Rarry the Crab-Monster

[zorlack]

Ok, so I'm still learning the in's and out's of 3D machining. Since I work in theatrical scenery, mostly what I'm learning about is the fastest possible way for me to machine something out of pink/blue foam.

On this particular Saturday afternoon I had my friend, Max, draw up a little crab monster - which I then extruded into 3D using Artcam. The result, is Rarry.


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Ok, so maybe Rarry's not the coolest thing ever. But I learned some interesting things. Like, for example: It's way faster to machine foam with a .1" stepover and then sand it after then it is to to use a .03" stepover. This isn't a universal principal, but for theater it works pretty well. Also, my bot had no chatter issues cutting at 3IPS and plunging at 2.5IPS. So that's good to know. I think I could probably get the cutting time down a bit if I tweaked the ramping values, but that's too much to play with in one day.

The piece took 15 minutes to do the Z-Roughing, and 45 minutes to do the finish pass. If I had a ballnose cutter with a 2" LOC, I wouldn't have even needed to do the rough pass.

Rarry's designer (http://www.flickr.com/photos/zorlack/2931959259/in/photostream/)

[myxpykalix]

What do you mean..Rarry's not cool...he's WAY cool!

[pfulghum]

Way cool.. Can I order 10.

Is he "flat" on the back side (2.5D) or machined both sides?

Is the material HDPF (aka Home Depot Pink Foam)?

What's it like sanding pink foam?

-- pat

[zorlack]

Hehe Thanks Pat and Jack!

Yeah, Rarry is one-sided, but he's got that can-do attitude... so that's a bonus.

Yeah, we cut him out of a piece of foamular. It sands very easily, features are a bit tougher, but oh well, what are you gonna do.

In the time it takes to sand the bot, could get started on the second one!

A friend uploaded a video (http://flickr.com/photos/thereisanothermoei/2936668868/) of the process.

[zorlack]

So, if anyone wants to make a Rarry of their own.


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Here's the source! (http://zorlack.com/design/cnc/#rarry).

Rarry is licensed under the Creative Commons Attribution-Share Alike 3.0. Just so there's no confusion ;-)

[rick_woodward]

it just so happens I am going to use pink foam for a project. I am looking for a thin sprayable hard coat of some kind. I am also going to try just painting it with latex paint to see if that works. Got any advice ? Looks great. Thanks, rick woodward

[gene]

What software did you use and what was the cut speed ? That has to be too much fun creating stuff like that. Thanks Gene

[zorlack]

Rick, Thanks! I don't have much help for you in terms of sprayable coatings. Though do let me know if you find one (this subject is my white whale). Latex paint will definately help seal it, but its not going to add much hardness. In the past I've used latex paint, heavily fortified with white glue. That helps a bit... but it isn't very sprayable. If you want an infinitely durable weather-proof coating, Google "Jaxsan". That stuff is amazing, but its a pain to apply.

Gene, Yeah, we had a blast playing around
. We drew the lines in Illustrator. We then did the 3D work and the toolpathing in Artcam. I have an older Shopbot PRT with a router. On my setup, I had the XY speed at 4 inches per second and the Z speed at 3 inches per second. I used a 1/4" roundnose bit with a 1" cutting length.

-Dave

[knight_toolworks]

I have to make this for my crabby daughter. can anyone convert it to a format cut3d can use?

[gpari]

Steve, If no one beats me to it, I'll give it a shot in the morning.

Gabe

[knight_toolworks]

got it. this is perfect for her. she is a grumpy 19 year old and terrible in the morning.
Now I need some foam so I can make it large.

[myxpykalix]

Steve,
As a kid growing up one of my friends mother taped a cartoon on his bedroom door and i recall it to this day and it may be an appropriate little plaque you can carve with rarry.
It was a picture of a kid all disheveled with a scowl on his face and the caption read "Why is everyone so grumpy when I wake up?"

[sailfl]

Dave,

It is very nice of you to share your creation. Thank you

[zorlack]

Thanks, Nils!

Ooh! This is exciting! If anyone ends up making one, post a pic!


-Dave

[knight_toolworks]

just cut it out and put primer on him.

[knight_toolworks]

I made him out of mdf.


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[zorlack]

Hahah Awesome!

[pfulghum]

OK...Rarry was just too scary for my liking so I made "Harry" (and Harry Jr) the Happy Crab Monsters


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Here they are guarding the shop.

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And a close up of Harry Sr. (He needed some help holding the axe).

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They are made out of LBF.
My thought was to use try some Apoxie Paste and then my daughter will paint with Acrylic Craft paint. Just in time for Halloween.

-- Pat Fulghum

[zorlack]

Nice!

[lstovall]

Hey Pat, those are great. Nice work.

[pfulghum]

Thanks all...

p.s. You will notice that Harry Sr. has bigger arms. I was really scared that Harry Jr.'s arm would break.
-- pat

[zorlack]

Steve, how thick is the MDF you used for yours?

-D

[knight_toolworks]

I glued up two pieces of 3/4" but then I added a piece of 1/4" after it was cut to give the arms some support.

[mitch_prest]

G'day Pat..

any chance you could post the files for your crabs.. those are less likely to scare little ones..
Mitch

[procarve]

hard spraycoating for pink or blue foam

http://www.smooth-on.com/index.php?cPath=1287