401. How are magnet rods made?
Rod magnets are made very similar to the Alnico bar magnets with the exception of many rods approximately 6.5 to 11.5 inches long inserted into sand, removed and the molten magnet is poured in each cavity. Typical rod magnets used in pickups with the diameter of .187” start out at approximately .194” in diameter. For magnet diameters around .195” and slightly larger the raw magnet starts out at .210” in diameter and measured from the samples I have. The surface of the raw magnet is rough and pitted and one end is pointed similar to the shape of the molding tool and the other end is snapped off at the break-off gate used for pouring the molten magnet.

402. How are magnets magnetized?
After the magnets are molded they are heated to 935?C (± 5?) and cool in a magnetic field of proper shape and intensity. They are then held at 1290? C (± 5?) for the required time and held for one hour at 627? C (± 5?) and four hours at
550? C (± 5?). The magnetized leave the aging process magnetized and are de-magnetized so they can be finished or surface ground to the proper dimensions. We get all our Alnico magnets un-magnetized for special magnetizing and calibration. We have several magnetizers and custom built calibrators needed for special pickups and applications. I like using a DC Electromagnet and often use a permanent magnet to magnetize various pickups. We use an adjustable pole piece for various rod and bar magnets made from soft iron.

403. How are sintered rod magnets made?
Dry granules of Alnico material are compacted under high pressure in metal dies and is used for lower grade Alnico’s. Sintered Alnico magnets has a different chemical composition as compared to cast Alnico’s. Some of the various grades are:
Sintered Alnico 2 10 Al, 19 Ni, 13 Co, 3 Cu, Bal. Fe.
Sintered Alnico 5 8 Al, 14 Ni, 24 Co, 3 Cu, Bal. Fe.
Sintered Alnico 6 8 Al, 16 Ni, 24 Co, 3 Cu, 1 Ti, Bal. Fe.
Sintered Alnico 8 7 Al, 15 Ni, 35 Co, 4 Cu, 5 Ti, Bal. Fe.
Sintered Alnico 8 HC 7 Al, 14 Ni, 38 Co, 3 Cu, 8 Ti, Bal. Fe.
The sintered Alnico’s start as a 200 mesh powder and pressed to 30-35 tons per square inch at 1350? C (± 5?) and then heated to 935? C (± 50?) and cooled in a magnetic field of proper shape and intensity. They are then heated to 627? C (± 5?) for one hour and then 550? C (± 5?) for four hours. This process is for oriented grades only and ground to desired dimensions.

404. How can I fix the phase on other magnetic rod or bar magnets?
The polarity will need to be determined and re-magnetized opposite on pickups with rod magnets. Bar magnets used in humbucking style pickups can normally be removed from a pickup and flipped over 180?‘s and reinserted to reverse the phasing. Reversing the phasing in a pickup will only be noticed when being used with another pickup. Reversing the phase of humbuckers with 2, 3 or 4 conductor lead wire can easily be done by reversing the hot and ground wires. Sometimes there can be an internal phase problem when working with many different color combinations and hookup wires from different manufacturers.

405. How do I determine the magnetic polarity of my pickups?
There are several ways to determine the polarity of your pickups. In humbuckers made by Gibson and Seymour Duncan each bar magnet has a black line on the edge and that is used to represent the “North” polarity of that side of the magnet. The other unmarked side represents the “South” polarity. Normally on Gibson and Seymour Duncan pickups the adjustable side of a standard humbucker is the “South” polarity. On Fender pickups there are different polarities used for pickup position and era. Stratocaster pickups made after 1957 became “South” as standard magnetic polarity. Before 1957, Stratocasters had “North” polarity and early Broadcasters, No-Casters, Telecasters and Esquires often had both “North” and “South” magnet polarity. Fender started using RW/RP (reverse wind-reverse polarity) pickups in the neck position of their instruments. Such instruments were Duo-Sonic’s, Jazzmaster’s, Jaguar’s, Jazz Bass etc. Precision Bass pickups also had a RW/RP bobbin on one of the two split coils. Having a know polarity and if the magnet is South it will attract a North magnet and repel a South one. Remember the old theory: Like poles repel, unlike poles attract.
The easiest way is to purchase a Gauss meter from the R.B. Annis Company in Indianapolis, Indiana. I use the (-50-0-50+) hand meter. The -50 is the South side and the 50+ is the North side. I use it to determine the magnet polarity of a pickup and the magnetic gauss or strength at a given point. I will write about using an analog or digital meter for determining magnetic polarity and electrical phasing. Single coil pickups can be wound 4 ways and their combination with other pickups will give you many results and sometimes headaches.
Pickups can be wound:
TC-S: Top Coming South
TC-N: Top Coming North
TG-S: Top Going South
TG-N: Top Going North

406. How have the magnet pattern changed on the older to new pickups?
I’ve noticed that on earlier Fender pickups the polarity of the pickups often varied from North to South and North again. I’ve seen old Telecasters with a North bridge pickup and a South neck pickup. The older switching and wiring on the early Centralab 1452 Lever switch didn’t have both pickups on at the same time. Maybe that’s why Leo changed from the blend control on some of the earlier instruments. If the pickups were magnetized out of phase than the instrument would sound pretty thin when both pickups were used with the blend control. I’ve seen many early Stratocaster pickups made till around 1957 magnetized North. The pickups made from then until now have remained pretty much South. When the pickups are normally in the 2 & 4 position, either using a 3 position switch or a 5 position, the pickups are “In phase & parallel”. They are not out of phase in that position with standard pickup. During the 70’s I started reversing the polarity and winding direction on the middle pickup to give a quieter humbucking effect in the Strat 2 & 4 position. Gibson has always made the adjustable pole side of the humbuckers South as with the polarity of P-90 style pickups. During the building of the Gibson ES-355 (Stereo) guitars, the neck pickup had a North polarity because it was to be used with a stereo amplifier. When using a mono cord plugged halfway into the jack, you would have both pickups operative but out-of-phase with each other.

407. How should the magnets be positioned in a Gibson P-90?
The same polarity of each magnet should be positioned towards the center metal spacer. If both magnet poles are facing the center metal spacer are South, then the adjustable pole piece will also be South. If both are North, then the adjustable pole will also be North. If they are both opposite facing the metal spacer then there will be little or no magnetic field in the adjustable polepiece to pick up the string vibration.

408. How should you handle magnets and pickups?
Magnets and pickups need to be handled with extreme care and should be kept a safe distance apart. I would keep pickups approximately 3-4 inches apart. Magnets can be altered by the placement of other magnets or pickups in close proximity to them. I see pickups displayed in stores stacked on top of each other or on top of instructional video tapes. This improper way of displaying can alter the pickups efficiency, especially when being shipped as they are packed usually on top of each other and move back and forth in a box. The movement of two magnets next to each other can diminish the alignment of the domains within the magnet and can cause the pickup to work improperly. Never stack pickups next to each other for long periods of time. Stronger magnets can realign the magnetic domains in weaker ones which can alter the tone and output of a pickup.

409. I play upside down, can I reverse the pickups in my Strat or pole pieces?
The standard cavity routing in Stratocasters won’t allow for you to reverse the pickups in your instrument. You need to have a custom pickup builder make pickups with a reverse magnet pattern. The way you play is similar to what Jimi Hendrix did playing a right handed guitar left handed. He got the benefit of having a different pole pattern on his upper strings that helped contribute to his unique sound and experimental feedback. Trying to remove the polepieces in a bobbin made from vulcanized fibre will likely destroy your coil. I’ve reversed magnet Alnico rod polepieces in Fender pickups where the bobbin is molded out of nylon. The magnets are insulated by a thin wall of plastic that keeps the coil from being in direct contact with the magnet. Otherwise I wouldn’t attempt to remove magnets unless you need it rewound.

410. I removed the magnet from my humbucker and when I put it back the pickup was out of phase with my other, why?
It is a common thing that often happens when experimenting with pickups. Simply remove the magnet from the pickup you were experimenting with and slowly remove the bar magnet, once removed flip over 180?‘s and re-insert into the pickup. Make sure the screws and loose hardware are firmly secured to eliminate vibrations in components that could cause feedback when playing at higher volumes.

411. Should I remagnetize my magnets?
Remagnetizing magnets in guitar pickups can change the tone and output of a pickup. Trying to make a weaker magnet stronger depends on the chemical composition and grade of the material. There are several ways to magnetize by using Permanent-magnet magnetizers, Impulse magnetizers, Semi-continuous DC magnetizers, Half-cycle magnetizers etc. If a magnet has become demagnetized for some reason, you will most likely hear a brighter and louder sounding pickup after it is remagnetized. With magnets there is Magnetization, Demagnetization, Stabilization and Calibration. Older instrument magnets have be magnetized by using two large coils and a car battery for a DC power supply such as Leo Fender and Doc Kaufman used during the late 40’s. Doc told me they would magnetize the various magnets and realized as the battery got weaker, the magnets got weaker. Magnets need a certain amount of Ampere Turns (NI) to align the domains within the magnet to maximum efficiency.

412. What are the commonly used magnets?
The most common are the Alnico rod and bar types used in most instrument pickups. Some common grades are:
Alnico 2 10Al, 19 Ni, 13 Co, 3 Cu, Bal. Fe
Alnico 3 12 Al, 25 Ni, 3 Cu, Bal. Fe
Alnico 4 12 Al, 27 Ni, 5 Co, Bal. Fe
Alnico 5 8 Ni, 14 Ni, 24 Co, 3 Cu, Bal. Fe (most common)
Alnico 8 7 Al, 15 Ni, 35 Co, 4 Cu, 5 Ti, Bal. Fe
Ceramic 7 MO-6Fe2O3
Cunife 1 60 Cu, 20 Ni, 20 Fe
There are various dimensions and grades used for specific purposes and even variations or tolerances within each. Ceramic magnets are also commonly used in pickups and are much cheaper than sand cast or sintered Alnico magnets. Fender has used various sizes of rod magnets and different lengths to compensate for the different output of each string. Due to modern alloys and better consistency, the strings being manufactured today have a pretty good balance or output from string to string and pole to pole.

413. What are the different kinds of magnets?
The most common are:
Cobalt Steel: various grades- 3 1/2%, 3%, 17%, 36%.
Alnico: common grades- 1, 2, 3, 4, 5, 5DG, 6, 8, 8HC, 9.
Sintered Alnico: various grades- 2, 5, 6, 8, 8HC.
Ceramic: various grades- 1, 2, 3, 4, 5, 6, 7, 8.
Cunife: various grades- 1, 2.
Vicalloy: common grade- 1
Remalloy:
Rare Earth Cobalt:
Each type of magnet has various grades and compositions that change the strength and workability of that particular magnet.

414. What are the rough pits on rod and bar magnets?
The surface pits are a result of sand casting when the molten material is poured into a preparation shell form made from sand and binders. At times air pockets can occur and also piping is the small hole often seen at the ends of the magnet as it is formed. Magnet rods and bars are often molded oversize and rough shaped in a particular cast. The rod magnets are center-less ground to the desired OD (outside diameter) and cut to the desired lengths. During this process chipping can occur on the ends of the magnets during the chamfer (angle) process. Fine Aluminum Oxide or Diamond wheels are good for grinding Alnico magnets.

415. What are the various magnet shapes?
There are many standard and custom shapes that magnets can be made into. Some standards for Alnico’s are:
Blocks, U-shapes less than 180?‘s, U-shapes more than 180?‘s, C-shapes, Rods, Bars, Squares, Rectangular, Chain Cast or break off, Slugs, Rings, Bowl, Cups, Side Poles, Internal Radial Poles, E-shapes.
Some standards for Ferrites are:
Plates, Blocks, Slabs, Disks, Rings, Rectangular Bars and Arcs.

416. What are the various magnetic field patterns on popular pickups?
Four effect: A standard Gibson style humbucker where the adjustable polepieces extend out the bottom of the adjustable side of the pickup. You have a slight loss of magnetic field out the bottom of the pickup. The stud side has direct flow of the magnetic field to the strings and is the brighter side of the pickup.
One effect: This is the standard magnetic pattern for a single coil pickup with no ferrous bottom plate to direct the magnetic field. The majority of Fender style pickups have this effect where the magnetic field extends from the top and bottom. You lose efficiency from this pickup design but they have a unique tone and output.
H effect: This is the magnetic field pattern of a humbucker that has a double row of adjustable pole pieces such as the Gretsch Filtertron and other modern humbucking pickup designs. In this design, there is also a loss of magnetic field out the base of the pickup but these are great pickups designed by Ray Butts and have a unique sound and tone.
U effect: This is a magnetic field pattern where the polepieces are flush and in direct contact with the bar magnet within the pickup. There are no extensions from the bottom of the pickup where there might be magnetic field loss. These pickups tend to be brighter and gain slightly more output. Many “rail” type pickups have U-effect and are pretty loud for their size.

The magnetic field pattern is an important factor in determining the output and sound of various pickups. The idea came from looking at the side profile of the pickup and trying to see how the magnetic field traveled through the coils. I then came up with these terms as an aid to help explain the mysterious magnetic patterns that travel through a coil and when the magnetic field is disturbed. As the string movement occurs it produces a small amount of alternating current that tailored by the controls before going to the amplifier. I feel the more direct and concentrated the magnetic field is to the string helps produce brighter and tighter sounding pickup that retains the high-end and less loss of magnetic field that will give the pickup more power. This all depends too the type of coil, number of turns, proximity of the coil to the magnetic field etc.

417. What does a un-cut or ground bar magnet look like?
The raw material such as Alnico rod and bar magnets look very pitted and the surface is dull and dark brown. This is usually caused by the magnets being cleaned with steel shot, walnut shells or sandblasting. Often the sand casting causes many pits and a rough surface. Most magnets used in instruments have surface grinding done to correct tolerances and appearance.

418. What does a non cut or ground magnet rod look like?
Using for example an Alnico 5 rod magnet that’s uncut usually starts in lengths between 6.5 and 11.5 inches long. It has a rough surface and made by larger mills. After the rod stock is ready for shipping and sent to many smaller job shops that surface grind the rod magnet to the proper diameter and cut to the desired length. Early Fender magnets were cut to the desired length and many were not surface ground as the raw magnet stock was cast close to the desired diameter. The surface grinding is done to help get rid of pits, fissures and other chips and imperfections. The newer magnets are cast a little larger to help give a better surface appearance when surface ground. The majority of all Alnico rod magnets are sand cast or sintered.

419. What does re-magnetizing do to the sound of a pickup?
If a magnet becomes weak that’s used in a pickup, the sound will be less bright and less output. When you re-magnetize a magnet that has become weaker it re-aliens the magnetic domains within the particular magnet you are charging providing your magnetizer has enough ampere turns to fully charge the magnet. Also using a stronger magnet with a horseshoe shape can reverse the magnetic poles and also charge the weaker magnet. This has to be carefully done as it can change the magnetic field within the magnet you are charging as you remove the stronger outside force. As you pull the larger field away, it will want to pull the field in a weaker magnet. Using a magnetizer with a large DC coil works quite well, but you need to wait a few seconds till the magnetizer becomes stable. The most noticeable effect on the newly charged magnet will be more output and a brighter signal. You will also get more string pull if the magnetized poles are too close to the strings. This can reduce the sustain you have on your instrument, and can overload the input of effect pedals and cause more distortion in your system.

420. What effect does moving a magnet further away from the coil?
When you decrease the amount of magnetism or increase the magnetic gap between the magnetized poles and strings, you will decrease the output and tone of a pickup. The less magnetic field to the strings also decreases the amount of magnetic field movement or induced alternating current through the coil. The combination of string vibration and magnetic field passing through the coils in your pickup actually generates low amounts of electricity. The fewer flux lines the strings have to move through the coil will make the pickup sound softer and again less output or signal. You may get a cleaner tone when you pluck the strings by keeping the pickup further away. You also need to get the pickup closer for more output when using lighter gauge strings or you need to move the pickup further away when using heavy gauge strings. Using heavy gauge strings and having the pickup as close as possible will give you the maximum output, sustain and distortion. Using light gauge strings and having the pickup far away will give you the least output, sustain and less distortion.

421. What elements effect the strength of a magnet?
It’s the quality and percent of elements combined to make a particular grade of magnet material either in rod, bar or other custom shape. How and the type of magnetizer that is used is very important. Magnetizers can fully saturate or magnets can be calibrated to a desired strength. The type of magnetic path within a pickup is very important to how effective the magnetic field works between the strings and coil. When fully magnetized there is maximum alignment of the domains within each magnet. Magnets can become de-magnetized from several things such as heat when grinding, being hit with a metal object, AC current or transformers, time and environment. Another factor is size and shape of a particular magnet and it’s proximity to another.

422. What happens if the pickup is de-gaussed?
You will notice less output and at times a pickup can become out-of-phase with another. The pickup will lose it’s brightness and perhaps output from string to string. You would need a qualified repair shop to properly re-magnetize and calibrate your magnet within your pickup.

423. What happens if you grind a magnet?
I’ve seen many Telecaster pickups where the raised D & G poles have been ground down to simulate Fender pickups from the ‘50 to ‘54 era with flat poles. Grinding magnets with wound coils often becomes so hot it causes the insulation on the magnet wire to melt and eventually fail. If the magnet is magnetized it can become demagnetized depending the heat and duration. Also grinding a magnet can leave powdered chips and dust that can attach to other parts of the pickup. A magnet should be wet ground and unmagnetized. This will keep the slurry from attaching to the magnet and keeps the magnet material from discoloring from the extreme heat that can occur when grinding. Industrial grinding of magnets is very important as it keeps close tolerances for end users. Surface grinding is important for cosmetic appearance for end users. Round rod magnets are surface ground to the proper outside diameter. The .187” diameter rod magnet has become the standard for many guitar pickup manufacturers and is ground down from an average .194” magnet rod stock from the mills.

424. What happens if you re-magnetize a pickup?
Magnets can be magnetized or re-magnetized with the magnet in or out of a pickup. Some winders magnetize the magnets before winding the bobbins and some magnetize the magnets after the bobbins are wound and assembled. You get a different magnetic field pattern from a bar magnet if you magnetize it out of a pickup alone or install it and magnetize it when assembled in the pickup.

425. What happens if you remove the magnet from a pickup?
A magnet is in a pickup basically to magnetize the string. When the string vibrates, it moves the magnetic field within the coil and generates an alternating current. By removing the magnet in a pickup, there will be little residual or no magnetism needed to magnetize the ferrous string. There would be little or no output from the pickup.