Body cavity diagram

I grabbed the bottoms of some old Jackson pickups and mounted them into the pickup cavities so I could have floating pickups and get rid of the pup rings, how should I fill the screw holes and make it match the body?

Pegs installed fingerboard epoxied on Frets leveled and dressed Bridge routed and installed Electronics cavity routed Back plate cut from 1/16” stainless Body sanded with pore filler
I had a big screw-up drilling the through holes for the strings. I started with a 3/32” bit and managed to break two of those off in the holes. I went to a machine shop hoping they could run them through with an edm hole popper but the neck was too big for their machine. They gave me a hardened pin to try and hammer the bits out. No luck there. I ended up using a 1/8” Rescue bit that was able to bore through the drill bit pieces and the surrounding aluminum in about 2hrs. It was definitely worth the high price tag imo.
Lesson learned. Small bits generate more heat from friction so it’s better to just start with a larger bit than to drill a pilot and step up. I might even use an ice pack to keep the block cool next time.
At this point I’m mostly waiting on the Creamery pickups before I can move on. I might finish the nut and string it up in the meantime.

The MIJ parts bass, the neck is a Jazz from the 80’s and the body from 2010, already had been modded with an extra hole in the pickguard. Had the pre sitting around since I traded the 4HH away. Result? The Lollar Precision 90 LOVES the pre. No mud, just full rich bass, not super loud or harsh. Yes it all fit in the cavity as is, the mini pots were perfect.

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Xue Feng
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https://preview.redd.it/inye2mb6lc1d1.jpg?width=606&format=pjpg&auto=webp&s=91a7161a35c1824c81442d04ca1efb17d2cbda20
Though the modern medicine has limited knowledge of human bodies, what we have known is enough for us to admire the excellent human body structure and functions. Each system and organ in the human body is designed by the Greatest Creator. Even those trivial body parts have great functions. For example, there are several types of hairs on human bodies with distinct forms and functions. The head hair is designed to protect and beautify the head. It can grow long. According to the Bible, “But if a woman has long hair, it is a glory to her: for her hair is given her for a covering.” The eyebrows can divert sweat and rain, preventing them into the eyes. That’s why they are lined above the two eyes. Eyelashes can prevent the dust and other things from entering the eyes. That’s why they are lined on the sides of the eyelids. Also they stand forward in a special curve because it wouldn’t hinder the eyesight or pierce into the eyes when closing the eyes. If the eyebrows and eyelashes are too long, they will hinder the eyesight. That’s why they wouldn’t grow as long as the hair or beards. The nasal hairs can filter the inhaled air. That’s why they grow inside the nostril and stand sideways and outwards. If they stand inwards, the other things will find it easy to come into the nostrils and difficult to go out. The armpit hairs can prevent the partial friction and help the sweat evaporate. Without the armpit hairs, we have to raise our arms. Otherwise the skin under the arm will become inflamed because of the friction and moist. Required by the function, the armpit hairs cannot grow as long as the head hairs, or as short as the eyebrows. Besides, they are soft and curving. If they are rigid and coarse, they will hurt the skin. And cilia grow on the intestinal epithelium. The cilia grow downward and vibrate together. The vibrating waves move downward from upward to help move down the intestinal contents. Cilia also grow on the airway and bronchus epithelium. However, they grow and vibrate in the opposite direction as those on the intestinal epithelium. Only in this way can they move the sputum upward to the throat and spit them. If they grow downward, the airway and bronchus would get stuck by the sputum and the humans would die from it.
Now I wish to take two simple reflections of human bodies as an example. When foreign matters enter the nostrils or airways, they will arouse two protective reflections, sneeze or cough, which is designed to repel the foreign matters. But due to different situation, these two reflections differ in their approaches. The foreign matters in the nostrils are not urgent so the sneeze reflection can be prepared in a composed way. First, inhale slowly; open the mouth, and the soft place move upward to block the nostril. Then breathe in enough air through the mouth, and the pleural body contracts sharply to emit the air in the lungs quickly. When the emitting reaches its peak, the tongue rises abruptly to block the mouth to repel the air to go out swiftly through the nostrils. In this way the foreign matters in the nostrils are driven out. However, if the foreign matters enter the airway, it is an emergent situation. If the foreign matters are not driven out timely, the life will be put at risk. The inhaling is strictly forbidden because it will make the foreign matters go deeper and cause suffocation. So the cough doesn’t include the inhaling. Instead, the glottis closes immediately. At the same time, the pleural body contracts suddenly and adds the lung air pressure extremely. When the pressure is at its strongest point, the glottis opens suddenly and the lung air sends out explosively, compelling the foreign matters in the airway to the throat via the glottis. At this time, the soft place rises to block the nostrils. The foreign matters are spit out through the mouth. If the tongue and the soft place perform the same way as in the sneeze, the foreign matters emitted out of the airway will enter the nostrils, causing another trouble. In these two reflections, the body parts must cooperate closely. Any failure in the coordination will lead to the failure of the reflection, causing serious consequences. So these activities are not done freely. Instead, they are done as required by their functions and set procedures. These procedures are not learnt or practices. The program has been rooted in our brain nerve structure (nerve nucleus) when we are born. Otherwise, the babies will not survive.
The advanced computer science has made it possible to simulate these activities. However, the simulation requires 3 conditions: 1. Device simulating the inhale and exhaling of human mouth, nose, throat, pleural and the sensing device; 2. The central control equipment simulating nerves and body system (compute, input and output devices). The above two devices are hardware. And software is also needed, namely (3). A program composed in strict compliance with the requirements to control the performance and procedure of each link, and arrange them in perfect coordination. All the three conditions are imperative. Otherwise the reflections can’t be realized. The program itself is not a substance structure. Instead, it is a smart use and spiritual result. There will be no such a thing as the program without the smart use. So we have to ask, the program is composed by the humans and stored in the computer, how about the control program in the human brain. Is it also composed by someone and stored in the human brain? Sneeze and cough are the simplest examples. There are numerous automatically controlled physical, bio-chemical and pathological human body activities, which are even more sophisticated than reflections of cough. Even today, some of them remain mysteries to us. So how are these sophisticated control programs composed? And where do they come from?
Now let’s have a look at the sensory organs on human bodies. Why do we have two ears? The reason is that one ear is not able to identify the direction. With the ears lying on two sides of the head, the sound reaches the ears in sequence of time. Based on the slight receiving time difference, the brain can judge where the sound comes from. The auricle is the most outward component of the ear. It can introduce the sound into the external auditory canal. Within the auricle there is a thin layer of cartilage helping to retain the form of auricle, giving it wonderful elasticity and protecting it from the clashes. Without the cartilage, the auricle is just two useless pieces of skin hanging on the head side. If the thin bone is inside the auricle, it will break easily even if when you are sleeping on your side, damaging the auricle. There is fuzz on the outer segment of the external auditory canal preventing the sand and dust. The inner segment secretes cerumen to prevent insects. When foreign matters enter the external auditory canal, it will trigger head shaking, instead of sneeze or cough, to get the matters out. Because the external auditory canal is a blind passage, it is impossible to repel the foreign matters with air.
Why don’t the foreign matters in the nostrils arouse the head-shaking reflection to repel them? That’s because the nostrils of humans almost lie in the middle of the head. The shaking is not able to produce enough centrifugal force. Besides, the human nostrils face downward and it is improper to repel the foreign matters by shaking the head. The sound is produced by the mechanical vibration of objects and is transmitted by the air fluctuation, or the sound waves. The human ears are actually working like a precise mechanical vibration monitor. In the inner ear there are a number of keyboards with different sizes, producing nerve impulses produced by echoing with corresponding frequencies. The brain, in accordance with the features of these impulses, identifies the strength, tunes and timbre of the sounds.
We must note though there are many sensory organs in human bodies, only the inner ear is protected by the most solid and firm bones. In fact, it lies in the cave part of the temporal bone. Of all the sensory organs, only the ears monitor the mechanical vibration, which needs a relatively fixed position. Otherwise, it is not able to monitor the sound. If the inner ear lies in the soft tissues, when the sound wave arrives, the inner ear will vibrate with it. Thus it can hear nothing. Now the inner ear lies in the firm bone and it can’t sense the air vibration. So it is imperative to reduce the density waves to the mechanical vibrations before sending them to the inner ear. And there is such a reduction device at the middle bottom of the external auditory canal, which is called the eardrum. The eardrum has enough space to receive the air pressure. It is thin enough to vibrate when the sound wave arrives. Meanwhile, the eardrum is strong enough to push the transmission device. The long handle of the middle ear cartilage is attached to its inner side, the tensile force of which makes the eardrum sink inside slightly to maintain certain tension. This allows the eardrum to accurately reduce the arriving sound waves into the mechanical vibrations. No matter what the temperature is, the vibration function is not impacted. After the sound waves are reduced into the mechanical vibration, some rigid objects are needed to transmit the vibration to the inner ear. Of all body tissues, the most rigid objects are the bones. However, the bones are heavy in general and covered by the soft tissues, which are not suitable for the audio vibration. However, in the tympanic cavity between the eardrum and the inner ear, there are three unique tiny bones with delicate forms measured in millimeters. They are almost completely exposed to the air in the tympanic cavity. These three tiny bones are connected by ligament and form a transmission chain in curve with excellent audio vibration function, able to transmit accurately the vibration of the eardrum to the inner ear. The transmission device can properly multiply the weak vibration and reduce the strong sound wave. All of these structures are the super designs required by the acoustics.
There are even smarter designs in the hearing organ. For example, to make the eardrum vibrate freely following the arriving sound waves, the two sides of the eardrums must be exposed to the air. As a result, there is a tympanic cavity full of air in the middle ear. If the cavity is filled by liquids, just as other cavities are, the eardrum is not able to vibrate because the liquids can’t contract. Besides, the cavity does not only need to be filled with air, but also needs to be connected to the outside world with a proper passage, to balance the static air pressure in the cavity with the outside air pressure. Otherwise, the air in the cavity will gradually be absorbed, causing the eardrum to sink excessively or damaging it. When the outside air pressure changes, (such as in mountain climbing, diving, the airplane takeoff or climate change), it will arouse uncomfortable feelings or lead to hearing malfunction. But the middle ear can’t be opened to the outside world directly, just like the external auditory canal or nostrils can. The reason is that the direct exposure will make the arriving waving sound reach the two sides of the eardrums at the same time via the external auditory canal and middle ear passage, counteracting the sound pressure. Thus the eardrums will not vibrate at all, unable to produce the hearing. So it is a difficult problem to connect the middle ear and the outside world. However, the human body, with a smart design, solves this problem. The middle ear is opened at the two sides in the upper rear of the pharynx via a half-opened passage (the so-called auditory tube). The auditory tube is locked in common times and only opened temporarily when taking the swallowing actions, balancing the air pressure in the middle ear shortly. After the swallowing action is over, the auditory tube is locked again. Apart from eating, human body would regularly take swallowing action unconsciously, even when he or she is sleeping. Thus the air pressure in the middle ear can be adjusted from time to time and avoid the hearing from being hindered. Besides, when swallowing, the swallowing segment and the soft palate will definitely rise, blocking the mouth and nostrils against the outside world. So on the moment when the ear and throat are opened shortly, though the air in the throat can enter the middle ear, the sound waves from the outside world are blocked against the middle ear. As a result, the hearing will not be interfered and can receive the outside sound and voice. Only the throat in the body can meet the special demand of the hearing organs. The throat is originally designed as part of the digestion and breathing system, it does not belong to sensory system. However, it can cooperate so smartly with the hearing organs. We have to admire the extremely delicate body-wise design.
The vestibule in the inner ear controls the balance of the body. In the vestibule there are 3 semicircular canals. When the body loses balance, the mutually-vertical semicircular canals produce the balance impulse, which triggers the corresponding reflection via the balance center in the medulla brain. Why are there 3 semicircular canals instead of 2 or 4? And why are they mutually vertical? The reason is apparent. Humans live in the 3-dimensional space. There are 3 mutually-vertical movement directions, namely, front and rear, left and right, upward and downward. So the 3 mutually-vertical semicircular canals can monitor the movements. The number less than 3 or more than 3 would be insufficient or redundant. We can see the delicate and smart structure and function, and the supreme wisdom in them. They can’t be the accidental results.
As the most important perception of human bodies, vision provides more information than that provided by all other perceptions. The vision is the perception of image and space and the visual organs must have the most precise and accurate structure completely different from other sensory organs. As a result, in the perspective of the embryo-genesis or neuro-anatomy, the main structure of the eyes is not just the common receptor. Instead, it is part of the cerebral cortex. The so-called optic nerves are completely different from other cerebrospinal nerves. In essence, the optic nerves are inner structure in the brain, transmitting the most sophisticated visual information. The eyes function like a precise camera. The retina composed of the photoreceptor cells is just like the films. The crystal, iris and the cornea works like the lens, diaphragm and the filter. However, the precision and automatic adjustment of the eyes is no match of any high-quality cameras. For example, the lens in modern cameras is made of special glass or hard plastics with fixed focal distance. When taking pictures for the landscapes with different distances, the lens position must be adjusted. Otherwise, the image will not be produced on the films. But this is an awkward approach. Imagine when the eyes are watching landscapes with different distances, the eyeballs have to protrude or recess alternatively, which looks ugly or damages the health and function of the eyes. However, the crystal in the eyes are transparent and elastic colloid, which can adjust automatically the focal distance in accordance with the distance of the objects to make sure all the objects can be imaged on the retina, without changing the position of the crystal. Such automatic adjustment function can’t be fulfilled by any camera.
If we observe the eyes in the perspective of modern TV technologies, the eyes are more like the television camera, but thousands of times more precise than the television cameras. The TV image is composed of dense pixels (the mixed dark or brilliant light spots). Till now, the best TV image only contains less than 1 million pixels. However, the human eyes can produce image containing 20 billion pixels. Only the eyes can see the details of objects. No matter how clear or accurate the image is, it is still a plan view image. Then how the eyes can provide the dimensional image is a key issue of providing the complete vision. But it is not an easy task at all to convert the flat view image into the dimensional one. For a long time, people have been puzzled by how the conversion is done. Of course, we later knew the smartness and delicacy of the human body shown here. The two eyes send the flat view images they receive into the same nerve center, which contrasts and analyzes the images and judges the distance of the objects based on the slight visual angle difference caused by the position difference of the two eyes. Thus the dimensional image is produced. That’s why people have to have 2 eyes to establish the complete vision. Based on such understanding, humans have invented the dimensional movies. But the above is only the external process of how vision is formed. People have little knowledge about how the visual center works inside. We have to admit that the mysteries of human body structure and functions are beyond the intelligence of mankind.
As a matter of fact, the distance judgment with two eyes is the triangulation technique which is precise and automatic. The accurate measurement needs two premises. First, the two eyes must focus on one object at the same time. Otherwise, there will be double vision, which means the one objects will be seen as two objects. As a result, the complete neuromuscular system is equipped on the outside of the eyeballs, making the eyeballs the most flexible and accurate organs. The ciliary muscle inside the eyeballs can adjust the conversion rate of the crystal at any time to focus on the object and form the clearest image. Second, the retina of the two eyes must be strictly symmetrical. Otherwise, the image contrast of the two eyes will become impossible. Furthermore, the images received by the two eyes must be transmitted at the same time to the same visual center for contrast and analysis. There are two visual nerves on the left and right side of the brain, supervising respectively the two sides of the vision field. The objects in the left of the vision field are reflected, via the eye pupil, on the retina of the right sides of the two eyeballs. The corresponding images in the two eyes, via the visual nerve, are sent to the visual center on the right side of the brain. The objects in the right of the vision field are reflected, via the eye pupil, on the retina of the left sides of the two eyeballs. The corresponding images in the two eyes, via the visual nerve, are sent to the visual center on the left side of the brain. The two visual nerves contrast the corresponding images coming from the eyes and produce the full-field dimensional images. The pairs of human parts are often symmetrical on the outside. Only the retinas are symmetrical in the same position. Namely, the left side is symmetrical to the left side and the right side symmetrical to the right side of the two retinas. That’s because the light rays come in directly. Otherwise, the visual centers can’t receive the corresponding images or get the coordinated vision. The structural symmetry of the retinas in the two eyes must be accurate to the utmost. Otherwise the images in the two eyes will not comply with each other and the ambiguity will occur. Besides, the corresponding images from the two eyes must be sent to the same visual center. Thus the optic nerves must have the corresponding special structure to realize the cross-transmission of the images. This is the unique “chiasma opticum” unique to the optic nerves. This function is not possessed by any other nervus cerebrospinalis because they don’t handle the information of images and space. If we use the computers and monitoring cameras to simulate the process of human vision, the input network of the computers has to have a similar chiasm. No other design can do it. Judging from the above, we can find all the human organs, structures and functions have shown the supreme wisdom. And these are the ways they should be.
Some people think that human body has some useless organs, such as the thymus gland, appendix, tonsil and coccyx, in order to prove the human structure is imperfect. Some people used to believe that these organs were not that useful. Instead, they tend to arouse diseases such as appendicitis and tonsillitis. If these organs are cut off, it will not have much impact on the human body. In the past, people used to classify spleens and other organs into the useless organs. There was a list of useless organs in the past which included over 100 organs. But the list was long not because these organs are useless but because people at the time were ignorant. As more we know about the organs, most of them have been deleted from the list and there are only a few still remain in the list. Some people think that these organs are the leftovers of human evolution, which are called the “waste back organs” and use them as one of the evidences of evolution theory. This is a complete misunderstanding. Till not we have understood there are no such things as the “obsolescent organs”. It is simply the lack of knowledge of these organs. Take the thymus gland as an example. In the past, people didn’t know its function. Now we have understood it is the warning device of the human body against the inner and outer infection sources. As a result, the thymus gland contributes a lot to the human health. Another example, if the coccyx fractures, it will cause serious functional disturbance. So the coccyx is also an imperative part of human body. Some people might say these organs can trigger diseases. Then all human organs can lead to diseases, even brain and heart are of no exceptions. Why don’t we say the brain and heart are useless? Some organs, though they are not as important as the heart and brain and wouldn’t endanger life immediately when eliminated, are also useful. Just like if the hands or feet are lost, though not fatal, the human body is handicapped.
After knowing the supreme and smart design of human structures and functions, you might want to know how they come into being. Who has designed and made such sophisticated and precise organs? We cannot avoid the question. Any truth-seeking person would admit that the extremely delicate organs and structures are not produced naturally or accidently. For instance, if someone gives you a top-class camera and tells you it is a natural one without designer or manufacturer; do you think his words are scientific and acceptable? The human body, which is even more delicate, accurate, flexible and practical, must have a supremely wise and capable creator behind it.
On a spring Sunday morning in 1954, I saw a young stranger sitting in the chamber of a Church. When we started to talk, I knew that he was a student at Peking Union Medical College. He said to me, “Since I studied anatomy and physiology, I have felt the human body is really a wonder. It is not possible to understand it unless we interpret the wonder with a God.” He came to the church to seek an answer. The wonder of this young man is not the only example. I remember that when I was studying anatomy and physiology in school, some students surrounded our physiology teacher and kept asking him questions. Finally, the teacher, annoyed by so many questions, told us, “Please stop the questions because they will lead to religion in the end.” Because of the special political background at the time, the teacher’s warning silenced all the students. But his warning impressed me deeply and remained in my memory till today. My thought at that time was that the teacher was right because all the things were created by the God. Though he was not a Christian, he had to admit the truth and the further probe into the human body mysteries (part of the Universe mysteries) would definitely lead to the existence of the God (religion) in the end. Otherwise, it would be impossible to explain the wonders of the human body. The Bible says, “For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, even his eternal power and Godhead; so that they are without excuse.”(1:20 Romans 1) Was the teacher demonstrating his scientific spirit? No. The scientific spirit means the truth and boldly pursuit of the truth without avoiding any controversy. The teacher knew very clearly that one more step forward would lead to the God but he dared not move onto the path towards the truth. Instead, he asked his students to stop there. It has shown that many people refuse to admit the existence of God not because they don’t have the scientific spirit but because of the social pressure, individual consideration for their interest and prospect, just as what the teacher was doing at that time. Nevertheless, the existence of the God would not change. And we cannot live in such considerations for the reality forever. One day in the future, when we have to face the ultimate choice, we will have to face the supreme master who has created the Universe and the human beings. The Bible says, “And as it is appointed unto men once to die, but after this the judgment.” If we don’t accept the immoral God now, we have no excuse when it comes to the day.
When we talk about the origin of all things in the Universe, some young people often ask, “You have said the humans are created by the God, then who has created the God?” The analogizing logics seem to be reasonable. But it is not true. Because the God is the creator instead of the created, you can’t link these together. The table is made by the carpenter. But you cannot say the carpenter and the table have the same origin. Human benings’ understand of the God is only limited to the enlightenment from the God to the humans. Otherwise, humans cannot understand the mystery of God’s nature. The God says, “I am Alpha and Omega, the beginning and the ending, saith the Lord, which is, and which was, and which is to come, the Almighty.” (Exodus 3:14 and Revelation 1:8). For the God, there is only the eternality, and there is no time, beginning or ending.
Even in the scientific field, too many analogizing questions won’t be tolerated. One scholar was talking about the belief in the God with his students. One student asked suddenly and proudly, “Where does the Universe come from?” The scholar answers, “The Universe is created by the God.” The student continued to ask, “Who has created the God?” The scholar answered, “The God is Alpha and Omega and I am not created.” The student said, “This is not scientific at all.” The scholar then asked the student, “Where does the Earth come from?” The student answered, “The Earth comes from the Sun.” The scholar continued to ask, “Where does the Sun come from?” The student answered, “The Sun comes from the Galaxy.” The scholar asked again, “Where does the Galaxy come from?” The student hesitated and answered, “The Galaxy comes from the nature.” The scholar continued to ask, “Where does the nature come from?” The student couldn’t answer this question and said in anger, “The nature is the nature and comes naturally.” The scholar then laughed, “This is not scientific at all.” So we can conclude that the “scientific” answers are not scientific. Another example is that the sciences tell people that substances are composed of the molecules. Then what are the molecules composed of? The molecules are composed of the atoms. But what are the atoms composed of? They are composed of the electrons, protons and neutrons. Then what are the electrons, protons and neutrons composed of? Till now, we cannot find an answer to this question. The atomic physicists are now working hard to find the “elementary particle”. They are called “basic particles” because the scientists don’t expect the substances to be divided limitlessly. So they believe that one day they will find the ultimate component, the “elementary particle”. Of course, the scientists will not ask such question of “what is something composed of?” This is the extremity and everything ends here. The materialists claim that the Universe is limitless and that the materials are eternal and can be divided limitlessly, etc. They are simply the groundless conclusion of the philosophers. And there is an extremity in their logics, the materials. They say that the materials are Alpha and Omega but can’t tell where the materials come from. Now let’s have a look at the math. All numbers come from 1, followed by 2, 3…. You can’t ask what the 1 is because 1 is 1, and not other numbers. It means that 1 is the origin of all numbers. The Greatest Creator has created all things and the Greatest Creator is the origin of them. It will be meaningless to ask where the Greatest Creator comes from.

Built my first strat style guitar over the semester and took it to a shop to get my nut filed and finish the setup but when the strings were on the action of the neck was causing the 22nd fret to catch and make it mostly unplayable. Truss rod adjustments don’t seem to change the action at all. That’s the main problem; otherwise the frets need to be hammered in more and glued down into their slots. I believe i installed the truss rod incorrectly, meaning it should be fixable. (I used some type of caulk to secure it at a few points in the cavity, my research now suggested a full glue up to join the neck and rod.)However, the guy at the shop thinks it would be more trouble than it would cost and is advising me to build a new neck or buy a premade one to salvage the body, which works fine. So my questions are:
Any way around the truss rod issue? Could I lower the neck pocket depth towards the back to raise the neck angle? Put some shims in between the body and the neck? Any way I could pull the truss rod out and reinstall it without taking the fretboard out?