Nice work! I am thinking of something similar, except using air cylinders- a 1 1/2" bore, 5" stroke double acting cylinder is $95 and would eliminate a LOT of machining, plus the expense of the motor. It might also eliminate the 2-ton jack down below. There would be lots of engineering required to get the sizes right, but I'm thinking that increased simplicity= more machines=more recycling.
Great video guys! I love the engineering and simplicity to keep the build costs down. I did notice the the dimensions for the hollow bar (with machined keyway) look to be incorrect - it looks more like >40mm OD? Loving your work!
Hi trentineer. Thanks for the comments! Yes, the low cost was an important requirement for this project 🙂 About the OD for the pulley axis, it is 36mm. In the video it is made from different parts (nuts and hollow bar), but it would work better if you make it from a single bronze part (as explained at the end of the video)
Major problem with the bottom mold press plate is it doesn't stay horizontal as it retracts which most likely will drop your mold on the floor damaging it when the press plate is retracted. Another thing is that the bottom jack mount plate is questionable whether or not it will eventually develop a depression due to being under constant high pressure, bridging should be added under the bottom jack mounting plate.
This thing will tear down itself by its generated force if the volume of the injection is not the volume of the barrel (and the switch is not triggered) Why you don't use a VFD with current limiter in here?
Hi Friedrich. Thanks for the feedback! I'm interested to know specifically what you mean by "tear down". Have you noticed any weak points in the machine that should be improved? About the volume, if the injection volume is less than the barrel volume, then the piston stops and the belt slips on the pulley leaving the motor to keep moving. At this moment the operator should stop the motor, keep the pressure a few seconds and then turn it back to release the pressure. About the limit switches, yes, they must be very well installed so that they are triggered. If they don't trigger, can damage the screws that hold the switches in place. Then, the screw will keep moving and stop on one of its ends. Then the belt should slide on the pulley avoiding further damage. On the other hand, we thought of the use of VFD's but those are a bit expensive and we wanted to keep the budget low. Also, they work only for speed control, which I think is not completely necessary for the injection, I think the faster, the better. So I'm using the motor to the maximum without any variation. Or you meant to use the VFD as a high voltage limiter to control voltage spikes? I would love to hear more about what you think. Best, Andrés
@@eltornillotaller6813 Hi Andrés - thanks for coming back! I think there are no weak points in the mechanics as far I can see. Only the drive system i have doubts about- "belt slipping" is not the most sustainable overload protection i think. Every VFD has a overcurrent limit which you can set and the motor will stop. If you set it as an output on the VFD you get a signal that can go into a delay timer and auto-reverse the motor. Also you can display the current used at the moment - which is very helpful to determine your injection pressure and find errors with the plastic/machine/mould. The cheap option is sth. like a GRI8-04 to stop (and reverse) the motor - its used in some shredders too.
Hi @@FriedrichKegel. Thanks for all that information! I'll search and study those components to see how I can include them in the machine. I think you are right, a belt slipping is not the best way to control the pressure/overload, for now it's working in this first design but definitely its something to be improve. Thanks again, Andrés
I understand that in industrial injection molding machines the main screw piston increases in diameter as you go down and thus creates friction between the plastic and the wall of the tube, melts the plastic and as such doesn't need a heating mechanism or at least significantly reduces the requirements for heating. Is such a thing possible on a smaller scale such as this as well?
Your "spacers" would be more helpful if they were adjustable to accommodate axial tolerance issues. Your dimensions stated in the video do not seem to line up where two parts are meant to join together they should have the same inner diameter and outer diameter on the other part (25mm, 28mm, 32mm and 36mm). Your bearings are very sloppy, your shaft size should be as close to a press fit as you can for the inner race and machining a step on both sides of the threaded tube assembly at a known dimension would make spacing and adjusting easier. Making sure the bearings are well seated and well lubricated with help with life span. Greasing and adding grease fitting for the acme threads will help with excess wear. The general design is good but some parts need a bit more precision. Using one or two hubs for a heavy duty trailer could be a good choice for having a precise housing that can hold standard bearings.
Incredible project guys! Thank you for such useful experience.
El Tornillo 🥰
Thank you very much Andres! And the PP team to find these new ways of making the community more diverse and there for stronger
Thanks Andres and team! 👏🔥
Nice work! I am thinking of something similar, except using air cylinders- a 1 1/2" bore, 5" stroke double acting cylinder is $95 and would eliminate a LOT of machining, plus the expense of the motor. It might also eliminate the 2-ton jack down below. There would be lots of engineering required to get the sizes right, but I'm thinking that increased simplicity= more machines=more recycling.
❤ very simple way to reduce the cost of this valuable injection machine
Absolutely amazing, it was a pleasure meeting Andres in Bogota. Hope to meet Mattia and the team soon too!! Much love from 🇵🇪❤
We hope so too soon :)
Amazing work Andres and team !
Great video guys! I love the engineering and simplicity to keep the build costs down.
I did notice the the dimensions for the hollow bar (with machined keyway) look to be incorrect - it looks more like >40mm OD?
Loving your work!
Hi trentineer. Thanks for the comments! Yes, the low cost was an important requirement for this project 🙂 About the OD for the pulley axis, it is 36mm. In the video it is made from different parts (nuts and hollow bar), but it would work better if you make it from a single bronze part (as explained at the end of the video)
Major problem with the bottom mold press plate is it doesn't stay horizontal as it retracts which most likely will drop your mold on the floor damaging it when the press plate is retracted. Another thing is that the bottom jack mount plate is questionable whether or not it will eventually develop a depression due to being under constant high pressure, bridging should be added under the bottom jack mounting plate.
Great video, one thing add the link to the music great background music 🎉
Thank you for your hard work.
Awesome concept!
Thank you for sharing the knowledge and making this detailed video.
Cool!
Felicidades Andrés, increíble 🎉
This thing will tear down itself by its generated force if the volume of the injection is not the volume of the barrel (and the switch is not triggered)
Why you don't use a VFD with current limiter in here?
Thanks Friedrich! Very valuable feedback for El tornillo and anyone replicating this machine. Hopefully the switch doesn't fail us too often.
Hi Friedrich. Thanks for the feedback!
I'm interested to know specifically what you mean by "tear down". Have you noticed any weak points in the machine that should be improved?
About the volume, if the injection volume is less than the barrel volume, then the piston stops and the belt slips on the pulley leaving the motor to keep moving. At this moment the operator should stop the motor, keep the pressure a few seconds and then turn it back to release the pressure.
About the limit switches, yes, they must be very well installed so that they are triggered. If they don't trigger, can damage the screws that hold the switches in place. Then, the screw will keep moving and stop on one of its ends. Then the belt should slide on the pulley avoiding further damage.
On the other hand, we thought of the use of VFD's but those are a bit expensive and we wanted to keep the budget low. Also, they work only for speed control, which I think is not completely necessary for the injection, I think the faster, the better. So I'm using the motor to the maximum without any variation.
Or you meant to use the VFD as a high voltage limiter to control voltage spikes?
I would love to hear more about what you think.
Best,
Andrés
@@eltornillotaller6813 Hi Andrés - thanks for coming back!
I think there are no weak points in the mechanics as far I can see.
Only the drive system i have doubts about- "belt slipping" is not the most sustainable overload protection i think.
Every VFD has a overcurrent limit which you can set and the motor will stop. If you set it as an output on the VFD you get a signal that can go into a delay timer and auto-reverse the motor.
Also you can display the current used at the moment - which is very helpful to determine your injection pressure and find errors with the plastic/machine/mould.
The cheap option is sth. like a GRI8-04 to stop (and reverse) the motor - its used in some shredders too.
Hi @@FriedrichKegel. Thanks for all that information!
I'll search and study those components to see how I can include them in the machine.
I think you are right, a belt slipping is not the best way to control the pressure/overload, for now it's working in this first design but definitely its something to be improve.
Thanks again,
Andrés
Amigo, buenisima idea! Ahora si tuviera un motor de 2HP - 1400RPM, de cuanto podría ser el reductor 1:20?
I understand that in industrial injection molding machines the main screw piston increases in diameter as you go down and thus creates friction between the plastic and the wall of the tube, melts the plastic and as such doesn't need a heating mechanism or at least significantly reduces the requirements for heating. Is such a thing possible on a smaller scale such as this as well?
We use those type of screws on our Extrusion machine community.preciousplastic.com/academy/build/extrusionpro
Your "spacers" would be more helpful if they were adjustable to accommodate axial tolerance issues. Your dimensions stated in the video do not seem to line up where two parts are meant to join together they should have the same inner diameter and outer diameter on the other part (25mm, 28mm, 32mm and 36mm). Your bearings are very sloppy, your shaft size should be as close to a press fit as you can for the inner race and machining a step on both sides of the threaded tube assembly at a known dimension would make spacing and adjusting easier. Making sure the bearings are well seated and well lubricated with help with life span. Greasing and adding grease fitting for the acme threads will help with excess wear. The general design is good but some parts need a bit more precision. Using one or two hubs for a heavy duty trailer could be a good choice for having a precise housing that can hold standard bearings.
Hydrolic power pack information give