aris Posted December 14, 2020 Share Posted December 14, 2020 Only the mid need chamfer not the woofer. I also did a slight chamfer of the BR ports as mine were a snug fit so chamfering helped get them in and also to hold a bead of hot glue. Overkill I think. For me it was the gluing that soaked up time reckon Thu will be a busy day for you! 1 Link to comment Share on other sites More sharing options...
Janus77 Posted December 14, 2020 Author Share Posted December 14, 2020 8 hours ago, aris said: Only the mid need chamfer not the woofer. I also did a slight chamfer of the BR ports as mine were a snug fit so chamfering helped get them in and also to hold a bead of hot glue. Overkill I think. For me it was the gluing that soaked up time reckon Thu will be a busy day for you! Thanks Aris, i was only talking about chamfering the woofer hole as i'm installing an additional support ring behind the woofer (bit like these http://www.troelsgravesen.dk/Faital-3WC-15_Hans-Kristian.htm), so wanted to ensure the air can flow freely. Chamfering the BR ports is good advice thanks, i noticed they are very snug on mine too. I need to level the fillets down with the baffle so the support ring can sit over them, wonder which tool will be best for that, use a facing machine, or will that just chew it up? Maybe a flexible hand saw is best, then sand it till flat. Link to comment Share on other sites More sharing options...
BioBrian Posted December 15, 2020 Share Posted December 15, 2020 I hope you have better luck cutting the vent pipe than my recent attempt. I'm putting this here for nobody in particular, but general warning... My vent pipes were 150 mm diameter, so a bit larger than in this build, but when trying to cut them with a Makita 10" cut-off saw, one piece suddenly leapt up in my face as the blade caught and twisted the pipe up - I'm lucky not to have lost a hand! After that I screwed a long piece of plywood to the saw's 'fence', stopping very close to the blade, so it had much more solid (and less slippery) support. Then I could turn it more safely. An end stop kept the length the same through the rotation, but it would have been great to have 2 people on board. Does anyone have a good method for cutting large PVC pipes square? Link to comment Share on other sites More sharing options...
Janus77 Posted December 15, 2020 Author Share Posted December 15, 2020 (edited) ouch. Good solution after you learnt your lesson though i reckon. Edited December 15, 2020 by Janus77 Link to comment Share on other sites More sharing options...
Janus77 Posted December 15, 2020 Author Share Posted December 15, 2020 3 Link to comment Share on other sites More sharing options...
PKay Posted December 15, 2020 Share Posted December 15, 2020 12 minutes ago, Janus77 said: Looking great - I think copper screws would finish off the look, and they supposedly improve SQ. 1 Link to comment Share on other sites More sharing options...
Janus77 Posted December 15, 2020 Author Share Posted December 15, 2020 (edited) They look darker when vertical too (ie. the scrapes aren't as visible in person when vertical). Ok ok, I rushed, i'm not stripping them back now though! And it's character, people love character, right? Not really noticeable from seated listening distance. How long does Poly need to dry so it's hard? I'm probably on coat 7 or 8, if i'm sanding them back tomorrow am i leaving enough time? It's so damn humid at present the curing process must be quite slow. Troels says he's working on The Loudspeaker 3! http://www.troelsgravesen.dk/Diy_Loudspeaker_Projects.htm#My_System Holy tolido Batman! Exciting times. Edited December 15, 2020 by Janus77 Link to comment Share on other sites More sharing options...
Janus77 Posted December 16, 2020 Author Share Posted December 16, 2020 Ok let’s do this! 1 Link to comment Share on other sites More sharing options...
BioBrian Posted December 16, 2020 Share Posted December 16, 2020 On 15/12/2020 at 8:41 PM, Janus77 said: Troels says he's working on The Loudspeaker 3! Well spotted. I felt something! Need a trip to the bank - to put my credit card in a safety deposit box. All the best for today. 1 Link to comment Share on other sites More sharing options...
Janus77 Posted December 16, 2020 Author Share Posted December 16, 2020 2 Link to comment Share on other sites More sharing options...
BioBrian Posted December 16, 2020 Share Posted December 16, 2020 The suspense is killing me! Link to comment Share on other sites More sharing options...
Janus77 Posted December 17, 2020 Author Share Posted December 17, 2020 1 Link to comment Share on other sites More sharing options...
Janus77 Posted December 17, 2020 Author Share Posted December 17, 2020 (edited) As is the norm, i was unable to complete my optimistic jobs list. However this time i accepted and refused to be rushed. I did however make quite a bit of progress. 1. support rings for woofers cut, sanded and installed. 2. A braces modified to go around woofer support rings (i still need to do some fine tuning on these) 3. Tweeter boxes constructed 4. binding post holes drilled 5. 1 box completely glued apart from front and rear baffle 6. 1 box glued to second stage (just needs opposing side, top and bottom glued in. 7. mid driver holes chamfered 45% 8. Grill frame lengths cut, 45 degree mitered ends, 45 degree inward facing side. 9. Port tubes cut. Brian i used the band saw with the parallel rip fence set, and just kept biting away at it turning the tube around until eventually they came apart. A good result. What took longer than expected? The glue up, first stage was painless apart from having to dry mount the top, bottom and opposing side to ensure the braces were straight. Second stage was ok too, third stage required quite a bit of prep. The rebates weren't quite deep enough so i had to use a small rebating plane which was a hell of a lot of fun, when you get the blade just right it's better than a hot knife through butter. Very satisfying hand planing wood! Also one of the braces was slightly off centre so i had to widen a rebate slightly. It's hard to express how much i'm enjoying the workshop, building these speakers has been quite a journey of learning and problem solving, highly engaging. Anyway the long and short i managed to get 1 box glued up as straight as I would have hoped for. with a rear baffle inserted to ensure they fit. The baffle has masking tape on it so any glue wont bond to the wood. I did scrape the poly off a small section of the front baffle when cutting the 2nd woofer hole. Polyurethane seems to need more than 1 day to cure properly. The test piece i made is rock hard now after several weeks. For the first few days it stays a little soft and should not be touched if it can be avoided. Anyway i'll sand it back and put a bunch more coats on, will be fine. Plan to sand the front baffles in a week or so after i've put another few coats on. Nearly out of polurethane varnish though. Edited December 17, 2020 by Janus77 6 Link to comment Share on other sites More sharing options...
PKay Posted December 17, 2020 Share Posted December 17, 2020 1 hour ago, Janus77 said: As is the norm, i was unable to complete my optimistic jobs list. However this time i accepted and refused to be rushed. I did however make quite a bit of progress. 1. support rings for woofers cut, sanded and installed. 2. A braces modified to go around woofer support rings (i still need to do some fine tuning on these) 3. Tweeter boxes constructed 4. binding post holes drilled 5. 1 box completely glued apart from front and rear baffle 6. 1 box glued to second stage (just needs opposing side, top and bottom glued in. 7. mid driver holes chamfered 45% 8. Grill frame lengths cut, 45 degree mitered ends, 45 degree inward facing side. 9. Port tubes cut. Brian i used the band saw with the parallel rip fence set, and just kept biting away at it turning the tube around until eventually they came apart. A good result. What took longer than expected? The glue up, first stage was painless apart from having to dry mount the top, bottom and opposing side to ensure the braces were straight. Second stage was ok too, third stage required quite a bit of prep. The rebates weren't quite deep enough so i had to use a small rebating plane which was a hell of a lot of fun, when you get the blade just right it's better than a hot knife through butter. Very satisfying hand planing wood! Also one of the braces was slightly off centre so i had to widen a rebate slightly. It's hard to express how much i'm enjoying the workshop, building these speakers has been quite a journey of learning and problem solving, highly engaging. Anyway the long and short i managed to get 1 box glued up as straight as I would have hoped for. with a rear baffle inserted to ensure they fit. The baffle has masking tape on it so any glue wont bond to the wood. I did scrape the poly off a small section of the front baffle when cutting the 2nd woofer hole. Polyurethane seems to need more than 1 day to cure properly. The test piece i made is rock hard now after several weeks. For the first few days it stays a little soft and should not be touched if it can be avoided. Anyway i'll sand it back and put a bunch more coats on, will be fine. Plan to sand the front baffles in a week or so after i've put another few coats on. Nearly out of polurethane varnish though. looks great. The humidity we are experiencing at the moment in Sydney is most likely slowing down your cure time on the lacquer. 1 Link to comment Share on other sites More sharing options...
Janus77 Posted December 17, 2020 Author Share Posted December 17, 2020 (edited) Will collect 1 box today and see if I can’t do a cheeky glue up of no.2 for collection tomorrow. Depends if the rebates need adjusting too. Staff Christmas party today for lunch. Workshop closes at 4. Troels released a new design today, http://www.troelsgravesen.dk/CNO-4.htm Edited December 17, 2020 by Janus77 Link to comment Share on other sites More sharing options...
Janus77 Posted December 18, 2020 Author Share Posted December 18, 2020 (edited) Still need to cut the bottom brace to accept the extra woofer support on the front baffle. I couldn’t be happier with the first box. Can’t believe I made this!! Edited December 18, 2020 by Janus77 3 1 Link to comment Share on other sites More sharing options...
Janus77 Posted December 18, 2020 Author Share Posted December 18, 2020 Box 2 glued. Solo glue up, bit stressful but it seems nice and straight. so turns out I do have 5 weeks access which means whilst yesterday was my last “class”, I still have a week to go, woohoo! 3 Link to comment Share on other sites More sharing options...
BioBrian Posted December 18, 2020 Share Posted December 18, 2020 That must be a relief. Well done! 21 hours ago, Janus77 said: It's hard to express how much i'm enjoying the workshop, building these speakers has been quite a journey of learning and problem solving, highly engaging. Thanks for sharing it with us. 2 Link to comment Share on other sites More sharing options...
Janus77 Posted December 18, 2020 Author Share Posted December 18, 2020 1 hour ago, BioBrian said: That must be a relief. Well done! Thanks for sharing it with us. I’ve received a lot of great advice from people on SN, I’m glad I shared or I’d probably have stuffed this build long ago! getting pretty close now people. Although I still have a pretty long list of jobs. I’m enjoying this enough to be glad of the list although I’m also very keen to plug them in and listen. 4 Link to comment Share on other sites More sharing options...
Janus77 Posted December 18, 2020 Author Share Posted December 18, 2020 (edited) And home we go. Need to give them a general sanding, clean up the corners, and cut out the other A brace for the woofer support. I have a jigsaw which will hopefully do the trick. Pity I only realised after first glue up that I needed to cut them, would have made it easier to cut them before they were installed. Will also paint PVA glue on all internal joins to ensure it’s sealed and strong. The grill frames, my instructor said maybe drill through each corner and glue dowel in to strengthen the joints. I need to do some strength testing on them first though to determine if they need a centre support strut too. back to Bunnings for another can of polyurethane when I have time. And some glue suitable for the port tubes. I might install the port tubes soon and do a few more coats of poly so I can sand back the inside and they present a flush surface. Edited December 19, 2020 by Janus77 3 Link to comment Share on other sites More sharing options...
Janus77 Posted December 19, 2020 Author Share Posted December 19, 2020 Does the job.. 1 Link to comment Share on other sites More sharing options...
Janus77 Posted December 19, 2020 Author Share Posted December 19, 2020 Who’s excited? Me! Link to comment Share on other sites More sharing options...
dcathro Posted December 19, 2020 Share Posted December 19, 2020 Sorry I missed this thread until now! Great work, I bet you are excited to get them up and running. Will follow with interest. 1 Link to comment Share on other sites More sharing options...
BioBrian Posted December 19, 2020 Share Posted December 19, 2020 Showing off some very nice joints there, Hugh. So glad you did the woofer rings. Lucky there was plenty of meat left on the front braces . Link to comment Share on other sites More sharing options...
Janus77 Posted December 19, 2020 Author Share Posted December 19, 2020 3 hours ago, BioBrian said: Showing off some very nice joints there, Hugh. So glad you did the woofer rings. Lucky there was plenty of meat left on the front braces . a sliver, but it was enough.. Link to comment Share on other sites More sharing options...
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