My Side Port Binding Process (LONG)

Please put your pickup/wiring discussions in the Electronics section; and put discussions about repair issues, including fixing errors in new instruments, in the Repairs section.
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

My Side Port Binding Process (LONG)

Post by Eric Knapp »

Hi, All.

Here's my process for binding side ports. It's just how I am doing it after 5 trials. The next time will be on my current guitar builds. I'll probably change it over time but this is what's working for me now. I am a former teacher so I am going to show too much detail. I can't help it! Sorry about that.

It's starts with this form I made. It's 6 layers of 3/4" plywood that is a tapered ellipse. I don't know what the mathematical name for it would be. Elliptical cone maybe?
side-port-binding - 100.jpeg

It has about a 2º taper. I did the taper and shaping on my disk sander.
side-port-binding - 200.jpeg
side-port-binding - 300.jpeg

Then I trace the ellipse on the side. The pencil line doesn't need to be precise at this point.
side-port-binding - 400.jpeg

Next is drilling a hole and cutting out the ellipse well within the line.
side-port-binding - 401.jpeg

(Continued in the comments.)
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

Once I have the hole I will use a file to shape it a little.
side-port-binding - 402.jpeg

I shape it with a file until the form fits into the hole to about here.
side-port-binding - 600.jpeg

Then I put self-adhesive sandpaper on the form.
side-port-binding - 700.jpeg

Here I'm starting to use the form to shape the hole. It's like a perfectly shaped rasp.
side-port-binding - 800.jpeg

As I work the sandpaper on the hole the form fits farther into the hole. I move the sandpaper and keep shaping.
side-port-binding - 900.jpeg

(Continued)
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

I keep shaping the hole all around until the form fits like this without the sandpaper.
side-port-binding - 1000.jpeg

I now have a very nicely shaped elliptical hole with smooth sides that are tapered to match the form.
side-port-binding - 1100.jpeg

Now that the port is ready for binding I'll start making that. For these trials I started with a nice piece of curly maple from my stack.
side-port-binding - 1200.jpeg

I cut thin strips on the bandsaw. I believe that sawn veneer bends better than sliced. There are no micro-cracks from a slicing process. I cut the strips to about 1.5 mm (0.060").
side-port-binding - 1300.jpeg

I got a nice set of pieces from this stick.
side-port-binding - 1400.jpeg

(Continues)
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

Then I use the ole painter's tape and CA glue trick to attach them to a thin batten board.
side-port-binding - 1500.jpeg

Then it's off to the drum sander for thinning. I first get one side clear of saw marks. Then flip them for final thinning to size.
side-port-binding - 1600.jpeg

I have tried several thicknesses. I found that anything between 0.5 mm and 0.7 mm (0.020" and 0.028") will bend well. I tried thicker pieces with limited success. Every trial in my target range bent well.
side-port-binding - 1700.jpeg

All sanded and ready for bending.
side-port-binding - 1800.jpeg
The next step is to spray some Super-Soft on them and put them in a plastic bag. The directions on the bottle are for flattening veneer sheets. I figured putting them in between paper and board and clamping them was not necessary and that is correct for what I'm doing. I just soak them, put them in a plastic bag, and let them stay there overnight.
side-port-binding - 1900.jpeg

(Continues)
Last edited by Eric Knapp on Tue May 30, 2023 2:37 pm, edited 1 time in total.
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

Now we have the actual bending. I think a video would be much better than trying to explain what I do. In the video I'm using a heat gun on it's low setting. The high setting will burn the wood. The low setting provides plenty of heat.

https://youtu.be/OAT0_M44UhU

I do this for a good set of strips. I also bend some black veneer strips. I don't bother using Super-Soft on these, they bend easily.
side-port-binding - 2000.jpeg

I let them sit taped up until they are fully dry. I think I left them overnight this time. They retain their bends well.
side-port-binding - 2100.jpeg

Then I glue them together in this order.
side-port-binding - 2101.jpeg

I use the form again for the gluing. I put the laminations on the form and wrap them tightly with 3M auto-body tape. This is stretchy and compresses the binding well. I don't have a vacuum system and I'm not sure it would work well at this size. It might be better, I really don't know.
side-port-binding - 2200.jpeg

Here's the laminated binding after the glue sets and I take it off the form.
side-port-binding - 2201.jpeg

(Continues)
Last edited by Eric Knapp on Tue May 30, 2023 2:37 pm, edited 1 time in total.
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

The trickiest part of the process is cutting and shaping the scarf joint. I do this with the form in the side port hole. It's a cut-and-try procedure and is fussy. However, since the port hole is tapered there is some leeway and getting close seems to be good enough. Then I use the form as a wedge clamp to glue the binding to the port. The joint should be very good as the form was used for all steps. I'm getting a nice bead of squeeze out all around.
side-port-binding - 2300.jpeg

I made the strips about 7/8" wide as that was the width of the stick I had. It should work down to even 1/2".
side-port-binding - 2400.jpeg

Then I pull the form out after the glue sets and start trimming the excess.
side-port-binding - 2500.jpeg
Once I flush the binding I shape it with a slight round over. I do this with sandpaper. Adding some oil to the trial lets me see if I have success.


(Continues, just one more time!)
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

Here are some glamour shots of the final shaped binding.
side-port-binding - 2700.jpeg
side-port-binding - 2800.jpeg
side-port-binding - 2900.jpeg
side-port-binding - 3000.jpeg

Since this was all an experiment I am very open to suggestions on improvements to this process.

Thanks for giving this a look.

-Eric


(All done!)
User avatar
Barry Daniels
Posts: 3186
Joined: Thu Jan 05, 2012 10:58 am
Location: The Woodlands, Texas

Re: My Side Port Binding Process (LONG)

Post by Barry Daniels »

Wow! Great process Eric. I don't have anything to add.
MIMF Staff
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

Barry Daniels wrote: Tue May 30, 2023 6:07 pm Wow! Great process Eric. I don't have anything to add.
Thanks, Barry. That means a lot.

-Eric
User avatar
Barry Daniels
Posts: 3186
Joined: Thu Jan 05, 2012 10:58 am
Location: The Woodlands, Texas

Re: My Side Port Binding Process (LONG)

Post by Barry Daniels »

The tapered plug for shaping, laminating and gluing is genius.

Thanks for the tutorial. I know how much work that can be.
MIMF Staff
User avatar
Karl Wicklund
Posts: 244
Joined: Sun Jan 08, 2012 12:42 am
Location: NW Wisconsin
Contact:

Re: My Side Port Binding Process (LONG)

Post by Karl Wicklund »

First off, that looks great.
Second, I echo Barry, that’s a great process.
Third, that is a well-produced tutorial. Clear and thorough.
Thank you!
Kaptain Karl
Christ Kacoyannakis
Posts: 252
Joined: Sat Jan 07, 2012 8:58 pm

Re: My Side Port Binding Process (LONG)

Post by Christ Kacoyannakis »

Fantastic tutorial. I am thinking of using elliptical soundports on both the bass side upper bout and the side of my next archtop, so this is extremely helpful. I am trying to figure out which side to put the side port seam of the binding, towards the top of the guitar or the back. Initially I was thinking top, but then I reasoned that when the player looks down, it will be right there, so maybe back. I think if one were to use darker binding the seam would be even less noticeable, but yours looks very nicely done. Thanks for your educational efforts.
Darrel Friesen
Posts: 265
Joined: Fri Jan 06, 2012 5:48 pm

Re: My Side Port Binding Process (LONG)

Post by Darrel Friesen »

Great work Eric. There's more than one way to skin a cat.
User avatar
Bryan Bear
Posts: 1375
Joined: Fri Jan 06, 2012 1:05 pm
Location: St. Louis, MO

Re: My Side Port Binding Process (LONG)

Post by Bryan Bear »

Great tutorial thanks! Nice clean work too!
PMoMC

Take care of your feet and your feet will take care of you.
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

Barry Daniels wrote: Wed May 31, 2023 8:28 am The tapered plug for shaping, laminating and gluing is genius.
Thanks, Barry. I don't know where I got the idea but I suspect it has been done like this before.
Barry Daniels wrote: Wed May 31, 2023 8:28 am Thanks for the tutorial. I know how much work that can be.
I used to this for a living for my students. I had to explain complicated computer programming concepts to confused young adults. This one was really fun to do.

-Eric
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

Karl Wicklund wrote: Wed May 31, 2023 9:20 am First off, that looks great.
Second, I echo Barry, that’s a great process.
Third, that is a well-produced tutorial. Clear and thorough.
Thank you!
Thanks, Karl. A compliment from a fellow teacher is a treat.

-Eric
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

Christ Kacoyannakis wrote: Wed May 31, 2023 10:10 am Fantastic tutorial. I am thinking of using elliptical soundports on both the bass side upper bout and the side of my next archtop, so this is extremely helpful. I am trying to figure out which side to put the side port seam of the binding, towards the top of the guitar or the back. Initially I was thinking top, but then I reasoned that when the player looks down, it will be right there, so maybe back. I think if one were to use darker binding the seam would be even less noticeable, but yours looks very nicely done. Thanks for your educational efforts.
Thank you, Christ. I am still debating which side gets the scarf joint. That's why I did trials on a trial side so I could hold it like a guitar and see which way I liked better. I'm undecided. I also did this with a light wood on purpose. I always do trials of new things in light woods. When learning to do hand-cut dovetails I worked with pine. If you can make nice dovetails in pine then hardwoods are almost easy. Once I decide on what wood I'm using for the bindings on my current guitars I plan on using the same on the ports. Or at least something similar.

-Eric
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

Darrel Friesen wrote: Wed May 31, 2023 11:58 am Great work Eric. There's more than one way to skin a cat.
Thanks, Darrel!
User avatar
Eric Knapp
Posts: 620
Joined: Mon May 02, 2016 2:01 pm
Location: Wisconsin, USA
Contact:

Re: My Side Port Binding Process (LONG)

Post by Eric Knapp »

Bryan Bear wrote: Wed May 31, 2023 3:19 pm Great tutorial thanks! Nice clean work too!
Thanks for both comments, Bryan!
Dave Rickard
Posts: 6
Joined: Sat Jan 07, 2012 8:34 pm

Re: My Side Port Binding Process (LONG)

Post by Dave Rickard »

Super nice, Thanks for the tutorial
Post Reply

Return to “Flat-Top Acoustic Guitars and Bass Guitars”