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Author Topic: Team AstroBot  (Read 7058 times)

Lucas Grell

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Re: Team AstroBot
« Reply #15 on: March 04, 2015, 12:25:47 pm »
http://www.practicalmachinist.com/vb/general-archive/casting-urethane-pallet-jack-wheel-80177/ This thread has some good ideas and suggestions, maybe something in here could give you a good starting point.
Sounds like if you do it, you'll want to have a ton of molds made up so you can use all of your polyurethane in one go, maybe some PVC piping cut up glued to a plastic sheet with holes drilled to center the wheel cores? Sounds like a cool project, hopefully this helps some.

TeamAstroBot

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Re: Team AstroBot
« Reply #16 on: March 04, 2015, 12:46:08 pm »
http://www.practicalmachinist.com/vb/general-archive/casting-urethane-pallet-jack-wheel-80177/ This thread has some good ideas and suggestions, maybe something in here could give you a good starting point.
Sounds like if you do it, you'll want to have a ton of molds made up so you can use all of your polyurethane in one go, maybe some PVC piping cut up glued to a plastic sheet with holes drilled to center the wheel cores? Sounds like a cool project, hopefully this helps some.

Thanks! I will look down through the thread in a bit.

In the mean time, I have been looking at this product (http://www.smooth-on.com/Urethane-Rubber-an/c6_1117_1407/index.html?osCsid=rmjppovq52cs0m0voncsmb8767) for a long time now, and may finally pull the trigger on it. As far as the molds go I was thinking about just 3D printing them and using a release agent to get them apart once they cure.

Lucas Grell

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Re: Team AstroBot
« Reply #17 on: March 04, 2015, 12:54:07 pm »
3D printed molds would work, but how exactly does this release agent work? Would it remove all the outside plastic, or something like that? If not, the small ridges on the plastic after the printer (although it does depend on how nice those parts come out, hard to tell in pictures) might make it hard to remove from the mold, considering they'd be pressed into all the folds.

teamsandman

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Re: Team AstroBot
« Reply #18 on: March 05, 2015, 08:36:05 am »
If you 3D printed them with a small enough amount of material, you could consider them disposable and break them off afterwards.

TeamAstroBot

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Re: Team AstroBot
« Reply #19 on: March 05, 2015, 09:11:50 am »
If you 3D printed them with a small enough amount of material, you could consider them disposable and break them off afterwards.

I'm thinking about a 3D printed, hinged mold. Place the  wheel hub in the center, close the outer mold around the core and then pour the compound. To release the part, open the mold and gently pull.

(it sounds very easy in my head, but I'm sure it will provide a challenge somewhere.)

The biggest setback I am seeing is that it is either really expensive for a small amount, or you have to purchase bulk qty which is equally as expensive.

TeamAstroBot

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Re: Team AstroBot
« Reply #20 on: March 07, 2015, 09:06:01 am »
So, seeing as my go-to Beetle drive motors (kitbots 1k rpm) are currently back ordered, what is everyones opinion of the Silver Spark gearmotors in a Beetle application? Primarily for use in a VS.

MikeNCR

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Re: Team AstroBot
« Reply #21 on: March 07, 2015, 01:47:09 pm »
So, seeing as my go-to Beetle drive motors (kitbots 1k rpm) are currently back ordered, what is everyones opinion of the Silver Spark gearmotors in a Beetle application? Primarily for use in a VS.

I'd suggest looking at the belt drive setup Jamison uses ( http://sparc.tools/forum/index.php?topic=71.0 ) on his small bots. That'll help the 3mm shaft survive the 3lb class and is still a fairly lightweight setup. The sparks can move a 3lb bot well enough, but the 3mm shaft is a bit fragile for direct drive.

zacodonnell

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Re: Team AstroBot
« Reply #22 on: March 07, 2015, 02:21:24 pm »
Mike, do you mean with the motor in the middle with two belts - one to the front and a separate one to the back?  Do you think the spark motors are going to have the torque required to turn a 4wd 3 pound bot?

DDT seems to have bigger axles than typical in that class, indicating that he is driving it not on the motor shaft.  I can't seem to find an internal picture that shows the way it is set up.

-Zac

MikeNCR

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Re: Team AstroBot
« Reply #23 on: March 07, 2015, 02:39:45 pm »
I'm talking about the setup on DDT and Silent Spring. I've got a shot of DDT from Dragon Con that shows it decently well-

zacodonnell

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Re: Team AstroBot
« Reply #24 on: March 07, 2015, 02:59:28 pm »
Ah, I didn't see that in the pictures on his site. 

As an added bonus, this allows you to position the wheels in a good place for the center of gravity so they get better traction.

-Zac

Koolaid64

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Re: Team AstroBot
« Reply #25 on: March 07, 2015, 08:54:15 pm »
this is how dick dastardly is set up to

TeamAstroBot

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Re: Team AstroBot
« Reply #26 on: June 25, 2015, 07:45:25 am »
Just going to leave this here.




Lucas Grell

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Re: Team AstroBot
« Reply #27 on: June 25, 2015, 02:46:09 pm »
Wedge?

satacoy

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Re: Team AstroBot
« Reply #28 on: June 25, 2015, 03:22:40 pm »
They're beautiful, whatever they are.

Badnik96

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Re: Team AstroBot
« Reply #29 on: June 25, 2015, 09:44:38 pm »
Those are some tasty wedgelets. Aluminum I assume?
TEAM IGNITION
FireArrow (Antweight) 23-11
Nocturne (Beetleweight) 5-10 (Retired)
KnightShade (Beetleweight) 0-0
Landshark (Mantis) 1-2

Pennbots 2014 and Bot Blast 2014 antweight champion. Bot Blast 2013 Best Driver and antweight third place.