Speakerplans.com Homepage
Forum Home Forum Home > Plans > New Projects Forum
  New Posts New Posts RSS Feed - B&C 8PE21 horn
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

B&C 8PE21 horn

 Post Reply Post Reply Page  <1234>
Author
Message
Robbo View Drop Down
Old Croc
Old Croc


Joined: 05 December 2005
Location: Shropshire
Status: Offline
Points: 4221
Post Options Post Options   Thanks (0) Thanks(0)   Quote Robbo Quote  Post ReplyReply Direct Link To This Post Posted: 25 January 2019 at 11:02pm
I agree totally with all of the compliments above as it does seem ages since we had an epic build on here---But(theres always a but) I just had a thought that it may have been easier to make a jig and make them out of fibreglass, especially if more are going to be required in the future.
Back to Top
luthier View Drop Down
Registered User
Registered User
Avatar

Joined: 21 July 2013
Location: UK - London
Status: Offline
Points: 271
Post Options Post Options   Thanks (0) Thanks(0)   Quote luthier Quote  Post ReplyReply Direct Link To This Post Posted: 25 January 2019 at 11:08pm
Quality work there! 
Back to Top
boots-hifi View Drop Down
Old Croc
Old Croc
Avatar

Joined: 15 August 2011
Status: Offline
Points: 2460
Post Options Post Options   Thanks (0) Thanks(0)   Quote boots-hifi Quote  Post ReplyReply Direct Link To This Post Posted: 26 January 2019 at 12:05am
Maybe fibre glass would of made sense, but let’s face it if you can produce wood work at this standard its an art form. I’d love to hear them!

Edited by boots-hifi - 26 January 2019 at 12:21am
Back to Top
MattStolton View Drop Down
Old Croc
Old Croc
Avatar

Joined: 04 September 2010
Location: Walthamstow
Status: Offline
Points: 4234
Post Options Post Options   Thanks (0) Thanks(0)   Quote MattStolton Quote  Post ReplyReply Direct Link To This Post Posted: 26 January 2019 at 10:14am
Top skills, love a biscuit or two!
Matt Stolton - Technical Director (!!!) - Wilding Sound Ltd
"Sparkius metiretur vestra" - "Meter Your Mains"
Back to Top
catalin View Drop Down
Registered User
Registered User
Avatar

Joined: 02 April 2012
Location: London
Status: Offline
Points: 152
Post Options Post Options   Thanks (0) Thanks(0)   Quote catalin Quote  Post ReplyReply Direct Link To This Post Posted: 26 January 2019 at 6:10pm
Hi everyone!
Most of my knowledge abaut sound sistems is from Speakerplans Forum,important is not to rush things,be patient and know your limits
Allso is important to understand what you are doing , building something without know how is working is nonsens to me

And,yes,great people araund here which share their knowledge (sometimes with to much patience!)
Speakerplans is the place to be!!
Thank youSmile!!

Back to Top
catalin View Drop Down
Registered User
Registered User
Avatar

Joined: 02 April 2012
Location: London
Status: Offline
Points: 152
Post Options Post Options   Thanks (0) Thanks(0)   Quote catalin Quote  Post ReplyReply Direct Link To This Post Posted: 27 January 2019 at 4:46pm
Sunday playSmile








Back to Top
studio45 View Drop Down
Old Croc
Old Croc
Avatar

Joined: 16 October 2007
Location: United Kingdom
Status: Offline
Points: 3863
Post Options Post Options   Thanks (0) Thanks(0)   Quote studio45 Quote  Post ReplyReply Direct Link To This Post Posted: 27 January 2019 at 5:01pm
When I made horns like this years ago, I had a lot of trouble with the calculations for the compound mitre angles on the flare pieces. I didn't get it quite right and ended up with small gaps. Could you possibly explain how you worked them out?
Studio45 - Repairs & Building Commotion Soundsystem -Mobile PA
Back to Top
catalin View Drop Down
Registered User
Registered User
Avatar

Joined: 02 April 2012
Location: London
Status: Offline
Points: 152
Post Options Post Options   Thanks (0) Thanks(0)   Quote catalin Quote  Post ReplyReply Direct Link To This Post Posted: 27 January 2019 at 5:29pm
Well,yes ,it is tricky,it was more like test and try
I had to sacrifice few bits of ply ,till i get it right
Back to Top
bob4 View Drop Down
Old Croc
Old Croc
Avatar

Joined: 29 February 2004
Location: Finland/Germany
Status: Offline
Points: 1842
Post Options Post Options   Thanks (0) Thanks(0)   Quote bob4 Quote  Post ReplyReply Direct Link To This Post Posted: 27 January 2019 at 5:46pm
Originally posted by studio45 studio45 wrote:

When I made horns like this years ago, I had a lot of trouble with the calculations for the compound mitre angles on the flare pieces. I didn't get it quite right and ended up with small gaps. Could you possibly explain how you worked them out?


One possibility is to cut slightly oversize and do the final trimming with a well tuned hand plane. You would be amazed at the amount of accuracy you get with a little bit of practice!
Back to Top
luthier View Drop Down
Registered User
Registered User
Avatar

Joined: 21 July 2013
Location: UK - London
Status: Offline
Points: 271
Post Options Post Options   Thanks (0) Thanks(0)   Quote luthier Quote  Post ReplyReply Direct Link To This Post Posted: 27 January 2019 at 7:15pm
I often cut compound mitres with my ts55 track saw, hand planes have their place, but they're not practical time wise if you're making multiples. 
Back to Top
snowflake View Drop Down
Old Croc
Old Croc


Joined: 29 December 2004
Location: Bristol
Status: Offline
Points: 3118
Post Options Post Options   Thanks (0) Thanks(0)   Quote snowflake Quote  Post ReplyReply Direct Link To This Post Posted: 27 January 2019 at 8:41pm
Originally posted by studio45 studio45 wrote:

When I made horns like this years ago, I had a lot of trouble with the calculations for the compound mitre angles on the flare pieces. I didn't get it quite right and ended up with small gaps. Could you possibly explain how you worked them out?


you can calculate them using trignometry and I have done so in the past. I can't quite explain it without drawing it all out though - it involves multiplying the angles by cos or sin of the flare angles. there's a calculator on this page under 'general compound angles 2'


edit:
for a square horn the bevel=45-(((invsin(cosAcosB))/2)

how you do it for a horn with more than four sides I can't quite get my head round




Edited by snowflake - 27 January 2019 at 9:23pm
Back to Top
doller View Drop Down
Young Croc
Young Croc


Joined: 19 July 2014
Location: japan
Status: Offline
Points: 509
Post Options Post Options   Thanks (0) Thanks(0)   Quote doller Quote  Post ReplyReply Direct Link To This Post Posted: 28 January 2019 at 3:54am
It's near impossible with a hand circular saw. They only bevel one way and it's always the wrong way. Cutting perfect matching panels near impossible. I am sure a few can do it.
The best way is to make an angled cut off jig for the table saw. You can get exactly matching panels. But yes it does always take a bit of trial and error.

Back to Top
 Post Reply Post Reply Page  <1234>

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.06
Copyright ©2001-2023 Web Wiz Ltd.

This page was generated in 0.109 seconds.