New BassChat 8"Cab design

[tauzero]

2 minutes ago, Phil Starr said:

Here you go two of the fane's in a 40l cab will do this with a fully rated amp driving 450W into the cab. That's a couple of db louder than most 12's. What it will need is a decent sized port as the amount of air that port will be moving at full power will be considerable. I've looked at using a 110mm soil pipe inside diameter 108mm 11.15mm longas a decent compromise. I'd be rear mounting the port so as not to weaken the front baffle too much.

 

 

If the port is 11.15mm long, surely that means it will be shorter than the thickness of the cab (assuming 12mm ply).

[rwillett]

I see that many people round the edges of the cab.

 

Is there a good reason for this please? Perhaps for the mottled finish or because the plastic corners assume so?

 

If so what's the recommended radii? 5mm?  12mm? Or just to take edge off?

 

Thanks. 

 

 

[Pea Turgh]

1 hour ago, rwillett said:

I see that many people round the edges of the cab.

 

Is there a good reason for this please? Perhaps for the mottled finish or because the plastic corners assume so?

 

If so what's the recommended radii? 5mm?  12mm? Or just to take edge off?

 

Thanks. 

 

 

I assume it’s to lessen the impact to your fingers when you walk in to some immovable object loading in.  I’ve got a hell of a lump on my little finger where I bashed it on a hand rail carrying a tumble dryer - if only it had rounded edges…

[Stub Mandrel]

2 hours ago, rwillett said:

I see that many people round the edges of the cab.

 

Is there a good reason for this please? Perhaps for the mottled finish or because the plastic corners assume so?

 

If so what's the recommended radii? 5mm?  12mm? Or just to take edge off?

 

Thanks. 

 

 

 

To stop chipping and make it more pleasant to handle. Very easy with a router.

 

Also paint won't take well on sharp corners. 

 

12mm is good.

Edited yesterday at 09:45 by Stub Mandrel

[rwillett]

1 minute ago, Stub Mandrel said:

 

To stop chipping and make it more pleasant to handle. Very easy with a router.

Fair enough...

[nekomatic]

Also because the plastic corners do need a rounded edge, or at least the ones I’ve used did. 

[rwillett]

1 minute ago, nekomatic said:

Also because the plastic corners do need a rounded edge, or at least the ones I’ve used did. 

I've printed mine and they assume a square edge. I think I'll do some rounding on the dges and do a redesign of them

Rob

[Obrienp]

10 hours ago, tauzero said:

 

If the port is 11.15mm long, surely that means it will be shorter than the thickness of the cab (assuming 12mm ply).

I have no expertise at all but I have the feeling it was a typo and @Phil Starr missed out a zero: 110.15?

[Chienmortbb]

3 hours ago, Obrienp said:

I have no expertise at all but I have the feeling it was a typo and @Phil Starr missed out a zero: 110.15?

That is about the length on the prototype. 

[RhythmJunky]

18 hours ago, Phil Starr said:

 

Edited 22 hours ago by RhythmJunky
Realised it'd been asked before. I hadn't refreshed the page...

[Mottlefeeder]

13 hours ago, rwillett said:

I've printed mine and they assume a square edge. I think I'll do some rounding on the dges and do a redesign of them

Rob

Bear in mind that wood with a paint finish will have a different overall radius to wood with a rat-fur finish.

 

I'd start with the corner radius and work out the wood edge radius to suit.

 

David

[Phil Starr]

23 hours ago, tauzero said:

 

If the port is 11.15mm long, surely that means it will be shorter than the thickness of the cab (assuming 12mm ply).

Cm 🥹😅

[rwillett]

9 hours ago, Mottlefeeder said:

Bear in mind that wood with a paint finish will have a different overall radius to wood with a rat-fur finish.

 

I'd start with the corner radius and work out the wood edge radius to suit.

 

David

Thanks for this. I've got some router bits with a decent curve 6mm and 12mm from memory. [Nope 3mm and 6mm after checking]

 

I've also got my identically sized spray booth to practise on so I'll see which size works best. 

 

I'll probably round the plywood, put the Armacab on and then design new 3d printed corners to fit. 

 

Redesign should be relatively easy. 

 

The only area I'm slightly puzzling over is the front as it's just 12mm of ply sticking out. Will look at what other people have done here. 

Edited 6 hours ago by rwillett

[tauzero]

15 hours ago, Phil Starr said:

Cm 🥹😅

 

Damn confusing metric units. Far simpler to use imperial: 0.00055426 furlongs.

[tauzero]

6 hours ago, rwillett said:

The only area I'm slightly puzzling over is the front as it's just 12mm of ply sticking out. Will look at what other people have done here. 

 

On the ones I've made (BC 112, BC 6" micro, my own Plenty), I've rounded the outer edge with about 12mm radius and left the inner edge as is. The micro cab (leatherette covered) has a cheapo round speaker-sized grille, the BC 112 (Tuffcabbed) and Plenty (leatherette) have metal grilles, and I've got a piece of aluminium grille for the 8" cab. https://www.ebay.co.uk/itm/362491694497?var=631653707862

Edited 13 minutes ago by tauzero

[tauzero]