BioBrian Posted October 23, 2012 Share Posted October 23, 2012 Thanks again, Sierra. These are an inspiration. That really is a startling red, in the Jarrah. Have you found something good for the feet? I'm thinking mine might need little trollies incorporated into the design! They'll need to be solid, whatever, and knowing my floors, at least one will need to be adjustable. Can I ask what size hole you've used for the bushes? I thought of making a piece of steel, say 50x10mm flat, with a hole drilled with the vertical drill as a guide, so they could be screwed in straight, but haven't done any tests yet. As I said previously, I haven't found the right sized hole yet, but also wondered about drilling oversize, and gluing them in with 5-min epoxy. As long as the glue doesn't come up the centre hole... Which drivers are getting the bush treatment - I take it the waveguides didn't? Had some fun today with my copy of Troels' circle-cutting router jig. It was surprisingly stable, and stayed in place when swapping hands. So good when something goes right. Cheers, B. Link to comment Share on other sites More sharing options...
Sierra Posted October 23, 2012 Author Share Posted October 23, 2012 Thanks for your kind word's Brian ... Yes the deep red of the Jarrah really is a great contrast to Tasmanian Oak ... and the contrast between the two will "pop" even more once they are laqured. Hmmm ... the feet ... this is the one thing that has given me a headache ever since the beginning. I'm not a fan of the feet that Troel's has used as the mounting seems very "flimsy" to me. These are not light speakers (and yours even heavier) and I worry that there is a chance of dislodging the feet should they snag on something while being moved/positioned. I have thought about using "outrigger" type feet /spikes or fabricating a frame that would bolt to the underneath of the speaker and welding feet onto it so that the load would be transfered from the metal frame to the speaker rather than from just an individual foot. I'm still working this one out and I think I'll be firing the speakers up with them sitting on packers temporarily till I come up with a solution. I don't know what size the bush holes are ... Brian (the cabinet maker) just started drilling and screwing ... Once I get the finished cabinets home I can measure them and tell you. I like your idea of a "screwing in jig" to keep the bushes straight. I still need to screw in all the bushes for the Deltalite drivers in thwe back so I'll see how I go ... and yes I had similar thoughts about epoxying them in as well depending on how tight a fit they are. No big deal if the epoxy gets onto the hole ... just run a small drill carefully through and run a tap through it. All drivers are getting the bushes ... including the waveguides. Great to hear you had success today with the circle cutting after the recent frustrations you've had. Link to comment Share on other sites More sharing options...
Dustin Posted October 23, 2012 Share Posted October 23, 2012 Hey Brian, If you're using Helicoils, did you purchase the whole kit or just the inserts? A "Recoil kit" will include the inserts as well as a special tap to suit the OD of the inserts and a hand tool to wind them in. Having used this system many times in metal, it should be a doddle with timber. Looks like this: http://www.ebay.co.u...0-/110949552562 Sierra, Those cabs look very neat and will be brilliant with the clear coat. Link to comment Share on other sites More sharing options...
BioBrian Posted October 23, 2012 Share Posted October 23, 2012 Hi Dustin, thanks for your exchange. I might have used the word "helicoil" in the wrong way. The Janzen bushes and 5mm bolts come together, but that's it: no instructions or tools. The OD of the bush is about 10mm, so quite a thick wall, not like the 'thread repair' metal-work ones. You screw it in with a large (10mm) screwdriver, and being only about 14mm long, and very tapered on the end, it'll just grab with the first bit of thread to find a ply or something, and take you for a ride. I thought if you drilled the right sized hole it would find sympathy with my intentions, but no. The baffles are 41mm thick, the recess 8mm, and the bush hole 15?, which should leave 16mm intact, so air can't get past them. So using a tap to clean out might mean drilling right through and spoiling one advantage of the system. I have to rout the waveguides today for the JA8008 mids, so will have a play on some scrap. Sierra, I had the same idea about welding up a base plate. This would protect the soft edges, and look really solid in black, and could have indestructible feet. It is a real issue moving these around, even to get from workshop to house is fraught. This is another concern for me, regarding those binder posts, which are rather vulnerable to a 200?kg beast rolling around on them. I suppose for transport they'd have to be on their sides, but I do feel like putting some wooden knobs on the 4 corners of the back just to protect the woofers, if they have to be laid out for surgery or whatever. On another note: when I was rebuilding my Vifa 3-ways recently, I drove them up to the workshop on their backs, and when I got there one of the 3" dome mids had disappeared into its internal enclosure. The 30YO glue had just cracked and the driver departed from its waveguide, so I'll try to transport speakers on their sides from now. (Anyone know where to source Vifa D75MX, or their Scanspeak replacement? I've replaced the woofers with SEAS, and the tweeters with Scanspeak, and one D75 is distorting, so I reckon their time is up, especially after my repair!). Sorry to bend the thread. Link to comment Share on other sites More sharing options...
Dustin Posted October 24, 2012 Share Posted October 24, 2012 Hi Brian, Got a pic of the screw inserts? You might try screwing a bolt into the insert, positioning the insert over the hole and giving it a moderate tap with a hammer. The idea is to get the insert started in the hole and from there it should screw in properly. A bit like this: Link to comment Share on other sites More sharing options...
BioBrian Posted October 25, 2012 Share Posted October 25, 2012 Thanks, Dustin. Your inserts look the same as mine, except mine don't have a lead-in: the ends are really fat, with the thread going right to the not-pointy end. Bit like the bow of the Lady Nelson, compared with a modern Sydney-Hobart maxi. I wish I'd read your idea a day earlier, as I think it would have been great, even better in combination with mine! I used the jig idea, and now have all the waveguide and mid-woofer holes bushed. About 3 of 20 needed remedial action (drilling- or filing out and glue), which was a pain, but hopefully will work when it all goes together. Sorry, but I've looked all over the website, but can't find how to post pics. Can anyone help me please? Link to comment Share on other sites More sharing options...
Sub Sonic Posted October 26, 2012 Share Posted October 26, 2012 When you reply, click on the "More Reply Options" box down on the lower RH corner of the text box. Then click on the "attach files" box underneath, find your picture when the extra window opens, double click on it and then press "add to text" (or something like that) when you want to add it. It's actually simpler than it sounds... Hope this helps! SS Link to comment Share on other sites More sharing options...
Sierra Posted October 26, 2012 Author Share Posted October 26, 2012 @ Dustin - I can't wait to see the cabinets when they are finished clear coating ... only a couple of weeks to go Because the speakers will be standing on carpet I've given myself an option and had some Jarrah bases made up with bevelled edges and these are also getting clear coated. So this will give me two options ... have the Jarrah bases with spikes that go through the carpet onto the concrete slab and the speakers stand on the bases ... or have spikes on the speakers and have them go through the carpet directly. I like your idea of locking the bolt to the bush and then using that as an assembly to screw the bush in ... that will make it much easier to control the bush rather than struggling with just a screwdriver. @ Brian - Your build is going to give you some challenges with it's sheer size. I think welding up a base plate would definately be the go in your situation it would make the most solid base for your feet arrangement. Regarding your binding posts concerns you could always leave them to the very last when you have moved the speakers to your listening room ... you'd only have to do a bit of soldering at worst for the final connection Great to hear that your jig for the bush's worked and that you got almost all of them fitted without remedial work. Should you ever need to run a tap down the thread you can get what is called a "plug" tap which has no lead in taper and allows you to run a thread right to the bottom of a hole that doesnt go all the way through the material. I imagine you have the same bush's as mine ... @Sub Sonic - Thank you for helping Brian out with attaching pictures Link to comment Share on other sites More sharing options...
BioBrian Posted October 26, 2012 Share Posted October 26, 2012 Thanks, SS. I'll try with 2 pics. I've already had a try, but couldn't get text and pic to show in order. Here goes again... My jig for inserting bushes straight when they feel like it: The 2nd one shows the myrtle next to the Baltic Birch ply. Gave both of these an initial coat of water-based sealer, which is why I dared to put the screwdriver down there! Still looking at options for the baffle edges: would like to use Tas timber, something pale and durable to cope with those inevitable knocks. Link to comment Share on other sites More sharing options...
BioBrian Posted October 26, 2012 Share Posted October 26, 2012 Well the 2nd one didn't come to the party. This time? I think I get it. Either wait ages for it to upload, or downsize pic before trying... What fun. Now can I go and finish these speakers? Link to comment Share on other sites More sharing options...
Sierra Posted October 27, 2012 Author Share Posted October 27, 2012 Nice work with the jig Brian looks to have made the installation much easier. With your baffle edges how about using what I did ... Tas Oak which is pale and hopefully not too soft ... I guess I will find that out myself in due course Looks like you've got a complex edge to create with the multiple angles as per the drawing :o When uploading pictures ... I resize mine to 1600 x 1200 first which makes for a friendly compromise between file size and resolution detail and doesn't take long to upload. Link to comment Share on other sites More sharing options...
Dustin Posted October 29, 2012 Share Posted October 29, 2012 I like your idea of locking the bolt to the bush and then using that as an assembly to screw the bush in ... that will make it much easier to control the bush rather than struggling with just a screwdriver. I imagine you have the same bush's as mine ... Hey Sierra, Are those 4mm ID threaded bushes? Perhaps word of caution. Remember that MDF is notorious for splitting with threaded fasteners and those bushes have a very course and deep external thread. Jarrah isn't exactly a soft timber either and the receiving holes are going to be close to an edge. I'd expect that type of bush is more intended for ply or softer timbers but ensuring the holes aren't too tight should help. Personally, I'd probably grind off most of that external thread and glue them in with a 24 hour epoxy. It's not like your bolting a solid rocket booster to the side of the space shuttle. Link to comment Share on other sites More sharing options...
Sierra Posted October 30, 2012 Author Share Posted October 30, 2012 Hey Dustin ... Yes they are 4mm internal threaded bushes ... they have already been screwed into the front baffles so no problems there. While the holes are already drilled in the MDF rear baffles ... I will do a couple of tests on some scrap MDF to make sure the existing holes are not too tight a fit around the external thread of the bush to cause problems. Link to comment Share on other sites More sharing options...
Dustin Posted October 30, 2012 Share Posted October 30, 2012 Onya Sierra, Well done . . . no problem then. You have me thinking with your jarrah base idea because I haven't really found a 'nice' idea for legs. Oh, I may have accidentally ordered some DeltaLites . . Link to comment Share on other sites More sharing options...
Sierra Posted October 31, 2012 Author Share Posted October 31, 2012 So ... accidentally ordered some Deltalites eh ... I'm still at a loss of how I will configure the legs ... do I have straight legs (stainless steel tubes perhaps) sitting ontop the Jarrah bases ... or do I go for spiked legs onto the Jarrah bases or do I omit the bases all together and just go straight onto the carpet with either option? Decisions decisions ... At this rate I can see myself sitting the cabinets on a pair of 45 x 90 pine battons while running them in until I've decided on the final leg configuration At the moment I don't have any pictures of the bases as they were a last minute thought just before the cabinets went off to the polishers ... so pics will have to wait until I get everything back. Link to comment Share on other sites More sharing options...
BioBrian Posted October 31, 2012 Share Posted October 31, 2012 Sierra, it sounds like you'll need spikes under the Jarrah bases anyway, if on carpet. It's actually one of my next questions for Troels: any different treatments, or air gap width, for wood or carpet floors? Surely they will sound better on wood! You could cut 4 pieces of say 40mm RHS (square steel tube), sit them vertically on the bases, and bolt (coach screws?) through the lot into your speakers. They could be painted whatever colour, positioned whenever (eg distance from edges - a dob of glue when you decide), and would be a solid acoustic and mechanical connection with the bolts under tension, compressing all. Matt black could look quite smart in contrast to the wood. While 40mm might seem over-engineered, the aesthetics are the most important consideration. When I built my subwoofer with its external vent, I made a frame and legs, using 40mm RHS to support the box, which is about a 500mm cube. While the frame is very stiff and strong, it made whole thing look a bit spindly and anorexic, so next time I'd go for the solid look of 50mm. If you go for SS tube, it could be seated in the base just by drilling a little hole for neatness, but I'd still suggest a large size, like 40 to 50mm, to acknowledge the weight and gravitas of your project! Might need a triangular piece of flat welded to the top, to locate & screw into the thin horn ends. Dustin and Sierra: the bushes I used were 5mm (actally more like 4.6, but I presume that's normal metric size). Maybe that's why they were so cantankerous. I bought both sizes, and found the 5mm a perfect fit for the waveguides and JA8008s, so no tolerance for error. Think I'll stick with the 14ga self-tappers for the Deltalites though. They have a very neat fit, and can't really go in crooked, unless the holes are in the wrong place. Anyone want 40 x 4mm bolts & bushes? They cost me 12 Euro plus freight, but I don't need them... Link to comment Share on other sites More sharing options...
Sierra Posted November 1, 2012 Author Share Posted November 1, 2012 Hey Brian ... Spikes under the Jarrah bases are a given I had already asked Troels the question about having the speakers directly on carpet and if it impacted adversly on the horn ... this was his reply ... "No problem with carpets. With a ~30 mm distance to the floor the covering has no impact on performance except for what carpets generally does to room acoustics." I'm having trouble picturing what you're describing with the coach bolts connecting the RHS to the speakers ... as there is nothing to bolt through ... Anyway ... 40mm RHS legs could definately be an option ... welded to a metal frame that will be bolted to the base of the speaker via more of those 4mm bushes. A satin black finish would definately work well for sure. I also bought both size bushes 4mm & 5mm ... but I opted for using the 4mm ones for the opposite reason you did. The 5mm bolts were just as you say "no tolerence for error" as they were almost size for size with the wave guide holes ... so I went for the smaller ones to allow myself for a slight tolerence error in the positioning Damn ... if only you had told me a month ago you had a bag of 4mm bushes you didn't need ... as I had to buy a secong bag from Jantzen because I needed more. I have a bag of 5mm if you need them ... LOL If you want solid speakers stands you'd be hard pressed to find anything more solid than the stands I use on my current speakers. The spiked base is 25mm thick mild steel ... the centre post is 90mm heavy wall RHS filled with lead shot ... the plinth is 50mm thick mild steel. These things are seriously HEAVY!!! Link to comment Share on other sites More sharing options...
BioBrian Posted November 2, 2012 Share Posted November 2, 2012 Yeah sorry, it wasn't very helpful. I thought one could get away with 4 tapered wooden (45deg angle) blocks in the corners, for bolting into, at least in the front. One thing is that all the angles inside the tube are "right", so it'd be possible to glue/screw some mild steel "angle" (say 50x50x6) inside each corner, and have your RHS feet welded to that - the placement might actually look just right, wall-thickness inside of the outside corners. This would preserve the gesture of wood - space - wood, without the intrusion of horizontal plates needed if screwing up into the thin walls. I haven't been able to come up with a solid-looking steel frame that wouldn't hinder the precious air shape inside the tube, or add to its length. Then there's the possibility of vibration if anything comes loose between the different materials. Not sure why you're so keen to use those bushes and bolts for such a HD task - you must like them by now! I'd be going for something with a bit of length and diameter. (No, not 5mm bushes!) JFTR, my bushes were actually 14 Euro (plus freight and money conversion), so not the happiest purchase I've ever made! But better currency than money, the way the banks rob us so much with international transfers. And WOW! Your old speakers would make the most musical outdoor umbrella stands ever! I need something like that for my turntable... I appreciate the discussion Sierra, forgive my thinking aloud like the above, but it's SO helpful, knowing there are people out there with such similar interests/passions. Link to comment Share on other sites More sharing options...
Sierra Posted November 3, 2012 Author Share Posted November 3, 2012 Yeah sorry, it wasn't very helpful. I thought one could get away with 4 tapered wooden (45deg angle) blocks in the corners, for bolting into, at least in the front. Ah …. I think I can picture what you were getting at now … One thing is that all the angles inside the tube are "right", so it'd be possible to glue/screw some mild steel "angle" (say 50x50x6) inside each corner, and have your RHS feet welded to that - the placement might actually look just right, wall-thickness inside of the outside corners. This would preserve the gesture of wood - space - wood, without the intrusion of horizontal plates needed if screwing up into the thin walls. Now that’s heavy duty! I haven't been able to come up with a solid-looking steel frame that wouldn't hinder the precious air shape inside the tube, or add to its length. Then there's the possibility of vibration if anything comes loose between the different materials. Hmmmm … I'm guessing if airflow toward the opening of the horn would be critical then Troels probably wouldn’t have mounted those huge crossovers in that area. Not sure why you're so keen to use those bushes and bolts for such a HD task - you must like them by now! I'd be going for something with a bit of length and diameter. (No, not 5mm bushes!) Actually I don’t believe it’s as heavy duty a task as you might think. Don’t forget that all of the weight of the speaker will be bearing down on the leg/support frame (for want of a better name) itself and not on the bolts & bushes directly ... so in normal use they do virtually nothing. The bolts will only be supporting the frame if the speaker is lifted or moved around etc. On the other hand for your speakers that are 50% taller than mine (and obviously heavier) stability would be an important factor … perhaps outrigger spikes/feet might be a better option giving you a wider footptint and more stabilty should anyone lean against it or something like that. JFTR, my bushes were actually 14 Euro (plus freight and money conversion), so not the happiest purchase I've ever made! But better currency than money, the way the banks rob us so much with international transfers. Mine was 29 Euro plus freight … but also bought the binding posts, the dayton terminal plates and a couple of other bits & pieces. And WOW! Your old speakers would make the most musical outdoor umbrella stands ever! I need something like that for my turntable... They would make a very sturdy turntable support/base I appreciate the discussion Sierra, forgive my thinking aloud like the above, but it's SO helpful, knowing there are people out there with such similar interests/passions. It’s all good fun Brian … kicking idea’s around and sharing thoughts Link to comment Share on other sites More sharing options...
Tube Nube Posted November 8, 2012 Share Posted November 8, 2012 Hi Alan, Those speaker cabs look great! How are you managing the anticipation? It must be sooo very close to ready. Brenton Link to comment Share on other sites More sharing options...
Sierra Posted November 9, 2012 Author Share Posted November 9, 2012 Thanks Brenton ... Great to see you here I just need to be patient ... a couple more weeks and I'll have the cabinets at home. Then my biggest problem will be to make sure I don't scratch them while I fit them out. They'll make a nice Christmas present to myself Link to comment Share on other sites More sharing options...
Tube Nube Posted November 11, 2012 Share Posted November 11, 2012 And what a lovely pair to treat yourself to for Christmas! I wonder if your cabinet making / polishing friends will soon be asked to do more speaker projects? Your pix aren't doing them any harm! Link to comment Share on other sites More sharing options...
Sierra Posted November 17, 2012 Author Share Posted November 17, 2012 Very true Brenton ... Brian is flat out with work at the moment ... although another mutual friend of ours is planning a little job for him early next year. I'm hoping to hear something about the cabinets next week ... shouldn't be too far away. I have been trying to decide for a while now on how to do the feet for these speakers as I don't like the ones that Troel's used on his prototype. I've been loooking at different options between spikes and feet and outriggers and had not been able to find what I had pictured in my mind ... until a fellow SNA'er posted a link in another thread that led me to a set of spikes that should work out with what I had in mind. This is the feet that Troel's used This is the spike that will suit what I had in mind ... it's also the correct length for the gap that has to be kept between the floor and the bottom of the speaker. I wont be using the T-Nut ... instead I will fabricate a metal frame that gets bolted to the bottom of the cabinet and I'll weld nuts to the frame for the spikes to screw into instead. This will create a much more solid mounting than just individual T-Nuts attaching into mdf. The spikes come in either gold or black chrome ... and they both look good ... Hmmm ... another decision to make Link to comment Share on other sites More sharing options...
BioBrian Posted November 17, 2012 Share Posted November 17, 2012 Looks pretty smart, Sierra. Would those horizontal lines, two-thirds down, mean you can remove the sharp spike ends, and have a small circular base for hard floors? I wonder how you'd go moving, or even placing them, if you have firstly spikes on your plinths, then spikes on the speakers. Are you doing away with the jarrah plinth idea? I thought if you kept the plinths, you could just use a spade bit to make small recesses in the cab bases and plinth (need to build out the front corners with a 'quad'), and place your original (31 Oct) SS tubes between, and bolt up from below the plinth, so they would always be in alignment, and you could just 'walk' the speakers around on the plinth spikes. Another thought was drilling and tapping into the metal frame, if you go that way, doing away with welding nuts, so the spikes could sit directly on the frame. Just trying to be helpful; I'm going through the same stuff myself. Feel like I've hit a wall, with the baffle edges and feet being the final hurdles. Troels reiterated via email that 25-40mm is the ideal gap underneath. I'm still working on using 50mm RHS feet, without spikes, as after trying to move these monsters around, I worry about the PSI under spikes! (Might be useful in the mining industry?). One idea is to weld a nylex nut inside the bottom of a couple of the feet and use (rounded) bolts up into it, to give some adjustment on uneven floors. Looking forward to hearing of your outcomes... Link to comment Share on other sites More sharing options...
Sierra Posted November 18, 2012 Author Share Posted November 18, 2012 Hey Bio_Brian ... Good question about those horizontal lines ... I would assume they are purely decorative but if they actually do come apart and have a flat surface then bonus ... more options ... LOL I have thought about the spikes in the plinths and then spikes on the speakers and the possible awkwardness of moving them around with this combination. The plinths would need to be put into the correct position first and then the speakers put on top. I'm banking on not having to move them around too much ... to start off I'll be positioning them in the same locations as my current speakers so with a bit of luck that's where they will stay. The thought certainly had crossed my mind of "fixing" the plinth to the base of the speakers at a set distance but I had sort of dismissed it ... until now ... you've "rekindled" the idea ... damn it!! If I was to do it I wouldn't be using SS tubing for that job ... I'd use solid bar instead. And would probably use mild steel bar as it's easier to work with and "finish" ... either paint or chrome or other ... As far as the frame goes my thought was to fabricate it out of 3mm thick flat bar and then weld a nut to give the extra thread depth by tapping the thread through the flat bar and continuing into the thread of the nut. To tap a thread directly into the frame doing away with the welded nut would mean a minimum thikness of 6mm which may make the frame more obvious. I would rather the frame not be seen unless you happen to be at eye level on the floor with it. Until I get the cabinets back and start to measure things up and see how things look I'm not going to make any hard and fast decisions ... so any of these combinations are possible ... Thanks so much for your sketch ... nice work ... and now I know what you mean when you describe your RHS feet with adjustable nuts ... a picture certainly is worth a thousand words Spikes on monsters like yours would make it really hard to move around for sure. Maybe you could use some of those "EZ Moves" pads you see on Global Shop Direct to slide your speakers around on till you find the spot you want and then remove the pads Which ever feet option we both decide on it has to be adjustable to make up for uneven floors and our own fabrication tolerances. So your cabinets are complete and you are now working on the complicated baffle edge chamfering? Link to comment Share on other sites More sharing options...
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