Knotty Flag Company’s First Precision Board HDU Shop Sign

Coastal Enterprises, manufacturers of Precision Board HDU, is proud to host guest blogs written by some of the signage industry’s biggest movers and shakers, posted to the Precision Board Blog.  This guest blog is written by James Matthius with Knotty Flag Co., based in Staten Island, New York.  James tells us how he killed two birds with one stone by making his first shop sign AND fabricating it from Precision Board high-density urethane, his first time making a sign out of HDU.  We think the results speak for themselves!


Q & A with James Matthius…

How did you hear about Precision Board HDU?

Mike who is a fellow woodworker, and owner from Veteran Wood Co. and put me onto the HDU scene. He’s been very inspiring to me and super helpful. I saw him making really awesome signs, and said I got to try this stuff out.

Tell us about your project?

I have been wanting to make a shop sign for myself for the longest time, just never had the time to do it. When I finally got my hands on the Precision Board HDU I figured why not treat myself and give it a shot. I used pocket tool paths with texturing to make the background pop. I love the way the texture looks on HDU.

What density of Precision Board did you use?

PBLT-15…15lb urethane foam.

Tell us what you used for a router, bits and software for this project?

For the router I used a Carbide 3d router.  I ended up finishing with the Makita trim router. All of this was done on Carbide Create software. I’m still learning Vectric Aspire software. Huge learning curve for me. I just got into the CNC world in December 2019 so I’m learning as I go with the help of fellow CNCers. For the bits I went with all Amana tools foam upcut endmills from Tools Today. I used 1/16 to line out the company name, and a 1/8 bit to do the texturing pocket cuts.

How long did it take to cut the board?

Wooof lol, I’m a little embarrassed to admit this. All in all it was about 22 hours! I later learned how to use different bits and separate sections into different tool paths.

Tell us about the priming and painting of the sign?

I used Kilz latex WB primer and used regular arts and crafts store acrylic paints for the top coats. Actually worked out pretty well. Next time I’d like to use higher end finishes.

How will the sign be mounted?

The sign will be fixed to a wooden backer board with a frame built around it, all made by me of course. I used Total Boat Epoxy Resin to fix it to the backer itself.

You said this was your first time using HDU. Any tips or tricks you discovered while making the sign?

Tips and tricks. I’d like some myself!! Definitely do your research for toolpaths, feeds/speeds. Dust collection is a must. It’s a little pricey, so if you are unsure, run a test pass on something else to make sure your design comes out the way you want it to.

Why do you like Precision Board HDU?

I like the light weight of it, the machinability of it, the fact that it’s weather resistant and the way textures come out.


James started out doing woodworking, making furniture and home decor pieces for himself, friends, and family. Everyone always loved what he could create for them. He said to himself,  why not try and start something and see where it goes. So here he is giving this a go creating beautiful furniture pieces and decor for everyone! CNC and sign making is his new obsession.  He loves everything about it and is very pleased and thankful for all the support that he’s had so far from his customers and friends!  The Knotty Flag Company can be found on Instagram and on their website.

Coastal Enterprises manufactures Precision Board HDU, a versatile, cost-effective and eco-friendly urethane sign material that is particularly suited for making professional-looking indoor and outdoor dimensional signs.  It is a closed-cell rigid substrate that does not rot, warp or crack.  You can request free samplesget a quote or sign up for periodic newsletters packed with helpful information.