SpudTech Archive

by **Navigator7** » Sat Nov 18, 2006 11:10 pm

I've shoved lots of potatoes down barrels and have become quite bored with the task.
A quality projectile that is easy and cheap is where it's at....IMHO.

I'm three knuckles deep into making a huge business decision!!!!
I'm considering buying a rapid prototype machine for fun and profit.
(Actually a 3D printer and 3D scanner)

Plaster projectiles are by far the funnest projectiles I have shot...but what a pain in the arse to make.... The impact makes it all worth while....sorta.

The machine I'm on the edge of purchasing could fabricate molds for making custom shaped projectiles for every PVC barrel size out there up to about 6"

Taken it a step further......wouldn't it be the shit if your projectile screamed like a spoiled brat being punished by Mom in front of his peers.....right up to the point of impact??? Ka Pooooow~!

My question is....anybody interested in custom molds so you could make your own perfect ammo for your cannon? Not one at a time but many. Custom shapes that would even offer directional fins and optimal ballistic shapes?

I am.

I'm so freaking flipped out about the prospect of designing the perfect shape for a smooth bore barrel and coming up with an insanely easy way to create molds....I can hardly stand it.

I need some enthusiastic support. How about it?

by **crashtestdummy** » Sat Nov 18, 2006 11:15 pm

PROJECTILE MOLDS!!!!11!

lol, I'd buy a bunch depending on how much the pricing is. That's an awesome idea, because then you could make several plaster projectiles overnight and then open the molds the next day and have a bunch of them. What do you think would be the pricing, if you have got to that point yet?

by **Navigator7** » Sat Nov 18, 2006 11:41 pm

It's business.
One is expensive.
Two costs less, three is better yet and so on.
My build area is 10 x 14 x 8" high.

The molds would be re-usable.

I do know I could make one mold for 12ea, 2.87 Diameter projectiles for schd 80 3" barrels that would be about 6-7" long each.

Whistle holes built in.

What I am looking for is interest.
If the consensus here came up with a killer shape ...and I come up with a machine that can produces the mold.....and performance and accuracy are proved out.....plus the spectacular impact of a plaster projectile...(always a crowd pleaser).....who wouldn't want a mold?

The other way to do this is sell a positive with runners...so the business oriented guy could make as many projectiles as he had room for and plaster??

Thoughts?

by **aetherguy881** » Sun Nov 19, 2006 12:09 am

It does sound very intriguing (sp?) although I'd haveto fix my cannon, or just build another one. come to think of it I should. I'll gladly buy once I get some money.

by **SpudStuff** » Sun Nov 19, 2006 1:47 am

Would you be ablo to make other things like pistona ad complicated parts if we provided you with a file?

by **Navigator7** » Sun Nov 19, 2006 11:38 am

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by SpudStuff
[br]Would you be able to make other things like pistons and complicated parts if we provided you with a file?
<hr height="1" noshade id="quote"></blockquote id="quote">

Yes...but making a piston, for example, would be an absurd use of the technology and a waste of the $component material$ used to build the model.
Turning a piece of ABS, UHMW etc., makes way more sense.

Complicated parts is where I can compete with a lathe, mill and/or CNC machining.

A few ideas I have are:

o Inserts over the ends of PVC pipe that smooth the flow of air and eliminate sonic choking for higher air flows.
o Molds for member designed QEV valves....specifically built for launching projectiles.
o Projectiles of unlimited design potential. (My future vision is launching a projectile that becomes like a cruise missile and then is controllable to it's destination) A recent thread about $39.00 piezio helicopters means the technology is already here.
o Piston seal add ons that would allow low pilot pressure differential to make the valve dump better. I think they are also called pop off valves.
o Intricate parts needed for say semi-auto...piloted spools and so forth.....

I'm still learning about the material available for part making.
There are five products.
The lowest strength is an elastomer at about 2MPA..... but is very flexible....which has tons of uses.
The highest strength is is 60 MPa at 2% strain. (Concrete is about 20 MPa)
It might be suggested this is also brittle?
I haven't been able to determine if the product can hold pressure.
Aluminum is three or more times as strong.

Molds can be made to produce brass or aluminum castings. These are one use only molds as they are destroyed retrieving the part.

Re-useable molds can be made for the injection of resins, epoxy, plastic, rubber as well as ....projectiles.

Cores in molds usually stop even the most motivated. It's a friggen bitch to make patterns anyway never mind making a core.
o You need to make a cope and drag,
o buy sand,
o make the pattern...
o make the runners
o make the gates
o make the risers
o make the chokes and filters if needed
o make the sprues
o Include vents
o Allow for shrinkage
o Allow draft angle for removal of the pattern
o or the reverse of the pattern.
o Come up with an oven to bake the core
o Make a core
o or the reverse of the core
o buy all the core washes and additives for good peel on the casting.
o Buy a furnace to melt the metal
o Buy a crucible
o Buy fuel
o buy all the tools required to pour a heat.
o buy the aluminum or brass
o and many others I forgot.

The fifth product my machine will produce is molds and cores all in one shot.
It won't buy the furnace, fuel or crucible for you.......but you apply a core wash and bake the mold till it's golden brown like a bun, assemble the mold if needed and make a pour.

All the calculations for shrinkage, draft angles....if the part needed is used in sand casting, proper cooling of the casting can all be dealt with on the computer.

This machine by-passes all the steps of making castings....right up the the point where you pour molten metal into the mold.

Pretty cool stuff.

by DK » Sun Nov 19, 2006 2:53 pm

Nav,

I would wholeheartedly support these purchases and am quite interested in buying some of these custom molds from you.

The custom metal shapes possible alone would make it worthwhile, even if they are one time use.

I say go for it.

by **Navigator7** » Sun Nov 19, 2006 3:32 pm

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by DK
[br]Nav,

I would wholeheartedly support these purchases and am quite interested in buying some of these custom molds from you.

The custom metal shapes possible alone would make it worthwhile, even if they are one time use.

I say go for it.
<hr height="1" noshade id="quote"></blockquote id="quote">

Thanks DK.
My primary interest ($ to repay the loan) in all this hooplah is to create architectural models to overcome permitting objections. 3D printing enhances my other businesses. My customers would use models to gain community support for building projects. Also.....returning to my roots, my former life in subsea, I will create models for the subsea biz which love this form of communication:
<img src="http://i76.photobucket.com/albums/j18/Navigator7/Thefuture.jpg">
Those two white things? Capras. My babies.

Using 3D printing for my spudding interest is simply for the pure fun of it and advancing the spudding hobby. I have a few ideas for long term big buck projects I just can't pursue right now. I really believe there are gaping possibilities for air cannons not even on the verge of being marketed. I hope to change this.

Those of you with 3D capability......means..... I would need.stl files that "hold water".
For spud related printing only, I would seek a fee that exceeds my cost of printing by 15% plus shipping provided there is no conflict with other printing..

Anybody that has a 3D program has probably already figured out the program is useless unless you can do something with the file.
3D stl sent to me via CD or over the net are great.
Therefore a file that leaks and will not print is a huge PIA.
I'm not interested in fixing files. $60/Hr.

The build chamber is 10 x 14 x 8. You can nest, duplicate and play with shapes until the build space is full or maximized. If parts touch, they will fuse.
There is no wasted space or expensive medium used for support as the part is suspended in unused medium. Parts can be built by combining multiple patterns or gluing RP parts together. The resultant structure is then stronger at the joint.
It's magic!

;-)

by **Pimpmann22** » Sun Nov 19, 2006 10:14 pm

As you previously stated, youd allow users to submit .stl files to you for 3D printing, with a profit margin of 15% over cost. Sounds like a really good rate, although how much is 'cost'? Is there a possiblity that you could upload a single, or multiple .stl files of sample objects in which one could suggest the 'cost' of each component. I mean even a ball park figure would suffice.

Who wouldnt be intrested? With a stock lathe you start to realize your limits. Ive actually considered constructing a 3-axis CNC dremel or router. [4 axis look really cool, but adding that 4th axis gets a bit expensive.] Due to my fascination with such, Ive done a lot of research and reading up on CNC machinces. Besides steppers [found for 8$ stocked], and electronics ive found a method in which I should be able to construct a ~24" x 36" x 12" for under 40$.

Anyways, if you could, Id be intrested in some mock prices.

by **Navigator7** » Sun Nov 19, 2006 11:08 pm

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Pimpmann22
[br]As you previously stated, youd allow users to submit .stl files to you for 3D printing, with a profit margin of 15% over cost. .......Anyways, if you could, Id be intrested in some mock prices.
<hr height="1" noshade id="quote"></blockquote id="quote">

I do have to purchase the equipment first.
It's is unfair to members and to me to call out prices for nebulous scenario.
A fair price is...and always will be what a willing market will pay for goods or a service.

What hope to offer will appeal to those who have a vision of something truly different and simply are looking for a way to get there.

I know....because I am one of those guys.

My initial post is about a plaster projectile I'll be calling Scream'in Pete.

It'll scream flying thru the air.
It will be aerodynamic, in that it will not tumble so it'll fly faster and further than most any other projectiles.
It will have a killer "Look" to it. Very appealing.
It will also have a very appealing impact reaction few tire of.

You ask about cost.
I've done sand casting, I've made copes and boy is it a drag...pun intended.

I'm being obtuse as possible.....but I think my service will shread other means of creating plaster projectiles.

HTH
;-)

SpudTech Archive

Scream'in Pete Plaster Projectile