Hi,
I'm starting to think in going into the injection mold making business. Any comments on that matter? Is it a good business, a hard one, difficult one? where to start? Take into account that I'm starting from 0 :rolleyes: so any type of comments are really appreciated. Really what I need is a thread...that its title should say "How to start a small mold making business and not die in the effort" :)

The mold and die machining discipline is the most difficult of all tool making processes. Plastic injection molds are the most precise and highest quality molds. The only molds that are more precise or have a higher degree of finishing skill would be for optics...

Ask people to list the machines needed, and the supporting tools and technologies for being successful at it...

It is a good buisness only, if you're good at it.
Reputations follow performance and a reputaion can be affected by very little gone wrong.

This discipline is definetly NOT for the inexperienced...

If you've got a million dollars, you'll probably be able to set up a small mold shop. Add a couple employees with 15 to 20 years each of moldmaking experience, and a mold designer with a like background, and you'll be ready to watch the work go to China at warp speed. Seems it was Ross Perot who described this phenomenon as "The giant sucking sound".

I used to be a material handler for Keytronics in Spokane Wa. They make keyboards for computers like the micrsoft natural and the ibm thinkpad. I was the guy that mixed and dried the plastics and put them in the machines. Well most of the machines went to mexico. Thats the way of the world. Why pay me at that time $7/hour when you can pay someone else $0.20 and get a tax break on shipping from our government.
Enough on that. Anyway If you could do one off stuff small production runs then you could make it here in the US. The machines are not cheap and the molds are very spendy. If you have good machinist skills you can learn to make the molds. There is alot to it more than just cuting out a shape.
Wish I could be more help but alas thats about the exent of my knowledge on the subject.

Donny

I came into contact last year with moldmaking, as Scott Bob says it is the most difficult discipline of toolmaking. On press tools there's a margin to "default" on tolerances, but on molds you must keep in mind the shrinkage of the moulded material, the flow of the material, where to split the mould, hot & cold spots in the mold & the runners as well. Sometimes there's a need for a "hotbox" when the runners are long.....
Well i have mentioned just a few things, but all in all i find molds much more challenging than the run of the mill type press tools, the only press tool that makes my toes curl of joy is progrssive press tools, but these type of jobs does not come my way often!

Klox

The mold and die machining discipline is the most difficult of all tool making processes. Plastic injection molds are the most precise and highest quality molds. The only molds that are more precise or have a higher degree of finishing skill would be for optics...

Ask people to list the machines needed, and the supporting tools and technologies for being successful at it...

It is a good buisness only, if you're good at it.
Reputations follow performance and a reputaion can be affected by very little gone wrong.

This discipline is definetly NOT for the inexperienced...

I know that mold making is one of the most difficult of all tool making processes. Maybe in the states this is the case, but here in Mexico yo can find really bad quality plastic products, like buckets, cups, etc... that's the kind of molds I'm aiming to...not high precision molds like the ones used for celular phones, or high quality appliances, Got the idea? I want to make my own molds for this kind of cheap plastics prodcuts and not pay 100K for a nasty bucket mold :p .I know that to get to high precision mold making you need millions of dlls for getting cnc machines, mold software for the design, and really experienced people. My idea is to be realistic and start from the bottom, I'm not in a hurry and I am pacient and my goal is cheap not precision molds, well that's for the start, maybe in 20 years I will be making aircraft parts or something like that :banana:
Regards...
Hector

I came into contact last year with moldmaking, as Scott Bob says it is the most difficult discipline of toolmaking. On press tools there's a margin to "default" on tolerances, but on molds you must keep in mind the shrinkage of the moulded material, the flow of the material, where to split the mould, hot & cold spots in the mold & the runners as well. Sometimes there's a need for a "hotbox" when the runners are long.....
Well i have mentioned just a few things, but all in all i find molds much more challenging than the run of the mill type press tools, the only press tool that makes my toes curl of joy is progrssive press tools, but these type of jobs does not come my way often!

Klox

Hi...
I like difficult things... :cool: and I also like reading :p I just got about 10 different books about that difficult things you mention about mold design, I'm aware of that, and I know I'll have to learn lots of things and log time passes before I acomplish the simplest well done job...but that's the fun part of the learning process :cheers:
Keep the comments coming...know that I made clear my intentions, remember... :p I'm not aming on the super high precision molds!
Regards...
Hector

Hector- I was going to ask what sort of mold making you were interested in - but now you have clarified that.
About 5 or 6 months ago there was a thread here that discussed (or started to) low pressure injection molding. It was a process that used recyclable plastic like soda (Coke) bottles and such.
I think the Gingrich/Gingray/or something like that (spelling - sorry) fellow has a set of plans and one of the Zone members was maybe going to give it a go. Sort of surprised that member hasn't popped in - maybe dropped out. I suspose you have done a search on the CNCZone might look for the other fellow on the web too. He has a whole heap of various plans for simple approaches to similar backyard manufacturing.
Looking forward to hearing your progress!
Cheers - Jim
Here - try this site - might get you close (its GingEry)
http://www.lindsaybks.com/dgjp/djgbk/inject/index.html

I'm a tool and diemaker by trade; but I worked for 7 yrs in the local mold town(about 30mins down the road)
I have made trim dies; press dies; draw dies; I made the prototype mold and production molds for the Prowler Ins panel/dash re-enforcement beam (Mag/diecast; full width of the car) I made from the Ford drawings (which I had at home on my CAD) the Prototype and production/trim dies for the beverage holder in the 92'ish Mustang (pulled up out of the center console)
I re-built many times the T Truck center diff gearbox (Ford again) made a few other interesting molds when I lived in Calgary Alberta; winter bases (the phones to listen to underground reflections from the Oil industry crews)
Made a Motorcycle brake/cluch lever (that folded up when you fell going uphill/dirt bike) called the Champ lever; not sure if it's still around; and many many others
I think you need to think about joining a shop to learn the ropes; then work up to thinking about starting a shop in maybe 15yrs
I loved the 4 color Mustang tail light mold; the reflex (stuff that refects the light back) is soooo cool; but at $1,000/sq in you dont screw any of it up

Ok, highend molds aside what about a simple pour mold like for rubber or silicone or a layup mold fiberglass or carbon fiber. Machine time isn't an issue at this point, I'm just comparing thoughts or ideas on different types of molds.

Hector- I was going to ask what sort of mold making you were interested in - but now you have clarified that.
About 5 or 6 months ago there was a thread here that discussed (or started to) low pressure injection molding. It was a process that used recyclable plastic like soda (Coke) bottles and such.
I think the Gingrich/Gingray/or something like that (spelling - sorry) fellow has a set of plans and one of the Zone members was maybe going to give it a go. Sort of surprised that member hasn't popped in - maybe dropped out. I suspose you have done a search on the CNCZone might look for the other fellow on the web too. He has a whole heap of various plans for simple approaches to similar backyard manufacturing.
Looking forward to hearing your progress!
Cheers - Jim
Here - try this site - might get you close (its GingEry)
http://www.lindsaybks.com/dgjp/djgbk/inject/index.html

Not quite a backyard manufacturing :rolleyes: I'm planning to nail a used VAN DORN 150 ton Injection Molding Machine :p but the parts I intend to start with are not precision molding, just plain cheap plastics gadjets...like bukets or small trash baskets or so...

I'm a tool and diemaker by trade; but I worked for 7 yrs in the local mold town(about 30mins down the road)
I have made trim dies; press dies; draw dies; I made the prototype mold and production molds for the Prowler Ins panel/dash re-enforcement beam (Mag/diecast; full width of the car) I made from the Ford drawings (which I had at home on my CAD) the Prototype and production/trim dies for the beverage holder in the 92'ish Mustang (pulled up out of the center console)
I re-built many times the T Truck center diff gearbox (Ford again) made a few other interesting molds when I lived in Calgary Alberta; winter bases (the phones to listen to underground reflections from the Oil industry crews)
Made a Motorcycle brake/cluch lever (that folded up when you fell going uphill/dirt bike) called the Champ lever; not sure if it's still around; and many many others
I think you need to think about joining a shop to learn the ropes; then work up to thinking about starting a shop in maybe 15yrs
I loved the 4 color Mustang tail light mold; the reflex (stuff that refects the light back) is soooo cool; but at $1,000/sq in you dont screw any of it up

How much$? for a 1 or 2 months mold making camp training, I love Canada, and will work for free :)

I love looking at mold pics

Gravity molds are also fun to make!

Klox

Hector,

Do you already have a shop with machinery or are you still going to set up business?

The type of machinery you need will depend mainly on what type of end product you want to produce, finish and tolerance required and also on the size of the product.
We work maily for the auomotive industry producing moulds which we then inject ourselve.
Let me know if you have any questions

Hector,

Do you already have a shop with machinery or are you still going to set up business?

The type of machinery you need will depend mainly on what type of end product you want to produce, finish and tolerance required and also on the size of the product.
We work maily for the auomotive industry producing moulds which we then inject ourselve.
Let me know if you have any questions

Hi.
I'm setting up the business...looking for used equipment mainly...an the objective is to produce cheap plastic household items..nothing new around :) just plain plastic cups, spoons, napkin holders, maybe the bigest thing cold be a water bucket. Have some questions for you?
1. What tolerances should I look forward to obtain in teh molds
2. What kind of cnc machine center whould you look for? or what will be the machines needed to start machining this kind of mold. What type of machines besides the machining center do you need for finishing (polishing) the molds, etc.
3. As you mention earlier, you inject your self. What size and brad of injection molding machinesd you use. Any recomendation on a brand or used molding machine seller?
Regards...
Hector

After reading alot of the posts one question you might want to ask yourself is do you want to be a moldmaker or a moulder? You could go either way and I would suggest if you are starting from scracth to try to pick one or the other and try to concentrate on it to be profitable. Then afterwards if you want to shoot for the other than you can see what possibilities you have to invest in. The plastics business is a cutthroat business with automation( being able to run 24/7) the way to get the lower prices to get the business. This all involves the use of robotic pickers teamed up with regrinders attatched to the machines to keep them going. But also being in Mexico, you also have the advantage of the cheaper labor going for you.

After reading alot of the posts one question you might want to ask yourself is do you want to be a moldmaker or a moulder? You could go either way and I would suggest if you are starting from scracth to try to pick one or the other and try to concentrate on it to be profitable. Then afterwards if you want to shoot for the other than you can see what possibilities you have to invest in. The plastics business is a cutthroat business with automation( being able to run 24/7) the way to get the lower prices to get the business. This all involves the use of robotic pickers teamed up with regrinders attatched to the machines to keep them going. But also being in Mexico, you also have the advantage of the cheaper labor going for you.

Well I'm not gaining for high precision parts or very low tolerances I don't even think I can acomplish that in 10 years. I'm gaining for cheap plastic products. I know that wanting to become a molder and mold maker at the same time sounds maybe imposible (chair) but I have some advantajes and disadvantages being in Mexico. On the good side this kind of cheap products really sell here in Mexico and I have plenty of cheap labor. By the other side the bad one...Is that for standing up a business here is very hard, cheap labor but lots of problems with taxes, bad goverments, poor incentives etc...The only way I see of acomplishing this idea is to make the molds myself...I can not see the possible way of paying a molder to build a mold 20-30K for each mold...I need to have lots of cheap products..that means lots of molds...eventually having the power to make my own molds I'm sure that the cnc machining equipment will pay for itself with other jobs besides the molds...If I can put a person exclusively to building one mold each 1 or two months (remember small, not highly precise molds) that will be a hell of acomplishment. As I mention earlier I need lots of products I can sell, I will be nuts If I invest that kind of money for just a product for sale.
Regards...
Hector

Consider doing an apprenticeship in toolmaking which has in-house moulding facilities.

The skills and experience you will gain, will guide you later if your endeavours are to do this yourself.

Take a look at www.plastics.com, lots of experience is to be found within the forums.

All the best.

BT1

Consider doing an apprenticeship in toolmaking which has in-house moulding facilities.

The skills and experience you will gain, will guide you later if your endeavours are to do this yourself.

Take a look at www.plastics.com, lots of experience is to be found within the forums.

All the best.

BT1

Hi,
The problem is that I haven't found someone that will offer a apprenticeship here in Mexico. I will kill :boxing:, just kidding for that kind of opportunity.
Regards...
Hector

Why not start out molding, subcontracting the (expensive) molds and then tool up for doing molds yourself.....
I have learnt a few things about molding by just making molds for molders! I must say at this stage i'm not interested in molding itself maybe later on.

Klox

Consider doing an apprenticeship in toolmaking which has in-house moulding facilities. This what most Moldmakers go thru. at least 4 years worth. I started in the industry as a wax tool maker and then went on to do Plastic ,Die Cast.

I do say it is fun, but hard these days to find a job doing it. Do to it all leaving the states.
I know allot of it has come your way, so this is good for you.

Look at making some simple poor molds to start.
If you are used to making parts , you need to change the mind set of reverse image of what you are making.

Hector I am neither a mold maker or an injection molder but I have been around them quite a bit in the past few yrs trying to get some molds made for some products I wanted to produce. I also have run my own business and know the pitfalls that await you if you start off wrong. The very first thing you need to do is do a business plan. If you don't know how to do one there is help available for that. It might be harder to find in Mexico but it is available.

Now for my personal advice. Look for used molds at auctions or contact mold companies to find if they have any unused molds. I happen to know where there is a brand new mold for one of my products that has never been used due to disagreement between me and the mold maker. In his shop I know that there or three or four molds sitting that are not making anything. You can make new inserts for much less than new molds. It's a though anyway.

Mike

A definite tough business to start out in. Trouble too if your looking at making molds, regarding household. There are many, many people all ready doing this (as with everything!) so if you are going to compete with what is all ready established. You really want to make sure your products are either better or cheaper, even both.

I did my apprenticeship at a company that made there own range of houshold products, as with contract tooling. We made and molded all kinds of things from buckets, bins, trays, kettles etc and the list goes on.

Experience is a big bonus...

Cheers, BT1.

You can make new inserts for much less than new molds. It's a though anyway.

Tell me more about this inserts?

Regards...
Hector

Hey,
I worked in a mold shop for a few years. An insert is the part that you spend hours machining, the area of the mold that forms the plastic. Basically you rough out large pockets in the mold A and B plates. Usually with a step and a way to bolt the insert in from behind. Then you make the 'mold' on other pieces of material (the inserts). The benefits are; if you scrap it, you only scrap an insert, not the whole mold plate. If the customer needs a big change, you just remake the insert. I've even seen where several different sized parts where made with the same mold base, but with different inserts.

The insert has to be a very close/flush fit to the mold plate. Any slop or uneveness can cause flashing and other problems. As one of the other posters said, if you can find an older mold base, you can machine out the old mold pattern and make pockets for your new inserts. Good luck.

From an owner and operator of a mold making shop. We slowly moved away from the injection molding business to a job shop because, like stated earlier, everything is moving overseas. To be a mold maker, you need to become a machinist, CNC programmer, designer, EDM operator, CAD/CAM designer, and a few others to be able to compete with this kind of market. I personally know a few people who can do the above tasks, but are not qualified to be a mold maker. It takes more then a few years of experience to start cutting your first mold.
To answer some of your questions: First of all there is no such thing as an injection mold with loose tolerances. Your part might be, but not the mold. You also need different molding machines for diff. Parts. You cannot mold a bucket with a 150-ton machine unless it is a very small bucket, so before making any purchases, do a little research. The easiest part of molding/mold making is buying molding machines. At local auctions they go for dirt-cheap prices. There is much much more involved to this then you can imagine. To get started enroll in a school. Start working in a shop so you can get your feet wet. After a few years, decide if this is what you want to do, and then go from there.

hector

there is lots and lots of information available from the web. goto molding machine company sites, and look at the white papers. you will learn about all sorts of mold making terminology, and how complex even a simple mold for a garbage can could be.

imagine how the the walls of a typical plastic wastebasket are.. maybe.. .075 .1? anyways. that means your tolerances do have to be pretty low?

regardless - there is tons of info if you look for it. asking people for basic "how do i start a mold shop" is just asking for generalized advice that wont help much.

the gingery book might be a good 15$ buy for you. not that the machine is usefull, but it describes manual machining of an aluminum mold.

check out www.protomold.com to see what the competition is. its very tough. this company spent many millions on automation and 5 axis cnc centers. they only need a few people to run 15 machines or something...

plastic manufacturer websites will provide lots of info also, possibly. also, consider all the other support material you need for a machine, like a plastic pellet hopper, exhaust fan and system, and likely plumbing, and 440v or more electricity? all of these costs can add alot to a $15,000 used molder.. i would imagine.

as far as a fair estimate for how much it would cost to buy equipment to make some first molds for a decent used commercial machine.. lets guess:

used\referb 5 axis CNC Center - auction price - $20-40k ? maybe? i dunno.
Lots of tooling and stuff like that.. specific stuff for the first job - $5k?
surface grinder? a cheap import? - $2500
polishing and finishing equipment - $1200?
big blocks of steel or aluminum... for a guesstamite: checkout www.metalexpress.net

making molds with moving inserts, proper cooling cycles, proper cooling chanels, and other issues is generally not a task for someone who has to ask in a public forum what basic issues with the plastic mold making industry.

i would imagine you could build a reasonable business plan around aquiring used equipment carefully on auction market, and then using cheap labor to make inexpensive comodity items like trash bins.. then get a loan to buy the equipment? maybe. loooking at books on finding startups will possibly really depress you when you realize you are going to be a businessman, not an engineer or whatever...

with luck, "if you build it, they will come"
get a working cnc center and molding machine.. i bet someone will help you learn to run it for a reasonable rate.
hell. fly me out. i will figure it out.. and show you. im sure there is a faster, intuitive, well researched and executed and inexpensive path to your goals.. the research could take time. its a classic engineering maxim: "you can have 2 of the 3: speed, quality, low cost"

hope this helps.

ok. more on that cost thing.. i realized..

you need 3d/cad software with a mold wizard, a year of experience, and a NC toolpath generation progra, or a damn good NC programmer.

buy a real fast computer with a good 3d card! $4500 and also, you probbly need a bunch more stuff than i mentioned. 5k of tooling should do it.. maybe a 10-15k used 4axis cnc lathe, and another computer.
and some desks, lamps, shelves. a few reference books. well. alot of reference books. a small LAN, internet access, health insurance for the workors.. oh wait. thats mexico. duh. uhm. fish tank, a secretary... hmm what am i forgetting.

you need 200k probably

I am a Moldmaker and have had my own moldmaking shop for 7 years now. I have done everything from large vacuum cleaner parts to very tiny computer parts. I have done hardened steel multi-cavity production molds, and single cavity prototype molds. Moldmaking is a very precise process, but once you learn the way it is done, it gets to be routine. I use a surface grinder for a lot of the work, along with Sink EDM and Wire EDM. Most of the milling and drilling I do on a Machining Center.
As for the "cheap parts" like the buckets and cups, just because the parts are simple, it doesn't really mean that the mold can be built cheap or that it will be easier to build. There will always be a certain amount of "precision" required to put a mold together and not have a lot of flash to trim, or uneven wall thicknesses, or weak point in the part. Also, if you plan on building molds, get used to spending hours and hours with a stone polishing, plastic will show every single scratch in a piece of steel or aluminum, and even cheap parts won't sell if they look scratched or "used". In most cases though you can "texture" the cavity to hide a good bit of the machining marks, you can use a bead blasting cabinet to texture. If you just want a few cheap parts to mold, maybe check with some mold shops around, most shops are always looking for more work, and these days the ones who are still in business are usually trying to find ways to build them cheaper and faster.
This is my first post here, I have been around CNC for 12 years and this place is awesome. Im very glad I found you guys.

hi Jim

we have a Maverick Mold & Tool right in a town 1/2 hour from me (Ontario Canada)
Are they part of your operation?

Welcome to the forums; these are a great bunch of guys here; helped me out a ton
I have been at the trade for 35 yrs; and yes molds do take lots of time (I used to do Lex; and polish is everything)

No, my "operation" consists of me and my machines, and occasionally my better half doing the taxes. I purposely kept my shop small to reduce overhead, because I know that the molding industry in KY is flooded with moldmakers, and ther just hasn't been enough business for me to grow my shop. I am branching out into other areas of machining to help take up the slack from the loss of moldmaking business.

I have always been very interested in hobby cnc and home brew cnc. Before I got my machining center I was researching a lot of different retrofits for my manual mill. There is so much information out there that it gets confusing just keeping straight what you could do. I even came up with a design for a High-speed CNC mill dedicated to making 3D electrodes. I haven't put my ideas to work as of yet, but I keep it in the back of my mind.
I am currently looking to retrofit my Sink EDM machine to be CNC controlled. The way I work, I try to keep both my Sink EDM and Machining Center running, and then I go and do work on my surface grinder. I get a lot of work done when I don't have to baby sit a machine.
Jim

Like me; i just run my little shop and i do everything

I am slowly getting bigger and making more complex parts; like these babies
http://www.modelbarrels.com/files/7-92mmMG17-24th.jpg
CNC turned then CNC drilled
German 7.92mm MG17 for the 1/24th scale ME109G
my site (http://www.modelbarrels.com/)