Inside First

[Guest]

 

Now that baby's got a nice back....great wood!

[Ken_N]

I worked on the belly some yesterday.  It has a flatter arch, so it didn't need much on the inside as far as recurve.  The outside didn't even need as much.  I don't cut the f holes in until I have it basically evened out.  It will, like the back, get final tuning after it is glued together, and the purfling is in.  

It started at 86 g. and the tap tones were, G, g, and high g on the guitar.  This happens a lot on bellies.  Do you find that?  Thinning it down, it is 74 g. and F#, f#, and high f#.  The ring tone on the back is f, so they are about the same.  I don't work to any numbers, frequency or weight, I just use them as a rough gauge that they are in the ball park.  If the back or belly was way above the other, it might need some arch changing; or a new piece of wood; not just thinning.  

I cut the f holes in, and checked it again,  F#, f#, and high d#.  So slashing the top drops the ring mode down a minor third; at least on this one.  Both back and belly need more thinning; the original Gofriller is VERY thin.   The back is thin around the edge too, but the belly is just thin in the bouts, and the edges are thicker.  I don't have anything lower than 2.5 or so yet.  I'd feel more comfortable about 1.6 thicknesses if I didn't know that they were there.  

Really, I would.  Wouldn't you?

 Once it is glued together, I don't know what thicknesses I end up with.

Well I just checked them.  The back has spots in the bouts at 1.8mm. the edges are about 2.5mm.  The thick point, just above the lower corner is about 5mm.   The belly is about 3.5 around the edges, 2-2.5 at the top, and 3 in the lower, and 3+ in the middle.  The wings are crazy thick still.

Now I have to do the final modeling, and rough tuning before gluing it up.

Yes, I will need to add a little wood on the treble side c bout.  I roughed it in wider than the ribs are there.  It ended up about 200mm, 160mm, and 100mm for the bouts.  Nice ratios, so that part is cool.

The cedar has a band about 15 mm wide with 10 grain lines.  The rest is probably double that.  Trees cut down around it?  

[Ken_N]

I worked on the f holes yesterday.  They are different on each side.  The back is two toned, the sides are brown and yellow, and the arches are offset to the treble side.  

Why wouldn't they be different?

It is 66 grams now.  The top two tap tones stayed the same, but the low one dropped from F# to low E.  I"ll get the linings cut back, and the neck set next.  I think I'll make a dummy fingerboard to set the elevation. 

 

[Ken_N]

I see that spell check changed dummy to yummy on the last post. Thanks guys.

I did use a wedge shaped to the fingerboard angle and thickness to set the neck.  I also had a strip of wood, pointed on the end, and marked at the stop length to set the projection.  It worked great.  It's all glued together; and I realized that I don't have and purfling.  I don't have strings for it, or the baroque guitar, so I have to buy some things.  I looked up nylon strings for the guitar, but they seem to have 1 or two wound strings.  I don't want wound strings on it; they shouldn't be needed.

The guitar is ready to glue together.  I haven't picked out fingerboard stock yet.  I thought of putting a single dark binding around it.  1 mm X 3 mm, just to cover the end grain and the seam. I should have something that I can make that, and the fingerboard out of.  

The back is just flat.  It is thinned towards the edges, but it has no bracing at all.  The original belly had two transverse braces, but the Eastern, or Atlantic Red Cedar from a 100 year old barn a friend tore down has a very weak E modulus, ERC is listed at .88!  So I decided to bolster the longitudinal strength with double X braces, and forgo the transverse bars.  

My wife claims that I don't do anything the normal way.

So here it is ready to start gluing the neck and back:

 

My blog post this morning had an old Motown song. I found a cover that is VERY GOOD.

People Get Ready (Live) - Curtis Mayfield (Sara Niemietz, W.G. Snuffy Walden, Jonathan Richards)

https://youtu.be/vaspHfblJ5E

 

[Ken_N]

Well the barn wood top is scrapped.  I filled the dark lines with wood patches, and then it started splitting where there were no dark lines.  A thin wedge off a wedge of Bear Claw Sitka cut into three pieces; the outside has worm holes; is going to work just fine.  I have the rosette in it now, and I'm just going to use two harmonic bars like the original.  I have no bracing at all on the back, and very small linings.  It shouldn't be long before it is all glued up, and ready for binding.

I noticed that the Aquilla set of strings has a wound low A.   That sounds like a bad idea.  Why would they do such a thing?  Other really cheap sets do too.  They are hard enough to find.  I guess that Gamut will be the choice.  At least they are a small, somewhat local company.  He does offer a set of mixed fret gut too.  I need to make more to spread the cost!  

I see that he says the thickest fret is at the top, and they get smaller.  I was figuring it out, and it seemed just the opposite.  I saw a video talking about flamenco guitars, and they said the strings are higher at the body, and lower at the nut, and low at the bridge.  I thought, "Cool, I did something right."  I'll know more when the belly is glued on.

 

 

 

[Ken_N]

I've been working on getting the violin and guitar ready for varnish.  The guitar is easier.  I want to get a seal coat on it before I glue on the mustache.  It is not the usual frilly thing.  By now you know I'm not one for doing things the usual way.

Yesterday the Bible verses started disappearing from my posts. First the newest ones, then the older ones.  All 3100+ They were still there online.  Today they are gone online as well.  Don't you LOVE it when you are censored, and they don't even tell you?  How nice.  My writing is still there, but the verses are all gone.  The title is there, and the verse numbers, but nothing else.  Some have a line or two spared.  

Yes, I am NOT politically correct. But don't we have the freedom of speech? 

EDIT :

AHHH.  All but two of the posts have been fixed.  Someone must have been playing around.

 

 

Edited July 31, 2020 by Ken_N

[Jim Bress]

Looks nice Ken.

[Ken_N]

Thanks Jim,

I still need to order strings and fret gut too.  That is by FAR the most expensive part of the project.  I've never even spent $200 on a piece of wood!  But I do want to find a new back and sides for a cello, so we'll see about that.

[Nick Allen]

1 hour ago, Ken_N said:

Thanks Jim,

I still need to order strings and fret gut too.  That is by FAR the most expensive part of the project.  I've never even spent $200 on a piece of wood!  But I do want to find a new back and sides for a cello, so we'll see about that.

That's the only thing that's been keeping me from making a cello for myself. So expensive. 

Nice guitar, though. I'd like to hear an audio sample when it's done. 

[Jim Bress]

34 minutes ago, Nick Allen said:

That's the only thing that's been keeping me from making a cello for myself. So expensive. 

Nice guitar, though. I'd like to hear an audio sample when it's done. 

Yup, I had to borrow from peter to pay paul...I sold violin wood to pay for my cello wood.  Tools are another story.  I buy the next cello specific tool as I'm getting ready to reach for it. When I'm all done I'll either have liked the experience and will plan for another, or have a tool sale.

[Nick Allen]

2 minutes ago, Jim Bress said:

Yup, I had to borrow from peter to pay paul...I sold violin wood to pay for my cello wood.  Tools are another story.  I buy the next cello specific tool as I'm getting ready to reach for it. When I'm all done I'll either have liked the experience and will plan for another, or have a tool sale.

There really aren't that many cello-specific tools. Most of the tools to make a violin are handy to craft a cello. I think the only ones that would be necessary would be the clamps for closing the box, which you can make diy the reamers and peg shapers, the latter you could jimmy together with a plane blade, and perhaps the corner block gouge, which could be simulated with normal gouges and a rasp or something. 

The f holes could be cut the hard way with just a drill bit and a knife.

Hogging the back to rough dimensions was a total pain in the ass, though. 

[Jim Bress]

42 minutes ago, Nick Allen said:

There really aren't that many cello-specific tools. Most of the tools to make a violin are handy to craft a cello. I think the only ones that would be necessary would be the clamps for closing the box, which you can make diy the reamers and peg shapers, the latter you could jimmy together with a plane blade, and perhaps the corner block gouge, which could be simulated with normal gouges and a rasp or something. 

The f holes could be cut the hard way with just a drill bit and a knife.

Hogging the back to rough dimensions was a total pain in the ass, though. 

Time vs. money...I've been averaging half work days (12 hours) since the new year.  Heck yesterday I didn't get off until today.   So, somethings I've purchased, like a tooth blade for ribs that I've made due without for violin but needed for cello ribs.  I also forked out the cash for a larger in-cannel gouge for blocks.  I didn't "need" it, but I wanted it and I'm happy I bought it.  Name brand, so if I don't think I'll ever use it again I'm confident I can flip it and get most of my money back.  Big money, is still down the road a bit because I'm slow.  Closing clamps, reamers, fittings etc.

[J.DiLisio]

The guitar looks great Ken.  Your binding and purfling turned out much cleaner than mine.  What's the scale length/how many frets will the neck have?

[Ken_N]

 

Thanks about the binding.  I used my homemade purfling cutters that actually cut, not just mark.  The long one is set up there for the binding width, and the purfling depth.  I like the screwed on cutter better, but the sliding adjustment is more flexible than shims.   The blade just falls out sometimes!  

It has a 540 scale, so it SHOULD  work in G.  Using the calculator on Gamut strings, a medium set should give  4.5/3.4/3.4/3.0/3.0 kgs per string. So about 75 pounds total. I have a plan for a Voboam guitar in E with a 635 scale, and it comes out to  4.5/3.4/3.3/2.9/2.9 with mediums.  So it seems that it will work fine in G at A 440.  

It has 10 frets.  That seemed to be standard for a while, then 11, then 12.  I have a plan for one that is only 9.  

 

 

 

[Ken_N]

I put have the strings on the guitar, and up to pitch; they are still stretching.  When I did it on Thursday, the bridge broke off.  Nice clean break, no wood.  It is a tiny bridge.  I used thin 195 high clarity.  Re-glued with 315.    Worked.

I need to figure out fret diameters that will work, and order some string.  I switched the tuners up on the first and last pairs so the strings aren't rubbing so much.  Seems better to me.

 

 

[Nick Allen]

I really like this guitar. It has a certain feel to the look that's usually hard to capture. 

Great work man! Keep it up. 

[Ken_N]

I found a student cello at a garage sale today, and posted it on pegbox. I'm not dead. The year has flown!  I have the walnut/Alaska cedar, and the Padauk/P.O. Cedar waiting for me to make pegs. I just finished a guitar based on an 1829 Stauffer from Austria. The guy who taught Martin. It has an adjustable neck, like Joseph Curtin talked about at a Michigan Violinmakers Assn. meeting back in January?  The turners are just regular tuners under the cover, and not tuners built on a brass back. You can buy those, with fancy engraving for $860 or so. Mine was about 1/50th of that.

The guitar is small, with a 620 scale length. It sounds really good. I changed the bracing. Not the locations, I just made them a little lower, very pointed, and shaped like a cycloid down to nothing at the ends, and not almost straight across, with a curve out to 5mm tall.

When I get the pegs done, I'll show some violins. I did varnish changes on some.

[Ken_N]

I finished a violin that I was never satisfied with the varnish about a year ago. It is inspirited by fall leaves. The varnish is fairly decent, for me at least! It doesn't look new, or from a factory. Revarnishing is harder than varnishing. Do it right the first time! I managed to get the ribs looking ok. I usually don't think about them. Really. That's true.

The fingerboard, pegs, and I think the tailpiece is made of Katalox. It was labeled as royal ebony. One side was black and the other cream. The cream is hard, but slightly less dense than the black. Maybe something like .78 to .9 sg. I don't really remember. It was hard enough for what it's doing.

I thought that these days with all the wood bans, getting around ebony would be good. The light wood gives a different look. It glows more than the photos show.

[Ken_N]

Boy, those photos certainly don't do that violin justice. 

I bought a 1/2 size cello at a garage sale for $5, and got the idea to finish up the cello I started a long time ago. The form is made, The belly is roughed out. The back needed to be replaced. It was a wedge. I sawed it in two; very badly! I tried to make it work, but gave up. 

I bought a large slab of Euro Sycamore a few years ago. It just barely fit in my Crosstrek. I made an arch top guitar out of a piece of it, when I thought that maybe it wasn't as thing as I really wanted. It is only about 29mm. I decided to use the rest of it, but it had bark on the lower part. I got most of it off, and it is about 26mm!  There was a bend going up lengthwise, and a bend going down widthwise.  

It didn't really take that long to get it roughed out. The other one was Big Leaf, and it was softer. It is 670 grams now, and the tap tone is D#. I found a nice cello build site Osnes violins. It isn't easy to find. It comes up on my Kindle easier than on my iMac. He goes B-C for bellies, and C-C# for backs. Or so. Good to know just for reference. If it sounds A, it might not work!

The back is smaller than the back, it will have tapered ribs. Someone, somewhere was saying a smaller back makes it more comfortable. I also heard that Cello ribs are thin, and important for the sound. Having them tapered may add some movement to them? I don't know. The form is made, the stock I had was only so big; so that is what it is. It is based on a Gagliano Cello back that was on one of those Calendars that were ads for a shop in California. There wasn't a shot of the belly. I drew it up a long time ago, and don't remember much about it! Being low, it is about 8.5 mm thick!

 

The Sitka belly is very dark. It's been sitting a while in the basement. I haven't put the f hole in yet. It is still too thick. It is 500 g now, and just below D#. It is only about 26mm high too. I didn't know that stock was so thin. 

It was a good deal though! If it ends up working, what would thicker stock do? Sometimes it would be nice just to buy the good stuff.

 

 

I think I'l do the ribs, now that the back and belly are pretty well roughed out. I can't do much more until the outline is finalized. 

I ordered a neck blank from International Violin. You can't find cello neck stock at lumber yards! It seems that laminated cello necks, in contrast to guitar necks, are frowned upon. Even built up heels. I mentioned that before, and no one though that it was a good idea. There seems to be way around a one piece neck. There ARE necks with peg box/scrolls grafted on; but that seems like a lot of work! 

I thought of making the neck adjustable, like the Stauffer guitar; but I don't know how THAT would be accepted. I know that Joseph Curtain said that he was working on the idea, or thought about it; but he is Joseph Curtain.

[Ken_N]

David Burgess offered to let me use his cello rib iron; so Friday I went over there. His iron gets hotter than mine ever gets. I think I'll get a Luthiers Bench one. It was a waste to buy the cheap one that I bought. 

I used Evan Smiths idea of using an iron to bend the bouts on the form. It made it easy to see where I had to bend the corners; because the ribs are tapered. The c bouts I just had to hold them at an angle; but that was easy to see. It didn't take long. The wide, 3 layer thick form made bending to shape, and glue up simple.

David had a Cello belly that was nearing completion on the outside on his large bench. It looked very clean. All edge work. Mine are mostly scrapers, and it does look different.

I have them all glued on now, and the front and back have plenty of stock around the outline. First I need to put linings in, then I can cut them out, and work more on the edge work/recurve, before gluing the box up.

 

[Ken_N]

The belly is almost ready to cut the purfling grooves. I'll wait to do that until I get the back ready. It is still thick around the edges. Before trimming the edges to 4.5-5mm, and cutting a platform for the purfling, leaving a 3.5mm wide edge that will be like a beaded edge when done; it was 400 grams. Now it is only 376 grams. The edges around the center bout area I haven't quite cleaned up yet. I need to switch scrapers. Everything will be gone over again after the purfling is in.

I have a Stewmac Dremel tool purfling tool.  l also have the small one they make for cutting the wood away for guitar bindings. I put tiny bindings on mine, but it is easier than scribing a line and planing or chiseling, or filing. I've done that too. It uses a 5/16 carbide bit. Using that bit with the purfling guide, I was able to make a nice platform for the purfling. I have OFTEN cut through the purfling blending in the edge work. I thought ahead this time.

The tool works really well for that.  You can see in the photo some spots where I need to blend what I have to what was cut with the bit. hopeful there will be solid purfling everywhere!

Checking the mode on Audacity, it has dropped to 132. Now they call it C, and not 135 C#, so I guess you have to  write down the numbers. I'll see what it goes to with the bar.

 

[Ken_N]

The back is pretty much done. The belly needs a bass bar. I want to test deflection. I have a go-bar deck made up. With it you can use wooden sticks, or fiberglass rods to hold things in place to glue. You can also test deflection. If the spacing is 23" or so, the 24" rods give 7 pounds of pressure. The back will be pushed by the force exerted by the sound post. About 1/2 of the pressure on the bridge. On a cello that's about 60 pounds; so half will be 30 pounds. 4 rods give 28 pounds. That's close enough. 

It moves .06"  I know the pressure will come from the inside pushing out; but I have no way of holding it solid to test it upside down. 

The belly without the bass bar moves .04" with just 7 pounds. It will be interesting to see what a bass bar does with that. The deflection on the belly will be the entire 60 pounds; so 8 or 9 rods! 

Now. If the belly moves .120" with the pressure on the bridge, and the back only allows .06" what happens? Does it force the top up .06"? I have no idea. Would it be ideal for the movement of 30 pounds on the back to be equal to 60 pounds on the belly?

I made a violin with a very stiff back, and a very light top with a very high arch. The arch may have moved up some, but not much. It is very easy to play. Does mismatching free the top more? Does making it even put more sound from the back into play. Does non of that have any correlation to anything?

People talk about things like that on guitar forums, but I have never seen anything about deflection here. People do test it. I understand not giving numbers. I wonder about theory; and then do whatever I want to do.

Like carve from the inside.

 

[uncle duke]

Is an almost 1/4" acceptable for down force movement for that belly with the rods on it? 

[Ken_N]

That's only 1/16 on the back. I only put 7pounds, 1 rod.on.The belly with no bass bar, just to see what the bass bar.has to accomplish. It moved .04 with that. Unfortunately, I didn't think to see how much it moved before cutting the f holes.

I don't type well with thumbs. I don't know how anyone for it!

[Ken_N]

I don't think I going to test the movement with the rods. I enraged to see what just the uncut bass bar did,  and with 4 rods it moved .02" about a third of the back. But one rod on the treble side moved it .02" more!  Besides that, I see tiny dimples that I don't need.

Who knew that cellos were like living, breathing animals?

Does anybody string  them up for a while, to see where they will go, high overstand and dummy fingerboard, and then set the projection? That's what I was planning to do,  it moves a lot more than violins do. Plane the neck if needed, and put a real board on when it gets to its happy place? 

I have a feeling it will want to find it.