slowburnaz
Commercial User
Agreed... very cool! I imagine it would be something like one half of a sidewinder for each.
I like it!
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Magnets & Copper Wire: A Pickup Building Thread
- Thread starter Freekmagnet
- Start date
Agreed... very cool! I imagine it would be something like one half of a sidewinder for each.
I like it!
I do have to give credit to the discussion we had in here maybe 6 months ago, when I was building a Jazz pickup with a steel blade and narrow ceramic bars on the bottom. Someone (Bruce I think?) made a comment about putting it in the bass upside down, i.e. magnets towards the top instead of on the bottom. I tried that, and just for kicks I tried laying the pickup on it's side too. That's what got me thinking about doing a sidewinder that was structured something like this. And, also trying to push space efficiency in terms of packing wire close to the magnets, especially when using thicker wire. A taller coil works better for that but at some point a coil is too tall to be practical, so why not turn it on it's side? Then you can grow it in "width" out to the shape of a soapbar instead of having a really tall pickup.
What if it was MM pickup size? Is it possible for a coil to be too tall, in terms of functionality?
The pickups I'm making for my basses right now use 3/8" dia x 1" A5 magnets and tall slim coils around them. They function beautifully; powerful, wide range, exceptional clarity and detail. But the completed pickup ends up being about 1 1/4" tall overall. It took some engineering to fit it into the body, because of the depth. That's about at the practical limits for tall coils. But I don't think that's the limit of the magnetic/electric function. I could go taller.
When I increased the size of my coils and magnets from 3/4" tall to 1" tall, the output level increased about 25%-35%. About what I'd expect for the increase in power of the magnets. So I guess that means that the coil is "feeling" that power. The coil wasn't losing efficiency by being taller, as long as it was still within the field.
Funny you should mention that, I have an MM sized version of this drawn up too. At first I was going to try to fit four coils in it, as in two rows of this design, but then I decided to draw it as one set of coils that were super "tall" just to see what it would be like. I don't think there is a limit or even a point of diminishing returns in terms of taking this to extremes, it's really just a matter of how much copper can you fit in a given pickup footprint. Or how big of a custom size/shape pickup you can fit in a given body.
Part of me worries that all of this steel is going to impact the top end a little too much but I guess if it sounds terrible I can retry with 1/16" steel slugs.
slowburnaz
Commercial User
Though I don't span the whole MM width in mine, I do a sidewinder in MM size:
I don't see why it wouldn't work with Dwizum's format, though, either. It would effectively be a really wide aperture, so I bet it would reproduce a pretty strong fundamental signal.
In a side winder like that, are the magnets all N facing the center from both sides, or are they both facing the same direction so you have a N and a S facing the center?
slowburnaz
Commercial User
They're all situated so the same polarity faces inward.
Part of my regular business here is machining up special tools and fixtures for other Luthiers...and that includes pickup makers. I'd like to show you folks, who build pickups, a custom drill fixture that I just finished up for Rob Timmons of Arcane Pickups. I've building stuff for Rob for many years, helping him making the metal parts for his pickups. Sometimes he has me make the parts; other times I make the tools for him to make the parts.
Back in 2011, I built him a simple drill fixture that's built into a small machinist's vise. It's made for accurately drilling (8) 1/8" holes in a small strip of steel; a keeper bar for one of his pickups. He loved it and used it for a decade making the parts. He finally wore it out. The guide holes became sloppy. So, he asked me to build a new one, but with a thicker drill guide bar.
Here it is:
It's made from a standard small drill press vise (also called Machinist's Vise). This one is a 3" wide Palmgren, which is good quality US-made. Rob bought it used somewhere. The cheap import versions of these vises work fine too. These vises all have steel smooth jaws that unbolt with screws. You can see the original jaws in the background on the left.
The fixture kit is a new pair of aluminum jaws, machined from bar stock, which bolt into the vise in place of the original jaws.
The guide block is just a piece of 1/2" x 3/4" mild steel bar stock. In the milling machine, I accurately drilled the row of holes, then pressed the two 1/8" x 1 1/4" dowel pins in the two end holes.
In the middle is a sample part that I drilled with the fixture. It's a keeper bar for one of Rob's pickups. It's made from 1/8" x 3/16" 1018 steel bar stock, with (8) 1/8" holes drilled in it.
Note: This drill guide fixture has a (10) hole pattern. Most of his keeper bars get (8) holes, but one version gets (10) holes. So, he had me make the fixture to handle both.
Here's the basic idea behind the fixture: The part fits down into a milled slot in the top of the aluminum jaws. The slot is split, half on each jaw. Tightening the vise clamps the part between the jaws.
The two pins at the ends of the steel drill guide block go into a pair of holes at the ends of the jaws. These holes are drilled right down the center of the split between the jaws. So, tightening the vise also clamps the two pins, holding the drill guide block accurately and tightly in position over the part.
Here's what the outer aluminum jaw looks like. Half-holes for the guide pins, and clearance holes under the part for drilling through.
On the inner jaw, I milled away an inner chamber under the drilled holes. This is for the steel chips to fall down through the fixture and through the bottom of the vise.
To use the fixture, I start with a strip of the steel bar stock, cut off to the right length. It should fit nicely between the two pins of the guide block. The block serves as a checking gauge.
With the vise opened slightly, I place the steel part into the groove in the top of the aluminum jaws, and set the guide bar down over it. The pins of the guide bar go down into their holes in the jaws, and hold the part in position between them.
I tighten the vise, which clamps the guide block in place and holds the part in accurate position. I set the vise in the drill press and drill all the holes down through the guide block. I use a 1/8" Screw Machine Drill bit.
Unclamp the vise, lift up the guide block, and take out the part. After a quick light countersinking/deburring, it's done. Positional accuracy of the holes is about +/- 0.002".
I'm showing you this to give you ideas for making up similar fixtures, for making your own metal parts. I've built maybe a dozen of this style of fixtures, for my own use and for other Luthiers. I buy these little machinist's vises on CraigsList or ebay or Harbor Freight.
The aluminum jaws and guide block are easy to make up if you have a small milling machine. And every household should have one, of course! But you can make these parts up with a drill press and a hacksaw.
Back in 2011, I built him a simple drill fixture that's built into a small machinist's vise. It's made for accurately drilling (8) 1/8" holes in a small strip of steel; a keeper bar for one of his pickups. He loved it and used it for a decade making the parts. He finally wore it out. The guide holes became sloppy. So, he asked me to build a new one, but with a thicker drill guide bar.
Here it is:
It's made from a standard small drill press vise (also called Machinist's Vise). This one is a 3" wide Palmgren, which is good quality US-made. Rob bought it used somewhere. The cheap import versions of these vises work fine too. These vises all have steel smooth jaws that unbolt with screws. You can see the original jaws in the background on the left.
The fixture kit is a new pair of aluminum jaws, machined from bar stock, which bolt into the vise in place of the original jaws.
The guide block is just a piece of 1/2" x 3/4" mild steel bar stock. In the milling machine, I accurately drilled the row of holes, then pressed the two 1/8" x 1 1/4" dowel pins in the two end holes.
In the middle is a sample part that I drilled with the fixture. It's a keeper bar for one of Rob's pickups. It's made from 1/8" x 3/16" 1018 steel bar stock, with (8) 1/8" holes drilled in it.
Note: This drill guide fixture has a (10) hole pattern. Most of his keeper bars get (8) holes, but one version gets (10) holes. So, he had me make the fixture to handle both.
Here's the basic idea behind the fixture: The part fits down into a milled slot in the top of the aluminum jaws. The slot is split, half on each jaw. Tightening the vise clamps the part between the jaws.
The two pins at the ends of the steel drill guide block go into a pair of holes at the ends of the jaws. These holes are drilled right down the center of the split between the jaws. So, tightening the vise also clamps the two pins, holding the drill guide block accurately and tightly in position over the part.
Here's what the outer aluminum jaw looks like. Half-holes for the guide pins, and clearance holes under the part for drilling through.
On the inner jaw, I milled away an inner chamber under the drilled holes. This is for the steel chips to fall down through the fixture and through the bottom of the vise.
To use the fixture, I start with a strip of the steel bar stock, cut off to the right length. It should fit nicely between the two pins of the guide block. The block serves as a checking gauge.
With the vise opened slightly, I place the steel part into the groove in the top of the aluminum jaws, and set the guide bar down over it. The pins of the guide bar go down into their holes in the jaws, and hold the part in position between them.
I tighten the vise, which clamps the guide block in place and holds the part in accurate position. I set the vise in the drill press and drill all the holes down through the guide block. I use a 1/8" Screw Machine Drill bit.
Unclamp the vise, lift up the guide block, and take out the part. After a quick light countersinking/deburring, it's done. Positional accuracy of the holes is about +/- 0.002".
I'm showing you this to give you ideas for making up similar fixtures, for making your own metal parts. I've built maybe a dozen of this style of fixtures, for my own use and for other Luthiers. I buy these little machinist's vises on CraigsList or ebay or Harbor Freight.
The aluminum jaws and guide block are easy to make up if you have a small milling machine. And every household should have one, of course! But you can make these parts up with a drill press and a hacksaw.
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I got to try that new pickup out this morning before work for a couple minutes.
They are very promising. Tons of low end. More powerful and more clear than I had expected. If anything, a little TOO powerful, and a little too scooped almost to the point of being a little brittle on the top and a little muddy on the bottom. I think I wound them with more turns than they need given the magnet structure, so the next version will be maybe a thousand turns less. I'm going to try that on these same bobbins before I make any more flatwork, so I can be sure I have the whole design finalized before moving on. They're very modern sounding, almost like an EMG DC. It probably doesn't help that I put stainless strings on this bass in an attempt to get a little more zing from the prior set of pickups. I may try these with nickel strings before making a lower-wind version, but there's definitely wiggle room for fewer winds being helpful anyways so I will still try that.
I feel that this design is accomplishing what I was hoping for. The tonal character of a pickup with a wide magnetic field, with the "efficiency" of a pickup that's a tall/narrow coil with the wire all packed close to the magnets.
I made these with 1" wide 1/8" bar stock because the vendor I used only has rounded-corner bar stock in 1" or 1.5" and the 1.5" seemed like it would be too wide (the two bars would be nearly touching in the middle in order to avoid being too wide for the format). I wish I could find 1.25" wide 1/8" bar with the rounded corners. Maybe I need to just keep looking. The magnetic field is definitely wide enough as is, but if I bend either of the two middle strings REALLY far towards the center, you can hear the output start to fall off. I don't think this is a serious problem because I can't imagine a bass player would ever bend a string that far.
They are very promising. Tons of low end. More powerful and more clear than I had expected. If anything, a little TOO powerful, and a little too scooped almost to the point of being a little brittle on the top and a little muddy on the bottom. I think I wound them with more turns than they need given the magnet structure, so the next version will be maybe a thousand turns less. I'm going to try that on these same bobbins before I make any more flatwork, so I can be sure I have the whole design finalized before moving on. They're very modern sounding, almost like an EMG DC. It probably doesn't help that I put stainless strings on this bass in an attempt to get a little more zing from the prior set of pickups. I may try these with nickel strings before making a lower-wind version, but there's definitely wiggle room for fewer winds being helpful anyways so I will still try that.
I feel that this design is accomplishing what I was hoping for. The tonal character of a pickup with a wide magnetic field, with the "efficiency" of a pickup that's a tall/narrow coil with the wire all packed close to the magnets.
I made these with 1" wide 1/8" bar stock because the vendor I used only has rounded-corner bar stock in 1" or 1.5" and the 1.5" seemed like it would be too wide (the two bars would be nearly touching in the middle in order to avoid being too wide for the format). I wish I could find 1.25" wide 1/8" bar with the rounded corners. Maybe I need to just keep looking. The magnetic field is definitely wide enough as is, but if I bend either of the two middle strings REALLY far towards the center, you can hear the output start to fall off. I don't think this is a serious problem because I can't imagine a bass player would ever bend a string that far.
I'm a level 3 wood monkey. This pickup building is level 7 wizard stuff.
slowburnaz
Commercial User
Having a +3 Winder of Scattering and an Enchanted Spool of Endless Copper certainly helps.
Those are really cool and have a unique look.
Wait 'till you see the final version with the "pretty" materials!
Nice job! Those look amazing and I bet they sound awesome!
I thought you were on vacation…
Unfortunately not - just spending several long weekends in a row at my deceased father in law's house filling dumpsters so we can sell the place. He was a pipefitter, welder, and general handy guy so I have scavenged several really nice tools. But pickup making time is down from several hours a week to about half an hour on Tuesdays and Wednesdays for the forseeable future...
Ugh. I can sympathize with how much hard work that is. In the past several years, I've had to clean out the shops and tool collections of two friends who have died. I'm a hopeless collector of tools and machines, and to have to go through and dispose of someone else's collection was sobering and painful. And a lot of hard, heavy work.
Since I have sketchy health, I've put all my affairs in order, but I have not truly made my workshop and music stuff estate-friendly. I've been thinking of going around putting values on small bits of tape right on each item to make it easier to value when I'm gone. I did a master list of things a couple of years ago, but it won't help them if they can't cross reference the list to the actual item. 
He had a giant garage with two lean-to outbuildings and a shed that were literally crammed wall to wall - you couldn't even walk through the garage. He had sorted out some of the bigger things and already passed them on to others, but it's pretty incredible to work through what's left. I think he owned 4 or 5 of most tools. There must have been a thousand random hand tools, if you counted every socket, wrench, screwdriver, etc.
