HD28 Kit - First Build

[deadedith]

The top is domed and stays domed. The math is there; a long history of successful guitars is there; this is tried and proven over a long period and a variety of luthiers.

BTW, there are high-value guitars that DO have flat tops - such as the RTaylors.

It's good for you to keep researching; let me say though that the sponsors here are true professionals and they can help you narrow down your research.

[tippie53]

The top will act like a hydrometer . this is why it is important to use a case humidifier to keep the wood stable . Ona true flat top if the rh drops significantly the wood will shrink and it will pull in the top . Some flat tops are braced heavier to help avoid this and have a lower bridge height .
Martin does indeed have a small amount of doming in the top . The braces have a slight radius on them and the top will dome from the string load. This helps to a degree to help the sink if the top but all guitars can sink if the RH drops too far. This is something that is environmental and can change to each location . Here in PA we can see 90% RH in the summer and 15% in the winter .
That is why I use the 28 foot radius , I do flatten the neck area for the neck angle and allow the lower bout a slight dome . In essence I have a 3 facet top , the neck angle , the flat area from the angle to the bridge and the lower bout . These 3 separate areas also allow a designed stiffness to the top . The design allows for a thinner top and less mass. It is all part of the structural integrity . There are a number of famous builders that use this design feature and they make great guitars. Jon Garnon of My Favorite Guitars will be selling mine as soon so watch for them .
Ken uses a different design , it is not that one is better or worse than the other , it is a building system and you as a builder may even find one different from ours . It is like pickin a favorite color .

[tippie53]

I agree on the top kerfing that the angle is insignificant but it will make a difference on that neck block and I am sure you agree to that . The back kerfing is not a static angle and will change angles as you go around the rim . Here is where you can see an issue .
Key points to this is that it is what your building techniques are . The more of a radius , the more you may need to think about this . If you are using the radius disks this is a moot point .
I think Stew mac preaches using a 1 1/2 degree angle block on the top , and this isn't warranted .

[tippie53]

Totally agree . The stew mac system , doesn't bode well with martin kits . There is so much better information out there . Often Ken and I may not agree but we are trying to inform people the best we can . While ken and I often get in a spirited debate , this helps not just to get you thinking but to get us thinking as well .
Mixing and matching building techniques can often bring at best mediocre results . Keeping notes and building logs is the best way to see the cause effect relationship of your techniques . Ken and I will do our best to educate you to find a good result for you .
If you put 3 luthiers in a room and ask any questions I am sure you will get at least 4 opinions

[Rick S]

For some reason, the previous post double posted. So, I've deleted this post which is the duplicate.

[Rick S]

Totally agree . The stew mac system , doesn't bode well with martin kits . There is so much better information out there . Often Ken and I may not agree but we are trying to inform people the best we can . While ken and I often get in a spirited debate , this helps not just to get you thinking but to get us thinking as well .
Mixing and matching building techniques can often bring at best mediocre results . Keeping notes and building logs is the best way to see the cause effect relationship of your techniques . Ken and I will do our best to educate you to find a good result for you .
If you put 3 luthiers in a room and ask any questions I am sure you will get at least 4 opinions

John, I appreciate your advice and admire the manner in which you conduct yourself in this forum.

[deadedith]

I like your independent spirit, Rick!
It will be an expensive road for you, however, in terms of time and money. Time, because it is, as you will find out, very time-consuming to try a departure from tried and true; if the instrument ends up sounding good, you still have to be concerned about whether it was the variable you departed from that made the difference; and if you build another the same way to test it - well,"same" is difficult. Exact same wood, exactly same glue from the same batch and same age kept at exactly the same temperature; exactly same mass of bracing, kerfing, and other materials; same clamping pressures etc - well, it is difficult to build exact copies, changing only one variable, and then basing your final design on the results of one or two or three instruments. But unless you can control all that, you cannot say you have made a true, repeatable advance in your design.
And money - self-explanatory.
I know it's frustrating. But I have to ask myself: would it be THAT bad if, following traditional methods, I made a guitar that sounded and played as well as an Olson or Lowden? I have to ask: what is really my goal? If it is to express something that is uniquely me, there is a whole lot of expense, like above, that lies before me.
I'm just sayin'. We can seek for dead certainty in method and technique, seeking the absolute best, even before we begin to build; or we can seek wisdom, trusting somewhat in the equally bright (or brighter) people that have gone before us the past 150 years, and standing on their shoulders, modify tradition to the best that is in us.
I sincerely wish you the best of luck and hope that you find a rewarding path. We here don't know everything, but it is amazing to me HOW much the experienced guys DO know. They have not been cookie-cutters either, you know. :-)

[Rick S]

I like your independent spirit, Rick!
It will be an expensive road for you, however, in terms of time and money. Time, because it is, as you will find out, very time-consuming to try a departure from tried and true; if the instrument ends up sounding good, you still have to be concerned about whether it was the variable you departed from that made the difference; and if you build another the same way to test it - well,"same" is difficult. Exact same wood, exactly same glue from the same batch and same age kept at exactly the same temperature; exactly same mass of bracing, kerfing, and other materials; same clamping pressures etc - well, it is difficult to build exact copies, changing only one variable, and then basing your final design on the results of one or two or three instruments. But unless you can control all that, you cannot say you have made a true, repeatable advance in your design.
And money - self-explanatory.
I know it's frustrating. But I have to ask myself: would it be THAT bad if, following traditional methods, I made a guitar that sounded and played as well as an Olson or Lowden? I have to ask: what is really my goal? If it is to express something that is uniquely me, there is a whole lot of expense, like above, that lies before me.
I'm just sayin'. We can seek for dead certainty in method and technique, seeking the absolute best, even before we begin to build; or we can seek wisdom, trusting somewhat in the equally bright (or brighter) people that have gone before us the past 150 years, and standing on their shoulders, modify tradition to the best that is in us.
I sincerely wish you the best of luck and hope that you find a rewarding path. We here don't know everything, but it is amazing to me HOW much the experienced guys DO know. They have not been cookie-cutters either, you know. :-)

Thanks Dave. Don't get me wrong, I'm still a beginner and will be trying methods that other people have used. For this particular build, I bought the kit from John and I'm trying to do my best to do it his way which includes using the radiusing dishes. I'm considering taking one of John's classes to build my next guitar. I'm also still very interested in comparison of the two methods to see how each come to the same or similar results. I hope to get to that level of understanding of both methods during this first guitar. Long down the road, I do plan on finding my own way. But even at this stage, I try to keep an open mind.

[Rick S]

I've got some cleaning up to do but I think I've got the sound box pretty close to being ready for the top and back. I had to sand the top of the neck block so I had to spend some time making sure that the angle was still the complement of the angle on the neck. To document my process to this point, I took some measurements:

1) A line extended that follows the top edge of the neck block rises about a half inch above the opposite end as predicted by the neck angle.

2) When I use a straight edge to follow a line established by the top edge of the rims at the upper bout, there is an 1/8 inch rise at the tail block.

3) The neck block angle intersects a straight edge laid from side to side at the saddle location between a 1/16th and an 1/8 inch, let's say 3/32nds. I'm shooting for a 1/16th inch rise at the saddle location. C'mon doming effect, give me a little rise to get me back to 1/16th inch.

I've started gluing the bracing on my top this week. I have the main X brace, bridge reinforcement, and two braces at the top glued nicely in place. Still have the tone bars etc. Some of these require shaping so I'm going to take my time.

I haven't glued the back together yet. I need to stop by the lumber yard soon and pick up some wood to make a shooting board. I've bought a center piece to add between the back pieces so it should be fun trying to glue three pieces together evenly.

Closing the box is still a ways down the road. Maybe I can target to get that done during the holiday weekend.

[Rick S]

I got the shooting board made on Friday and sanded the joint edges of the back to get them ready to glue. Glued the back with the back strip on Saturday. I think it went ok. Even though I glued it on a gobar deck, there were a couple of places where the back strip was just a skosh below the back (on the outside). I sanded the back to eliminate these valleys.

I was surprised that Titebond started to set up as quickly as it did. I was using the method to use a 1/2 x 1/2 by 24" strip of wood underneath the joint to dry fit the pieces, apply the glue to the edges, remove the strip, and press down to form a tight joint. I don't know that this method was intended to use when installing a fairly narrow back strip. The back strip kept slipping out of position as I removed the 1/2 x 1/2 strip of wood. I eventually got it glued up but by the time I noticed the two areas areas where the strip was a skosh proud, the glue had already started to set up and the rods wouldn't push the strip down where it was perfectly flat.

I have some pictures to post. Maybe tomorrow.