Tuesday, August 30, 2016

What made Williams Pinball good?

I'd like to think there's something to titles on Williams being more memorable than some of the modern pinball, particuarly Stern.  As Gary says, they are making "modern retro pinball", and it couldn't be truer.  They really are building retro pinball with a modern twist.  What do I mean by that?  Most of their titles have everything above the playfield.  There are no hidden doors, no mechs that pop out from the playfield, no subway tunnels.  I know this is done partly for reliability, but I know cost reduction and ease of assembly / disassembly also plays a part.

A lot of things were hidden on Williams.  You had a moving gun on T2, Shaker motor on earthshaker, spinning fan topper and spinning discs on whirlwind, mist multiball on BSD, adams family hand that pops out, twilight zone magnet flippers, funhouse toy that came alive.  Every time a new title came out, you wanted to play those games just to see what hidden features you'd discover, sort of like playing a miniature golf course for the first time (at least ones with tunnels that lead your ball to a random spot on another place on the green).

I'd like to implement some of that magic into my revision 2 layout.  What happens when I shoot the ball up this lane?  A hole just got revealed, where the ball go from here?  I just saw it pop out, but where did it come from?  That ramp looks different, what's the ball going to do when I shoot it up there?

Thursday, August 25, 2016

loop ramp 3d printed, it's better?

Still getting some ricocheting effect, which could be due to not having a fillet transition from the flared opening into the corkscrew.  It makes the loop about half the time, but it may be less than that when trying to aim for it with a flipper (I should temporarily mount it and try).  I think I'm going to make some tweaks and print another one tomorrow.  I think the roughness of the print may be slowing the ball down too, which could be easily remedied by adding a strip of steel that follows the path all the way through. to smooth it out.

Here's a quick video:
https://youtu.be/9U7YGLaGbpI

Wednesday, August 24, 2016

remember that loop-da-loop ramp?

I may have talked about this in an old post.. turns out to keep centrifical force constant, a loop is not circular, but rather an ellipse:
http://gizmodo.com/why-roller-coaster-loops-are-never-circular-1549063718

This is mostly done for the purpose of reducing g's on the human body.  I figure if you're talking about a pinball with constant velocity (IE: same force holding it against the ramp as it goes around), this is also ideal.  If the force changes, that could be what makes it >pop< out of the track.

SO!  Now that 3d printed pinball parts are popping out of my machine, it's time to revisit that concept in PLA.  So let's look at the loop ramp I started before:
From the side, it's a perfect circle:
We want an ellipse.  But how to model that?  Solidworks can model screws of all kinds, but they are based on a round shape.  I found one complicated tutorial of how to create something, but then  I found an easy out.  Take my existing shape, and use the scale command but only in the Y-axis:




Going to print it tonight since it's a 4.5 hour job even on fast speed.  I'm going to try to print as a single piece without support.  In theory because of it's shape it should be self supporting.


Wednesday, August 17, 2016

3d printed ramp

Getting a 3d printer (especially once you've dialed it in) can be quite liberating.  No longer are you fumbling around for "how the hell am I going to fabricate that?!", so long as you have solid modeling skills.  So for grins, I decided to model up a simple straight test ramp.  Basically a v-shape, cut out the bottom to save material and build time (since the ball only contacts in the middle), not to mention create an opening so it doesn't block the playfield so much.  Add 2 bosses on each side so I can connect multiple ramps together (my build plate is only 6"x9"), and realistically there's no limit to what I can build.  Did a test print last night, and it worked NICE!  I mean it's smooth, smooth like the monorail ramp on simpsons pinball party (just as I expected).


I just used some self tapping screws I had lying around (had to drill clearance holes on one side), but it's a pretty solid structure.  If I were doing real ramps, I'd probably use brass inserts and machine screws so it can be taken apart over and over (and probably an even better joint).

So now I can basically model my waterfall ramp just how I want it, make a cut every 6", add bosses, and print each section then join them all together.  I will get exactly the ramp I want without complicated metal fabrication.  Each ramp section costs me 84 cents to print!


Sunday, August 7, 2016

3d printed parts made, plywood cut, assemble time

So I finished printing my parts, I cut my plywood with basic tools (a 1/2" spade bit and a basic jigsaw).

My intention is to make starting a playfield (lower end) quick and easy.  I don't have a coil mounted to the bottom of the trough yet (soon), but from a geometry and structure standpoint it worked out fairly well.  A few things:
1. Holes need more clearnace than you think.  For whatever reason 3d printers suck at making holes, they are always smaller (shrinkage?).  And since by default slicers fill the inside with a grid instead of solid material you want to make sure your holes are sized appropriately
2. Try to make as few pieces as possible that will still fit in your printer.  I MAY be able to make the trough as one piece to simplify alignment.
3. Always make sure you have mounting holes for everything.  In my rush, I neglected to add mounting holes for the shooter lane part.

Considering I printed everything without support and the fastest speed, it turned out pretty well.  I think if I ran parts at medium speed, I'd get better quality.

To see a quick video, click below:
https://youtu.be/61cx1U71XZU

Saturday, August 6, 2016

3d print design progressing

So I've added walls, an updated shooter lane, a wall to prevent the ball from popping out of the shooter lane (but allow a plunger to go through).  I've also split the trough into 2 pieces.  The entry ramp goes up to the surface so the ball doesn't drop and wear out the edge of the playfield.  This dumps into a main trough.  I've got everything 3d printed but the 2 left walls (which I just finished modeling).  If you're curious why some walls are split up, it's because my 3d printer platform is 6" x 9" (as most are unless you have a TAZ printer which is only marginally larger).  I'm going to cut plywood tomorrow, and only 10" of height because I have a scrap piece of wood I don't mind using to test out proof of concept.  I also need to buy some 1/4" x 1" balsa strips for the side rails.  I know typically 1/2" is used, but I think using #6 wood screws that 1/4" should still work for walls and conserve space.