bertbass Posted July 8, 2016 Share Posted July 8, 2016 I’ve wanted to make a super light cabinet for quite a while now and as soon as I found that Bill Fitzmaurice, known and respected by all here on Basschat, had designed the Jack 12 Lite I bought the plans intending to give it a go but why not make it incredibly easy to build as well. Having a laser cutter, I decided to cut out all the parts in advance, in effect making a Jack 12 Lite kit. Having built a few of Bill's design in the past, OT12s, T39s, Jack 15s Jack 1s2 and Wedgehorn 6s, I already know how good Bill designs are. I set to work transferring all the parts needed into a cad program, loaded them into the laser cutter and cut them out from ¼ ply. While the plans were in the cad program I added tabs so that all the parts just slotted together. I’m quite confident that I got all the tabs in the right place but only by making the cab will I know for sure. The only tools I intend to use are a staple gun, Stanley knife, a phillips screwdriver and a sharp chisel, ( the chisel is used mostly to remove excess glue ). The hammer is in the photo because everyone has to have a hammer and it might come in handy. Polyurethane Adhesive and a mastic gun. PL construction adhesive is used in the States but is next to impossible to find in the UK but a quick visit to Screwfix will get you fixed up. As long as it's gap filling you're good to go. A can of Tough Cab paint. Useful as a weight as well. For a bench I've used an old school desk. Here’s 3 photos. The 1[sup]st[/sup] is the bench and tools. The 2[sup]nd[/sup] is the sheets of ply ready to cut and the 3[sup]rd[/sup] is of the parts cut out and ready to assemble. Construction starts tomorrow. Quote Link to comment Share on other sites More sharing options...
gary mac Posted July 8, 2016 Share Posted July 8, 2016 Come on then, get on with it I'm looking forward to seeing this one take shape. Quote Link to comment Share on other sites More sharing options...
3below Posted July 8, 2016 Share Posted July 8, 2016 (edited) Really like the idea of laser cutting the panels I will be interested to know how you get on with PU adhesive and the staple gun. My attempt looked good but I found the joints lacked strength. I resorted to tacking with staple gun followed by clamping whilst glue set. Did you ever 'dispose' of the unloaded J15s? Edited July 8, 2016 by 3below Quote Link to comment Share on other sites More sharing options...
bertbass Posted July 8, 2016 Author Share Posted July 8, 2016 J15s gone I'm afraid. They ended up on the bonfire due to total lack of interest from anyone. Starting to build tomorrow, not too early though. Watch this space!!! Quote Link to comment Share on other sites More sharing options...
Beer of the Bass Posted July 9, 2016 Share Posted July 9, 2016 1/4" plywood? That's certainly going to be light, though I'm quite curious to see how the bracing is done when using such thin ply. Quote Link to comment Share on other sites More sharing options...
bertbass Posted July 9, 2016 Author Share Posted July 9, 2016 (edited) Started assembling my Jack today by installing the horn braces to the sides. If you've got the plans you'll see that I've modified them to make assembly easier. [attachment=223097:SIDES & HORN BRACES.jpg] Using my amazing horn brace brace and the can of of tough cab as a weight all went well. all the braces fitted in the tabs perfectly and are all square and vertical. Plenty of glue squeeze out too, but that's what the chisels for. [attachment=223096:HORN BRACES GLUED.jpg] [attachment=223095:HORN BRACES FITTED.jpg] The glue has dried so I might as well fit the baffle, top and bottom. This is so easy! All the tabs line up and everything just slots into place. perfectly square too. I used 3/8" staples to hold the sides to the top and bottom, i would have preferred 1/2" staples but my son seems to have used them all and I didn't want to stop head off the Screwfix for some more. The 3/8" staples worked great though, holding everything together until the glue sets. Inserted the baffle before fixing the top and with the top stapled I laid the cab on its front and again used the can of tough cab as a weight on the baffle to get a good, tight fit to the horn braces. [attachment=223099:CAB ASSEMBLED.jpg] As it stands I can easily lift the assembled parts with my little finger. I'm liking this a lot. Edited July 9, 2016 by bertbass Quote Link to comment Share on other sites More sharing options...
Gottastopbuyinggear Posted July 9, 2016 Share Posted July 9, 2016 Blimey, this is making my Basschat 1x12 build approach look pretty agricultural! Ageing Bosch jigsaw failed half way through the rough cut for the speaker today, so I need a new cutting device. How much would a laser cutter capable of cutting 3/4" ply set me back? A little more than a jigsaw I suspect... I'm very impressed, and a little envious... Quote Link to comment Share on other sites More sharing options...
bertbass Posted July 9, 2016 Author Share Posted July 9, 2016 Bummer. I suspect that a new jig saw might be a little bit cheaper, probably by about £6000. Nothing wrong with your build though. It's looking good. Quote Link to comment Share on other sites More sharing options...
Gottastopbuyinggear Posted July 9, 2016 Share Posted July 9, 2016 I'm on the second cab, which I don't really need, so it's not a huge problem. Looking forward to hearing more on yours though. Quote Link to comment Share on other sites More sharing options...
bertbass Posted July 9, 2016 Author Share Posted July 9, 2016 Thanks. Watch this space for the next thrilling episode. Quote Link to comment Share on other sites More sharing options...
3below Posted July 9, 2016 Share Posted July 9, 2016 Should be finished by Sunday afternoon at this rate Quote Link to comment Share on other sites More sharing options...
bertbass Posted July 9, 2016 Author Share Posted July 9, 2016 Not Sunday, Most of tomorrow is set aside for being Grandad. Quote Link to comment Share on other sites More sharing options...
discreet Posted July 10, 2016 Share Posted July 10, 2016 This is great, Tel! I'd be really interested to know what the finished weight is with a driver in it. Quote Link to comment Share on other sites More sharing options...
Muzz Posted July 10, 2016 Share Posted July 10, 2016 This looks great, can't wait to see how it turns out. It looks so light it might even start a Best Lightweight Paint? thread... Quote Link to comment Share on other sites More sharing options...
bertbass Posted July 11, 2016 Author Share Posted July 11, 2016 Managed to do a bit yesterday after all with my 4 year old grandson, Tom, giving me a hand. Time to fit the horn sheaths. I've used flexiply for the sheaths and cut it to size on the laser cutter. I had the power too high on the first one and it's left a bit of soot on the edges, not a problem though and power lowered for the rest which has worked a treat. I'm not sure that I really trust the glue to make a good seal on 1/8" ply on a butt joint so I've added a few extra strips of ply just to be sure. [attachment=223249:READY FOR HORN SLEEVES.jpg] Marked out where the horn braces are and where the sides end and glued and stapled together. Using flexiply made it so easy. Just push down with one hand and staple with the other. [attachment=223250:HORN FITTED.jpg] Now the glue has dried I used the Stanley knife and a straight edge to trim the horn sheaths to size. 3 cuts and it was through. I forgot to add glass paper to the list of tools required for the build. Sanded the horn sheaths flush with the sides and I'm ready for the next part of the assembly, the ducts. Once glued in place, the flexiply is as rigid as non-flexiply. It's solid! The staples worked really well on the top, bottom and sides holding everything tight until the glue dried. [attachment=223251:HORN CUT TO SIZE.jpg] More later. P.S. I've used smaller, black & white photos to save on disk space. Quote Link to comment Share on other sites More sharing options...
discreet Posted July 11, 2016 Share Posted July 11, 2016 Great work mate, looks super-neat. Quote Link to comment Share on other sites More sharing options...
bertbass Posted July 11, 2016 Author Share Posted July 11, 2016 Why thank you sir. Probably post again later today, just waiting for some more glue to dry. Quote Link to comment Share on other sites More sharing options...
Bigwan Posted July 11, 2016 Share Posted July 11, 2016 This looks like one of those projects Glowforge would have on their webshop! Awesome work! What laser cutter do you have, by the way? Been tempted by one of the cheapo chinese 30w ones as I enjoy tinkering... Quote Link to comment Share on other sites More sharing options...
bertbass Posted July 11, 2016 Author Share Posted July 11, 2016 Many thanks. I've got one of these. https://www.youtube.com/watch?v=gLzZRGvu85Y Dual tube, 100w and a 60w. Quote Link to comment Share on other sites More sharing options...
3below Posted July 11, 2016 Share Posted July 11, 2016 I thought I had dome well getting industrial bandsaw, table saw and various other bits of kit past swmbo. Laser cutter of this size will present a challenge Having no experience in this field, how long did the actual panel cutting take in total? Quote Link to comment Share on other sites More sharing options...
bertbass Posted July 11, 2016 Author Share Posted July 11, 2016 (edited) It didn't take that long to actually cut out. It could be worked out as it was cutting at 20mm / second but then I engraved the part names on each bit as well. I would guess that it took 2 to 3 hours in total. Mind you, it took quite a few days to get the plans converted into DXF files for the laser cutter. I was however working in and around other cutting and engraving jobs. I've also got a well equipped workshop. Band saw, table saw, thicknesser planer etc. and I've used them extensively on other builds but the idea behind this project is to make a cabinet kit that can be made with the minimum of tools and no experience and also to be super light but still sound fantastic. Edited July 11, 2016 by bertbass Quote Link to comment Share on other sites More sharing options...
3below Posted July 11, 2016 Share Posted July 11, 2016 20 mm/s is a pretty impressive cutting rate. Apart from the upfront capital costs I can see many advantages of laser cut for sheet work, not least no dust (other than initial down size from 8 x 4), no blade sharpening, much less edge fettling etc. Any thoughts of selling flat pack BFMs? Quote Link to comment Share on other sites More sharing options...
bertbass Posted July 11, 2016 Author Share Posted July 11, 2016 (edited) Just back from the workshop / shed / man cave, so on with the build report. This afternoon I installed the duct braces, ducts, throat sheath braces, the throat sheaths and the phase plug dome. I've also fitted the top hats as I also want to use them for P.A. First to be fitted are the duct braces. These are glued and slid into their slots rapidly followed but the ducts. Also glued and slid into place. The hammer makes a great weight here as the paint can is a bit too large. [attachment=223294: DUCTS INSTALLED.jpg] While the glue is drying I made up the 'modified' throat sheath braces. When all the glue was dry I glued and stapled the throat sheath braces in place and sealed the tophat holes with glue. [attachment=223292:BRACES.jpg] [attachment=223296:BRACES INSTALLED.jpg] Now comes one of the few bits of actual manual labour involved in the build. I had to sand the front of the duct to an angle so that from the edge of the brace to the bottom of the duct was not a step. This took about a minute per duct. I also made a strip of ply that slotted behind the braces so that there again was not just a butt joint between the throat sheaths and the baffle. Everything here is tabbed or slotted so that it just pops into place. [attachment=223296:BRACES INSTALLED.jpg] All glue that had squeezed out where I didn't want it was chiselled off and the throat sheaths were then glued and stapled in place. The throat sheaths are also made from flexiply and are slotted into the baffle. The last thing to glue is the phase plug dome. Polyurethane glue does the job a treat. I was a bit concerned that it might might melt the polystyrene but all is OK. [attachment=223295:INNER HORN & BALL.jpg] I also found out that the glue gets on your hands really easily and doesn't want to come off again. I also found out that once it's on your hands the finger print recognition on an iphone stops working. Edited July 11, 2016 by bertbass Quote Link to comment Share on other sites More sharing options...
bertbass Posted July 11, 2016 Author Share Posted July 11, 2016 [quote name='3below' timestamp='1468266685' post='3089761'] 20 mm/s is a pretty impressive cutting rate. Apart from the upfront capital costs I can see many advantages of laser cut for sheet work, not least no dust (other than initial down size from 8 x 4), no blade sharpening, much less edge fettling etc. Any thoughts of selling flat pack BFMs? [/quote] I've not yet been able to buy an 8 x 4 sheet of ply for the laser. It's ply specifically for laser cutting and is not readily available. It's all to do with the glue that glues the plies together. Normal ply just burns. Once I've finished the build and confirmed that everything fits together as it should, I shall be making kits available. If anyone is interested, P.M. me. Quote Link to comment Share on other sites More sharing options...
discreet Posted July 11, 2016 Share Posted July 11, 2016 [quote name='bertbass' timestamp='1468267453' post='3089766'] I shall be making kits available. If anyone is interested, PM me. [/quote] THAT'S what I wanted to hear! Quote Link to comment Share on other sites More sharing options...
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