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  1. #16
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    I would not worry about the bucket list running out. When you have made an instrument that plays the bug often bites and you want to improve on it with the next one.
    Regards
    John

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  3. #17
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    Jan 2021
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    Canberra
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    Milestone this weekend - I finished construction of the soundbox and have just set up the pillar/neck joint. I have just cut out the last two pieces of the puzzle - the cheek pieces to go over the pillar joint and have also finished shaping the neck extension. The laminated piece on the left of the neck was a solution to a mistake - I sanded too far and had to remove the entire lamination and redo it.
    So now it is sand away and then varnish.

    First off I attached a trim piece that sits on the front base under the pillar. I laminated a thin strip of Blackwood to some Spotted Gum and set it up to glue around a curve the same diameter as the base so that minimal clamping was required to hold the shape on the harp. I then drilled holes every two inches and inserted bronze screws I had left over from when I built my boat.
    The I drilled and attached the feet so it is now standing on it's own legs.

    Need some advice now - when sanding the veneer the black dust that came off it has stained the plywood down near the trim piece. What is the best way to take care of this do you think. I was thinking about using my air gun and a old toothbrush to get out what I can. It is very thin plywood and I don't dare sand this area much.

    Trim Piece.jpgAttachment 491587
    Attached Images Attached Images

  4. #18
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    Feb 2007
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    blue mountains
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    Not sure on the staining. Harmless methods are dry brush and or vacuum. Other less harmless ways are damp cloth or cloth damped with turps or sprit. Compressed air could also be a go but I would take care and not get the nozzle to close as you risk doing damage to the inlay. If all that fails and you have to sand then hand sand with say 400g. Careful approach needed.
    Regards
    John

  5. #19
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    Jan 2021
    Location
    Canberra
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    On the home straight now. All construction is complete with the installation of the pillar cheek pieces. Sorry about the black and white photo - I tried to show detail and the light isn't great in my workspace to help. There is nothing at all about the attachment of the cheeks other than sanding them as close to the finished shape as possible before attaching with another clamp balancing act. They are very close to the edges of the finished pillar so care needed to be taken not take too much of the pillar when I was rounding the edges. The step up to the cheeks in the finished product is quite pleasing.

    harp final construction.jpg

    What followed was a massive amount of sanding using hand, orbital, multi-tool, and sanding pads. Sorry but no photo's of that process as my glasses were covered in saw dust and I couldn't see straight to take the photo The timber I took to 240 grit and the plywood I took to 400 grit

    In the original shaping I had a bit of tear out I knew I would have to deal with at this point. In chasing the tear outs I changed the shape of the pillar slightly however the end result is very good. In the end there is only one spot I could not get all out and that is directly under the neck so won't be obvious anyway. If you look close in the neck photo under about the ninth hole you will be able to pick it up. The face of the neck has to remain flat in case I want to mount levers at a later date so I could not round over the face to hide the last bit of tear out.

    I have put on the first coat of gloss varnish and will let it harden till tomorrow when i plan to sand back with 400 grit and then put on another three coats. The timber is popping already and the struggles with the spotted gum are now paying dividends. I did ask about staining at the base. I decided to not chase it too much. I did clean it up a bit but there is still some there but I am not overly fussed.

    front first coat.jpgshoulder first coat.jpgNeck first coat.jpgCheek first coat.jpgfeet first coat.jpg

    Once I finish all coats and start the hardware installation I will post again.

    Mark

  6. #20
    Join Date
    Jan 2021
    Location
    Canberra
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    Good Morning all,

    I put on the final of four coats last night so now it is just sitting quietly hardening up. Thankfully I was able to get in and out before the bugs were attracted to the light and there are no stuck legs or wings in the finish. Sorry about the photo's on their sides - they are right way up on my computer and I am tired of wrestling with the damn things.

    Neck final coat.jpgFinal coat.jpg

    Now I am reading the hardware and string installation instructions. This part of the instruction booklet does not matter if you are building from plans or a kit so it makes sense. My biggest concern will be the hole sizes however the hardware kit came with the stipulated drills so in theory it should be all fine.

    The hardware kit is totally complete right done to little nails for attaching the soundboard to the sides. These nails didn't survive first contact with the hard spotted gum so I subbed them out with some better nails in the end as I got sick of pulling out bent nails. I also used exposed bronze screws in place of standard screws and plugs (also supplied) for accent pieces and stainless screws - because I had some - for wherever else they were needed such as the feet attachments.

    Tools.jpgStrings Pack.jpgHardware pack.jpg

    I will be using the rest of the hardware supplied as is as it is specialised pieces. Also the strings I am assuming are good quality and I don't know any better so they will be used as is.

    Once I start the installation I will post some pictures of the process. Ans hopefully my soundboard won't explode with all the string pressure.

    Have a great long weekend wherever you are.

    Mark

  7. #21
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    Jan 2021
    Location
    Canberra
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    well that happened fast.....

    I couldn't help myself and put in one brass collet to see if my holes were drilled the right size and before I knew it all 31 were in.

    brass collets.JPG

    Then its a case of I wonder if the bridge pin holes are right.....

    threaded bridge pins.jpg

    They were and all of a sudden all 31 are in....
    Off course I then have to see if the tuning pins would fit nicely....two of the pins were not as firm as I would like so I will have a think about that tonight. I guess the drill must have had a bit of wobble in those two holes or as they are right next to each other I wonder if the wood in the centre of that part is a bit softer.

    threaded tuning pin.jpg

    and before I knew it all hardware is installed ready for stringing in a day or so when the varnish has a bit longer to settle - just like I said this morning about the hardware.

    all hardware.JPG

    Here is a picture of the neck and pillar joints - there is meant to be a gap around the pin of the neck joint - it is a floating joint. There is also a gap completely around the pillar foot so that the string vibrations on the soundboard are not impacted.

    Neck Pin.jpgPillar soundbox.jpg

    Construction wise I only have to put on the feet and position and screw in the pillar foot in its final place - then string the while thing up.

  8. #22
    Join Date
    Jan 2021
    Location
    Canberra
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    Well I have been avoiding this post - sulking in my moaning chair in the shed with a beer and lamenting the wood stores all closed for Easter.

    I strung the harp and it was sounding brilliant - the soundbox worked out beautiful and once the strings took the tension and the spaces came away from the soundboard it just came to life....then....
    The neck failed catastrophically at the lowest point of the dip. It didn't damage the soundbox somehow so I dodged a bullet there to allow me to salvage all of the hardware and redesign the neck. But I am still quite despondent about it.

    So what happened? Doing a google for Harp Neck Breakages it would appear that where mine broke is the same point where they all do. In my case I also found a couple of serious problems. The most serious is that the break occurred on one of the joints for the front layer - and that break was clean - meaning that the joint was starved of epoxy. Second the grain structure was wrong for this point - vertical instead of horizontal - and finally to make sure it broke one of the holes for the tuning pegs goes right through this point.

    Neck Broken.jpeg

    So what's next?

    I am redesigning the neck to flatten the curve and provide more beef above the neck. I found a design I really like and will do something like the following as it still looks curvaceous but has good bulk. I will also be able to keep the string holes in the same positions.

    better neck design.jpg

    I have also just ordered some carbon fibre cloth to sandwich between the laminations and to top it off I also ordered some Carbon fibre bars to inlay between the layers ala guitar necks.

    So instead of signing off from this post for good I am continuing for a while and will keep posting once I get the new timber - probably blackwood and maple - and carbon supplies and go again.

    Mark

  9. #23
    Join Date
    Feb 2007
    Location
    blue mountains
    Posts
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    Very sorry about your setback. Better luck next time round.
    Regards
    John

  10. #24
    Join Date
    Nov 2004
    Location
    Millmerran,QLD
    Age
    70
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    9,106

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    Mark

    Good that you are philosophical about the mishap and better that you can salvage some of your work. I can't say that I would have accepted such a setback as well as you.

    Regards
    Paul
    Bushmiller;

    "Power tends to corrupt. Absolute power corrupts, absolutely!"

  11. #25
    Join Date
    Nov 2011
    Location
    Melbourne
    Posts
    5,567

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    Mark,

    Good on you for keeping going, Iíve been following along on your build, an do get so close then have that happen, well that just sucks.

    Iím really impressed you got of the work shop floor an have moved on

    Cheers Matt.

  12. #26
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    Jan 2021
    Location
    Canberra
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    Thank you to all the messages of encouragement.

    Good thing about having to work to pay for the hobby is that it allowed me time to work out a plan so that the disappointment of a week ago is long gone and I am now impatient for the carbon fibre cloth to arrive so I can get back into it.

    I bought a long length of Queensland Maple in width wide enough to cover the entire neck without having to glue up to make up the width, and with the grains running horizontal through the neck. At over 1" thick before dressing I can also get away with two laminations instead of three. The Timber came from Monaro Timbers here in Canberra. Because of the width it was expensive but hey if it results in a stronger neck and makes me be more careful with my layout then I am comfortable with the price.

    I am playing with the neck shape in plywood templates at the moment and think I can keep the basic shape of the front of the neck but increase the width of the spine in the back lamination. I also will add about 1/2" to the bottom of the front face to make sure there is room for tuning levers if I decide to fit them at a later date. This will also add some extra to the suspect curve without affecting the aesthetics.

    IMG_1163[1].jpg

    The pillar was collateral damage to the neck breaking as it was attached very well and won't be coming away in one piece so I committed to making a new one out of the maple. Besides I won't be using a contrasting piece this time so it would look strange anyway.
    The Maple I have is quite reddish compared to the blond neck on my guitar. It isn't too far from the spotted gum on the soundbox but I may have to consider a tint to tone down the red a bit - I will work that out once it is all put back together and if I really care in the end as I like showcasing Australian Timbers if I can.
    I have also received fresh epoxy supplies including some slow hardener so that I am ticking all the boxes to plan for success.

    That's it - Carbon fibre cloth is expected next week sometime so I guess I should start making a Queen bed for my son like I promised ages ago whilst I have the chance, or I could put in the boat and go for a sail.

    Hope all are well.

    Mark

  13. #27
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    Jan 2021
    Location
    Canberra
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    Quick update, I have glued up the new pillar...nothing exciting in the process. I did make the edge furthest away from the soundbox about 1/2 inch wider than the original to give it a bit more aesthetic impact - the original seemed a bit spindly against my new neck template. The only photo is of a whole heap of clamps as every possible clamp and space was used so I won't put it up here. I got a bit distracted getting ready for the glue up by doing research on any issues gluing up Queensland Maple and got lost in an article on the West Systems website on silicon in fabric softeners and how acetone can release them from rags into freshly sanded timber. I don't use rags for that purpose but a good way to waste an hour or two on a Sunday afternoon learning something.

    neck template.JPG

    The template here was about the third last one but the shape remained largely the same - I made up five templates in all. The original outline can be seen in the photo and if you look close I have also marked the tuning peg holes. My final version is about 1 inch wider at the thinnest point than the original and I have kept the hole positions where the designer placed them. The photo seems to make it bigger than it really is - my wife says it is all in perspective with the soundbox and the new design is in keeping with the gothic theme of the harp.
    My intent is that I will glue up the entire neck to the new wider dimensions with the carbon fibre reinforcement but then sculpt the front face down to the original line at the top only which will also make it look less bulky whilst keeping the extra bulk on the spine. The lower edge is only slightly wider but this is enough to ensure I have more than enough room to install levers at a later date if I want to.
    I also made the curves near the pillar and soundbox more relaxed and finally I also made the neck where it joins the soundbox about 1/4 inch wider so that there will be heaps of meat for me to shape the final piece to the soundbox.

    That's it for now

    Mark

  14. #28
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    Jan 2021
    Location
    Canberra
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    Its been a while and I have been making progress, just hard as everyone knows to balance quality shed time with quality family time and work.

    The new pillar went together boring and simple so nothing to really report. The Queensland Maple worked far easier than the Spotted Gum and the finished structure is significantly lighter than the previous neck and pillar so I hope that won't bite me in a day or two when I string it again.

    The new neck was more complex, First I laminated 12mm wide carbon fibre bar into the inside lamination of the neck. because of the bend in the neck I couldn't have it straight across as would have been preferred so I used one piece on the bottom of the curve and two vertical pieces on an angle up the sides. This was placed in a tight groove and epoxied in with some epoxy filler and capped with timber strip. Sorry no photo's of the process but the attached does show the pattern I ended up with.

    Carbon inlay.JPG

    The neck was then laminated with lots of west epoxy to ensure that the carbon weave was saturated. Very slippery stuff. I know the photo is boring but for information of the curious it is 7oz plain carbon cloth at .25mm thickness. At about $82.00 per meter I don't know how it compares in price to other methods but I have heaps left for other projects. I am happy with the supplier timeliness and cost of West epoxies when compared to the usual stores but don't know if I am allowed to mention businesses in the forum so please let me know if your interested. The green edge is simply painters tape so that I didn't get loose fibres as I worked it - they were a real pest. It cut far easier than I expected whilst it was still green epoxy but once cured that was a different matter and let me tell you carbon splinters hurt far more than timber. It was like glass to sand and it took a very aggressive grit to get it moving. Once I got to the point of finish sanding however it was far easier and I hardly noticed it. The carbon bar however put black dust over everything so I have had to be careful with my finish sanding.

    Carbon Weave.JPG

    So fast forward and the rest of the construction was straight forward - groundhog day really.
    I did get the chance to correct some things I didn't like on the first neck such as the thickness of the neck side lamination including leaving excess material to allow matching the soundbox curves front and back.

    Rough Sand.JPG

    Last night I glued on the neck / pillar cheeks so I could finish sanding and get the first sanding coat of varnish on today. These photo's are before my final sanding session so the cheeks are still rough and dirty - as is the rest of my shop looking at these photo's - must do another clean up.

    IMG_1238.jpgHarp.JPG

    With the fit all good and happy with the edges and shape I gave it the first coat and will now do other stuff for about eight hours.

    First Coat.JPGCarbon line.JPG

    And that's where I'm at. If all goes to plan I will put on the hardware and string it - again - on Monday afternoon. Like I said I am worried about the weight of the timber BUT I know it is far more structurally sound given the far fewer laminations, no but joints, copious amounts of epoxy so no starved joints, carbon rod and carbon weave, and finally there is significantly more meat in the neck redesign. If however it breaks again I am sure you will hear my scream from wherever you are reading this.

    Mark.

  15. #29
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    Jan 2021
    Location
    Canberra
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    Well fingers crossed this is the end of the harp journey - it is strung - not up to full tension yet as I am letting the soundboard and neck settle at about 3/4 tension. Listening carefully for creaks and groans. Also apparently the harp needs constant retuning every day for a couple of weeks as the strings stretch so starting of slowly puts me more at ease. So far there is zero movement in the neck so fingers crossed. Even out of tune it is loud and vibrant - very happy with that.

    The Queensland maple came from a single sheet of timber yet the colours are significantly different between the neck and pillar. It is quite different from the soundbox but to be honest it is quickly growing on me. Everything apart from the soundboard itself is Australian timber so I have satisfaction from that.

    For a round up - sides and braces are all spotted gum. The soundboard and back are 3mm Aircraft Grade Finnish Birch ply. The neck and Pillar are Queensland Maple. The neck pin is a piece of really heavy red timber from my offcuts bin - I think it is Sydney Blue Gum.

    Harp playing side.JPGLeft Side.JPGFull Neck.JPGRear neck Joint.JPGNeck Joint.JPGInside box.JPG

    The string guides and tuning pegs are all factory bought and screwed in to about 5/8" proud. They have a very fine machine thread not really suited to timber I would have thought but they seem to hold nicely.
    The inside photo shows how I attached the strings. They are pushed through from the front brass collet and through a small hole in each dowel before being tied off and the knot secured with a dap of super glue. I didn't want the knot or a small bead to be against the soundboard as I thought it would create 31 pressure points so the dowels were my preference.
    The neck pin is floating only held in by tension and the base of the pillar has a screw through the base. This allows for repairs and transport if required. I actually like this joint as it is pure simplicity - nothing more nothing less.
    The plans and hardware are from HarpKit.com. There were quick and easy to deal with and everything supplied was ok. The screws and nails were not what I would recommend as I think I bent every single nail till I swapped them out. The screws (used on the base and feet only) snapped off every time I tried them so I replaced them with stainless.
    The plans themselves were ok but not what I would recommend for a beginner as there was a fair bit of information I had to work out as I went along. I believe their kits are much better for a beginner. The neck joint is a case in point where there were some angles and measurements missing and there are a lot of both of them in a very small piece so it took three goes before I worked out that puzzle. There is a warning on the plans that after years of copying that the measurements may be inaccurate and I certainly found that to be the case.
    The instruction manual is for the kit only not the plans so apart from some guidance on staging and hardware setup it really wasn't that useful.
    Finally the way my mind works I figured I would only ever make one harp so make it a good one and I bought the second largest model plans from the company. This thing is about 5 foot and even with the lighter Maple is still heavy. If I had time again then a smaller 20 string or shepherds harp would be more sensible.

    I am not sure what else to describe. I will tension it fully over the next day or so and then move onto the next project which is a queen bed for my youngest - but he will be creating the sawdust - I will just help him along making sure he knows how to sharpen my edge tools and keep all his fingers on his hand. For me I think I need a mobile clamp/gluing station for the shed...and some new clamps for that matter.

    Mark

  16. #30
    Join Date
    Feb 2007
    Location
    blue mountains
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    Really glad it's worked out. I was not game to say anything after your last post in case I jinxed things.
    Great thread and a stunning looking instrument.
    Regards
    John

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