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Hi, leider hebe ich gerade lein Video zur Hand. aber schau mal bei Youtube unter dem Suchbegriff “DIY Shop Press”
Hi, the press is nothing else than a ordinary car jack and some steel bars.
You can build it by yourself. You need a hydraulic (or spindle) car jack and some big U-Profile steel Bars.
The press I have has a height variable press table but this is not really needed.
you can adjust the distance between the mold and the car jack wit some pieces of wood.
you also can built the press with the car jack under the table, so you press against the upper bar.
Here is an example picture of the press I use.
Hi Duc, pressing molten plastics into moulds is really easy. You need a inner and a outer mold (for bowls) or a mold and a flat plate. than you calculate the volume of your workpiece (outer mold minus inner mold) and then you can calculate the needed amount of shredded plastic.
Spray some mold release in the outer mold. I use ptfe spray.
then you put the outer mold in the oven and heat it up to the melting temperature of your plastic.
When the mold is hot add some plastic and let it melt. In the first step I add 4-5 spoons of material, so that the bottom of the mold is even filled. Add not too much or you will have more bubbles in your workpiece. Repeat adding and melting until the mold is full. when the last pieces are molten, use a gas torch or a heatgun to pop the bubbles on the surface of the molten plastic.
then spray mold release on the inner mold and put the inner mold in the oven too to preheat it.
When it´s done put the molds under the press and press the molds until the plastic is reaching the edge of the mold. let the plastic cool down a bit and apply
more pressure bit by bit. while the workpiece is cooling it will shrink a lot. to prevent cracks or airpockets apply more and more pressure until the workpiece ist cooled down.
Then release the pressure and remove your part out of the mold.
a winch motor is not the best solution for the shredder, but the cheapest.
It works very well and you can shred a lot with it before it gets hot.
Then you can drink a coffee to let it cool down a bit 🙂
Later when you have earned some money you can sell the shredder and built a new one with a bigger (industrial) motor.
I looked for the biggest possible winch motor i could get. I think my winch could lift up to 1300kg and costs around 160€ on eBay.
Hi, I ordered the same book the day before.
I hope there are some good inspirations in it or in the other book I ordered.
I don´t think I´ll get the time to tinker with injection molding in the next few weeks but the wintertime is long and I have a lathe 😉
Greetings from Saarland
I think this could be a good addon. Maybe it is possible to combine the shop press with the injection molding machine…
I´ll take some thoughts about this 😉
yes it is a lot of fun to work with. Today I presented the Setup in Neunkirchen, a city next to my location. I carried it to the market place, built it up and started my presentation. I got a lot of good response for this workbench , the idea behind it and my products.
I met a lot of interested people and I think that this is a really good start for this project. I made contact to 2 schools and I think I can present the workbench there too.
Maybe it is possible to start some cool projects wit their pupils.
Hi, I used this motor.
This winch motor is so powerful that it bent my Shredder axis coupling when I tried to shred 6mm thick PMMA plates 🙁
The spool from the powerful 1800W (500/1000kg Version) motor is stacked on to an 27mm hex bar. you can easily pull it off.
Thank you very much.
I recently tried some different things, like a stool, a clock and a planner.
and here are my tools:
In my next project I will combine them on a beer bench 😉
Here are some better pics of the bowls I made
A few weeks ago I saw a Video on YT in which some resin castings are made.
They used a blowtorch to pop all bubbles on the surface after casting.
I tried the same after I melted the printed parts, just before I pressed it into the mold.
With success. All bubbles popped and I got a smooth surface.
After a little bit of cooling I filled the inner Bowl with boiling hot water to slow down the cooling process, because last time I got some small cracks on the surface.
I hope it will work.
I am very excited and I can´t wait to see how it comes out of the mold.
Yes, I saw this video. For this reason I wanted to built the same Shredder.
I ordered the same motor and I hope that is enough power for crushing the 3D printed parts.
Nope. I ordered the Parts for the 27mm hex bar version.
I hope that it will work with the slow 1,5KW 30rpm motor I ordered.
Otherwise I´ll sell it on eBay and built the stronger one 🙂
I´ll give s2019´s idea with the shop press crushing a try tomorrow.
Thanks you for these tips.
I hope that my laser parts for the shredder arrive this week, so that I can granulate the parts and then dry it before melting.
I think most of the air bubbles come from the infill pattern in the printed parts.
maybe it is a good solution to heat up the printed parts to around 50 degrees Celsius for an hour or so to dry them before raising the temperature up to the melting point.
Here are the first results