Sprues

AHA !

Someone who feels like I used to . Now about those sprues . You have to fill the molds cavities somehow .The hot product has to get in that little spot to make that part . Sprue use does Not end with you removing parts .I have stretched them and used them for rigging ( ships ) radio gear ( armor ) and teensy scoops and other stuff on cars and planes . Then I take a half full bottle of plastic glue and start filling it with tiny sprue pieces till it,s about two thirds full . Shake well and wait a week . Best filler in the business .And by using that as filler ,it is Not a foreign substance on the surface . You can then cut panel lines or deck plank lines correctly because you are going over the same plastic the kit is made from .

Remember what I said earlier ? You have to get the liquefied plastic in the mold . They could make the sprue to part joint smaller . Then of course you would have to increase the feed pressure and heat ranges too ! Aggravating ,Yes . Necessary Yes . Technology is catching up though . A friend made some cluster gears for a LEGO Technic set with 3-d printing . Nothing short of awesome ! But think, all your small parts of which you speak would then be jumbled in a bag to ship .Would you get good pieces or a jumble of broken parts ? See , there is a downside to 3-d printing too .

Heh - I reuse my sprues and use them as paint stirrers.

I agree in principle, but having gotten a few kits off of ebay where a majority of the little parts were lose....wowser. Think of it as modern day whittling....go down to the general store, sit on the poach and sand.

I use the sprues for additional detail on scratch builds.  right now, i am detailing the new space 1999 eagle.  the sprues are just right for additional rungs on the ladder assy,  and some of the part sprues are being used to soften the lines on the model

I use the small over runs as fill for voids in open areas on some models, like the undersides of tool boxes on armor models. I mix the sections with double bubble epoxy and fill the deep openings with it.

On smaller scale models, 1/144 scale aircraft mostly, you can use sprue cut into sections for weight in the nose of the model to keep it from being a tail sitter.

Or as a hull spreader for tank or ship hulls that need that extra nudge to fit the weather deck or upper hull.

Don't do much resin kits I guess, Duke?

Nope, no resin kits, yet. And I understand that the plastic in those sprues is useful, but consider how much it really costs in man-hours to have that plastic. That's a lot of snipping, and sanding, and scraping for that stuff. Seems to me, you could pack all the little parts of a kit in a small box with some cotton and they would do just fine.

I used to shave sprues down, stuff the shavings in a bottle and add Testor's liquid cement to make filler putty. Works great when you're out of Squadron green or white. Can't begin to count the number of antennas, wires, braces, other parts that I've made from sprue.

From a production standpoint it's cheaper for the manufacturer to use parts trees (sprues) and keep component parts together. Makes packaging and shipping much easier, not to mention quality control. For them to cast individual parts would require a massive amount of retooling and new molds. Add in extra hand processing and their production costs skyrocket. End result? That $20 model kit now costs $100.

Even the newest, bestest and most wonderfullest kit would still have sprues if they were injection molded.

Each individual part that you talk about getting separately from the others would still have to have injection points in order to get the plastic into the mold. So, you would still have sprue gates at the part, and sprues attached to the part. And if the parts had the shortest possible "sprue gate stubs" sticking out of them at the time of packaging, those would break off randomly from the parts, creating a jumble of gates in the box bottom, and tearing off the part without any control,,,,,,,maybe damaging the part.

Having parts on the sprue helps with identifying any parts that are "very close but not exactly the same", with numbers on the sprue next to the part. Having parts on modern design sprues protects the parts during shipping and handling, also. A well designed kit has the parts lain out so that they sprues nest correctly in the box to give space where it is required for tall parts, and to keep outer surfaces from rubbing scratches into themselves on the other parts in the box. Open a quality kit slowly and with an eye towards noticing this once, and you will see the empty places in sprue B to make room for a tall part in sprue A, etc.

Rex

Tankerbuilder

Gonna give your bottled brew a try. That sounds like a super idea. I agree it's annoying to remove and clean the parts but that is part of the hobby. I use my left over sprues in many ways:

I stretch it to fill gaps, to make lines for engines and wheel well detailing, plugging holes in plastic, make holders for painting wheels, and much more.

I agree that until people are using 3D printers, we are stuck with sprues, and I'm glad folks find a use for them. But you'll notice that someone is asking about 3D printing Star Wars figures on another thread here at FSM, right now. It's just a matter of time until 3D printers break into this hobby, and that will be the end of retooling, molds, and injection molding. Labeling will still be a problem, I get it. Maybe they'll continue to make the smaller parts on sprues, but my guess is it's just a matter of time before some enterprising person finds a way to break into the model making business with a little innovation.

Hi :

 You can be sure someone will figure it out .This is something you have to remember though .Watch an eighteen wheeler going down the highway  .Maybe your favorite kits are in there  .Now watch that puppy go over a pavement to bridge seam or just over rough panels of pavement if it isn't blacktop .See how that trailer bounces up and down ?Remember your favorite kit is in there , probably with thirty or forty more cases of the same thing .

    Now imagine those little parts NOT on a sprue . How much shaking can they take before being unuseable ? Putting them in a box with cotton is a good idea , but , do you want to really pay the extra packaging costs involved ? I think the mfgr's have done a good job in some cases in paring down the size of the sprue gates , but they'll always have to be there until 3 - D printing becomes so cheap it will surplant injection molding .

    On that I believe I'll be gone for about thirty years or so . You see , they won't pare the price down until the price of a 3 - D printer in that size and scope is a reality and that means some years down the line yet , I do believe .

I'm not sure that the current selection of 3D printers are capable of the level of detail scale modeling needs. The resolution (layers) just isn't fine enough - yet. If it were you can rest assured that I'd be doing my best to get one. I need a large number of N-scale C&O coal hoppers, 200+, and at $15-$20 each for retail ones...

That rich I ain't!

3D printers are already being used in modeling.

Folks are drawing the part in CAD 3D, then printing the part out, giving the part a clean up, then pulling a mold from that master and selling the parts.

The new McDonnell wing tanks for 1/48 Phantoms was done that way just a few weeks ago,,,,,,and I believe the Battleship Roma was done that way, back before the VA Beach Nats in 2008,,,,masters of some parts were on display there near the amber V-8 engine block.

even 3D printers won't get you away from sprues or casting blocks though, the part still comes out attached to a block, and if you use the part for a master, you end up with a possible seam and a definite mold block to remove and sand.

The guy asking about taking an existing model or figure and "printing one out" doesn't get that you don't just scan in the part and push "gimmee" and get a copy of your thing back out in the same or a different size. "All" you would need to do that would be a box that you set the figure in, and when you hit "gimmee", it would scan all the 3D data in, send it to your processor, and then send that data into your 3D printer.

In the meantime, there has always been a way for people that want 1/48 or 1/72 scale models to get one without putting it together. As of today, there are 3 methods that I know of.

Sprues are a neccesary evil for injection molded kits, the plastic has to get into the mold somewhere!

But you could try a Hobbyboss easykit, they do most of the clean up for you, no sprues on the mayor parts.