panama Hats using one of my Rounding Jacks on a felt body Hat. Shown in the video is a Collector’s Edition Brass Blade Model, Tom used to cut his first Felt Hat brim. If you like his work, follow this link to Tom's Gomez Hat Company Website

To See More Hatmaking Tool Videos from Tom Gomez:
  1. Foot Tollikers: click here to see
  2. Kettle Curling Tool: click here to see one
  3. Puller Downer: click here to see one:
  4. Pusher Downer: click here to see one

Here is a Slideshow with more of my Rounding Jacks Shown
Click the “Speaker” icon for music


Artisan Hat Tools by Mark DeCou Studio
(Do you want to see More? Just follow these links):

ARE LISTED IN MY ETSY.COM ONLINE SHOP, click here to check inventory

Rounding Jacks, Collector’s Editions:
  1. Ebonized Walnut Clockwise with Laser Engraving
  2. Walnut Counter Clockwise w/Laser Engraving
  3. Walnut Uni-Directional Cutter
Rounding Jacks, Deluxe Model:
  1. Maple Deluxe Model, Counter Clockwise Cutter
  2. Maple Deluxe Model, Clockwise Cutter
  3. Walnut Deluxe, Counter Clockwise Cutter
  4. Walnut Deluxe, Clockwise Cutter
Rounding Jacks, Hobbyist-Hatter Model:
  1. Walnut Hobbyist-Hatter Model, Counter Clockwise Cutter
  2. Walnut Hobbyist-Hatter Model, Clockwise Cutter
Bench-Top Display Stands for Rounding Jacks:
  1. Walnut Bench-Top Display Stand
  2. Oak Bench-Top Display Stand
    Click here to check inventory
Customized Rounding Jacks, Personalized for Specific Hatters:
  1. Spradley Hats in Apline, TX
  2. Rachel Pollock of La Bricoleuse
  3. Brainpan Hat Shop in Sumner, WA
  4. Steve Delk's Adventurebilt Hat Co.
  5. Marc Kitter's Adventurebilt Hat Co.
  6. Pyrate Trading Co.
  7. Hatman Jack at Wichita Hat Works
  8. Inaaya Hat Co.
  9. Penman Hat Co.
Formillons & Conformateurs:
  1. Complete Restoration of a Maillard Conformateur and Formillon
  2. New DeCou Formillion & Conformer, Prototypes #1 & #2
  3. Custom Designed Conformateur Carrying & Storage Case
  4. New Plot Base Board for the Maillard Allie Formillon
  5. Maple Wrench for Tightening Formillon Thumbnuts
Foot Tollikers:
  1. Left-Handed & Right-Handed Foot Tolliker
  2. Foot Tolliker: Elk Antler & Birch Wood, on a Display Stand
  3. Foot Tolliker: Walnut Wood, on a Display Stand
  4. Foot Tollikers: Three in White Birch Wood
  5. Foot Tollikers: Walnut Wood Set of Four
  6. Foot Tollikers, Birch Wood Double Set, on Display Stand
Brim Edge Curling Tools:
  1. Hinge-Shackle Curling Tool for the Homburg Hat
  2. Full Circle Shackle Curling Tool
  3. Half Circle Shacking Curling Tool
  4. Groove Tolliker Curing Tool
Band Blocks:
  1. Thick Poplar Wood, Various Sizes and Oval Shapes, with Tapered Sides
Crown Blocks
  1. Long Oval Crown Block Sculpting Work
Hat Block Spinners:
  1. Late Turned Hat Block Spinners
Flange Stands:
  1. Heavy Duty Flange Stands
Puller Downers:
  1. Puller Downers
Pusher Downers:
  1. Pusher Downers
Hat Racks, Hat Stands, & Cedar Band Blocks:
  1. Hat Racks to keep oval shapes
Stainless Steel Slip Stick:
  1. “Coming Soon”, please check back.

(Note:This project story, project design, and photos are protected by copyright in 2008-2010 by the Author, M.A.DeCou., all rights reserved, no use allowed without expressed written permission.)

-- Mark DeCou - American Contemporary Craft Artisan -

8 comments so far

View MasterSergeant's profile


1441 posts in 3969 days

#1 posted 09-30-2011 06:22 PM

WOW! interesting, I have learned something today, THANKS!!

-- Kelly, woodworker under construction

View mpounders's profile


1008 posts in 4176 days

#2 posted 09-30-2011 06:44 PM

Those are gorgeous! Beauty and function in one nice package.

-- Mike P., Arkansas,

View TonyWard's profile


748 posts in 5609 days

#3 posted 10-01-2011 12:52 AM


Nice to see you are still alive and well. It is particularly nice to see you found a niche market in which you are able to use your expertise – Well done!

Heres to the day when the demand for your fine furniture arrives!

View Karson's profile


35279 posts in 5681 days

#4 posted 10-01-2011 01:02 AM

Mark: Congratulations. Becoming world renown.

-- I've been blessed with a father who liked to tinker in wood, and a wife who lets me tinker in wood. Appomattox Virginia [email protected]

View Napaman's profile


5535 posts in 5358 days

#5 posted 10-01-2011 05:26 AM

world renown…there is no one who deserves it more! great stuff as always.

-- Matt--Proud LJ since 2007

View Michael1's profile


403 posts in 3941 days

#6 posted 10-01-2011 05:58 AM

That is really neat. How did you get into hat making tools if you dont make hats? That seems like it must have taken alot of research to know that your tools would have a need. They look absolutely wonderful and if I were a hat maker I am sure I ould love to have your tools in my arsenal.

-- Michael Mills, North Carolina,

View grizzman's profile


7836 posts in 4584 days

#7 posted 10-01-2011 06:41 AM

what a great tool, its things like this that help you stay afloat and put p and j on the table…grizz

-- GRIZZMAN ...[''''']

View Lee A. Jesberger's profile

Lee A. Jesberger

6875 posts in 5260 days

#8 posted 10-01-2011 04:44 PM

As always, great job Mark.


-- by Lee A. Jesberger

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