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Harlequin

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  1. Harlequin
    This afternoon I worked on using the parts to put together one baseboard.
     
    Cut the parts to exact length in the mitre saw. This ensures that the parts are exactly square and gets rid of any rough corners.

     
    Cut the PSE that strengthens the ends of the frame. It's not the best quality and although it was reasonably straight and not twisted it was badly bowed so I ran the pieces through the planer just to square things up a bit without changing the dimensions too much.

     
    Glued the PSE to the end frame ply. I might add some screws later.

     
    Cut half depth slots in the spine and rib pieces using the depth stop in the mitre saw.

     
    Did a dry run on the workbench:

     
    So far so good. No major disasters, yet...
  2. Harlequin
    I made some more progress on my open frame baseboards today.
     
    I glued and screwed the side pieces to the ends to create a flimsy frame.

     
    I drilled out some holes in the rib and spine pieces. The exact position of these holes isn't really important but for neatness I clamped the ribs together and drilled through all 5 at once.

     
    Then I glued the ribs and spines into their grid pattern. Some of the fits were a bit loose so I had to weigh everything down while the glue dried.

     
    When the grid was set, I fitted into the frame and glued and pinned it in place.

     
    Some of the pins were too close to the edges of the ribs and they split but it's not a problem because the edge stiffeners will be glued over the splits
    The two spines don't meet the ends, as expected because I had to plane the PSE pieces down to remove the bowing in them. It just means that I'll have to fix some blocks to join them to the ends.

     
    I'm not worrying about squareness yet. I'll get the unit exactly square when I fix the edge stiffeners and corner braces. However I am worried that it might not be strong enough - the acid test will be for me to sit on it while it's only supported at the ends...
  3. Harlequin
    I bought some pattern makers dowels at the Exeter MRS Exhibition:

     
    I also bought some cheap plastic saw-horses from B&Q:

    A little bit of modification allows the baseboard frames to locate securely on them.
     
    Things went awry when I tried to fit the pattern makers dowels:
    I used a 25mm forstner bit to make very neat pockets to house the dowels but because I was using a hand-held drill it wasn't exactly perpendicular to the surface and so the pockets did not have consistent depths. The dowels didn't quite line up when I offered them up and there was a step in the baseboard surface.
     
    So I had to resort to bits of cardboard packing and PVA glue to try to even out the depth and a 25mm spade bit to expand the hole. Urgh! It ended up a bit bodgy:

     
    But the two boards do line up pretty accurately, in the end:

  4. Harlequin
    I did a better job of fixing the pattern maker's dowels with the next baseboard connection. Practice makes perfect.
    This time, I drilled a small pilot hole through both baseboard frames while they were clamped together. (There was only just room to get my small Makita drill in to do this - something to maybe plan better in future!)
    Thus, when the frames were unclamped the pilot holes were exactly aligned where the faces meet. Then, using these pilot holes, I was careful to hold the drill perpendicular to the face while I used the forstner bit to drill out the pockets for the dowels.

    Much neater!
     
    Since the pockets were more accurate I went ahead and screwed the pattern maker's dowels tightly into the pockets and offered the boards up to each other. Clunk! Perfect fit and alignment is acceptable.


     
    So I now have the three main frames joined and bolted together on the trestles.

     
    Next job: Construct the twin track bridging section to span between the horns of the "U". It will be an H cross-section of 9mm ply with 78mm deep cross-bracing below the track bed. The taller sides provided by the H should prevent the 1440mm long bridge from sagging in the middle.
  5. Harlequin
    I drew up a quick set of plans for the bridging section to get it straight in my mind:

    I made the side panels and the track bed all the same width, 140mm. That made cutting a bit quicker and simpler.
     
    Some ribs with holes drilled through them for wiring in the same style as the main boards were glued under the track bed:

    I added PSE timber pieces to reinforce the ends, provide a good solid support and some extra thickness for whatever locating and fixing parts I decide to use.
     
    To help locate the track bed properly I glued some support pieces onto the side panels:

     
    Then with the aid of a 6ft level to act as a straight edge, lots of cramps and some weights, I glued the track bed to one side panel, then the other.

     
    And here's the bridging section temporarily clamped into place between the other baseboards:
    It will need a bit of fettling to allow it to drop in and out easily while maintaining tight tolerances and accurate alignment at the junctions.

  6. Harlequin
    I glued a ply top to the central baseboard frame at the weekend. That was rather stressful because it was very hot and I had to get glue onto the top edges of the frame and all the ribs and spines as quickly as possible before dropping the big 1440*720 piece of ply precisely on top. In fact I ended up just gluing strategic points and the surface board did not end up as accurately aligned as I would have liked. Hopefully good enough, though...

     
    I have also cut and fixed quarter-circle pieces to provide continuous track bed around the entire circuit now:

    The curved pieces are only screwed down so that I can change things in future if I need to. I will probably add further track bed inside the curves at some point.
    There's one annoying joint where two bits of the 9mm surface ply seems to be different thicknesses ans so there's a step. I need to look at that.
     
    So I'm getting close to actually laying some track! Not sure If I should bother with cork or not...?
     
    And I'm also wondering if I should start a thread in the "Layouts topics" area. This is never going to be scenic, it's just a dry run for the techniques, to test electronics and DCC settings and to let locos stretch their legs.
  7. Harlequin
    I realised I needed to make a roundy-round test track so before I get into making the complex baseboards for Hampton Malstead I have decided to make some simpler baseboards for the test track using the same basic techniques.
     
    Here's the plan for one of three identical boards which I will arrange in a U shape with a thin bridging piece across the top of the U to allow a continuous circuit of track to run around.
     

    Open baseboard.pdf
     
    I brought a sheet of 9mm ply up to the workshop during the week and ripped it into 6 smaller pieces: Long for the sides, spines and stiffeners, medium for the ends and ribs and the remaining short bits for corner braces

     
    This morning I sliced them into 78mm and 69mm strips. It was hard to get straight edges on the 1440mm long pieces even in the table saw because the fence wasn't long enough and the sliding table only slides 1200mm. (Note to self: Maybe design basebords that are only 1200mm long next time.)

     
    I Googled the problem and the simplest solution was to clamp a long straight edge to the table to form a longer fence. I used my 6ft level and some tricky adjustment was needed to get the fence set at the right offset. I think it improved things a bit but the edges were still not as straight as I'd like.
     
    So, I now have a stack of ply parts to make two baseboards, plus some extras so that I can select the best ones

     
    Meanwhile, outside:

  8. Harlequin
    I dismantled the baseboards from the middle of the living room and erected them in a more out-of-the-way corner. This is still not an ideal location because other furniture has been displaced and I have nowhere to bring in my huge specimen Strelitzia plant for the winter - but we'll deal with that when the time comes.
     
    In the meantime, having the layout more permanently set up has meant I've been able to push on with laying cork trackbed and actually laying some track!


     
    This was the track plan:

    I used a curved point (green) on entry to the back sidings because during planning I found that it caused less deviation from the curve radius than a small left. More on this later...
    I've left on some of the construction lines and you can see that I briefly considered transition curves (orange) between the straights and curves but since the layout is for running-in and testing locos I decided it wasn't worth the extra complexity.
     
    The trackwork is all Peco code 75. I drilled holes under all the point tiebars in case I decide motorise them one day and brought all the frog dropper wires through the baseboard as well. (I didn't snip any bonding wires under the points before I glued them down - this may prove to be an error in the future.)
    All the track of the main circuits and points leading to sidings was pinned in place temporarily then glued down with PVA and the rails were soldered to copperclad strips on either side of the baseboard joints.


     
    Every section of track has dropper wires waiting to be connected but I realised that if I just wired up one or two pairs of droppers I could actually run a loco (relying on the joiners alone to supply power around the entire layout).
    Here is the glorious moment when the first train ran:


    The Barclay 14in is a smooth little runner! 
    Since I took that video I have cut the rails at either end of the bridge, lifted it out, put it back with it's own power feed and the Barclay still runs smoothly across the joints with a satisfyingly solid-sounding "click-click". It's a relief to know that the combined board alignment and copperclad rail alignment do actually hold everything accurately in line!
     
    P.S. 40 years ago I used to cut track with a junior hacksaw and it was always a painful experience, in every sense. Now I have a Dremel equipped with a metal cutting disc - Deep Joy! ;-)
  9. Harlequin
    Over the past few weeks it's been hard to motivate myself to do anything, aside from drawing stuff on the computer, which is always satisfying.
     
    So this weekend I decided to just do something, anything just to get myself going. So I built a workbench for model making so that I don't monopolise the dining table any more.
     
    The work surface is 18mm ply with a frame of 50*50 PSE bracing for strength and to straighten out the ply, which was a bit warped.
     
    Sides and shelf are 12mm birch ply.
     
    The legs are a bodge up so that I could get the job finished before work on Monday - 50*50 PSE braced by 12mm birch ply. Time will tell if they need more bracing...
     

    Ply surface and frame being glued up in my shed.
     

    The finished article (apologies for bad photo - not enough light).
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