Tuesday, November 15, 2016

slowly ramping up again

So it's been a couple weeks since my dog had his checkup from the doctor, and he seems to be 80% back to normal (once the other dog decided to play, and when he twisted his neck around he yelped loud).  Even the doctor said it might be a few more months before his neck muscles are completely healed, but at least the "don't let him jump and watch his every move" phase is over with.

So in the meantime, besides printing some jobs to earn money, I HAVE been working on the layout in CAD, and doing more tweaks on 3d printed mechanisms.  The trough and apron are simplified, and closer to a standard apron shape.  I'm also trying to make the cuts very basic and simple (so anyone with a jigsaw can make their cuts fast and easy), and so long as you have your 3d printed parts ready, you can make all your cuts, bolt all your parts onto the plywood, and have a lower end built in about 30 minutes (minus wiring).

I was struggling for a while where to put the VUK to bring the ball back up from the lower playfield, but I think I have it figured out.  There's going to be a lane just above the trough that will allow the ball to sneak back in without the player seeing what's going on.  Honestly my end goal is to potentially 3d print everything (so long as it will hold up).  I have a sling mechanism modeled up that I think would work quite well, and it would only require you to drill a couple 1/2" holes to mount it, plus the two 1/2" holes for the switches (again, make the cuts as easy as the mechs themselves).

There's this video recently of a guy that supposedly completely 3d printed a pinball machine (playfield, pop bumpers, flipper mechs, EVERYTHING).
https://www.youtube.com/watch?v=NKl3aX-tyLY

I'll admit it's impressive, but the flippers are weak, and I didn't see the slings fire once (but the pop bumpers seemed to work well).  Problem is, that guy will never share his files, so that project dies with him.  My intent is to eventually get all of this on pinballmakers.com so anyone can jump in.

Sunday, September 11, 2016

May be on hiatus again for 4-6 weeks

One of my dogs has been slowly been showing signs of age.  I'm kicking myself for not looking into insurance, but yesterday it got at it's worse.  He suddenly couldn't put any weight on his front right foot which freaked me out.  To top it off, my wife is out of town for work until this morning.  Anyway long story short, he had disc surgery last night which went very well but he's going to have to rest for the next 4-6 weeks (which means either crate, but I know he'll cry), or sitting with him making sure he doesn't try to jump.

Now granted, I may still be able to work on the layout on the computer, or model stuff in solidworks, but fabrication is likely not going to happen for a while since he'll need my attention.  My wife will likely take turns, but I just know leaving her alone with the dog probably isn't going to happen.

Sunday, September 4, 2016

New loop ramp tested

So on the latest, I didn't do an ellipse but I did add a chamfer to keep the ball centered (and curved the transition in better).  Did a quick test with the flipper..


Good: It's pretty consistent in being able to make the shot and have it loop around
Bad: I assumed there would always be enough speed for the ball to clear the ramp.. at least a few times the ball was too slow and it sat there at the end of the exit... stuck.  My solution is going to be to make the entry and exit a ramp (at least a 10-15 degree incline).  That way even if the ball drops right at the end of either side of the corkscrew, there will still be enough gravity to make the ball exit.

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!