POV-Ray : Newsgroups : povray.general : REQUEST Server Time
31 Oct 2024 19:12:17 EDT (-0400)
  REQUEST (Message 11 to 20 of 31)  
<<< Previous 10 Messages Goto Latest 10 Messages Next 10 Messages >>>
From: Sven Littkowski
Subject: Re: REQUEST
Date: 15 Jan 2016 18:53:11
Message: <56998667@news.povray.org>
Point taken, Scott. Is this sketch good enough?


Post a reply to this message


Attachments:
Download '2.jpg' (67 KB)

Preview of image '2.jpg'
2.jpg


 

From: Sven Littkowski
Subject: Re: REQUEST
Date: 16 Jan 2016 13:08:11
Message: <569a870b$1@news.povray.org>
Hi Scott, did you see my sketch?


Post a reply to this message

From: scott
Subject: Re: REQUEST
Date: 18 Jan 2016 03:43:24
Message: <569ca5ac@news.povray.org>
> Point taken, Scott. Is this sketch good enough?

Yes that's much better. The section view attached shows the minimum 
number of dimensions needed to fully constrain this shape (the CAD 
software will give an error if you try to overconstrain the layout).

A word of warning about getting it 3D printed, you will want to make 
sure that the surface finish is smooth enough, otherwise I imagine 
you're going to get bits of sausage meat stuck in the plastic which will 
probably be very difficult to clean out. Also I don't know what sort of 
pressures you're talking about, but some of the cheaper 3D printers 
don't give parts that are very strong at all. And, check the material 
used, as some absorb water very readily, expand and will change shape or 
warp over time.

Personally I would get this part turned on a lathe from a bit of 
stainless steel bar. It will last forever, be much stronger and far more 
hygenic. I doubt the price would be any more than a decent quality 3D 
print. The CAD software tells me it would weigh about 200g if made from 
steel.


Post a reply to this message


Attachments:
Download 'prt0001_stl.zip' (104 KB) Download 'section.png' (13 KB) Download 'solid.png' (116 KB) Download 'stl_mesh.png' (225 KB)

Preview of image 'section.png'
section.png

Preview of image 'solid.png'
solid.png

Preview of image 'stl_mesh.png'
stl_mesh.png


 

From: Sven Littkowski
Subject: Re: REQUEST
Date: 18 Jan 2016 11:59:08
Message: <569d19dc$1@news.povray.org>
Hi, thanks a lot! Yes, that is the part I need.

I live in Jamaica, and here is no place that can shape or make steel in
that shape. Sad for me.

I think, the best way for me to go, is to talk to Shapeways if they can
3Dprint it with some material that is smooth and pressure-strong. I
agree, there will be some pressure. But not as much as inside the
grinder. That part is mounted outside, where the grinded meat leaves the
machine.


Post a reply to this message

From: Sven Littkowski
Subject: Re: REQUEST
Date: 18 Jan 2016 12:01:08
Message: <569d1a54$1@news.povray.org>
And I want to thank you a lot for your time and work, Scott.


Post a reply to this message

From: Stephen
Subject: Re: REQUEST
Date: 18 Jan 2016 12:27:55
Message: <569d209b$1@news.povray.org>
On 1/18/2016 4:59 PM, Sven Littkowski wrote:
> Hi, thanks a lot! Yes, that is the part I need.
>
> I live in Jamaica, and here is no place that can shape or make steel in
> that shape. Sad for me.
>

Come on! You can't expect anyone to believe that. I worked at D&G, years 
ago and I could have got you one turned there, then. Ask your Helper or 
security and I bet that they will know where the machine shops are.


-- 

Regards
     Stephen


Post a reply to this message

From: Sven Littkowski
Subject: Re: REQUEST
Date: 18 Jan 2016 17:03:57
Message: <569d614d@news.povray.org>
Yes, here are machine shops, but Jamaica is a very poor country (thanks
to its incapable and corrupt, partially even criminal government). The
machine shops here are very limited in what they can do (type of
machines they can afford), and also very limited by metal types.

Some weeks ago, I tried to find a machine shop that can create a
fast-rotating disc for a machine I wanted to build to make powder out of
empty plastic bottles (see attached render image), and they couldn't do
it. I went to over 20 machine shops until I gave up. I learned, what
they can do, and what not.


Post a reply to this message


Attachments:
Download 'sl - roto rasp a.jpg' (858 KB)

Preview of image 'sl - roto rasp a.jpg'
sl - roto rasp a.jpg


 

From: Stephen
Subject: Re: REQUEST
Date: 18 Jan 2016 17:55:24
Message: <569d6d5c$1@news.povray.org>
On 1/18/2016 10:03 PM, Sven Littkowski wrote:
> Yes, here are machine shops, but Jamaica is a very poor country (thanks
> to its incapable and corrupt, partially even criminal government). The
> machine shops here are very limited in what they can do (type of
> machines they can afford), and also very limited by metal types.
>

You won't get any arguments from me on that assesment. :-(

> Some weeks ago, I tried to find a machine shop that can create a
> fast-rotating disc for a machine I wanted to build to make powder out of
> empty plastic bottles (see attached render image), and they couldn't do
> it. I went to over 20 machine shops until I gave up. I learned, what
> they can do, and what not.
>


That is a different kettle of saltfish. ;-)
Your grinder blade is quite complicated. You would need a template to 
stamp out the body then you would have to weld the uprights. A prototype 
would be hard and expensive to make. On the other hand, the part you 
need for the meat grinder is simple. I don't think that the pressure 
justifies surgical stainless steel. Just a metal that would not corrode. 
I agree with Scott that a piece made from printed plastic might be 
unsuitable for your needs. You would never know what beasties were 
hiding in the crevices or when its structural strength would fail.
I would take the drawing you did for Scott and ask about that.
I have a similar problem with a pressure cooker. The plastic well that 
the relief valve sits in. Sheared off and I have a large pot with a 
whistling lid, now. Even at the low-ish pressure of 15 psi I would not 
contemplate using a printed part unless it was properly engineered.
It is a great idea but  a bit iffy in practice.


-- 

Regards
     Stephen


Post a reply to this message

From: Sven Littkowski
Subject: Re: REQUEST
Date: 18 Jan 2016 19:12:52
Message: <569d7f84$1@news.povray.org>
I heard, a common practice in 3D printing is, to use acetone to smoothen
surfaces afterwards where applicable. I joint some 3D Printing groups on
Facebook.

Besides, I am really not so sure, how high the pressure on that plastic
part is. The grinder came with a number of other plastic parts that can
be mounted at the same location outside, where I want to mount this
plastic part. And they have the same wall thickness (strength) as the
part Scott and I developed. I think, I still want to give a try.

But in regards of the micro fauna and the fact, that 3D printing today
(when done with a layer printer) is having a rough outside, I give you
the point easily. I hope, with some acetone I can smoothen the inside.
And otherwise, good cleansing afterwards and also before, each time.

---------------

I am still trying to find a solution in regards to my round grinding
blade. If you know any good machine shops, please let me have their
contact information. I am aware it will take some money, but need to
find out, how much. Thanks.   :-)


Post a reply to this message

From: scott
Subject: Re: REQUEST
Date: 19 Jan 2016 03:18:27
Message: <569df153$1@news.povray.org>
> Yes, here are machine shops, but Jamaica is a very poor country (thanks
> to its incapable and corrupt, partially even criminal government). The
> machine shops here are very limited in what they can do (type of
> machines they can afford), and also very limited by metal types.
>
> Some weeks ago, I tried to find a machine shop that can create a
> fast-rotating disc for a machine I wanted to build to make powder out of
> empty plastic bottles (see attached render image), and they couldn't do
> it. I went to over 20 machine shops until I gave up. I learned, what
> they can do, and what not.

I would be very interested to hear what they can do, if they can't turn 
this simple part for you. Even doing it freehand on a very basic 
metalworking lathe I can't imagine it taking more than an hour.

Your cutter disk thing is completely understandable, I can only imagine 
the reaction from our guys in the machine shop here at work if I took 
that design over to them :-O


Post a reply to this message

<<< Previous 10 Messages Goto Latest 10 Messages Next 10 Messages >>>

Copyright 2003-2023 Persistence of Vision Raytracer Pty. Ltd.