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  #16  
Old 01-19-2018, 08:06 AM
printer2 printer2 is offline
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Default Making a radius dish

I came across this thread on making your own radius dish and it sure beats using a router and hogging out a piece of MDF. It has pictures that are on Photobucket and we all know what happened with their picture hosting. On page 6 there is a couple of links that can make the pictures visible again. If not there are two pictures that show the end result hosted on the uke site..

http://forum.ukuleleunderground.com/...-a-Radius-Dish
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  #17  
Old 01-19-2018, 10:03 AM
charles Tauber charles Tauber is offline
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It looks like an effective method for making one's own radius dish. Thanks for posting it.
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  #18  
Old 01-19-2018, 10:45 AM
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I read that same article once and it inspired me to make workboards in the same manor. Back when I read it the photo bucket pics were shown

I made a work board to built Selmer guitars and one to built mandolins which has a very similar construction. The radius is lateral and the top is canted (pliage). But the principal was the same, screw and or glue thin plywood to arched braces:



The other method I came up with for building 'flat top' guitars with an arch on an open work board is to go to a hobby shop and buy thin sheets of balsa in various thicknesses and laminate them to a flat board. THen using arched sanding sticks made from band sawing a 2x4 I sand out the bowl shape into the lower bout area. The Balsa sands very easily away. Then once it's done you glaze the whole thing with epoxy to set it in stone. Works like a champ.



Anyway I'm loving this shoestring build. It's so cool to build instruments like this and I'm sure it will come out great.
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  #19  
Old 01-19-2018, 01:45 PM
printer2 printer2 is offline
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Thanks for the pictures. Why do I have the sudden urge to build a mandolin? When I first started this project I just wanted to encourage the odd person or two they could build something without too much of a hit to their pocket book. I never imagined doing this amount of documentation on it. The box feels pretty good, might be an instrument in there after all.


Been busy. glued on the lining. The sides have been sanded close to finished height so the lining needs to sit a little proud of the side. We will then sand the lining down to the side height. These paper clips are great for the job. I almost forgot to mention, I used a razor knife and whittled away at the sides to get them close enough before I started with the sandpaper. Shavings in the picture.



All glued on. I also sanded the linings till they matched the side edge. I only used one sheet of 60 grit sandpaper clamped at the two corners to the bench. I just rotated the body to sand the other edges. You do lift up the body a lot to check how you are doing and adjust doing one corner or the others to get the body to fit right to the bench. I do the same thing when using a radius dish. Not unusual for the sandpaper to get the worst of it.



Here I am marking off the braces where they exit the body. I cut them a little short of the body so they sit under the lining but there is enough gap between the brace and the side so if the brace expands it does not push through the side. I mark the center strip and measure the neck block. Also cut it back so the strip does not interfere with the neck block. Both the front and rear blocks are shaped so that only about the width of the linings will contact the back when glued.



Notched linings and shaped braces. How do I know how much to shape them? Just a guess as with the top.



I was going to show the rope method of clamping the back to the body with some surgical tubing I have. But that is shown online enough and I had another idea. I taped the tubing to the back, flipped it over and made sure the tubing didn't move.



Did a trial run with the body, marked arrows on the body and the back to be lined up.



Time for some glue.



Started piling on. I put a clamp at the lower bout and adjusted it for the width. I did not want the sides to bow out, they didn't seem to. Now to wait a half hour or more.



Well it didn't collapse. I took a quick trip to the belt sander, I hope nobody minds. I wanted to see what it looks like a little dressed up. I would have scraped the wood if my wrist wasn't bothering me, still more work to do.




The top seems ok also. But for some reason something looks like it is missing.

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Last edited by printer2; 01-19-2018 at 01:55 PM.
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  #20  
Old 01-19-2018, 08:52 PM
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Need to cut the sound hole out and the simplest way to do it is use a Exacto blade and progressively cut deeper and deeper.



It is hard to see but I used the razor saw to cut a slot in the end of the board roughly in the shape of the blase. The blade is going to be clamped onto the board but as the blade is slippery it can slide out of place with the pressure that will be on it. I folded some tape over it to give the clamp a better surface to grab onto.



Here id the blade end sticking out and the clamp holding it in place. I cut a slot in the other end for the other end of the clamp. The drill bit stays in the board and acts as a pin to ride in the hole drilled in the top with the same bit. I did chamfer the edges of the board a little so there would be no sharp edges to mark up the top.



Kind of nervous at first because you never know...



First go round and it does not look too bad, It is a dull blade but the only one I have. It did not cut some of the grain lines cleanly because of that. Good enough for this cowboy.



And then it is just drop the blade down a little and go around slowly then repeat. I found that it was easier to have the blade sit on the slot it just cut, loosen the clamp, slide the board up a little, then clamp again. Always check to make sure your clamp is above the bottom of the board. I found it easiest to control the cutting by holding the tool in the center and spin it around.



As it cuts through just take it easy and you will be able to make it all the way around. A sigh of relief after that was over. Took about 20 spins around for those of you counting. For those brave enough you could have done a rosette the same way but stopping at a certain depth and then chiseling out the slot.

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  #21  
Old 01-20-2018, 08:35 PM
LouieAtienza LouieAtienza is offline
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Looking good so far Fred... I use a similar approach to cut my sound holes out, though I cut a piece off a cabinet scraper, and made it so it scores a groove like a scraper. Works just fine, good enough that I actually cut holes in acrylic with it! You can use a finish washer and screw to hold the blade for a more permanent solution.

Also for trimming top and back plates, when I don't want to make noise (i.w. late at night) I do it with an x-acto blade as well, with the side I'm trimming against a sacrificial board. The blade is flexible enough that it will bend tight to the side, and only takes a few passes to cut clean through.
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  #22  
Old 01-21-2018, 09:19 AM
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I think I will stick with my router and circle jig thank you. Nobody to bother here with the noise but the mice. From yesterday, finished up lat and did not have time to post it.

I bought a couple of classical rosewood bridges online from China, I can't even buy the wood for what I paid. I use one as a pattern if I want to build a bridge, for throw away builds like this I just plop one of these on. While you can build one with just hand tools I think the tricky part is getting the saddle slot right. I use a Dremel to router the slot, I guess you can cut it with a razor saw and then use needle files and lot of patience to finish it off. If you had a chisel the right width I could see doing it, I could make one but I think that would be out in left field for the type of person I am directing this thread to. That aside, A maple board from a hobby shop for the fretboard. When making the neck I prefer having the grain of the wood as shown. It just keeps the grain more perpendicular to the surface of the neck.



Truing up the top surface, well I thought I was. Afterwards I flipped it over and did the real top side. Wrote top on it afterwards. I did not have any short 2" x 4"s around so I used a block that I had cut and sanded at 90 degrees. Two sheets of 100 grit underneath and another upper body workout.



The end was rough from the saw so I cleaned it up with my file. Check with a square that you do not have it off at an angle.



Here we have the neck fretboard and bridge in place to see how things line up. We want the the straight edge coming off the fretboard and landing just on top of the bridge. I shimmed up the front of the body and the neck blank till everything lines up. Then I check the angle of the end of the neck blank to the body. I think I forgot to mention I had the neck block flat with a little bit of a radius at the sides. When I sanded and cleaned up the body I made sure the area where the neck with mate to was flat. This makes life easier when we join the neck to the body. If the end of the neck blank is not at the same angle as the body take the file, or sandpaper and block, and get the same angle.



Transfer the dimensions for the neck on the blank. I put a bought nut for a classical on the neck and drew a line from the string holes in the bridge to the end slots on the nut. Then I drew some lines for the overhang I want on the fretboard.



I cut the angle for the top of the headstock and then filed it flat on the vice. I put the block in the vice so the top of the jaws match the lines I want to file to. Then it is just file away till the file is level with either jaw.



Rather than use the handsaw I tried a hacksaw, I marked a line to follow well outside the thickness I want and cut a slot on either end and then down with the saw blas running down the slots I originally cut.



Something did not seem right and I stopped and cut down and knocked off the chunk. Looks like when I did the outside slots I was not at a right angle and the saw blade followed it and bowed cutting a hollow in the wood. At this time I am thinking I hope there is enough thickness left for the headstock, I don't want to glue up another board if I did not have to.



I cut the rest with the hand saw. Here I am cheating and using my drill press to cut a big hole at the heel end. I am sure you will forgive me, just saves doing a lit of filing with the round side of the file. I blame my weakness on the screw up with the hacksaw.



Cutting slots in the wood and then just knocking them out with a tap of hammer. I never went to the line as you do not have complete control how it will fracture and it is better to play it safe, easier to take away than to put back.



While the file does a good job if you have a fair bit to go using the round side can be faster. When you get close flip it over and square things up.



All cleaned up and marked for the next step. The headstock has just a little divot left. I tend to allow for the odd mistake when I lay things out, it saved me today.

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  #23  
Old 01-21-2018, 09:45 AM
LouieAtienza LouieAtienza is offline
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Router?? Thought you said you ysed a coping saw to trim the top, or misunderstood.
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  #24  
Old 01-21-2018, 10:33 AM
printer2 printer2 is offline
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Quote:
Originally Posted by LouieAtienza View Post
Router?? Thought you said you ysed a coping saw to trim the top, or misunderstood.
Router? Maybe you are referring to my using the Forster bit in the drill press? No my coping saw did not allow me to turn the blade 90 degrees. Also from my experience with the hacksaw I am more inclined to keep to taller blades for hand saws. Doing the multiple cuts to hog out the inside of the wood blank really was not that much time or effort.

I do change methods as I learn one way is better than the other. I normally would use power tools and have not done another guitar as I am with this one. The goal was not to make a guitar with no power tool but to show how someone might go about it. And while it is easy just to say use this or that tool but if you never done it you might not see the pitfalls in using them. So I am going through the build with the tools to see if it can be done.
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  #25  
Old 01-21-2018, 10:15 PM
printer2 printer2 is offline
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I have a jig which the saw rides up against the two dark plastic inserts. Works well and it is pretty fast doing a board. That is unless you cut the board to width and the edges diverge at an angle. At least I had the center line marked on the board and with the paper lined up I adjusted the position until the saw blade lined up over the fret line. A scale calculator which prints out the scale can be found at http://www.ekips.org/tools/guitar/fretfind2d/.



I read that you can use a couple of grains of salt on the board and this stops the board from slipping around once it has glue on it. Works well.



Trimming off the excess. At least the hammer is in focus. I have a piece of wood between the vice jaws and the fretboard, no reason to mark it up.



I drew some lines on the neck blank and started trimming with the saw and a spoke shave. The file works well also but the spoke shave is fun. This is where you have to mind the grain direction taking down the wood. It will let you know if you are going the wrong direction.



This is all done with the file.



I have to take down the heel a little and go over with some sandpaper. It comes to a point which helps me get the both sides the same but the point is going to come off. The headstock will take no time to finish up.

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  #26  
Old 01-22-2018, 04:33 PM
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Same idea as the jaws of the vice and filing a flat section. Two pieces of steel clamped where you want the flat to be. They do not need to be parallel or one can be angled and lower than the other (why you would want that I don't know of the top of my head) but another option to shape some wood.



Took away part of the pointy end. Keep working on it until it looks and feels right. Sometimes the grain lines do not get worked down as far as the softer bits, you will know when it is time to say, heck that is good enough.



Along with flossing the neck with sandpaper a few makeshift tools are handy. A scrap section of the top.



Packing material to conform to the curves.



As a final step I use the dull razor knife blade to scrape everything flat and smooth. I give it a slight bend when I do the curves.



Sort of a pleasing shape.



I don't know. I was going to dye the fretboard black but I might just leave it as is. I may have to give making a bridge for this one some serious thought. What do you think?

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  #27  
Old 01-24-2018, 12:53 PM
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Nooo, don't give up. It's fun to watch it all take place with hand tools and ingenuity. Keep up the good work.

There is one thing all luthiers, guitar builders, wanna bees and their side kicks like me own and use. We forget how important it is because it is such a common mundane item and we have used them so often throughout life that we give so little thought about it until we need it and don't have it.

A pencil is the one thing I consider to be a mutual necessity.
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  #28  
Old 01-24-2018, 03:07 PM
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This morning I thought, in for a penny, in for a pound. Made a bridge out of maple today, now that I done it I would do it a little differently. Mind you that is the difference of thinking how to do something and putting the thought into practice. 'Might have been better if I did it this way'

So I have the bridge made up, the neck joint ready to go. Need to do the tuner holes, round off some edges and do some finish sanding (ironic considering the wood). And the fretboard markers, almost forgot of them. Then it is a question of how to finish it. Leave it all blond, stain while the wood is bare, put a coat on it and see what happens next? I think I have to figure out which direction I am going as the markers are going to have to contrast the fretboard.

If I stain the body the fretboard will have to be stained black also. It would just look like any old guitar (nothing really wrong with that). There is enough contrast between the maple and the spruce, wonder if the finish will change that? First let's get the little things that need to be done out of the way.
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  #29  
Old 01-25-2018, 09:26 AM
Truckjohn Truckjohn is offline
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If the goal is a quick, dirty, cheap build to demonstrate that building an instrument really isn't that bad - wipe on some poly and off you go.

If the goal is to make it look more "official".... Then I would consider some sort of brown stain on the body/neck and something black on the fretboard... And then the finish of your choice over this.
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  #30  
Old 01-25-2018, 10:46 AM
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I went with black side dots so it looks like the color will remain like it is.

Decided to go with a maple bridge. Also put a radius on the fretboard with sandpaper and a block with a 12" radius cut in it. I don't think this will be much of a classical player.



Roughed out the bridge with the hacksaw.



Cleaned up the dimensions with my handy dandy big file. I like it a lot. I marked out the saddle slot and slit inside the lines to give me somewhere to start with. Then started to cut at an angle and picking out bits of wood. This is going nowhere



That is better. The saw has a wide kerf for normal guitar making jobs but it was still too narrow to make the saddle slot. I angled the saw and cut more into the slot width, I also found that pushing fairly slow and making sure the teeth were level I could get a pretty clean surface on the bottom.



I have a needle file I use to do frets with. One narrow edge is filed flat so the teeth do not cut the fretboard when shaping the frets. I used that side down while I worked on the sides of the slot.



I used the razor saw to cut the tie block and the center section out. I probably would use it for doing the saddle slot if I ever did it this way again (not bloody likely).



The center section cut out, filed a small radius in the back of the tieblock. Used the bought bridge to space the holes for the strings.



The holes angle up so I had to tilt the bridge when drilling with the drill press. I used a saddle to angle the top out and one at the bottom so the clamp would be giving pressure on the top and bottom.No doing this freehand if you want the strings to end up in the right place, sorry.

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