Thanks Bruno. I have more coming. I have been making molds, but unfortunately have not been able to show them.

All of the molds I've made, and there are quite a few, fit into a single drawer. They're small.

@@JohnSL you manufacture to order?

Glad you like them!

Thanks again!

I love that podcast. And thanks for coming over.

I didn't know you had an interest in that too! I'm happy to collaborate on a project if you're interested, as your machines are all larger than my largest machine.

@@JohnSL Hi John, yes a collaboration sounds fun. I'm thinking about using a HO train as a parts conveyor between work cells. Maybe we can come up with a hopper car that I can move molded parts on a track. 50 cars should be a good start. we can sell them too

Thanks!

I've been thinking about doing a video on SLA inserts for injection molding, but haven't gotten around to it. If you have SLA printer and have something in mind, shoot me an email and we can collaborate.

@@JohnSL yeah, ive got a printer and have even Made some 'pallets' Out of Aluminium to hold a smaller SLA Insert. The only Problem i found is that cooling is an issue. Once i Figure It Out and get Something Worth watching i send you an e-mail. Greetings

Thanks. I'm using removable Loctite these days to keep my pins in place. I've also switch to 1/4" pins, with a smaller hole drilled all the way through the back. That way if I need to, I can remove the pins and then do any required machining. So far I haven't needed to do that, but it takes very little extra time.

It sounds like that's a good fit for desktop machines. LNS and other companies sell small batches of plastic. So getting started feels intimidating, but it's actually not that bad as long as you're using simple desktop machines.

There are many different factors that contribute the pressure, temperature, clamping force, etc. What I should do is keep track of the parameters I've used for each mold. I don't. I dial it in again each time, which means I "account for" all of those factors by trial and error.

@@JohnSL a description of every sort of process type of job that requires a human to adjust by experience 👍

I often add vents, but have found they're not always needed. I've been told that the surface roughness of the milled halves provides some venting.

@@JohnSL Slower injection fill rates will control burning and shorting problems. And since that's not possible with a plunger machine. Parting line vents are advised. Place them where at last section is filled. Rough surfaces foul quick and require constant cleaning. Venting gases can arc and damage cavity walls.

Hope this answers all your questions: kzfaq.info/get/bejne/qap-ral8ptGbaZs.html

Details are in the video description as well. Here's a link: www.abplasticinjectors.com/ab-150

@@JohnSL Out of curiosity, what price did you pay?

Yes the pressure would be too low

It's not for several reasons. One is the temperature of the mold. Another is the amount of plastic in the cylinder. As it increases in temperature, you need less pressure. But yes, keeping records would be a good idea for molds that I planned to run again. These molds have now been retired and I actually used a different machine previously to run these molds. So the settings would have been slightly different.

For future reference. It's always good practice to record and retain all cycle parameters that produce acceptable parts.

I don't. A mold maker for model train kits gave me a suggestion a long time ago--let the machine do the work. So I use small step-overs with small end mills. The tool marks therefore don't show up in the part.

I could do a video about that. I've probably made 30 or more molds in the past 10 years. What in particular are you interested in seeing/learning? As to trains, I picked up the hobby because I was stressed at work (I'm not anymore) and needed something to get my mind off it. Fairly quickly I discovered I loved to design and create projects, and along the way decided I really wanted to be able to make my own injection molded products. So no, I don't have a train layout.

@@JohnSL I don't have any particular interest in model trains, I do think they are interesting and have tried some other people's set ups. I even built a bridge for one just to test myself. Was just thinking it could shine some light on the hobby. If you have your table full of projects keep with them. I find every video you make is interesting even if it is out of my field of interest. Methods and creativity!

@@JohnSL Veryy goodd

When you say the molds only last a hundred castings, are these 3D printed molds? I have another video on that topic. I'm not sure what you're asking about precise molds. Generally it requires a good 3D model and then someone who can machine the molds--assuming you don't have any undercuts.

​@@JohnSL From what I understood from the start your video, is that aluminum molds can make parts around the hundreds, so I wondered how many pieces a mold could make.. So an aluminium mold could go on indefintely? Im not really interested in 3D printed molds, ive seen that they just cant wisthand any production... Regarding precision, I met with a friend, who has a CNC that was used to make aluminum molds for shoe soles, and I wonder what I should look for in a CNC to be able to machine molds for injection of high impact polystyrene for detailed figures character kits, and start a business creating these plastic model figures. I'm trying to find out how to have figures of similar quality to what Gamesworkshop manages to do, so i question myself how precise must the machine be to achieve this result. I have seen quite a few of your videos and they added much knowledge to me already, thanks a lot! Got curious about what injector machine I should get to start this business, now that I know that there is the possibility of machines that eject the parts automatically.

Aluminum molds can often produce 10K to 100K parts before they start to wear. In my case, the parts I wanted to make didn't have much demand--on the order of hundreds of parts. So it was about demand, rather than the life of the mold. For miniatures, there is low-temperature injection molding process that uses rubber molds: www.siocast.com/siocast-for-miniatures/. While their machines are expensive, there are some companies who own their machines and will make molds and parts for other companies. Here is one company I've heard of that offers this as a service: zealotminiatures.com/injection-moulding/. One advantage of this technology is that it allows for some undercut. Additionally, you don't need to design a mold with a very complicated parting line, as would be required for a metal mold for miniatures. If you don't absolutely have to use HIPS, this is a much lower-cost way to get started.

@@JohnSL the whole proprietary plastic/resin from siocast, and the fact that the material doesn’t work with tipical plastic glue is a big turn down strategically for my vision of business. I’d rather use other materials such as pewter or even highgrade 3D printing than their solution. The undercut limitation doesn’t imideately bothers me. The costs for starting the business is something that I’ll have to account for, and the most important cost that I just can’t find is how much the metal molds would cost…

Polystyrene, which is the standard for most model kits as it's easy to glue and you don't need something like ABS.

Yes, I did all the work: CAD, CAM, machining, and injection molding. Most of these were parts I wanted to make and were not profitable, as the volumes were very low. But they were fun to make. Doing this for yourself isn't really cost effective unless you sell at least several hundred and can charge enough.

@@JohnSL You can send your e-mail?

For molds like these, it really isn't that much of a problem, so I don't worry about it. Where it will matter is when I get to automatic molds. And in those cases, there are tricks you can use to get it to stick more to one side.

It depends on the material. The polystyrene pellets I purchased from Tichy Train Group. He doesn't advertise that, so I'm not sure if he's still doing that. Generally it's hard to buy less than about 55 pounds of pellets of a single type and color. So I buy 3D printer filament and then use a chopper from an earlier video to chop the filament into pellets. Yes, that might be a little more expensive. But not that much, and I can get a lot more variety of pellets that way. This works as long as the plastic you want is available in a filament roll.

I believe it's 2 tons (imperial).

@@JohnSL can you tell me what model it is?

I was thinking the same thing. Wondering if the metal soaking up the heat necessitates continual tweaking of parameters.

From what I heard molds get warm, but that's a good thing. Molds work better when they're warmed up so you only need to do it at first and then they stay that way once you have a rhythm.

Eventually. The more plastic being injected into a mold, the faster it heats up. These molds have so little plastic that it would take a very long time (probably hours) before they got too warm to hold. But yes, as molds heat up, the plastic flows more freely, and therefore requires less injection pressure. It's actually a good idea to heat molds that have lots of details, but the aluminum dissipates the heat very quickly, so pre-heating the molds doesn't actually help that much.

Yes, I do make molds for other people as well as parts. You can contact me by click on the About section of my KZfaq page and then there is a button that will show my email address. I'm located on the East side (Seattle area).

I could not find the "About section" on your KZfaq page

kzfaq.infoabout

I don't know, as I purchased mine used. You'll need to contact A.B. Machinery: www.abplasticinjectors.com/ab-150