Author: Maker Block

Another interesting project – Tater Tot Gun

This is a project I stumbled across a few years ago.  It’s a “Tater Tot Gun” – a pneumatic gun which uses a small bike pump to pressurize a chamber and hold a semi-rigid diaphragm in place.  When the chamber is very slightly decompressed, the diaphragm falls out of place releasing all of the pressure and accelerating your projectile.  Apparently it’s capable of more than 350 ft/s versus 1000 ft/s for an actual firearm. If this project at all interests you, definitely check out the two or three different models he describes.

Bottom line:  it’s crazy dangerous.  So, naturally, I bought two mini-bike pumps.  I not going to be completing this any time soon. 1

  1. I bought those bike pumps about three years ago… [↩]

I would like to thank my agent…

…the Hollywood foreign press…

Actually, huge thanks to Dave Durant for the math and answering questions, Renosis for exhaustive testing and feedback.  Thanks also to all of the other beta testers of whom there are too many to name.  Um, they’re playing the music,…  uh, uh, Honey – we did it!  Um…  Free Tibet!  and… um…  I’m King of the World1 !!!

—

In seriousness, since the launch of the first ProfileMaker v1.0 less than a week ago there have been 152 profile settings generated and the beta testers generated 270 profile settings through ProfileMaker v2.0.  Version 2.0 incorporates many of the things mentioned in the recent poll. 2  Here are some of those improvements:

  • ABS as well as PLA
  • Works with 1.75 and 3mm or any filament diameter you choose
  • Ability to change the feedrate, the mysterious gear swell, and gear diameter

I’ve already begun work on ProfileMaker 3.0.  If you want to help as a beta tester, or get the math involved, or want to help kick the tires of the user interface please drop me a line or leave a comment.

  1. of web based 3D printing calculators that solve for flowrate for stepper extruders [↩]
  2. Still active as of right now – but get your votes in if you want to let your voice be heard [↩]

Dear Movie Studios… would you like to borrow my glasses?

…’cause you are apparently as nearsighted as I am.

I netflix’d the movie Scott Pilgrim vs. The World a few weeks ago.  It was pretty entertaining.  I don’t often check out the “special” features on movies, but I went to that menu option after watching the movie.  In doing so the DVD notified me that the disc contained only the movie itself – but that I should purchase the DVD myself to watch the extras.

Here’s the thing.  I don’t want to buy your movie.  I’m never going to want to buy your movie.  It was good, not great.  But, really, that’s why I have Netflix.  I’m not going out to invest $20 in your movie and then have another DVD case clutter my life.  I’ve already paid for the privilege of watching your movie – I’m not going to run out and pay $20 (or more) on top of that to watch 15 minutes of people screwing up their lines.

Let’s look at this from a wider perspective.  The sorts of people who are willing to pirate a movie don’t really care overmuch about the DVD extras – they’re content to watch the main movie.  So, now you’ve created a system where the people who are actually paying for the privilege of watching your movie are getting the same content they’d see if they pirated the movie??  Shouldn’t you be doing the opposite?!  Doesn’t it make more sense to add more content to DVD’s, not less?  Why not make the actual DVD so incredibly enticing with extra features that those people who would normally pirate a film want to either (a) Netflix it or (b) buy it?  I mean, it’s not like the Netflix business model is going anywhere.  They’ve only gotten bigger in the last ten years and basically put brick-and-mortar movie rentals out of business.

Anyhow, for all you film execs who closely hang all over my every word – if the film industry wants my $20 directly, here’s what they have to do:  Make a movie so freaking awesome I’m going to want to watch it again – and soon.

ProfileMaker Version 2.0 is coming!

A few cosmetic details to work out yet…  but I’m almost ready to launch the second version of my ProfileMaker.  I released the first version late last night.

I’d like to think that I’ve increased the number of options while still keeping a slim and intuitive user interface.  I would really appreciate any comments, criticisms, or questions you may have.

ProfileMaker thoughts…

Looking at Dave’s Profileinator seems really well suited to a stepper extruder.  However, he also suggests adding a “Flow Fudge Factor.”  I just use this set to 1.0, so I’m not sure if I’m using it correctly.

Flow Fudge Factor: I have to enter 1.0 into the flow rate to get 2.0 RPMs on the extruder.. I got tired of doing this math so I added flow fudge factor and set it to 0.5. This doesn’t change the volume calculations – it just modifies the flow rate on the table. If you have a MK4/MK5 extruder with a DC motor, start this at 127.5 to get the PWM value to use

In any case, it looks like by multiplying it by 127.5 you can get the required flowrate for a DC motor.  In printing with a DC motor, I never wanted to drop the speed below 255, because the DC motor had such a small range of speeds.  I could print between about 230 – 255.  Given this, I can understand why so many others, probably using a DC motor, would rather pick their flowrate as 255 and then determine the proper feedrates.

Cross-Platform Profileinator Web App

Some of this write up is over at Thingiverse and some of it is at the end of the ProfileMaker page.

Dave Durant’s program for solving for flowrate is really incredibly helpful.  It is truly a shame that it isn’t more widely used.  I think part of the problem might have been people were intimidated by all the buttons and part of the problem was that it was a Windows only application.  There has since been a port to Java, but that’s not as convenient as a truly web based version.

I’ve hard coded the most common options, but fully intend to bring them back later as advanced options.  For now I just wanted to whip something together to help people out and show them just how easy calibration can really be.  Give it a shot.  If you haven’t printed at 0.2mm layers before, give it a whirl!

I’m really really looking forward to being able to enter values into Skeinforge from my cell phone.

Your suggestions, comments, questions, criticism, e-mails, etc are all welcome and invited.