Stan

From your first and second picture it looks like you are injecting through a small hole so your part is trapped in the top piece. Are you doing that to help remove the part from the bottom pieces? You could add some jack screws in the perimeter frame to help separate the stack.

Yeah, a little more grind and polish to smooth the surface would help as well.

Did you see the plastics melting temperature chart on the PP site  https://preciousplastic.com/en/videos/plastics.html ? It shows that the common plastics tend to stay fairly viscous even when they melt. Not sure how pouring them will work. I think you will need to press them in some fashion. Also note that at those temperatures you should have s…[Read more]

As you tighten the bolt, the heaters should be compressed against the tube before the you lose the gap in the cylinder portion. It should be tight enough that you can’t twist the heater on the tube with your hand.

I can’t see what holds the bottom heater on. Is it just the spring of the band? I’m guessing that what is turning is the bottom pipe…[Read more]

I don’t know why PP chose to clamp the thermocouple under the heaters. You really don’t want to measure the heater temperature, you want to measure the pipe. Adding a separate hose clamp to mount the TCs would have been an easy alternative. This is especially true of the typical low PID/SSR/TC kit that comes with a threaded mount for the TC tip.…[Read more]

The thermocouples are the two thin wires with the stainless braid on the outside. Looks like they are mounted by being clamped under the heater bands. I think that’s the way the Precious Plastic design recommends but there can be issues. Without breaking the thermocouple wires, do they feel like they are clamped snugly (gentle wiggle does not move…[Read more]

I can’t see how the thermocouples are mounted in those pictures but I would not run more plastic until the temperature control is working well. Can you take a picture of the two thermocouples as they are mounted on the tube?

For heat welding, look at some of the work @imuh did https://davehakkens.nl/community/forums/topic/v4-adhesives/#post-139270  .
Looks like most of you structure is made from angle stock. You could either press directly to that shape or make flat stock and bend it by reheating and press into a mold. You may want to look through some of the t…[Read more]

If you are going to use an oven or a custom heated enclosure, I would find a way to have a lot of convection in there to help eliminate hot spots that will burn the plastic. Think along the lines of a large air fryer or a hotter version of a dehydrator. You can do this with a metal fan blade with a shaft to a motor outside.

I’m looking forward to…[Read more]

The central hole for the threaded rod may be a challenge. If you look at some of the furniture making threads, there have been some good results using heat welding for assembly.

Making parts in a press with a form and perhaps a hydraulic shop press should be worth trying.

I would start taking some measurements with a multimeter.
– Confirm that both PID’s are producing the right output that matches what the SSR needs (the PIDs look identical but have different dash numbers for the different type)
– Confirm you got mains power coming to the SSR and check whether it switches on.
– Check continuity in your heater…[Read more]

What Olivier said.
Also, you said thermistor, did you mean thermocouple? I think the sensor hookup for resistance thermometers is a little different from the thermocouple models.

When you say not working, what does that mean? Does the PID show a reasonable PV temperature? When you set the temperature higher, does the output light come on? Does…[Read more]

As I mentioned, with a big open cavity mold may not need as much pressure to fill but pressure also helps reduce voids.

…………..You can always work your way up by making the pallina ball first

To estimate the material, just get an estimate of the volume of the part (for a rectangular beam just a product of the width, thickness and length) and multiply it by the density of the plastic you are using. For example for HDPE the density is a little less than the density of water (1g/cc) so a 2x2x100 cm beam would use a little less than 400g…[Read more]

If you are following the guides in the download kit https://preciousplastic.com/en/videos/download.html  , the recommended starting temperatures for PP are in the 190-210 C range. Your temperatures (if they are in C) are way off to the point of potentially generating some nasty fumes. Be careful. I don’t understand some of your temperature t…[Read more]

The shredder is fun (and therapeutic). I think there would be a lot more recycling if people could watch that shampoo bottle being shredded.

The extruder machine is the only one that needs small plastic flakes. The other machines can use larger, hand cut pieces. Sometimes (especially in the press machine) you get more interesting color patterns…[Read more]

In the PP injector design, when you increase the diameter of the barrel, the pressure you can generate decreases and given the linkage geometry it can be challenging to get it back up. Pressure may not be that important for a large volume mold like a bocce ball, but making smaller parts may be harder. For large volume, I would consider the rack…[Read more]

So you are off the grid and need a motor for your shred-extrude-o-matic. What to do?
The neighbor’s car didn’t need A/C anyway…..
https://www.youtube.com/watch?v=SxqyfB83tSo

https://bazar.preciousplastic.com/?category=machines
But why start with the shredder?

Glad to hear you stuck with it and are in production. 12 per hour is a very good throughput. That’s a nice wax comb.

The injection machine is relatively easy to build without a lot of resources but you will need the heaters and temperature controller(s). To use the injection machine you will need to make some molds. These can be simple bolted together or welded for simple geometries, or can become complex machine parts. There are also size limitations for the…[Read more]