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  #16  
Old 03-05-2019, 11:07 AM
Neil K Walk Neil K Walk is offline
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*sigh* It's only a "student grade" top...

I tore out some grains pretty bad so that the top will likely wind up being less than .1" thick and (judging by the tap tone) a little too floppy. I'm trying to understand what I did wrong, and so far I'm thinking:

1: I need to stabilize/reinforce the wood grains with a 1lb "spit" coat of shellac,

2: I need to set my blade depth - and cutting angle - *very* shallow,

3: I need to orient my stroke ~45 degrees from the wood grain but with the plane itself turned at angle (so that the cut is head-on) in "snow plow" fashion.

4: I need my blades to be even sharper so that they don't "dig in" to the grain

5: I need to relax the action of my stroke so that I ease into it, not jam into it.

I will say that I think I prefer using the one-handed block plain over the two-handed jack and smoothing planes.





It was a $20 lesson but I've continued on after applying shellac and getting successfully reacquainted with the circle cutter for the rosette, so it's not a complete loss. I've ordered a replacement top and desire to jump back into it while the lessons are still fresh in my memory.
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  #17  
Old 02-24-2020, 08:11 AM
Neil K Walk Neil K Walk is offline
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Apologies for the long-delayed bump to this thread. I had to put this aside so that I could focus on others things such as a full DIY bathroom remodel, the completion of the body of my second build (which has been fraught with mistakes that I'm noting to avoid this time around,) and a long unresolved family matter (actually several family matters) that has been nagging at me for some time now.

Fortunately, most of these distractions are more manageable now. I don't want to bite off more than I can chew though so this build is going to slowly moved back to the front burner. Given the time of year and my continued inability to stabilize the RH of my workshop I will not be picking things back up until April. Instead, I'm focusing on "spring cleaning" in the workshop and building jigs, sharpening my blades and truing . I've acquired plans for a Fox Bender.

Looking ahead, I'm also making several notes of mistakes to avoid and procedures to read up on:

1: I need to have a better understanding of deflection testing.

2: I need to install the end wedge BEFORE closing the box.

3: I need to remember to true up the sides BEFORE routing my binding channels. Things got very ugly with build #2 and quite frankly there were times when I should have quit while I was ahead.

4: body binding: I need to keep it simple; no purfling on the back, just binding. That extra shelf for the purfling inside the binding is what got out of hand.

I'm sure other things will come to mind but I also need to confess that this will also essentially be a partly serviced kit.
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  #18  
Old 03-26-2020, 02:30 PM
Neil K Walk Neil K Walk is offline
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The RH has stayed above 35% in my basement workshop so I am resuming this build. Because my wife is working from home due to the current pandemic I am doing all the noisy/dusty work in the garage. I like having the extra light. Yesterday I worked on installing a decorative strip in the back.

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  #19  
Old 03-26-2020, 07:17 PM
redir redir is offline
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Quote:
Originally Posted by Neil K Walk View Post
I got the seam to the point where it passed the candling test and joined the top last night. Now Iím setting my mind toward the next steps.

Iíve plotted out where the rosette will go (a herringbone rosette from Stewmac; dimensions are available on their website) and using a compass drew in the bounding lines. One side of the plates was smooth so that face will be the one I inlay the rosette on; I will reduce thickness on the other - and that will be the next step.

Along the way I plan on checking the stiffness using a deflection jig. I know there are no set numbers to look for but I plan to err on the side of caution - unlike last time where TBH I got carried away.
I use a standard red brick placed on the bridge patch with the measuring device right over the center of the X-Brace to measure deflection. The top is trimmed perfectly rectangular and uniformly thinned and extend only 1cm past the guitar body tracing at the widest and longest spots, the lower bout and the head and heel block.

Most bricks probably weigh close to the same. If you want to use that method I can share some data. For a vintage Martin 000 sound I have found a deflection under those specs mentioned of .3 to be perfect.
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  #20  
Old 03-26-2020, 11:09 PM
cobalt60 cobalt60 is offline
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Quote:
Originally Posted by Neil K Walk View Post
The RH has stayed above 35% in my basement workshop so I am resuming this build. Because my wife is working from home due to the current pandemic I am doing all the noisy/dusty work in the garage. I like having the extra light. Yesterday I worked on installing a decorative strip in the back.


Wondering your thinking on:

-- Why shellac in the glue surface?
-- Why cyano for this particular joint, instead of yellow glue?
-- Why bother caul clamping if you're also using accelerated CA?
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  #21  
Old 03-27-2020, 05:46 AM
packocrayons packocrayons is offline
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Quote:
Originally Posted by Neil K Walk View Post
*sigh* It's only a "student grade" top...

I tore out some grains pretty bad so that the top will likely wind up being less than .1" thick and (judging by the tap tone) a little too floppy. I'm trying to understand what I did wrong, and so far I'm thinking:

1: I need to stabilize/reinforce the wood grains with a 1lb "spit" coat of shellac,

2: I need to set my blade depth - and cutting angle - *very* shallow,

3: I need to orient my stroke ~45 degrees from the wood grain but with the plane itself turned at angle (so that the cut is head-on) in "snow plow" fashion.

4: I need my blades to be even sharper so that they don't "dig in" to the grain

5: I need to relax the action of my stroke so that I ease into it, not jam into it.

I will say that I think I prefer using the one-handed block plain over the two-handed jack and smoothing planes.





It was a $20 lesson but I've continued on after applying shellac and getting successfully reacquainted with the circle cutter for the rosette, so it's not a complete loss. I've ordered a replacement top and desire to jump back into it while the lessons are still fresh in my memory.
Looks like you're using a low angle (bevel up) block plane. Generally, for things like this I do exactly the opposite. I take a stanley no5 with a toothed blade (File 3-4 teeth in with a triangular file), sharpen it, then lightly back bevel the flat side of the blade, to increase the cutting angle even more. You want to be approaching a scraper plane.
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  #22  
Old 03-27-2020, 07:37 AM
Neil K Walk Neil K Walk is offline
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Thanks for the questions!

Quote:
Originally Posted by cobalt60 View Post
Wondering your thinking on:

-- Why shellac in the glue surface?
For certain types of wood (spruce, cedar, certain other light colored hard woods like maple and sycamore) it's necessary to seal the end grain and the open pores so that the CA glue doesn't seep into the wood. Later on when it comes time to apply the finish the CA will react with it and has been known to produce a "day glow" effect. I don't know if walnut is one of those woods but I felt that since it has open pores it was better safe than sorry. I know that maple (what the back strip is made of) certainly is so I made sure to give it a quick coat - as an afterthought.

Quote:
Originally Posted by cobalt60 View Post
-- Why cyano for this particular joint, instead of yellow glue?
I was considering yellow glue (Titebond I) but wasn't patient enough to wait for it to fully cure. Titebond 1 sets in about an hour but they say not to stress the joint for at least 12. Given that this is a decorative inlay and not a structural joint I decided that thin CA was a better choice. Also, if there were any gaps I wanted them to remain clear of yellow glue residue so that I can fill them with a mixture of thin CA and walnut dust later on.

Quote:
Originally Posted by cobalt60 View Post
-- Why bother caul clamping if you're also using accelerated CA?
I admit it, it was overkill. I was using the caul to apply uniform pressure and decided to clamp it briefly so that I could walk away and sharpen my scraper. I didn't have it clamped very long at all; barely 15 minutes. I'm just glad it didn't get glued down to the center strip!
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  #23  
Old 03-27-2020, 07:55 AM
Neil K Walk Neil K Walk is offline
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Quote:
Originally Posted by packocrayons View Post
Looks like you're using a low angle (bevel up) block plane. Generally, for things like this I do exactly the opposite. I take a stanley no5 with a toothed blade (File 3-4 teeth in with a triangular file), sharpen it, then lightly back bevel the flat side of the blade, to increase the cutting angle even more. You want to be approaching a scraper plane.
Thanks! My main plane for this job was actually something pretty similar. A few years ago I saw a 14" No. 5 from Buck Brothers at Home Depot for about $35 and jumped on it. I've tried putting notches in a blade but I have to admit I don't understand why you would want ridges on the surface. I can only assume it's meant to reduce tear-out.

Since chewing up this top with the little No. 9 here I decided to put a lot of effort into truing the sole and sharpened several blades for the No. 5. It still bit hard into the walnut and took out a couple of chunks so I've still got some learning to do. Fortunately at .13" the walnut back plate is still plenty thick but I've moved on to using the scraper to whittle away at the last 1/32"-1/64".
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  #24  
Old 03-27-2020, 07:59 AM
Neil K Walk Neil K Walk is offline
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Quote:
Originally Posted by redir View Post
I use a standard red brick placed on the bridge patch with the measuring device right over the center of the X-Brace to measure deflection. The top is trimmed perfectly rectangular and uniformly thinned and extend only 1cm past the guitar body tracing at the widest and longest spots, the lower bout and the head and heel block.

Most bricks probably weigh close to the same. If you want to use that method I can share some data. For a vintage Martin 000 sound I have found a deflection under those specs mentioned of .3 to be perfect.
Thanks! I kind of got the methodology with using a brick and measuring at where the X brace intersection but found precious little on what actual distances I was looking for. This guitar will have 1/4" bracing so I'm thinking that less than .3 would be safer.
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  #25  
Old 03-27-2020, 07:59 AM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by Neil K Walk View Post
I tore out some grains pretty bad so that the top will likely wind up being less than .1" thick and (judging by the tap tone) a little too floppy.
You can counter that to some extent by leaving the braces a little taller, a little less scalloped, if scalloping.


Quote:
I'm trying to understand what I did wrong, and so far I'm thinking:

1: I need to stabilize/reinforce the wood grains with a 1lb "spit" coat of shellac,
You don't. That isn't necessary with soft woods like spruce, cedar, redwood...

Quote:
2: I need to set my blade depth - and cutting angle - *very* shallow,

Again, soft woods like spruce, cedar ... are very forgiving and easy to plane and can successfully be planed with high or low cutting angles.

Quote:
3: I need to orient my stroke ~45 degrees from the wood grain but with the plane itself turned at angle (so that the cut is head-on) in "snow plow" fashion.
Different people have different approaches and techniques to planing. I like to plane in the direction of the grain but with the plane angled a little to create a more shearing cut.


Quote:
4: I need my blades to be even sharper so that they don't "dig in" to the grain
Wood, generally, has a preferred grain direction. To plane those woods with minimal tear-out, one planes "with" the grain. If one planes "against" the grain, the plane will "dig in" and tear the wood. Part of being successful with a hand plane is to identify the grain direction and plane in the appropriate direction. A bookmatched piece of wood will have the planing/grain direction on one half in one direction and in the other half in the opposite direction.

Some species and pieces of wood have a grain direction that change along the length of the piece. Those can be dealt with by changing the direction of planing, by using a different bedding angle of the plane iron and/or different bevel angle and by closing the throat of the plane to near zero. A toothed plane can also be helpful for bulk removal.

While having a sharp plane blade is necessary to do good work, it isn't sufficient. One must also "read" the wood and plane accordingly.


Quote:
5: I need to relax the action of my stroke so that I ease into it, not jam into it.
In my experience, it is easier to do surfacing and thickness planing while the wood is still rectangular. It is easier to clamp and reduces the amount of edge that the plane blade "bumps" into.

Quote:
I will say that I think I prefer using the one-handed block plain over the two-handed jack and smoothing planes.
I'd find it very difficult, ergonomically, to use such a small plane for large wood removal.


It sounds like the issues you are having are largely about tool technique. I highly recommend you take a look at robcosman.com for information about sharpening, setup and use of hand planes. In my experience, he is an excellent teacher and really does know his stuff.
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  #26  
Old 03-27-2020, 08:06 AM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by packocrayons View Post
You want to be approaching a scraper plane.
Soft woods like spruce, cedar and redwood don't scrape very well: they are too soft. The best result will not be by approaching a scraper plane. If you've ever tried a scraper plane on those woods, you'll see it does more tearing than planing and leaves a pretty rough surface.

A well-sharpened, well setup plane - bevel up or bevel down - can leave a finished surface off the plane.
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  #27  
Old 03-27-2020, 08:09 AM
Neil K Walk Neil K Walk is offline
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Thanks, Charles! As you said, it's all about technique. As I was working with the walnut I found that your technique of following the grain but with the tool turned at an angle provided better results. I'm still having trouble with having the barest amount of blade to present past the surface of the sole - and at a level lateral angle - but at least I can continue to practice on this top.

PS: the second top I ordered is only wide enough for a 00. While disappointing, this is not a complete loss. I will still join the halves and work with it, though I'm mostly tooled up for a 000. I want to continue to explore working with domestic tone woods so maybe #4 could be a cherry/sitka 00?
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  #28  
Old 03-27-2020, 08:15 AM
charles Tauber charles Tauber is offline
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When I first starting making guitars, I was taught to inlay the back strip much as you have done, by running a router along a straight edge. However, a "trick" that I was taught was instead of using the flat side of the router/Dremel base against the straight edge fence, use the round side.

By affixing pieces of tape to the round side of the router base to form a progressively thicker layer of tape, one creates a base that has a spiral edge to it rather an a circular one. As one rotates the router against the fence, the cutter is offset slightly to produce a wider cut. One can then "dial in" the width of the cut using a single cutter without having to reposition the straight edge fence, or custom fit the back strip to the width of the slot.

The technique is not meant to produce, say a 1/2" wide slot using a 3/8" cutter, but works quite well for small adjustments in width.


In more recent years, I've seen no reason to inlay the back strip. Instead, I simply sandwich it between the two halves of the back at the time the centre seam in glued together. In my experience, there is no practical advantage or disadvantage to inlaying vs. sandwiching the back strip, but sandwiching it is much less work.
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  #29  
Old 03-27-2020, 08:18 AM
packocrayons packocrayons is offline
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Quote:
Originally Posted by charles Tauber View Post
Soft woods like spruce, cedar and redwood don't scrape very well: they are too soft. The best result will not be by approaching a scraper plane. If you've ever tried a scraper plane on those woods, you'll see it does more tearing than planing and leaves a pretty rough surface.

A well-sharpened, well setup plane - bevel up or bevel down - can leave a finished surface off the plane.
I've found when dealing with a bit of runout (and planing into the runout), a higher angle plane tears out less. Scraper plane may have been an exaggeration.

Of course, sharp is the most important
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  #30  
Old 03-27-2020, 08:30 AM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by Neil K Walk View Post
I'm still having trouble with having the barest amount of blade to present past the surface of the sole
A technique I learned from Rob Cosman that I like and use is as follows. Start with the blade retracted so that there is no blade extending past the sole (i.e. it won't cut). Use your index finger and thumb to rotate the depth adjustment wheel a small amount to advance the blade. Take a pass with the plane. If the blade still doesn't engage the wood surface, rotate the adjustment wheel a small amount more. Take another pass with the plane. Repeat until you get the depth of cut you want. With practice, this can be done without even changing your grip on the plane handle/tote and takes only a few seconds.



Quote:
- and at a level lateral angle
To some extent, that depends upon the design of the plane. Some mechanisms are easier to adjust than others.

You can gently run your finger over the protruding plane blade, sight down the sole of the plane - looking to see how equal the amount of protruding blade is across the width of the sole - and/or simply take a pass with the blade and examine the wood shaving. If the wood shaving isn't the width of the plane blade, or is thicker on one side than the other, the blade might be tilted.


Quote:
I want to continue to explore working with domestic tone woods so maybe #4 could be a cherry/sitka 00?
Good for you! I'm currently building a black walnut and Engelmann guitar, both domestic woods. There are many fine species of domestic woods that can make very nice guitars.
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