Stern Tech School: Adjusting Factory Settings on King Kong Assembly

Stern Pinball·video·14m 41s·analyzed·Jun 23, 2025

Analysis

claude-haiku-4-5-20251001 · $0.019

TL;DR

Stern Tech School guide for King Kong animatronic removal, servo clocking, and recalibration procedures.

Summary

Kyle from Stern Pinball Tech School provides a comprehensive technical guide for removing, servicing, and recalibrating the King Kong animatronic assembly used in King Kong and Avatar pinball machines. The tutorial covers mechanical disassembly, servo motor clocking procedures, calibration mark alignment, and the critical distinction between factory calibration values stored on the node board versus software calibration stored on the SD card. The video emphasizes that factory reset behavior depends on whether the assembly's physical position has been modified, requiring operator understanding of the dual-storage calibration system.

Key Claims

King Kong assembly calibration values are stored on the node board at the factory, not on the SD card
high confidence · Kyle explicitly explains that factory calibration values are stored on the node board and will be retrieved during factory reset if the assembly position hasn't been altered
The servo motors in the King Kong assembly have 25-tooth splines and must be re-clocked to vertical position after arm removal to maintain full range of motion
high confidence · Kyle demonstrates the motor clocking procedure and explains that non-360-degree rotation motors need to be positioned vertically at stop to enable full software calibration range
If the Kong assembly is removed and reinstalled without changing arm position, calibration values do not need adjustment
high confidence · Kyle explains Scenario 1: factory calibration values will work correctly if physical assembly position unchanged
If Kong arms are removed and repositioned, new calibration must be written to the node board to preserve settings after factory reset
high confidence · Kyle describes Scenario 2 and the factory default adjustment procedure that writes current calibration to node board
King Kong uses three servo motors: left/right body motion servo and left/right arm servos controlled by a servo control board
high confidence · Kyle identifies and demonstrates the three servo motors inside the Kong assembly after removing the back plate

Notable Quotes

“Unless you put this arm on in the absolutely exact same position you removed it from it is going to be out of calibration.”
Kyle@ 3:31 — Critical warning about servo spline positioning; establishes the technical complexity of Kong service
“The reason being is since the motors do not have a 360 degree rotation, we'll put them into an up position so the calibration and software will be able to move through its full range.”
Kyle@ 4:46 — Explains the engineering principle behind the motor clocking procedure and why vertical positioning is essential
“The calibration values are done in the factory and those values are stored on the node board not on the SD card which is stored on the computer.”
Kyle@ 8:12 — Key distinction between dual storage locations that affects troubleshooting and factory reset behavior
“If you were to ever factory reset your game and you have never messed with the position of King Kong at all it would pull those factory values from the node board and use those for all of King Kong's movements.”
Kyle@ 8:28 — Explains factory reset behavior when assembly position is unchanged
“In the future, if you were to ever factory reset your game, it is going to store those values to what you currently have it assembled as, not what it was assembled like at the factory.”
Kyle@ 9:31 — Demonstrates the purpose of the factory default adjustment procedure and its persistent effect on calibration storage

Entities

KylepersonStern PinballcompanyKing KonggameJames Cameron's AvatargameStern Tech Schoolorganization

Signals

?
community_signal: Stern Pinball producing detailed technical education content for operator and owner support, demonstrating commitment to machine maintenance and troubleshooting accessibility
high · Comprehensive Tech School video series covering specific assembly service procedures with clear explanations of complex calibration systems
?
product_concern: Technical documentation and calibration procedures for King Kong suggest a complex animatronic system requiring operator-level service; the dual-storage calibration system (node board vs SD card) and factory default adjustment procedure indicate potential for calibration drift or loss
medium · Kyle emphasizes the importance of factory default adjustment procedures and explains scenarios where calibration values must be rewritten to persist after factory reset, suggesting real-world calibration issues occur

Transcript

youtube_groq_whisper · $0.044

0:00

Hi, I'm Kyle with Stern Pinball and in this video we are going to go over adjusting the factory default settings on your animatronic King Kong assembly. To remove the assembly from your play field we're going to need to have the glass off of the game so if you don't know how to do that we do have a video on our tech school playlist go ahead and refer to that. The tools will need to remove the assembly from the back panel are a quarter inch and a 5 16 inch nut driver. Once we have the glass off the game, pull the playfield up forward and rest it in the forward service position on the rubber feet in the front of the cabinet. With the playfield now in the forward service position we can go ahead and power the game off to remove the assembly from the back panel. For demonstration purposes I have the playfield propped up on the cabinet, but everything we need to address to remove the assembly is on the back panel. So we have our 48 volt power to the node board here, we've got our two data lines for the data bus here, and then we will need to remove the two quarter inch head screws here and the two 5 16 inch nuts that hold the assembly into the back panel here. These connections on the board do not need to be moved so do not touch those guys there just the two data and 48 volt power connections. With those removed and out of the way I'm going to start by removing the two screws on the bottom using my quarter inch nut driver here. Remove the quarter inch head screws down at the bottom. With those out of the way we'll get the 5 16 inch nut driver and remove the two nuts from the studs on the top side. I'm going to loosen them until they're just about at the end of the stud and then remove them with my fingers just to not drop washers or the nut or anything like that. With those removed, we can guide the assembly forwards off the back panel and then up and out of the game. Now that we have the assembly out of the game, let's take it over to the bench and take a closer look at the inside of the assembly. To get inside the assembly we need a number one Phillips screwdriver. On the back of the molded assembly we have a cover plate so we can remove these two screws and this will reveal the three servo motors that work the assembly. With the back plate off we can now see the three servos. So we've got the left and right servo motor, the right arm servo motor, and the left arm servo motor. Each of these servo motors plugs into this servo motor control board. This tells the servo motors what they're supposed to do. Let's remove one of the arms and we can see what we have underneath here. The arms are held in with, again, a small Phillips head screw. We'll hold the arm in place while we loosen it so we don't turn the servo motor. We get that loose and pull the arm off of the servo motor. You'll see that the servos have a 25 tooth spline. What that means is this arm has a matching spline with 25 indentations Unless you put this arm on in the absolutely exact same position you removed it from it is going to be out of calibration While we're looking at the arm, we can also see some calibration marks. These are marks that you will use when recalibrating the assembly as a visual guide when you're setting the calibration in software. How would you use these calibration marks? So in software, when you're setting the maximum up and maximum down levels, you'll want to adjust it so those calibration marks here are just visible and lined up with the flat portion of Kong's back. So that would be up, and we would move it down, down, down, down, and when it's lined up like that, that is our down position. Now we're going to remove the other arm so we can show the motor clocking procedure before we reassemble the sculpt.

4:34

When we reinstall the arms, we need to clock the motors so they will be in a known position. The reason being is since the motors do not have a 360 degree rotation, we'll put them into an up position so the calibration and software will be able to move through its full range. So we can use the arm like a wrench, we can put the splines onto the motor, and then gently crank the arm up. And that actually came out perfect. We want the arm to be vertical when the motor stops. And if we have a good vertical position on the arm when the motor is stopped, in software, we're going to be able to get a full range of motion. That's the downward stop position there. And there's our up stop position there. And those are the hard stops in the motor. Once we have the motor and the arm clocked correctly, we're going to tighten it back down to the servo motor. We'll do the same thing for the other side. And I'm going to rotate it upwards until it stops in a vertical position, just like the other arm. Before we tighten it down, let's just make sure we get the bottom stop, just like that. Retighten the arm here. Now we're going to reinstall the back plate or King Kong's backpack. Notice on one edge we do have a cutout. This cutout is for the servo motor's wiring loom here. So we want to make sure that we put the wiring loom through that cutout. Get Kong kind of squared up with the plate here, the backing plate. We can slide the plate back in, position the wiring loom like this in the plate, and then we can try to get these little cleats into the slit in the base of King Kong here so it sits just like that. So now the little cleats are installed in the plate here, and now we can take our screws and attach the plate here to the back of the assembly. Now that we have the assembly back together, we can take it back over to the game and reattach it to the back panel. Installation is the opposite of removal. We are going to take the King Kong assembly here and we are going to guide it into the back panel using the studs at the top of the assembly. And once we get it in, we can use the washers and nuts to tack it in place. So I starting from the top I using the nuts to hold the King Kong assembly from being able to fall off and out of the back panel Once I have the washers and nuts installed and hand tightened, I'm gonna drive them home and get them snug but not totally tight. Once those are in, I'm gonna take our other screws and I'm gonna install those through the bottom. Once those are tight, I'll move back up to the nuts and I will tighten those down. Alright, and with that we can reattach our 48 volt power to the node board and then get our node bus data cables and reattach those to the ports that they plug into and we have an installed Kong animatronic let's talk about the where the calibration values for King Kong are stored and why it is important if you were to remove King Kong from the game and then reinstall it but not change the position of the arms we would not need to adjust the calibration values. The calibration values are done in the factory and those values are stored on the node board not on the SD card which is stored on the computer. If you were to ever factory reset your game and you have never messed with the position of King Kong at all it would pull those factory values from the node board and use those for all of King Kong's movements. Scenario 2, let's say we did need to remove one of King Kong's arms and we put it back together. Now we would need to software calibrate it. When we calibrate King Kong, those values are going to be stored on the SD card. An adjusted calibration, not the one from the factory, right? In the future, if you were to ever factory reset your game, suddenly those software calibration values you had set up here are gone. and is going to pool the values that were done in the factory for the position it was set in there, not the position you currently have it assembled in. We'll have to go through a factory default adjustment procedure to now write the current and true calibration for the position you have King Kong in to the node board. So in the future, if you were to factory reset your game, it is going to store those values to what you currently have it assembled as, not what it was assembled like at the factory. Now with the game powered up, we are going to navigate to the calibration menu for the Kong mech. So go in here, down to device tests, and then to the Kong mech calibration. We'll familiarize ourselves with this screen really quick, but each of these selections here will be able to set a value for up or down. You'll see on the right hand side it gives us kind of a quick visual representation of what the correct position should look like when we're calibrating and then we'll see you know current or default values. We are going to be resetting these default values so we can set them to be totally factory fresh. Make sure you have your QR code ready, the one that was sent to you by support because on this screen when we scan that QR code it will erase the calibration. The other thing we're going to need is our number one screwdriver because we will need to pop the back plate off of Kong just a little bit so we can see the calibration marks that are put into the arms. So before we scan the QR code I am going to loosen the plate here and get this out of the way a teeny bit Now that we prepared to set the calibration I going to take the QR code and scan it Now that the QR code has been scanned we can see that the game now has no limits set At this point once we have all of these things said not set we are going to set each of these limits in the order from top down. So we're going to start with Kong's right arm. We need to make sure again that the calibration mark is lined up with the flat portion of Kong's body. So this one needs to come down considerably. With Kong's right arm lower limit selected, I'm going to now use the right flipper button and we're going to lower the value shown here and try to match the picture. So we're going to try to get the forearm to be about parallel with the playfield. Get it down into position. And now I'm going to check and see if I can see the witness mark, the casting mark in its arm. We're about lined up. I can move it a couple more steps to get it really perfect. And that is where we should be. Now with the value set, we are going to save it by pressing the black button. And we are going to move down to the next position, the right arm. I'm going to hit the black button here and we are going to start adjusting this value. I'm going to take a look for the mark here. It needs to rotate down a bit. Got that lined up pretty well. So we'll use the black button here to set our new value. We'll move to the left arm now. Looks like that needs to come down, so I'm going to adjust it downwards. Looks like that's just about right, so we're going to save this value here. So that is the lower position for the left arm. Now we'll check the upper limit. Pretty close, but we're going to move it down a little, go down to the clockwise limit. So for this we're going to want to make sure that we have the back panel pinched in and not leaning backwards. So what we're looking for is that back panel to be close but not touching the plastic back panel of the game. So I'm going to get in here and rotate it about as far clockwise as I can. It's touching a little bit. Let's move it forward a teeny bit. And that value looks pretty good to me. We'll set that value. And now we can set the counterclockwise limit. And this one's really simple. We're just trying to get the Kong assembly to be parallel with the back panel itself. So I'm going to rotate that one back to about here. And that looks about parallel. There is a bit of slop in the mechanism, so when you touch it, you might get a little bit of wiggle. But as long as it's looking parallel at this position, this is the right value. We'll sit this guy here. Now we are done. we can push the green button to move back, and we can write this calibration data to the node board.