Baffling Building
We are making baffles with standard R2.5 “EarthWool” insulation batts from Bunnings.
These batts come in two sizes, both being 90mm thick:
- 1160×430
- 1160×580
We will surround them with standard 19mm thick, 90mm wide pine. Corners will be braced with triangular MDF cut on the laser cutter to a design that makes it easy to line up the wood to 90degrees, and bang nails through quickly. We then insert batt into frame, wrap it with fabric, eg calico, which also happens to come in 1200mm rolls, and staple calico to frame. Quick! Easy!
Parts list
Required parts (smaller size option in brackets)
- 1 x 1160x580mm batt (1160x430mm batt)
- 2 x 1200mmx90mmx19mm pine. 1198mm if you want to be really picky. (same)
- 2 x 580mmx90mmx19mm pine. (2 x 430x90x19)
- 8 x MDF corner braces “SKoT's Superior Lovely Lasercut Patented Pine Bracing Brackets”
- 32 x nails and hammer
- wood glue optional on braces
- 1.5 meters of 1200mm calico - approximate - wrap first, cut afterwards! (1.15 m). You can use other material to suit your taste, just make sure you can breathe through the material - this is a test of its sound permeability.
- 100 or so staples and staple gun.
Assembly
- Measure your lengths of pine, mark cut with set square, mark “waste” side with cross hatching.
- Cut pine to length with hand tenon saw or drop saw, depending on your level of Adventure. NOTE: make sure you cut on the WASTE side of your marks - the cut will consume 2-3mm of wood. Allow for this!
- Position angle braces on LONG side bits of pine, hammer nails in. Do top and bottom, both sides. Braces are cunningly exact size for 19mm pine. Note “long side” brace nail holes are furthest apart. Optionally add a smear of glue on the pine where the braces will go. SMALL amount, spread with finger. Otherwise it gets slidey!
- Insert short side pine bits between end angle braces of large pine bits. Hammer ONE nail in. Check pine bits are at 90 degrees with set square. Hammer second nail in. Flip, nail other side - press your pine bits firmly together before adding nails.
- CHECKPOINT: You should now have a 4-side frame.
- Add one side of fabric. I suggest starting halfway down the edge-side of the frame to allow overlap. Attach one corner firmly, stretch along long side, attach second corner firmly, then staple mid point, then quarter points, then eighths.
- Attach fabric to opposite side of SAME FACE of frame. Start with on corner, with some stretching, then the other corner, then do all mid points, etc.
- Flip frame over, so fabric side is DOWN. It is now a Batt-Bathtub.
- Stick Batt in frame.
- Stretch fabric over the frame's batt-side, and staple corners, then mid points, etc
- Cut fabric - leave enough material to fully cover frame plus a few cm as a fold-n-tuck-under “hem”.
- Fold-n-tuck hem of fabric, attach with staples. Neat!
- CHECKPOINT: You have an acoustic panel.
Usage
How to attach to walls / ceiling? Try to reduce MECHANICAL COUPLING - transmits vibration.
- Suspended: you can use brass eyelet screws and fishing wire?
- bunnings have little 90-degree metal angle bits with screw holes - attach to wall and panel
- Ideally, have panel “floating' off wall by a few cm - then the backside of the panel can aborb sound too. Also reduces mechanical coupling of panel and wall. If suspending from ceiling, be even more generous - 10sm or more.
Decoration
- Custom material / fabric - check out http://www.spoonflower.com for all kinds of weird fabric.
- You can add strips of LED lights on wall or ceiling side for “backlit” effect
- You can add wooden grill or other pattern - will add back some sound reflectivity, of course.
- Paint the calico with ink or water colour or some other stain. You don't want to use paint that leaves a non-breath-through-able layer.