Turntable Headshell Connector

One of the biggest challenges in this turntable build was attempting to recreate the headshell connector.  This part allows for quick and easy interchangeability of needle cartridges between turntables.  Otherwise, I would have to unscrew and disconnect the cartridge cables every time I wanted to remove it.  Wanting this turntable to be compatible with my other ones, which accept standard headshells, I figured I had no choice but to make this connector.

The challenge here was the amount of small and complex parts needing to be made; a threaded locking mechanism, a slotted body, and insulated piece to house four spring-loaded brass contact pins, and the pins themselves.  Then on top of this, figuring out how it will connect to the tonearm and wiring it.

My version did a fair job replicating it, but it took a lot of hard work, several failed attempts and a few design flaws.  Part of the reason for my shortcomings was the fact that I didn't want to disassemble my Technics to see how it worked.  I just did the best I could from the measurements I could get on the outside.

Here's a diagram of my headshell connector.  The biggest difference between mine and the Technics is a snap ring holding on the locknut.  This is because my tonearm is a larger, and having to match this larger diameter on the connector, I couldn't slide the locknut on through the back.  On the Technics, the locknut is secured by a shoulder on front of the connector body.

Turntable Tonearm Linkage

Now that the turntable base and platter have been completed, the next step was to machine the tonearm components.  This assembly consisted of several parts which, though I tried to simplify it, ended up being one of the most complex and time consuming parts of the project.

I decided early on that I wasn't going to attempt recreating this gimbal mechanism the Technics has.  My version also omits several features for simplicity.  Namely, the anti-skating function and tonearm lift.  I was originally going to make the clip for securing the tone arm, but never got around to it.  I did however include a height adjustment for leveling the tonearm with the platter, but a more crude version.  I also made mine with a straight tonearm instead of the S-shaped.

My version:

Here's a diagram of the tonearm linkage and how it connects into the turntable.  Note, I ended up not using the locknut in the final build (above photo) because the tonearm would've been too high.

Casting The Turntable Platter - Sweep Pattern Experiment

The next step for the turntable project was to make the platter.  This was the second of the two cast aluminum components to make, and unlike the Technics which is die cast, this too would be sand casted.  However, this time I chose a different molding method called "sweep casting" which is applicable to radially symmetric parts like this.  This was my first time trying this, and I had relatively favorable results.

The sweep pattern is basically a cross section of the part being casted, which is swept around a central axis to remove pre-rammed sand layer by layer.  Think of it like those center pivot irrigation systems, except instead of watering crops, we're removing sand to create a mold cavity.

This has the advantage of saving time since I didn't have to make an entire wooden replica of the turntable platter.  I began by transposing the final dimensions of the platter, plus shrinkage allowance, into a flat piece of plate.  Pardon the atrocious blueprints

Machining The Turntable Base Casting

Now that the turntable base has been cast, it's time to machine the features to make it functional.  I started by setting it up on the milling machine upside down with spacer blocks underneath, and clamping through the middle.  In this setup I faced the bottom contour.

Here is a closeup of the finish, now the base will sit flat for the next setups.

Jigsaw Blade Clamp Repair (U-Shank to T-Shank Conversion)

Jigsaw blades are available in two major styles: U-shank and T-shank.  Unfortunately, I was unaware of this fact when I bought my first jigsaw at a garage sale for $5.  I mistakenly bought a package of T-shank blades for it when it really took U-shank.

Not wanting to admit that I wasted $12 on the wrong blades for a $5 jigsaw, I decided to use them anyways because the package said, "Fits all jigsaws".  The blades did not fit properly and would slip out during use.  I still insisted they were supposed to work, so I tightened the blade clamp harder... too hard it seemed, since I'd cracked it right down the middle.

Small Mill, Big Vise

When I won my $500 All Industrial Supply shopping spree at the Bar-Z Summer Bash in 2018, my first inclination was to buy a Kurt vise for my machine.  However, after looking at the dimensions, it seemed that even the smallest vise was still too big for my tiny machine table.  The bolt locations would not have lined up with the T-slots, and I would've had to make a fixture plate to mount it.  Even then, there might've been an issue with the vise handle interfering with my machine's Y-axis handwheel.  Not wanting to risk all this confusion, I remembered that my friend had won several vises at an auction which he wasn't using.  He was kind enough to let me have the one of my choice.

I ended up spending the $500 on other things.

The vise I chose was this large two-piece one, shown here next to a standard mill vise for comparison.  The thing I liked about this one, aside from virtually unlimited holding capacity, was the height of the jaws. By itself, the back jaw practically doubles as an angle plate!

Casting Coach Z's Medallion (Video)

I decided this year I wanted be Coach Z for Halloween, which finally gave me a use for all the scrap brass I'd been saving up!

Grain Mill Part 6 - Failed Roller Idea

When constructing the rollers for the grain mill, my original intent was to clad them with this stainless steel tubing because it felt more sanitary than having regular steel contacting the grain.  This didn't entirely work out for a few reasons.
Here we begin right after I had just finish turned the rollers to size.  The size was chosen for a press fit of this 2.5" diameter stainless tubing.  I began by hammering it onto the roller.

Grain Mill Part 5 - Nut Cracking Wheel

My vision for a grain mill that also cracks nuts didn't exactly work out the first time.  The major flaw was that putting a round nut between a driven and idle roller caused the second roller to spin backwards.  What I needed was a roller with lobes on it that would grip the nuts and force them into the other wheel instead of just slipping.

I had two options for making this;  1.  I could start with round material and mill a bunch of slots in the sides, or 2.  I could start with a rectangular piece, drill a bunch of holes in it, then cut it out with the band saw and turn it on the lathe.  I chose the second option because it sounded like more fun.

Grain Mill Part 4 - Hopper

The next order of business for the grain mill was to construct a hopper to hold the pre-milled grain.  I decided on a one-piece folded design made from a scrap stainless steel trash can.

Here I am cutting out the flat pattern with aviation snips, and also punching holes in some of the corners.

Grain Mill Part 3 - Assembly

Now that the rollers and housing have been completed, a few more articles need to be attended to before assembly can begin.  Firstly, we'll look at the handle.
I found this big cast iron handle at a garage sale for $2 which seemed like the perfect candidate for this build.  However, it needed a hole tapped in the side for a set screw to secure it to the fixed roller's shaft.

Grain Mill Part 2 - Rollers

My selection of roller size was decided by the fact I had two identical scrap pieces of 3" diameter steel sitting around.  I thought it would finally be a good use for them.  What I failed to consider was that a larger roller would result in more force required to mill grain.  This is due to two factors:  The shorter lever arm between the end of the handle and milling surface, and the larger contact area from the increased radius of curvature.  This I wouldn't realize until the testing phase.
Design wise, one roller is fixed, and the other is movable to allow variable spacing for different sizes of grain, nuts, and so forth.  The fixed roller would require a longer shaft for attaching the driving handle.  For this reason, I decided to make the fixed roller in two pieces, while the movable roller has the shaft built in.  The fixed roller is secured to the bearings with set screw collars, while the movable roller is held by two 3/8"-16 bolts through either end.  This was another design flaw that I wouldn't realize until later when I found out the bearings for the movable roller weren't actual ball bearings and would seize up when tightened down.

We begin with the movable roller.  First turning one end, and roughing the diameter for the bearing.

Grain Mill Part 1 - Housing

We begin the grain mill build with the outer housing.  I decided to make this from some scrap pieces of 1/2" thick stainless steel.  Firstly, squaring up all the sides in the milling machine.

Next, I drilled screw and dowel holes in the side pieces.  The screw holes were drilled 9/32" to clear 1/4"-20 screws, and the dowels were reamed for 1/4" dowels.  The dowels ensure more precise alignment of the housing pieces.

YouTube Recap | Videos from December 2019

In case you are not subscribed to our YouTube Channel or you missed one, here are the videos we released in the month of December 2019! In total, a total of 5 vids were released, making for a total of 73 on the year. What a year this has been! Our channel has grown substantially. At the time of my typing, we've hit 312 subscribers. We'd like to thank you for joining us on our journey and stay tuned for next year. More videos are coming in the next year, so don't forget to subscribe!

Make your own Chicken Biscuits
"After making those delicious biscuits, I had to put some chicken in between them. Here's the recipe if you want to make some also!" -- Vinny

YouTube Recap | Videos from November 2019

In case you are not subscribed to our YouTube Channel or you missed one, here are the videos we released in the month of November! In total, a total of 5 vids were released. This month had some excellent cooking, homebrewing, and machining videos! More videos are coming, so don't forget to subscribe!

BEST Maple Mead | Learn to make Mead
"That mead recipe from a few years ago was so good, I decided to make a video out of it!" -- Vinny

YouTube Recap | Videos from October 2019

In case you are not subscribed to our YouTube Channel or you missed one, here are the videos we released in the month of October! In total, a total of 6 vids were released. This month had some excellent cooking and machining videos! More videos are coming, so don't forget to subscribe!

Harvesting Grapes Grown in 5 Gallon Buckets | Container Vineyard Harvest 2019
"Another good year in the vineyard." -- Vinny

YouTube Recap | Videos from September 2019

In case you are not subscribed to our YouTube Channel or you missed one, here are the videos we released in the month of September! In total, a total of 6 vids were released. This month had some excellent cooking, gardening, and behind the scenes videos! More videos are coming, so don't forget to subscribe!

Gardener Reacts to the Farming Skill in RuneScape
"After all the RuneScape references we've made over the years, I decided it was time to make a RuneScape video." -- Vinny

YouTube Recap | Videos from August 2019

In case you are not subscribed to our YouTube Channel or you missed one, here are the videos we released in the month of August! In total, a total of 6 vids were released. This month had some excellent cooking and gardening videos! More videos are coming, so don't forget to subscribe!

Best French Bread Dinner Rolls Recipe | Learn how to Bake
"I finally found a recipe for bread that I liked. A lot." -- Vinny

YouTube Recap | Videos from July 2019

In case you are not subscribed to our YouTube Channel or you missed one, here are the videos we released in the month of July! In total, a total of 7 vids were released. This month had some excellent metalworking and gardening videos! More videos are coming, so don't forget to subscribe!

I Made Wine from Golden Beets. Here's how it Tastes
"Did I end up liking this wine after making it?" -- Vinny

The Foundry - First Attempted Production Run with The Molding Press - Casting Soap Dishes with The Foundry (Video)

In this video, I fire up the foundry to attempt to cast a lot of aluminum soap dishes. I put the soap dish mold and molding press to the test to see how they stand up to a full production run. Leave a comment in the video if you are interested in buying an soap dish.

Back to episode 14: Building a Permanent Molding Press

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