What's new
By:
Pinball info

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

In Progress Mishmash Homebrew - Pt II - Playable Coffee Table

Boring update.

Going to need to make a power filter board as I now have the playfield at an honest 6.5 degrees which shows the 24v power supply dropping out on the outhole and flippers.

I plan to take advantage of the power filter board here:

OPP - Pinball Makers

pinballmakers.com pinballmakers.com

I may need to upgrade to a 48v PSU but I'll hold off until it's all built. 24v is fine for testing and perfect for my chimes.

The ATX PSU is mounted now and that gives me 12v for the shaker motor.

A 2004A LCD display came today which will offer a small makeshift score display mounter above the playfield apron for the time being.
 
Quick update. I got a set of Bally chimes from pinparts.co.uk. Connected these up to one of Alan's original MOFSET driver boards and just hacked in some code to fire one of the chime solenoid every time points are scored.

17238168744087923756152335398358.webp


God I love pinball chimes, but everyone else thinks it's a doorbell. Oh well 😅

 
As there is a lot of cosmetic work to do on the body, but I still want to work on the game I have been struggling with how to connect the cabinet buttons.

For now, a few 3d printed button holders with Sanwa type 30mm buttons should do the trick.
 

Attachments

  • IMG_20240818_144822177_HDR.webp
    IMG_20240818_144822177_HDR.webp
    116.3 KB · Views: 5
As there is a lot of cosmetic work to do on the body, but I still want to work on the game I have been struggling with how to connect the cabinet buttons.

The wrong hole in the wrong place could make things tricky later on.

For now, a few 3d printed button holders with Sawna type 30mm buttons should do the trick.
IMG_20240818_144822177_HDR.webp
IMG_20240818_145629774_HDR.webp
 
48v PSU arrived today. Tried for a few mins this evening. Wow, what a difference!!!

Unfortunately the flipper board I made was the same batch as the solenoid boards I made and found were useless. The issue was I failed to make the earth trace big enough to handle the load. Smoke stopped play 😁😁😁

Time to get editing and ordering from jlcpcb.

IMG_20240820_160149798~2.webp
 
Ashbo said:
48v PSU arrived today. Tried for a few mins this evening. Wow, what a difference!!!

Unfortunately the flipper board I made was the same batch as the solenoid boards I made and found were useless. The issue was I failed to make the earth trace big enough to handle the load. Smoke stopped play 😁😁😁

Time to get editing and ordering from jlcpcb.

View attachment 259178
Click to expand...
Ah fuseable traces 🤣


It's only a protptype, just solder some wire across the back of the board on the current carrying traces so you can carry on testing 👍
 
lukewells said:
Ah fuseable traces 🤣


It's only a protptype, just solder some wire across the back of the board on the current carrying traces so you can carry on testing 👍
Click to expand...
Nice, yup that worked thanks 🙏 I'll be ordering a new prototype, my nerves can't stand the hidden wires under the boards 😅😅
 
The latest flipper board design was delivered today. It would be rude not to give it a go.

IMG_20240828_170455663.webp
IMG_20240828_170505452.webp

First attempt ended in a blown MOSFET and some head scratching. It seems the higher voltage was arcing to connectors I wasn't expecting. Added some insulation and that solved that


The power from the new Meanwell 48v 350W PSU is impressive.

 
Dull update. I was measuring voltage out of the PSU (after adjusting output from 48v to 43v ) whilst operating the flippers and was concerned that there was no voltage drop seen when multiple playfield coils were fired and none for the left flipper, but when the right flipper was actuated the drop was clearly visible on a multimeter. I looked like 10v drip for a half second press. Pushing my luck I held the right button in and after a second or so the PSU shut off.

It didn't come back on a concerned few moments passed. Had I blown my MOFSETs again??

Turning of the mains for a minute and then turning back on again and we were back in business.

I was able to hold the left flipper for ever with no voltage drop and a quick tap on the right saw a drop again. A hold, and off goes the PSU. There must be a short somewhere causing the PSU to cut out. I remember in Alan's blog he even had to change the eos switch because his 44v PSU kept quitting. Same fault different error this time, eos switches are perfect.

I've had a look at the coils and it seems we have less that 2 ohms on both windings on the upper flipper which surely isn't right. It's much less that the other coils (off the top of my head about 80 and 4 ish).

A couple of replacements ordered off eBay. Why is every pin a money pit???

IMG_20240829_192103701_HDR.webp
 
You could put in modern flipper mechs and use two mosfet outs - one for hold and one for the kick. Then a low voltage EOS would need to be used.

I also see a lot of people use the wrong EOS switches.
 
Pick Holder said:
You could put in modern flipper mechs and use two mosfet outs - one for hold and one for the kick. Then a low voltage EOS would need to be used.

I also see a lot of people use the wrong EOS switches.
Click to expand...
Thanks mate

Deffo could be a way to go. A small microprocessor controlling an initial full power bust to the flipper using a MOSFET then moving to PWM for the hold. Would make things much simpler and safer.

My initial concerns were doing this through the esp32, we are taking up GPIO pins which can be ill afforded to be given up. But a simple esp8266 could handle this on a stand alone flipper board. It could even send out flipper button events to the esp32 via dedicated io, or serial or even WiFi (perhaps too much latency).
 
Just add some 595 Shift registers to expand your gpio pins - or a dedicated SPI i/o expander like the MCP23016

Personally I've always used the shift registers cost they are cheap and easy to use. I will get round to using an MCP23016 or similar at some stage in the future though, just for the hell of it.
 
AlanJ said:
Just add some 595 Shift registers to expand your gpio pins - or a dedicated SPI i/o expander like the MCP23016

Personally I've always used the shift registers cost they are cheap and easy to use. I will get round to using an MCP23016 or similar at some stage in the future though, just for the hell of it.
Click to expand...
Did think about the shift, however (in my head) getting around coding the PWM control seemed overkill when a dedicated pin could bo it natively.

All academic at the moment because I'm not investing in any new flipper mechs any time soon, unless I win the pools ;)

It's good theory though, for a much more reliable pinball experience
 
Ashbo said:
Did think about the shift, however (in my head) getting around coding the PWM control seemed overkill when a dedicated pin could bo it natively.

All academic at the moment because I'm not investing in any new flipper mechs any time soon, unless I win the pools ;)

It's good theory though, for a much more reliable pinball experience
Click to expand...
Yes, agree I'd always use a dedicated pin for PWM, and all other I/O can go via the Shift Registers / I/O expanders.
 
You must log in or register to reply here.
Back
Top Bottom