bass trap "backers" too small ?

[LSP]

Hi,

I am assembling 6 bass traps made from using the tutorial posted on line by Ready Acoustics. I don't have a lot of wood building equip., so I had Lowes cut all the pieces for my frames, or "backers".

Silly me just assumed that since they were cut by a machine, they would be accurate, only to find out that 3/4 way through the assembly of said frames, some were a full 1/4" or so off!

Now I'm worried that when my 703 arrives this week, they'll be a problem with the fabric not fitting properly, or "tightly" due to the slightly smaller frame.

Hopefully it won't make that much of difference, but at the same time, I want to be prepared. Should I plan on cutting the 703 to fit exactly onto the frames, or just center the smaller frame inside the 703 panels, and secure to frame as usual?

I suppose I was just worried that if the cloth wasn't 100% snug to the sides of the 703(which seems to me would be the case, if the frames are a little smaller), the panels might shift a little to the right or left.

Am I being too OCD?

[PaulP]

Originally Posted by LSP

Silly me just assumed that since they were cut by a machine, they would be accurate...

Depends on who's operating the machine . Big box stores aren't known for the accuracy of their employees.

Am I being too OCD?

Yes.

Paul P

[SAC]

From the description I'm not sure what dimension is short - the length of the framing members, or their depth.

If it is the depth, one can easily add trim to make up the 1/4 almost in a face-frame manner using a few pre-drilled screws. Additionally, if you need to extend the length of the strips, a small spacer can easily be inserted and glued and attached with pre-drilled screws.

But in any case, as Paul acknowledged, you are worrying a bit too much. 1/4 or 1/2" variance is not the end of the world. And any 'looseness' in the material can be stretched, any slack removed, and then stapled in the rear. But if you do wish to modify the frames, it is not be very difficult.

[LSP]

Originally Posted by SAC

From the description I'm not sure what dimension is short - the length of the framing members, or their depth.

If it is the depth, one can easily add trim to make up the 1/4 almost in a face-frame manner using a few pre-drilled screws. Additionally, if you need to extend the length of the strips, a small spacer can easily be inserted and glued and attached with pre-drilled screws.

But in any case, as Paul acknowledged, you are worrying a bit too much. 1/4 or 1/2" variance is not the end of the world. And any 'looseness' in the material can be stretched, any slack removed, and then stapled in the rear. But if you do wish to modify the frames, it is not be very difficult.

The width of the frames are too short, as in, some wound up being 23.5, some were 23.75", instead of the 24" total they should have been. This is due to the short pieces (top and bottom) being cut short.

The problem I can see would be that when pulling the fabric tight over the 4" of panels, and stapling to the frame, the fabric won't fit snuggly against the sides of the panels, due to the (yet to arrive) 703 panels being 24" across, and the frames being 1/2 to 1/4 inches shy of 24". This may not make sense unless you're familier with the bass trap tutorial I referred to.

Also, the frames were wood glued, as well as screwed together, so adding shims isn't a possibilty.