40 replies to this topic

[Oroku Saki]

It's great to be able to help with ideas.

Right now, I'm broke, so I don't have any money to put together a larger scale project like this. I wonder if anyone else has any ideas on material components. Another idea that I was thinking for the casings was to make it out of full metal. It would be interesting to see someone come out with something like that.

According to my research, I believe that the Studio Creations design is the simplest and cheapest vacuum form table to make. I haven't bought the Lindsay book on vacuum forming, but that may also have some great ideas in there.

[xedice]

You don't need an expensive vacuum molder to make plastic parts. At hobby shops they sell this stuff called "Plastic Resin". You mix it up, pour it into a mold, wait a few minutes, take it out, and viola, you have your plastic part. I was actually thinking about using this to make a new trigger for my SM1500, my current one is broken. The downside is, it costs about $25 for the mix, and you got to make your mold yourself also.

[rusty]

Great ideas but the plastic resin seems like the best thing to try right now. That way if it works i wouldn't have wasted the money on a vaccum forming table. Also vaccum forming seems to be more for the outsides of things.

[sporkboyofjustice]

You can make a small vacuform table for about $20 (I did). But the pieces you can make on it will be brittle and thin. Resin casting is a much better idea and you can do it on the cheap too. I'm thinking about doing an article about casting small bits in epoxy (it's resin), would you guys be interested?

[rusty]

I'd most definetly be interested

[rusty]

They did originally make those. I think they were called metal molders, and it was basically just a toaster over with a pan for the lead pellets to be melted in and a place to put the molds. Unfortunatly they got there asses sued off because of dumbass parents who left their six years alone with one of them.

[xedice]

Plastic resin doesn't require any heat / oven at all, just room temperature and some time. It's fairly cheap, the tricky part is making the mold.

Go here for more info:
http://nyny.essortme...rpolyu_rypr.htm

No need for ovens, do it yourself kits, just a few things:

1.) Make mold out of mold compound and legos, wood, whatever, just so the liquid can take the shape of your mold container
2.) Swab mold with release agent so plastic part can be released from mold
3.) Mix up resin, pour in mold
4.) Wait for it to dry
5.) Get plastic part out and use.

I've never made a nerf part out of resin, don't know how it reacts to stress of being used and abused, but I have made my own lego pieces out of it, and it is pretty cool and easy.

Edited by xedice, 26 March 2004 - 03:00 PM.

[sporkboyofjustice]

They also used to have toy vacuform machines as well. The only metal forming toys I have seen had to do with lead casting.

[Oroku Saki]

That resin stuff sounds cool. Great idea to use them for Lego pieces! I wonder how you can mold, say larger Nerf parts with it.

You can make a small vacuform table for about $20 (I did). But the pieces you can make on it will be brittle and thin.

I think the durability of vacuumformed plastic may vary depending on the thickness of the plastic and how the table and mold are used.

[Katachi]

Actually, I acquired a book on making a small, tabletop homemade injection molding machine. Lindsay Publications prints it, and you can buy it directly from them. They also have some other cool books.

The injection machine book is here: http://www.lindsaybk...ject/index.html

With my job and stuff, I haven't gotten around to building the injection machine, but I think it may prove useful in making smaller parts.

For the larger parts, it may be more of a challenge. One idea that I can think of is to vacuum form plastic to a plaster mold. Vaccum forming is used by movie prop makers. (one of the most well-known uses is for Stormtrooper Armor) Basically, a vacuum form unit is a table with a hole in the middle. Under the table, a vacuum hose is hooked up, and the mold is placed over the hole. When molding, the softened plastic is sucked onto the mold by the vacuum.

Edit: I just found out that Lindsay also prints a book on vacuum forming, which is at this link: http://www.lindsaybk...vacf/index.html

Looking at the pictures of this Vacuum Forming machine, I think that some of the other prop making places on the internet have ideas for making a simpler and cheaper vacuum forming table.

One of my favorite prop sites has a good section on vacuum forming, which is here: http://www.studiocre...able/index.html

Another idea that I was thinking about would be to somehow make parts from metal or other materials. If only I had easier access to metal machining equipment.



UPDATE: Speaking of patents, if Hasbro had anything patented on their Nerf guns, they would have the patent information listed on the box or the gun itself. Looking at all the Nerf guns that I own, I do not see anything marked for this. The only thing that I see is a copyright date. I even checked on the box for the Nite Finder, and all I see is a copyright date. This probably explains why Lanard has not gotten into trouble for reverse engineering Nerf guns, since they don't slap the Nerf label on their stuff.

Well well well, look what I found in the topic archives!

Oroku_Saki, if that injection molding book is any good, I owe you

Hmmm, you guys are going in the right direction, but here's some info from someone with experience working with plastics:

I would asssume Nerf holds the patents to the internals of the guns. You can't patent the concept of forcing air through a tube, like the spring/plunger guns, but you can patent the mechanics behind HOW it's forced through the tube, such as the shape of the airchamber, plunger, o-rings, trigger, springs, and the mechanics behind the firing process. So if you flat out cast parts from a nerf gun and re made the plunger/plunger lock/trigger mechanisms, yeah it's patent infringement.

Now here's the thing about making illegal copies: I really don't care.

1)The demand is there, and I'm going to be making guns that nerf no longer offers, not guns to directly compete with their guns. For example, making a new handgun to compete with the Tech Target and/or Nite Finder, that's not a good idea. Making a better Crossbow, or improving on a gun that nerf tried once, and didn't get right, like the Chainblazer or something, sounds like a good idea. If I made something like a Chainblazer that worked, didn't jam, was accurate and powerful, and had a 50 shot ammo chain, there's no current gun that Nerf makes to directly compete with it. If they did make one, I would definately stop making mine and try to promote and support theirs. My business is a fan business.

2)Production of our stuff will be so limited, it's not even going to be considered "mass production" If I made the Chainblazer from the previous point, I MIGHT make 25 of them TOTAL. Ever. Nerf isn't really going to care. If they even notice at all.

3)Corporations don't like to waste the time and money taking someone to court. I know. I have friends who make movie prop replicas. The first thing to happen when you make a copy of copyrighted or patened material is the coproration's lawyers issue you a "cease and desist" letter. Sometimes they seize your molds and product, sometimes they don't. Either way, it's just a slap on the wrist and they take your toys away. No lawsuit. No jailtime.

Now for the plastics:

Vacuforming is fun, but not durable enough for nerf guns. Think of having a nerf body made out of a 2 Liter Coke bottle. The plastic sheets used for vacuforming are in the 2-3mm thick range. DEFINATELY not strong enough for nerf gun shells.

2 part resins are durable, but not the kind you pick up at the craft store. Those are WAY too brittle for making shells out of. Would you want a gun that cracks when you drop it on cement?

Don't even suggest fiberglas. Too messy and brittle if you don't do it right.

I've considered directly replicating the mechanics of several guns, but most have so many precise parts, that it's not worth doing. There's only a couple that have a clean mechanical design and can be partially copied and applied to a better gun. Others, like the Tech Target, only have 5 pieces total and can be easily simulated with various lengths of pvc.

We are currently trying to find a better substance for making custom o-rings and gaskets out of. There are some urethanes I want to try out this summer still


Great. Thanks guys. Now you got me thinking about a 50 shot Chainblazer that acutally works.... I think we sold our last one in like Feb or March... anyway, I'll see if it's worth doing. Sure would be nice for a heavy machine gun nest for capture the flag games

Oh and the 10 shot I'm always talking about? Electric Eel guts. Mostly just the parts to advance a clip. It's a very simple design with minimal parts, but it can be improved in about 5 places, with the parts replicated in a high impact industrial grade resin. I'll custom make longer clips (4 freakin darts?! who's idea was that?) and I'd probably make it pump action, instead of a pull back plunger. So it'll brobably be about 30-40% Eel, with major improvements over a working advancing clip design. But hey, hopefully by the time I make mine, nerf will reissue a better Eel. And a new Crossbow.

[xedice]

What kind of stuff do you use Katachi? I have played around with resin from craft stores just a tad. I ended up just cutting several layers of sheet metal in the shape of a trigger, gluing them all together, and sanding it. It works well but way to sharp, cuts grooves in the pump tube of my nerf gun and harsh on the fingers.

Im still wondering if I should buy another batch of resin and try to make another trigger. Where is a good place to buy cheap yet strong resin? I'm not looking for all the extra junk that comes with it like spoons, fancy neon colors, and big flashy bottles.

[Katachi]

What kind of stuff do you use Katachi? I have played around with resin from craft stores just a tad. I ended up just cutting several layers of sheet metal in the shape of a trigger, gluing them all together, and sanding it. It works well but way to sharp, cuts grooves in the pump tube of my nerf gun and harsh on the fingers.

Im still wondering if I should buy another batch of resin and try to make another trigger. Where is a good place to buy cheap yet strong resin? I'm not looking for all the extra junk that comes with it like spoons, fancy neon colors, and big flashy bottles.

www.smooth-on.com . I use Smoothcast 300 for my propwork. Great stuff. I think they have several grades of resin that are more impact resistant, but it's all I need for what I do. 1:1 mix raito, minimal fumes, good set time... I don't know about cheap though. Quality costs money. But you can get a 2 pint sampler pretty cheap.

[Oroku Saki]

It's great to know that I have given you a great idea, Katachi. As I may have mentioned, the injection molding book has a design for making a molding machine for smaller parts, usually up to about an ounce.

Thanks for the further info. It's great to hear from someone with more experience in this field. Some of the ideas that I had for a Chainblazer-like gun involved using full-metal parts to make it more durable and otherwise kickass. Now that I live closer to my parents, who have a garage full of metalworking equipment and tools, I have easier access to making the stuff I want. Let me know how your plastic-working projects turn out.

Edited by Oroku_Saki, 01 July 2004 - 05:42 PM.

[Katachi]

It's great to know that I have given you a great idea, Katachi. As I may have mentioned, the injection molding book has a design for making a molding machine for smaller parts, usually up to about an ounce.

Thanks for the further info. It's great to hear from someone with more experience in this field. Some of the ideas that I had for a Chainblazer-like gun involved using full-metal parts to make it more durable and otherwise kickass. Now that I live closer to my parents, who have a garage full of metalworking equipment and tools, I have easier access to making the stuff I want. Let me know how your plastic-working projects turn out.

only an ounce? shoot. I need something bigger. Ah well I should still check it out. I can already do 2-3 ounce two part mold injection molding, but the resin runs out the seams, and there's air bubbles... If I could make at least an 8 ounce machine for one part molds with a birthing slit, I could do some crazy stuff... I know how to do one part molds with silicone and urethane, but I haven't tried them yet. most nerf parts could be made in a one piece flat mold, since you only need the shape of stuff, like the trigger. You dont' need to make molds of both sides.

[Oroku Saki]

The only larger injection molders available that I know of are industrial-grade equipment, which can run anywhere from $20,000 to a few hundred thousand bucks. With the design in the book, you may be able to make a larger machine for making larger parts, but I am not sure how this can be done.