Building of Custom Rhapsodys

PACPAC
in Members' blogs
Thought I'd share a few progress snippets as I continue with a customers Rhapsody build.

Today was a little nerve racking as it was book-matching for the front panel veneers.  Forgive the poor photos as I only had the camera phone with me.  I'll take some proper shots with the main camera in due course.

Mocking up the part of consecutive veneer sheets to be used for the front Baffle:  Cardboard cut outs to represent the drivers and part of one of the ports all in position:

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Note the sap wood towards the edges and centreline.  This was cut out (about a 25mm strip) so I was left with two halves of reversed (mirrored) consecutive veneer sheets.  I chose the part of the sheets which gave the appearance of an hour-glass shape to the grain as if it was supporting the main drivers as this looked the most balanced pattern for the front.  

Next...selecting a section for the side panles: something less fussy with straighter grain edges (and the same for the top) was selected:

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Finally:   Top panel veneers cut and glued to the Birch ply, and placed inside a DIY veneering jig made with a double heavy duty bag fitted with a suction nozzle and hose attached to a vacuum pump.  Panels placed upside down (veneer side down) and you can make out the internal panel rebates for the vertical internal spine brace:

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Lots more to do this week but hoping to have most of the veneering completed by the weekend.  Next step is to assemble the jig for pulling all the internal and external panels together ready for gluing up early next week.  I'll be working with an associate on this as two pairs of hands will definitely be necessary!

Crossovers already completed and ready to go in to the cabinets once glued up:

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Comments

  • DocfosterDocfoster
    Great blog Paul!
    Keep it coming. :)
  • PACPAC
    edited July 2014
    Some good progress today:

    Legs for stands made from solid Walnut cut and planed to exact sizes ready for morticing:

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    Internal braces have been returned from CNC shop ready for hand finishing and fitting to main panels:

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    Side panels for each cabinet cut and some of the rebates done.  I have to sort the mortice joints for the frame so still some work to do on these but they're now veneered (lying veneer face down at present):

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    I spent over an hour on this one plank alone picking the right grain and matching it for the frame top, bottoms, uprights and sides. Not straightforward as areas with defects have to be avoided and the straightest grain chosen for the featured front top and extra depth base sections. There's 2 cubic feet of premium Walnut here so even before investing in the time to choose each and every section to be made into the frames, it's a lot of money tied up in just this one plank (around £80 a cube for premium walnut these days). The frame sections will be cut tomorrow or early next week following which they have to be inspected for defects, planed to size, reinspected and sorted/numbered ready for jointing.

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    Part of the plank which can't be used!: (yes, they still charge by the cube, irrespective of what defects are in the timber.  you have to expect and account for that when initially working out the quantity needed.  I always allow a 25% margin for these things and often need it).

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  • DocfosterDocfoster
    Love the process! Proper craftsmanship.

    (I'm chuckling as i compare it to my efforts with my (very much unmorticed) speaker stands yesterday.)
  • PACPAC
    edited July 2014
    RFC News now updated.  View the news pages HERE if you'd like to follow the build as it progresses in a little better detail. 
  • DocfosterDocfoster
    Thanks Paul. I will be so doing...
    How often are you likely to be updating your webpage...?
  • PACPAC
    Thanks Ben.  Possibly once per week from now on, although I will also be transferring some of the more popular articles across from the old website as they're still relevant (things like how an MC cartridge works, or setting uyp loudspeakers etc)
  • PACPAC
    Some more progress:

    Some good progress this past few days.  Should be in a position to get the cabinets ready for gluing and cramping up by first thing next week but for now, been having a few issues with the CNC referencing, so resorted to cutting joint rebates using a router.  CNC in action cutting out one of the grille panels:
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    One of the front baffle panels ready for a final sand down prior to jointing the walnut frame and veneering.  Note the baffle depth ;)

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    Book-matching the rear panel veneers.  Takes a steady hand!  Here, I've used consecutive ply sheets, cut off the sapwood from each side of the sheets, and mirror-matched the sheets which have then been veneered.  This panel's just been removed from the vacuum press:

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    Closer look at the panel veneer matching:  No join should be visible.  If it had been, I'd have had to scrap it and start again:

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    Two veneered side panels with the Walnut frame edging being glued into place before final planing to size and jointing:

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    Walnut stands now having been assembled need a lot of work to finish.  Assembly was done using mitre-tongue biscuits (not the more normal oval shaped biscuit joiners). Here, your's truly is marking before routing in the recesses for the feet bases which will be epoxy glued in at a later stage.  Before then all 48 corners on each stand need a slight round sanding on them otherwise the final finish wont take properly and then all 48 faces need sanding with 180 then 240 grit sandpaper ready for the Danish Oil finish.  These are a lot of work:

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    One stand all ready for Danish Oiling, having just had the gold plated adjustable feet set and glued into place:

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    Next week should see the cabinets coming together, Tomorrow sees book-matched veneering of the front panels once the Walnut frame's been glued into place.  The final assembly will need several pairs of hands due to the complex nature of the jointing and internal bracing.
  • DocfosterDocfoster
    That's a proper job going on there Paul.
    Thickness of baffles duly noted!
  • uglymusicuglymusic
    That looks great Paul.
  • PACPAC
    Thanks chaps.

    A little more progress today...finished the stands:

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    Front panel was fitted with magnets pre-veneering stage and the magnets inset slightly and skimmed with epoxy before sanding back:

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    Got the veneering completed too and will post the next pictures as we assemble the cabinets.  I'm currently working on the grilles whilst Adrian (who's workshop I use for RFC builds) works on getting the panel frames routed to the correct thickness.  Between us, we should completed the cabinets by the end of next week if not early the following week depending on how we get on.

    The most challenging aspect is assembling and fitting all panels and braces together as these need to be millimetre perfect prior to gluing up, so lots of fiddly minor alteration work is in the pipeline ensuring that all braces fit perfectly into the panel internal rebates to pull everything together, plus the frame end and panel joints need to be cut and a dry run for fitting done.  These would not be easy to mass produce cheaply! 
  • sovereignsovereign
    Looks lush Paul!
  • PACPAC
    Thank James.

    Some more progress. All panels veneered now, and spent the day fine tuning all joints to get the things to fit together properly which threw up a few interesting challenges, but finally got the left hand cabinet front baffle, sides, top and base glued up.

    The internal bracing will be fitted tomorrow but part of the bracing structure (minus the vertical spine) is shown in one of the photos below.

    After a few dry runs, the final gluing up is on the bottom photo...loads of sash clamps needed:

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  • DocfosterDocfoster
    We have 3 dimensions!
    (Are you sure you're using enough clamps there Paul...?)
  • PACPAC
    You can never use enough ;-)

    Slow progress today as some of the internal bracing has to be shaved down fractions of a millimetre to get the backs to sit properly where they ought to.  Still, bracing all in and glued up, acoustic foam in place, and both cabinets glued up this afternoon so two more days should break the back of what needs to be completed prior to final finishing work:

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  • DocfosterDocfoster
    The internal bracing is very pleasing to my 3D spatial awareness. Seems a shame to seal up the cabinet and hide them Paul. I assume that you'd claim that leaving the backs open would effect the sound in some negative way... ;-)
  • PACPAC
    errrr...just a little!


    Here's progress as of this afternoon.  I've completed the grilles (the air turned blue at various stages of fitting the fabric) and the majority of the work is now done. A few days left on final finishing works and we're there. The RFC speaker "team" is shown on the bottom photo (myself and Ade).

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  • DocfosterDocfoster
    Cripes that wood looks stunning on them there stands. Take off those grilles! :-p

    Fantastic workmanship fellas. You look rightfully proud in that last one. :-)
  • PACPAC
    Cheers Ben.  The main cabs will darken and the grain will be more prominent once we start work on the finishing.  At the minute we have a cabinet each to work on for edge rounding and the final rub down before Danish Oiling.  I've also got a fair amount of work left to finish the stands too as the finish on both cabs and stands will be a deep lustre rather than matt satin, so coats have to be built up gradually and gently rubbed back between coats.
  • uglymusicuglymusic
    They look good Paul.
  • PACPAC
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    I'm having a week off now...
  • DocfosterDocfoster
    Ooooo...

    How are they sounding...?
  • PACPAC
    Oddly enough Ben, they sounded great from the word go so wont need much breaking in, although they will still improve with a hundred or so hours on them as the suspension gets a little more compliant.  The big caps used in the crossovers stabilised fairly quickly.  Bass seems to be well extended with good texture, even at lower volumes, mids are a real strong point...very natural indeed and the tweeter doesn't draw attention to itself at all, but the detail is there. The drive unit choice and crossover design means that the driver integration is totally seamless. I'll post a few response graphs once they've had a little more time on them.
  • DocfosterDocfoster
    "Oddly enough..."
    :-)
  • uglymusicuglymusic
    We likes texture, we does ;-)
  • PACPAC
    Here we go....pleasingly, they're closely matched. This is BOTH left and right speakers.  FR is 32Hz to 25KHz (-6dB).  Tempted to keep this pair but sadly they're spoken for!


  • PACPAC
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  • DocfosterDocfoster
    That's close! :-)
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