Cool, favorited the thread and look forward to updates.

Wow great job! I’m excited for this.

Out of curiosity, does anyone know how the original chest mech worked? If it could somehow inherit it's motion from the chest fork, rather than run on its own motor, I think it would be cool.

The chest fork mech motion has a bit of "attitude" to it, in how it goes up slightly before it slams down.

You know, for the longest time chest shot rejects were caused by the fork mech getting loose. It would be a shame if the opening chest was junked without being the actual cause.

Well think of it this way, we have one solution that definitely works. Maybe there's another that also works without needing a servo, switch etc! I would be really interested to see the original mech...

Ah hah. Exactly as I suspected, the fork does the job of lifting the lid via a linkage.

How is the chest lid currently forced open? Was the hinge simply replaced with some sort of flange? In your pics, how does the linkage connect to the chest lid itself?

I'm not understanding what is going on in that video. Is there a separate coil for the chest lid? Or is it just connecting the hinge to the fork via linkage + seesaw?

Ah ok sweet. That is what I thought as well.

Seems like this could be haxored together with some basic parts, maybe.

Am I correct to assume the chest does -not- have a hinge as shipped?

It looks like the parts list to make this happen are:

- Hinge
- L bracket to connect hinge to linkage
- Linkage down through the playfield slot
- Metal linkage to use as "seesaw" hooked to the fork mech, 2 holes 1 slot
- Basic lock nuts, nylon washers, spacers etc.

Unknowns at this point:

- Exact sizes/specs on the parts in question
- Are these customs, or can they be found in the wild somehow

EDIT: Maybe this will work? It claims to have holes -and- slots. https://www.lowes.com/pd/Hillman-0-094-ft-x-1-375-in-Plated-Steel-Slotted-Metal-Flat-Bar/3059253

See, I love this solution. What you crafted here is exactly what I hoped to get. Nothing against the OP but I like the simplicity - no additional switch/servo in the mix, and the action 100% synced with the fork mech. Violence on the bracket doesn't bother me, but I really would like to hear how/why this mech was abandoned. Specifically what the problem(s) were with it.

Also, did you take any video of it in action?

Here's the video for the steigerpijp linkage-based mod in action:

https://www.icloud.com/sharedalbum/#B11JqstnBJF1jPF

Looking very forward to this being productized!

I will absolutely buy this kit and sign up as a tester. It will get a lot of mileage in my house!

My thinking:

Servo: Motor will eventually give out, switch could fail. Two extra points of failure.
Linkage: Run off the coil which is electromagnetic and already firing anyway. Less to fail.

Maybe the issue with the chest wasn't the mech at all.

Maybe it was wear on the chest banging open and shut. I can see the paint wearing off of the prototype pics. Something we can mitigate with cabinet bumpers or something most likely.

Another possible reason for the chest nerf - maybe there was lack of consistency on the lids in terms of alignment with the chest?

Yes, you've made that clear.

I like the black hinge, it works better.

I'm still in for team Linkage, so the folks pursuing that route please don't stop.

I started the video to watch the chest action - which is great, well done!! - but then got interested in your score! Pretty good game there.

Idea/question: If I remember right (and it's possible I don't) there was already an EOS switch on the fork mech. Maybe it's possible to tap that instead of adding a second switch?

Thanks Jeremy for all the work you've done this mod!

Maybe we need a separate thread for it, but any updates on the linkage-based mod? This is still the route I want to go.

For those interested, it looks like shapeways.com can print the bracket in "versatile plastic" for around 50 bucks.

All this complexity is why I prefer the linkage-based solution steigerpijp was exploring.

We already have energy on the fork to raise/lower the lid.

I’ll get downvotes for this but I really hope that solution still comes to pass.

https://en.wikipedia.org/wiki/Feature_creep

Last I heard it is still being worked on and is undergoing extensive testing. That's the one I am holding out for.

harryhoudini I'm installing one of these for a local friend tomorrow. The only thing I am unclear on is the removal of the existing lid, does this require Pearl removal?

I must have missed it. I reviewed the install instruction videos which started with the parts and ended with the alternate rod setup. Did not see one for the initial chest disassembly?

Got it. Thanks! Looks easy enough.

https://pinside.com/pinball/forum/topic/jjpotc-treasure-chest-open-and-close/page/17#post-5186752

harryhoudini Ive installed the chest mod for cheshirefilms and it seems to work perfectly except the state is inverted. It closes when it should open and vice versa.

Does flashing the software fix this?

Thanks for this tip! That fixed us. The only other hicky was inconsistent operation at first, corrected with a slight bend to the switch arm.

The mod is cool!

It's a great mod. After seeing it in action, the game seems so broken without it.

We had some struggles with this too. If the chest does the open/close on boot properly, the issue is probably the arm to the microswitch. Make sure it closes and opens the switch in response to the forks being up and down, and bend the arm if needed.

I got the mod and installed it today. It works, but it’s a wee bit flaky. Sometimes, for example, it only opens the chest a crack.

Next open/close works as expected.

Is this a power issue?

EDIT: Hmm, seems to have stabilized out. If it gets flaky again I will try the string approach.

Also, I put some wire loom for the rod to travel through, which gives it a smooth plastic tunnel to operate in without chafing the playfield or other wires.

No lighting mod, but I would like it to close the chest faster...there is a delay between the forks going down and the chest closing that I'd like to reduce. Is that possible with the little remote button thing?

Well, I spoke too soon about it working itself out. I am getting regular failures now. Frequent but not 100%.

The symptoms:

- Chest opens only a sliver of what it should.
- When the chest closes, it rises to its full height, then closes.
- Sometimes on boot when it does the open-close thing, it doesn’t open all the way there either, making a whirring noise when it stalls.

I don’t think the linkage is binding, but I’ll check it again.

I’m assuming the bootup sequence doesn’t care about the state of the microswitch, so the control arm for that is unlikely to be the culprit. I am guessing this is a power issue and it doesn’t have enough power to pull it down.

Any suggestions?

I rechecked the rod and you were right, it was binding up. I bent it all back straight and started over, and now it seems fine. One clue that it was binding: the close operation was “choppy” previously and is now completely smooth.

Thanks for this mod, it seems to be completely reliable now and it really does add to the gameplay!

Yeah most likely the control arm for the switch on the mod needs to be bent to more reliably engage/disengage with the fork movement.

The chest mod responds to the fork position, so device test fork ought to work.