Building a new foldable Acoustic Panel

[Flint]

With my new rig being stereo only, I can finally do something about reflections off my flat panel TV. Before now, the center channel make it hard to do something simple and affordable to address the TV, but now I can permanently place a panel on the floor in front of the TV which flips up to cover the TV when I am listening to music only, and flip it down when I am watching TV.

So, I designed recording studio Gobo style free standing dual panels which are connected together at the top with a hinge so I can flip up one of the panels to rest on top of the other. I'll post drawings and photos of the project once I am done, or as I can while I wait for paint to dry.


Fun times!!!

 

[TitaniumTroy]

How about a video of you watching the paint dry, that might be exciting. Okay just kidding, I look forward to seeing whatever you come with up.

 

[Flint]

Well, it's drying now. Tomorrow I should be able to stretch fabric over the face frames.

 

[Flint]

I'll post my drawing of the design in a bit.

 

[Flint]

Alright - this is the drawing I am building from. I used Pine for the wood, sold as 1 x 6 pieces, which are really 3/4 X 5-1/2 in reality.

The internal blocks are 3-1/2" deep, so there is 1" from the front and rear edge to the block face, and the frames for the fabric are 3/4" thick, making a small 1/4" difference from the front edge of the side to the face of the fabric.

The plan is to make two identical panels hinged at the top, one with the feet/legs and the other free to flip up to make a taller unit.

I am using cotton insulation Heeman introduced me to. It is less stiff than Owens Corning 703 sheets, but it has better acoustical properties in the upper bass, which is a good thing. I bought 2" thick rolls and plan to place two layers between the fabric wrapped frames. If I find the cotton seems like it will droop or loose the proper shape, I can put a layer of something stiff, like window screen, between the two 2" sheets.

That's the plan.

I have not determined how I will affix the top panel when it is upright, I am hoping that it will be stable without any mechanical restraint. But, if it doesn't seem safe, I will figure something out.



The leftmost drawing is the panels flipped on top of each other from the side with the leg which would be at the front removed in the drawing. The rightmost drawing is one panel with no fabric or acoustic material with the front frame removed so I can place the blocks.

 

[Flint]

I will add that I am certainly going to make minor changes to the actual build. In fact, the drawing above had to be edited to capture several changes I already made while building which rendered my first drawings inaccurate. For instance, I know I will need to stand off the legs from the panel they are connected to in order to ensure the swinging panel clears them, assuming they will not be perfectly square (a little gap of at least 1/8" between each side of the swinging panel and the inside of the legs is a good idea, and it'll be easy to implement). I will also put some sort of foot at the front and rear edge of the legs to ensure they are stable on carpet. I am also going to use a chisel or router to countersink the hinges into the two panels so the two stack perfectly when flipped upright.

 

[Deerhunter]

cotton insulation Heeman introduced me to.

Do tell more, I must of missed that post.

 

[Flint]

Do tell more, I must of missed that post.

Nope, you didn't miss any posts. Heeman and I actually communicated outside of this forum. Imagine that!!!

I was looking into where I could buy 2" thick sheets of Owens Corning 703 for these panels and bemoaning the fact that since this will be a often manipulated acoustic panel, as I'll be flipping up and down the front panel throughout the week, that Fiberglass could more likely escape into the room. Loose strands and specs of fiberglass could make things itchy, scratchy, and so on. So, I was considering other options and Heeman told me about Denim Cotton Insulation.

So, I ordered a few cases of this:
https://www.homedepot.com/p/UltraTo...lti-Purpose-Roll-6-Pack-60306-16482/202710055

It is a roll of 16" wide by 48" long and 2" thick cotton insulation which has very good acoustic properties. Buying it at Home Depot for in store delivery made it so I didn't have to pay shipping costs. In fact, I strongly recommend Home Depot for OC-703 as they have a great online selection and shipping to your nearby store is free. I love that!!!

So, there you go.

 

[Flint]

For the fabric I am wrapping around the frames on the front and rear of each panel I purchased flat sheets from Walmart made of 100% cotton in the color I wanted. Two twin sized sheets, which is probably way more than I need, was only $12. I used to buy proper fabric in the fabric section, but that stuff costs more and I am only using this stuff to hold back the insulation and look decent. As long as they are a relatively loose weave natural fabric, like cotton or linen, they are great for this application.

I am about the stretch then staple the fabric to the frames, but first I am going to iron them so get any semi-permanent creases out of them.

 

[Deerhunter]

FLINT

How dare you talk to people out side of this place with other members!

I did not give you permission to do that, yep you must ask of first! For that you have been issued a gag order, till further notice.

This only extends to talking to members outside of the forum.

 

[Deerhunter]

I will have to check that out. I hate working with glass. I used to work for a ship making place called Delta Marine. We made multi million dollar yachts. I made the hulls, bulkheads, water tanks all fiberglass.

Then once I got home I would take the coldest shower I could stand, it sucked!

 

[Flint]

Defying the ban, I'll take the chance, the sheets were not ironing well, so I decided to wash them. Then I'll iron if needed before cutting to fit the frames.

 

[Flint]

Here's some progress photos.

This is one of the two outer frames after gluing up before routing the edges with a 1/8" round-over bit, sanding, and painting:


Here's the two outer frames and the four front and rear frames I'll stretch fabric over.


Here's most of the frame pieces after sanding and the first pass at painting as the paint is drying:


I placed the two outer frames against each other as they will be used and mounted the hinges with one screw on each half, then used a silver sharpie to mark the outline of the hinges to use as guides for my plunge router to countersink the hinges:


Here's one of the outer frames after the final coat of paint:

 

[Flint]

Finally, for today while I wait for the paint to finish drying...

I stretched the fabric over the front and rear frames and they are ready to go. I pre-drilled the holes for the screws I will use to mount them to the blocks inside the outer frames:

 

[Flint]

Now I need the paint to dry overnight and I hope to mount the legs/feet to one of the outer panels. Then I can put the insulation in and mount the fabric panels. The last step is installing the hinges and they are done!!!

 

[PaulyT]

Cool.

 

[Flint]

As for the paint... I used cheap Krylon black paint for the inside of the outer frames, aiming only at the areas near the edge which might be visible under specific conditions, and for the outward facing side of the frames for the fabric. In the exposed sides of the outer frames I used a higher quality "satin" Dark Walnut spray paint from Krylon which is dark enough to appear black, but the slight brown tint makes it look a tad classier than just plain ol' black.

 

[Deerhunter]

Nice

 

[Flint]

I am contemplating putting some sort of handle on the back side of the top piece, so that when it is folded down I can easily grab the handle to lift it up. When it is up, the protruding handle will add weight to the back of the panel, away from the hinges, and might add stability to the stack and preclude me needing some sort of fixture to hold it up safely.

 

[Flint]

Yesterday I put the legs on the lower panel outer frame:



I then touched up the paint and it is still drying in my garage this morning.

I designed a handle to raise the upper panel and have all the material I need for it. So I hope to work on that today.