Quoted from johnndeanna:Hello all,
I wanted to see what everyone thought would be the base minimum needed to get flipping on a basic whitewood to start testing shots. I am planning on going with the P3-ROC and associated boards for the build but wanted to get going on a basic whitewood to make sure shots work and it flows well. I am mainly focused on the lower playfield and am assuming the following:
- flipper assembly left and right with coils
- Slingshots
- 48V power supply
- flipper buttons
- wiring as needed
For the upper playfield I already have a bunch of posts, standups and rubbers. I figured I don't need the boards yet since I am just testing shot layout. Your opinions are welcome as to anything I am missing.
John
Fort Mill, SC
Hey John,
Congrats on taking the leap into custom pinball design. A few insights that might help:
1. Your flipper situation will depend largely on what coils you end up using (single wound or dual wound). The P3-ROC and its associated driver boards can handle either situation, but it does affect the EOS. In older systems, the EOS was responsible for switching the high power coil to the lower power hold coil in a dual wound system. At this point in time, the power was directly switched through the flipper switch, and you had giant "snubbers" on the flippers themselves to reduce the arc.
Nowadays, the power is switched on the driver board using MOSFET transistors. We only use the EOS to re-energize the coil throw in the event that the flipper bat gets knocked down. This also prevents a broken EOS from burning out a coil or a MOSFET. If you use a dual wound coil, your software should automatically engage the hold coil after pulsing the main coil. If using a single wound coil, your software will do what we call a "pulse patter" which will throw a strong pulse in and then engage in PWM to hold the flipper up. The EOS in this case is only responsible for telling the software to re-engage the flipper if a high speed ball knocks the bat down. Dual wound coils will use 2 transistors on the driver board per flipper, single wound coils will use 1 transistor per flipper.
It really is six of one and half-dozen of the other.
2. Slingshots - Get the all-in-one piece that Stern/Pinball Life sells. You'll be thankful to not have to deal with alignment issues.
3. 48V power supply - Most of us use meanwell power supplies at 48V. It's more than enough juice for the flippers, but you will need charging caps to smooth out the power flow because flippers need a lot of sudden inrush current available. You will also want an ATX power supply available with various 3.3, 5 and 12VDC available. This will power your boards, optos, etc and is helpful for having "general power" available to other sections of the playfield.
4. Wiring - Get multiple colors of wire, use 18GA for your flippers and 22GA for your switches. A few different colored Sharpies and a large roll of white wire is more than enough for what you need.
5. CONNECT YOUR GROUNDS. Make sure your lower power grounds and your higher power grounds are connected. Failure to do so will almost inevitably result in blown boards.
6. Test incrementally as you go along. Test a few switches first, test a lower power coil, etc before you wire the whole thing up.
7. Software - Do some homework ahead of time. If you're not really the "programmer type", most people lean towards MPF. They've got solid docs and a well-defined installation process on major platforms. Get that set up and tinker around beforehand so you're not fighting software AND hardware issues at the same time. Don't plunge into a full out computer build just yet, just toss the software for testing on a laptop, you don't need a ton of horsepower yet.
Overall, this entire thing is about setting yourself up for small incremental wins. Doing this, as you undoubtedly know, takes a lot of work and a lot of trial-and-error in various areas. Doing things in manageable stages will give you the dopamine rush that comes with getting your first switch events working, or getting those first flips that don't blow fuses. Ultimately, those little wins will power you into getting a game built and fully playable.
Looking forward to see what you cook up!
-- Jimmy