It is currently Fri Aug 18, 2017 3:55 am

All times are UTC-05:00




Post new topic  Reply to topic  [ 27 posts ]  Go to page Previous 1 2
Author Message
 Post subject: Re: Wedgehorn 8's
PostPosted: Mon Dec 12, 2016 7:12 am 
Offline
User avatar

Joined: Sat Aug 06, 2011 3:25 pm
Posts: 1020
Location: Manchester, UK
Chris_Allen wrote:
These cabs are looking great. How are you going to finish them?


Thanks Chris. I've pondered finishing quite a bit, after seeing others' ways of doing - the one that sticks in my mind was the polyurethane varnished horn insides. The main issue is really what would the expectations of others' be, if one is using them for potential hire (with me along for the ride of course)...? I think in that circumstance at least the outside needs to be standard black duratex, but maybe inside could be a different colour / finish. I do have some 'turbo blue' of the blue aran tuff cab and just might roll that all over inside and out - at least the driver, mesh screen & frame, and tweeters would contrast if they all stayed black. What could be nicer than all different types of finishes on different cabs.... So, I don't know. I'll take suggestions. I think it needs to be workman like finish and durable though.

_________________
2xJ12L (3012HO) switchable/melded (viewtopic.php?f=30&t=18773)
2xT30 : viewtopic.php?f=30&t=20386

No sound is better than bad sound.


Top
   
 Post subject: Re: Wedgehorn 8's
PostPosted: Sat Dec 31, 2016 4:44 pm 
Offline
User avatar

Joined: Sat Aug 06, 2011 3:25 pm
Posts: 1020
Location: Manchester, UK
I've fixed the horns in the shells and done a bit of rounding over, the latter being a new year's Eve treat. Well, it was either that, or doing my forex trading course tutorials.

Old lang zyne folks.


Attachments:
rps20161231_213609.jpg
rps20161231_213609.jpg [ 20.68 KiB | Viewed 3869 times ]
rps20161231_213800.jpg
rps20161231_213800.jpg [ 21.52 KiB | Viewed 3869 times ]
rps20161231_213654.jpg
rps20161231_213654.jpg [ 16.65 KiB | Viewed 3869 times ]
rps20161231_210841.jpg
rps20161231_210841.jpg [ 22.81 KiB | Viewed 3869 times ]

_________________
2xJ12L (3012HO) switchable/melded (viewtopic.php?f=30&t=18773)
2xT30 : viewtopic.php?f=30&t=20386

No sound is better than bad sound.
Top
   
 Post subject: Re: Wedgehorn 8's
PostPosted: Sun Jun 11, 2017 3:13 pm 
Offline
User avatar

Joined: Sat Aug 06, 2011 3:25 pm
Posts: 1020
Location: Manchester, UK
Sorry I've not been on this. Other things took over for 6 months, including a new job. However, some free time has come up, from the job - it's a long story and takes some explaining!

Anyway, I had some GRS piezos to test so I got the little double pole switch testing rig out I used a few years back and did 110 of them. It's a similar method to last time shown in the photo. The one thing that was clear was that the standard goldwood 1016 tweeter I had as the reference tweeter on the tester was too quiet to be able to distinguish the effect of switching the second test piezo in and out of phase - there was no addition or cancellation effect because the GRS was just swamping the goldwood by about 5 or 6 dB. So I swapped the goldwood for a GRS and it was good to go. The acoustic foam is to damp reflections that minimises the delta / difference between opposite phases and the SPL meter is cocked down near to the foam for the same reason. Out of 110 piezos, only one was the wrong polarity and 2 were low output.

I've always known the new budget saw bench I bought was not very square on the blade, and because I have some tweeter arrays to make I thought I'd have a serious look at making the cutting jigs referred in the panel jig plans. So, I got into the saw bench and reset the blade and motor support housing, by shimming with 4 thicknesses of coke can under one side of the interface and fasteners bolting it to its seating face ; so now it's much better than it was - it wouldn't cut anything of any length parallel against the fence before. So, on the budget bench the slots are not the standard 3/4" width, but they are 3/8" and I had some plywood to hand, so cut a few strips of that for the slots to make the panel jig. I'm not showing a photo of the panel jig - it is the standard version - however, my slight issue is that after getting it to slide as well as it would it was still quite stiff to push on the aluminium table bed. Maybe it is something to do with the coefficient of friction birch plywood and anodised aluminium, but I didn't feel like going on the make the piezo cutting jig and having to go to the effort of sliding a fairly chunky pair of jig backwards and forwards.

So, keeping the blade set low, I did what I've done before and got on with it, watching carefully what I was doing. Always satisfying gluing some arrays up.

Hope I can continue apace now with this.


Attachments:
File comment: Arrays
rps20170611_203230.jpg
rps20170611_203230.jpg [ 24.21 KiB | Viewed 338 times ]
File comment: 3/8" plywood strips
rps20170611_204126.jpg
rps20170611_204126.jpg [ 15.89 KiB | Viewed 338 times ]
File comment: Squaring the blade
rps20170611_163240.jpg
rps20170611_163240.jpg [ 15.18 KiB | Viewed 338 times ]
File comment: Testing piezos
rps20170611_161747.jpg
rps20170611_161747.jpg [ 25.44 KiB | Viewed 338 times ]

_________________
2xJ12L (3012HO) switchable/melded (viewtopic.php?f=30&t=18773)
2xT30 : viewtopic.php?f=30&t=20386

No sound is better than bad sound.
Top
   
 Post subject: Re: Wedgehorn 8's
PostPosted: Wed Jun 14, 2017 3:21 pm 
Offline
User avatar

Joined: Sat Aug 06, 2011 3:25 pm
Posts: 1020
Location: Manchester, UK
The cabs and front removable frames are ready for paint. Also made up the filters.

One thing I like about building these cabs is working out what order things need doing in. I know it's in the plans, but it's the details that I seem to end up thinking about. One of which was where I needed to put the NL4MPR sockets, and this seemed dependent on the size and location of where the filters would go, so I had to size the filter board and figure out where to fit them first. Etc., Etc. I also made a few drillings in the inside bracings using a right angled drill attachment so I can tie wrap wires from the piezo arrays as they come to the back of the cab.

This time, putting the filters together was quicker - when I made the J12L's I remember putting copper wire down on the board so they look like the schematics, but this time, I'm making maximum usage of the (flying?) wires on the ends of the components. It never occurred to me last time, but these wires are long enough to solder at multiple positions along the length. Do they look right? I put the filter boards on 1/2" ply legs at each corner and will glue the legs in, so there's a gap under the board for the tie wraps.

The mesh frames are made from some tanalised roofing batten I got for another job - lovely straight and close grained, no knots - cut to approx 3/4" thick and gusseted with 1" x 18mm thick birch. I'm looking forward to putting the pet screen mesh on the frames - planning to use some polyester thread to get it nice and tight in both planes then stick 3mm thick ply strips on the back of the frame to keep the tension before trimming. Excited to see how they turn out. The frame will stand out a bit I think - I probably could have made it to be flush, with a bit more sketching out, but it's not critical.


Attachments:
rps20170614_205016.jpg
rps20170614_205016.jpg [ 21.7 KiB | Viewed 297 times ]
rps20170614_205047.jpg
rps20170614_205047.jpg [ 21.92 KiB | Viewed 297 times ]

_________________
2xJ12L (3012HO) switchable/melded (viewtopic.php?f=30&t=18773)
2xT30 : viewtopic.php?f=30&t=20386

No sound is better than bad sound.
Top
   
 Post subject: Re: Wedgehorn 8's
PostPosted: Wed Jun 14, 2017 8:42 pm 
Offline

Joined: Tue May 09, 2017 5:37 pm
Posts: 51
Location: The Neterlands / Holland
You made some good progress! :clap: Painting is such a rewarding job to do (at least for me) and then you know the end is near. Keep up and you soon can be proud and happy you finally finished this project.


Top
   
 Post subject: Re: Wedgehorn 8's
PostPosted: Mon Jun 19, 2017 5:27 pm 
Offline
User avatar

Joined: Sat Aug 06, 2011 3:25 pm
Posts: 1020
Location: Manchester, UK
I did the painting: 2 coats in the horn and 3 externally, with the textured roller - I still had grain bleed with 2 coats but it won't be seen behind the mesh grill cloth. It's the best finish I've ever had on the external surfaces.

On to the corner protectors. Borrowed my brothers mitre saw. Finally figured out that it's not possible to do by holding the corner piece by hand up against the fence, but the actual cabinet corner needs recreating, with same router'd over radius, and corner pieces screwed on - they are not actually square (in cross section) until screwed on/down to where they will locate. A few photos of how I did it. The way I set the plastic corners on the wood jigs in the correct position (since each one is cut separately of course) is to cut a 6mm square return where the straight interfaces the radius corner of the plastic corner - the square return is lined up with the start of the radius. It does take a while though to do all the mitres for 2 cabs. I also put extra screw holes and countersunk them where the mitre offcut eliminated the existing fixing hole.

And the part I really wanted to get into - working out the tensioner for the mesh. My doorway carpet gripper rods came today in the post, so I could make a start. The pictures kind of show the idea. I realised I need to tension it in 2 directions but it's a bit much doing that in one go, and really, it's not a case of 'stretching' the pet mesh screen, more just getting it laying right over the frame - however, I did need a method of keeping the mesh on the gripper hooks. This was done by pushing overly long pieces of offcuts onto the spikes and jamming them against the extrusion profile return - with this method, each gripper spike could be done, one at once, and set in the mesh row and hole of choice. There's 3 sets of holes pairs in the gripper rods, each hole pair 1" apart and the pairs 6" apart. A sheet bend knot will be used to join the string loops and a Spanish windlass and dowel used to acquire the tension for each string loop. Will see how it goes tomorrow.


Attachments:
rps20170619_224456.jpg
rps20170619_224456.jpg [ 21.62 KiB | Viewed 254 times ]
rps20170619_224549.jpg
rps20170619_224549.jpg [ 23.35 KiB | Viewed 254 times ]
rps20170619_224619.jpg
rps20170619_224619.jpg [ 25.13 KiB | Viewed 254 times ]
rps20170619_224703.jpg
rps20170619_224703.jpg [ 25.44 KiB | Viewed 254 times ]
rps20170619_224736.jpg
rps20170619_224736.jpg [ 30.59 KiB | Viewed 254 times ]

_________________
2xJ12L (3012HO) switchable/melded (viewtopic.php?f=30&t=18773)
2xT30 : viewtopic.php?f=30&t=20386

No sound is better than bad sound.
Top
   
 Post subject: Re: Wedgehorn 8's
PostPosted: Wed Jun 21, 2017 4:06 pm 
Offline
User avatar

Joined: Sat Aug 06, 2011 3:25 pm
Posts: 1020
Location: Manchester, UK
I finished the last tensioning operation this morning on the mesh screens. It was possible to not put a retaining peg on every gripper rod spike - the spikes in between stayed engaged in the mesh, so this made it only a 10 minute job for each side, plus a bit for gluing and nailing the battens on.

Am pleased with the result. This one is the second screen - i realised courage is needed to properly trim the backside mitres at the corners and not try to overlap anything. The screen will stand out a bit yet with some velcro needing to go in the side joints, but I'll show a finished pic when done.

A photo of wiring the tweeters - I'm doing them series parallel with the grs piezos being more sensitive than goldwoods.

A photo of starting wiring in the filters. I'd forgotten how long this stage takes, well, me at least - it doesn't feel like I'm getting any quicker, :). I cannot manage to do it in the cab - the solution to me seems to make all the wires long enough to be able to join as much as practicable outside the back cover, on an elevated wooden board, then fit it all in and tie wrap wires off where you can. Is it ok to use hot glue for strain relief of (a) insulated wires interfacing the filter boards?, (b) to hold down flying lead wires on the board itself? I.e. do filters get warm enough to soften the glue - anyone had glue come undone. I know we tie wrap components down as well as hot glue, but I'm thinking that the interconnecting wires need to be tied down to stop resonant vibration from breaking anything - it will start to look way more of a dog's breakfast if I have to tie wrap them as well.


Attachments:
rps20170621_214530.jpg
rps20170621_214530.jpg [ 53.19 KiB | Viewed 214 times ]
rps20170621_214608.jpg
rps20170621_214608.jpg [ 68.9 KiB | Viewed 214 times ]
rps20170621_214705.jpg
rps20170621_214705.jpg [ 55.6 KiB | Viewed 214 times ]
rps20170621_214749.jpg
rps20170621_214749.jpg [ 42.22 KiB | Viewed 214 times ]

_________________
2xJ12L (3012HO) switchable/melded (viewtopic.php?f=30&t=18773)
2xT30 : viewtopic.php?f=30&t=20386

No sound is better than bad sound.
Top
   
 Post subject: Re: Wedgehorn 8's
PostPosted: Thu Jun 22, 2017 2:05 am 
Offline
User avatar

Joined: Wed Jul 11, 2007 2:43 pm
Posts: 3126
Location: Huddersfield, UK
Genius mesh tightening method.


Top
   
 Post subject: Re: Wedgehorn 8's
PostPosted: Sat Jun 24, 2017 7:21 am 
Offline
User avatar

Joined: Sat Aug 06, 2011 3:25 pm
Posts: 1020
Location: Manchester, UK
I thought installing the driver fixings might be a bit more straightforward with using torx headed screws, and a normal L-shaped allen key type drive, but it has still proved difficult. A hex headed screw would be even better probably, due to the distance between universal joint pivot and socket being shorter than with an extra screww driving bit in, but I haven't seen woodscrews with hex heads.

It has been a little easier using the universal joint driver and ratchet. I only had the 1/2" driver joint initially, but got the 1/4" and I think it may be a bit better - either way they need a bit of technique still, with their tendency to lock at certain angles of rotation.

I don't remember whether I drove the screws in after drilling the pilot holes so I've done it on the second cab to make it easier when the foam and driver is finally in there if the thread is already cut.


Attachments:
rps20170624_130246.jpg
rps20170624_130246.jpg [ 36.45 KiB | Viewed 174 times ]
rps20170624_130157.jpg
rps20170624_130157.jpg [ 47.72 KiB | Viewed 174 times ]
rps20170624_130055.jpg
rps20170624_130055.jpg [ 45.28 KiB | Viewed 174 times ]

_________________
2xJ12L (3012HO) switchable/melded (viewtopic.php?f=30&t=18773)
2xT30 : viewtopic.php?f=30&t=20386

No sound is better than bad sound.
Top
   
 Post subject: Re: Wedgehorn 8's
PostPosted: Mon Jun 26, 2017 10:46 am 
Offline

Joined: Tue May 09, 2017 5:37 pm
Posts: 51
Location: The Neterlands / Holland
Nice paintjob! Final bits and pieces and don't be to harsh on yourself otherwise the 80/20 rule kicks in and will the last 20% of work take 80% of the total project time. :roll:

Enjoy finishing them and listening!


Top
   
 Post subject: Re: Wedgehorn 8's
PostPosted: Mon Jun 26, 2017 3:39 pm 
Offline
User avatar

Joined: Sat Aug 06, 2011 3:25 pm
Posts: 1020
Location: Manchester, UK
Think wrote:
Nice paintjob! Final bits and pieces and don't be to harsh on yourself otherwise the 80/20 rule kicks in and will the last 20% of work take 80% of the total project time. :roll:

Enjoy finishing them and listening!


Thanks. Your self is the safest person to be hard on, when all said and done. The last person who was hard on me, other than myself, and apart from the kids, gave me garden leave and a month's notice, which I got paid for today - hooray - hence why I've had time to get back on it. ...But really, I'm counting my blessings.

I love the Pareto principle - too true.

_________________
2xJ12L (3012HO) switchable/melded (viewtopic.php?f=30&t=18773)
2xT30 : viewtopic.php?f=30&t=20386

No sound is better than bad sound.


Top
   
 Post subject: Re: Wedgehorn 8's
PostPosted: Fri Jun 30, 2017 9:42 am 
Offline
User avatar

Joined: Sat Aug 06, 2011 3:25 pm
Posts: 1020
Location: Manchester, UK
Well, I've finally got there.

Managed to find 3 to 4 dB difference for setting polarity of tweeters to woofer - don't know whether draped sheets would have helped, but I had to fish around in the air to find the peak with big polarity options - slowly moving the meter around.

The wood strip and then velcro depth build up is about 6 to 7mm, which because it's at 45 degrees pushes the mesh frame out about 8mm. I already set the horn back about 4 to 6 in the housing, so I reckon about an extra half inch of material on the cab side pieces (i.e. cut them bigger initially) is required to get the front of the mesh frames flush with the sides at the front, but it doesn't look too bad. The only thing required was to dress over the gap from the mesh to the 3mm wood strip with a smoothed out fillet of back sealant / adhesive. It's not neat and you can see it, but it doesn't detract too much.

I sprayed the tweeters the same grey as in my jacks, but it's not easy to see through the pet mesh screen.

The bottom photo is in our bedroom - the nicest carpet in the house. My wife said, "Oh Charles, it looks like we live in a hotel."

Thanks for reading.


Attachments:
rps20170630_152614.jpg
rps20170630_152614.jpg [ 66.69 KiB | Viewed 82 times ]
rps20170630_152644.jpg
rps20170630_152644.jpg [ 73.01 KiB | Viewed 82 times ]
rps20170630_152714.jpg
rps20170630_152714.jpg [ 50.45 KiB | Viewed 82 times ]
rps20170630_152758.jpg
rps20170630_152758.jpg [ 35.91 KiB | Viewed 82 times ]
rps20170630_152838.jpg
rps20170630_152838.jpg [ 43.35 KiB | Viewed 82 times ]

_________________
2xJ12L (3012HO) switchable/melded (viewtopic.php?f=30&t=18773)
2xT30 : viewtopic.php?f=30&t=20386

No sound is better than bad sound.
Top
   
Display posts from previous:  Sort by  
Post new topic  Reply to topic  [ 27 posts ]  Go to page Previous 1 2

All times are UTC-05:00


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
banner
Powered by phpBB® Forum Software © phpBB Limited