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This article should have one of those boxes that states "needs to be cleaned up."

Yes. Perhaps we can add subsections, most notably one for "Extrusion Cooking." --MYTom 22:58:09, 2005-09-02 (UTC)

the big addition...[edit]

The big addition to this article from a few months ago sure seems like a text dump from some book or another. --jpgordon∇∆∇∆ 02:33, 4 September 2005 (UTC)


I think that plastics extrusion should be merged into this article. And it should either be referred to as "Polymer Extrusion" or "Plastic Extrusion", but not "Plastics Extrusion". --PrecisionEx 17:41, 15 September 2006 (UTC)

External Link Spam[edit]

I just removed an external link that i considered to be spam. Wikipedia is an encyclopedia, not a free source of advertising, not a link directory. Wikipedia is not for spam! Please do not link to external sites if they offer ABSOLUTELY NO educational value, or if your intentions are clearly only for promotional value of the linked site. This does not mean that you cannot link to 'commercial' sites, only that the linked site must contain relevant educational content that complements the article and contributes knowledge. You are encouraged to add content to wikipedia articles, but please read Wikipedia's tutorials and generally accepted practices in regards to editing articles. If you feel that the link was unfairly removed, please feel free to discuss it here. Thank you, --AnTony 04:25, 18 September 2006 (UTC)

I just added a few links to sites that i consider to be relevant, content rich, and generally good sources of information. These sites being; Society of Plastics Engineers, eFunda - Extrusion, and Strictly-extrusion. --AnTony 05:05, 18 September 2006 (UTC)
I can't even view Strictly-Extrusion without JavaScript, and WP isn't a directory to business associations like Society of Plastics Engineers, so removed them. Femto 15:52, 2 November 2006 (UTC)

Food section[edit]

The second paragraph of the Food section looks much like copy-and-pasted. There is a "course" mentioned that has obviously nothing to do with this article. -- 11:37, 12 May 2007 (UTC)

Removed [1], thanks for pointing it outrefref. Femto 16:18, 12 May 2007 (UTC)

I have added more detail to the food section obviously this only applies to my area of knoledge (pet food) and comments welcome —Preceding unsigned comment added by Malunas (talkcontribs) 14:51, 10 April 2009 (UTC)

Right now there is an expansion template in the section. I know nothing about that application, but do you think it could still use more expansion? Wizard191 (talk) 15:03, 10 April 2009 (UTC)
Definite need for more expansion. This technique is ever-growing in the food industry, but the public is hardly aware the process even exists. There is some resistance to this technique given its novelty, but in limited circles. I'm working on making this section more neutral and better-balanced presently. For example, I've toned down the buzzword-wizardry that was getting intermixed with the 'food benefits' of the process. E.g.: How does "starch gelatinization" stand as a remote benefit for a consumer? It doesn't. It's really only beneficial to manufacturers. I moved such terms up out of the benefit list. Ideally this food section should eventually have its own page. Koyae (talk) 14:48, 23 April 2011 (UTC)


I removed the following because there isn't enough context. If someone can put it into context that would be great.

Extrusion is also a very important unit operation in shaping a catalyst. The shape of a catalyst is directly related to its working conditions. A high specific surface can be obtained by extrusion.

--Wizard191 (talk) 02:18, 6 May 2008 (UTC)

Road marking compound[edit]

"Painted" road markings are often done with extruded two- or three-component compounds. Thermoplastics are also common. This is a low-pressure, high-flow process with very good contour and thickness control. Extrusion has more or less completely replaced the older "sliding mold" method. Benefits are much better economy, higher speed, and general appearance.

I don't think that this is actually a form of extrusion. I think it is closer to emulating something like a 2 part epoxy setup you might buy at your local hardware store.

--Wizard191 (talk) 02:31, 6 May 2008 (UTC)

See also dispute[edit]

--- Conversation pasted from User talk:Gregbard and User talk:Wizard191 ---

Hi, I see that you are persistent at wanting the toothpaste tube theory link in the extrusion article, however I'm at a complete loss as to how it applies to the article. The toothpaste tube theory article is about theories of law, economics, philosophy, etc., whereas extruding is about a process. What am I missing? Wizard191 (talk) 18:13, 20 May 2009 (UTC)

In every formulation of the toothpaste tube theory, the analogy is that the process in question (i.e. hiring practices, exports, etcetera) behave like the extrusion of toothpaste from a toothpaste tube. The analogy to extrusion applies in each case. Furthermore, for one looking into the subject of "extrusion" the existence of a rhetorical analogy for the process would seem to be a relevant and illuminating fact to include. It's only a "see also" so it really not a big deal. Did you just look at it and think its a joke? It's colorful, but I didn't mean it as a joke, but rather as useful. I had similar experiences with garbage heap of history as well. Be well, Pontiff Greg Bard (talk) 18:38, 20 May 2009 (UTC)
I didn't think it was a joke, I can see that it's a legit article. I also understand that toothpaste is "extruded" out of a toothpaste tube. My problem is the "see also" section isn't the place to place every example of extrusion. Moreover, this link is only refers to "extrusion" in the figurative sense. As such, there absolutely no place for it. If anything were to be done it would have to be listed as a hatnote or put on a disambiguation page, but I don't even think it deserves that. Instead, I recommend you create a redirect out of extrusion theory or extrusion theories. Wizard191 (talk) 23:14, 20 May 2009 (UTC)
As it happens, I have been doing a lot of work organizing articles under the theories category. I can tell you that I will not be creating any "extrusion theories" article, redirect, disambig, hatnote or category any time soon. That all sounds quite dramatic. It seems to me you have a very definite and narrow view of what the proper role of the "see also" section is, which I do not share at all. Apparently you are completely unmoved by the fact that there exist rhetorical and figurative applications of extrusion. That is fine, however, please consider others who may be, an do not limit their experience to your experience. Be well, Pontiff Greg Bard (talk) 23:45, 20 May 2009 (UTC)
My problem is that you are trying to apply the term "extrude" to your theories, but the theories aren't about the process of extrusion. The article states: "This is intended as an analogy to the fact that pressure built up in some finite bounded system needs to be released somewhere or the system will break." It is about "release", not "extrusion". It just so happens that some call the release of toothpaste from a toothpaste tube "extrusion", but it could also be termed "expulsion", "ejection", "discharge", "purging", or just "release". Why don't you add the link to the see also section of those articles? Moreover, the reason the toothpaste expels from the tube is because of a build up of pressure, therefore you should add the link there and to all of its similar terms. Why not breaking, failure, or rupturing? The theory just borrows a easily understandable and tangible example, the toothpaste tube, to explain the idea quoted above; it has nothing to do with the process of extrusion. Wizard191 (talk) 02:16, 21 May 2009 (UTC)
Okay you are now being very puzzling. I checked every single one of those links. Almost all of them are disambiguation pages without any main article about, for instance "ejection, discharge, etcetera" in general. There is an article about "purge." However that concept is not what the toothpaste tube theory is describing. The toothpaste tube theory describes extrusion exactly. Furthermore, the lack of an appropriate alternative only strengthens the case that it is most closely described as extrusion.
It seems you have gone through a lot of trouble thinking about this. Like I said, the toothpaste tube theory describes extrusion exactly. Your alternatives are universally weaker, if not completely inappropriate. At this point I am wondering about what motivates such efforts.
I think it is possible that you see the article as a "physics" article and cannot bear to include any interdisciplinary observations in it? That isn't really an appropriate way to go about a publically editable, general use encyclopedia. I had asked you not to limit it to your view of things. Seeing the connections between things is a measure of intelligence. I would like WP to be as intelligent as possible. Be well, and say, ... let it go man. Think of others. Pontiff Greg Bard (talk) 03:45, 21 May 2009 (UTC)
First off, no personal attacks.
Second, you completely missed my point. It doesn't matter if "expulsion", "ejection", "discharge", "purging", or "release" are disambiguation pages. You are wanting to add the toothpaste tube theory link to the extrusion article because one sentence in your article states that toothpaste "extrudes" from the toothpaste tube. My point is that you could have used any one of the words above to describe the release of the toothpaste from the bottle. Based on your argument, these theories that "act" like an "extrusion" also equally act like the "expulsion" of toothpaste from a toothpaste tube.
Third, it's somewhat sketchy to describe it an extrusion process, as the goal of the packaging is to contain the toothpaste until it's ready to be dispensed and then conveniently allows you to do that by pressing anywhere on the tube. The goal of the opening is to just release the toothpaste, not form it into a specific shape. Do you want to know why it's round in shape? It's because it's the easiest and cheapest to manufacture. As such, I don't even think it's proper to classify it as an extrusion process.
Finally, I am completely open to interdisciplinary concepts, but this is not interdisciplinary. This is you trying to stretch a analogy way too far. Please re-read your sentence from your article: "This is intended as an analogy to the fact that pressure built up in some finite bounded system needs to be released somewhere or the system will break." That's what the article is about, it's not about extrusion.
If you want to continue this debate, please stop using empty arguments like: "The toothpaste tube theory describes extrusion exactly. Furthermore, the lack of an appropriate alternative only strengthens the case that it is most closely described as extrusion." You don't explain why it exactly describes extrusion or directly disprove my argument. Wizard191 (talk) 11:56, 21 May 2009 (UTC).

<-- In my hometown of Chico, CA. We have a state university which comprises a significant minority of the city population. From this culture has arisen many town-gown conflicts. In Chico, we used to have a week long celebration called Pioneer Days. This was a culminating event celebrating local culture, with a parade and other events, etcetera. At some point there were riots, and the university canceled the events. In the intervening years, in the absence of a large culminating event, St. Patrick's Day, and Halloween grew into large events involving as many as ten thousand people. So it is said that the toothpaste tube theory applies to people's human spirit and events like parties and festivals. "If you squeeze one end, it comes out the other." This is what originally inspired me to want to write this article.

I have avoided any personal attack, however, I am wondering about the causes of this whole issue. I merely would prefer the article wasn't an orphan. It seems to me to be perfectly obvious that A) the "toothpaste tube theory" or the "toothpaste tube effect" is completely synonymous with extrusion and B) extrusion is excellently exemplified by the example of squeezing a toothpaste tube. Furthermore, I believe that any "reasonable person of normal sensitivity" really would have no choice but to agree (I only use that term because it seems to be a legal standard in many places).

I see that "extrusion" is an article you started and you have given several "alternative" terms none of which so precisely describes the concept in question. Are you under the impression that this is a zero sum type of things here? If you can find some alternative term, then extrusion is off the hook? I have added a see also section in ejection, which is the only other one that makes any sense. I will take a closer look at expulsion. However, that doesn't mean extrusion is "off the hook" somehow. You state that you believe my claim is because of "one sentence" in the article. Is this a proper way to analyze things? One sentence actually does the trick quite frankly. (Extrusion is actually mentioned elsewhere in the article, as well as in the source for the content). Furthermore, extrusion as a concept is present in all the formulations.

You even claim it as a sketchy description because an expulsion of toothpaste isn't in any particular shape, and therefore not an extrusion. First of all, it IS in a specific shape, it's round and the appropriate size for a toothbrush. Second of all, do you really hold the notion that an expulsion isn't an extrusion unless the shape of the extrusion was predetermined? That makes absolutely no sense at all. That view is consistent with a very narrow view of things, rather than a broad one. A break in the side of a tube also extrudes toothpaste.

"If you squeeze one end , it comes out the other." is a very popular formulation of the toothpaste tube theory. In your mind I have taken the analogy "way too far." I'm sorry but that makes no sense at all. It is absolutely no stretch at all to say that the toothpaste tube theory is an analogy to extrusion. I am very puzzled by your view.

I recently read Zizek's Sublime Object of Ideology which describes how ideology shapes our beliefs on a level between conscious and unconscious. I cannot help but think that this is an example, where someone who has studied extrusion on more than a causal level cannot see how the tooth paste tube is a perfect example of it. I find the whole thing fascinating. I wish you well. I think this whole thing is way too much to go through over a link in a see also section. I, for one, have certainly dropped issues over less. Pontiff Greg Bard (talk) 17:51, 21 May 2009 (UTC)

I have requested a third opinion because we cannot seem to see eye to eye on this. Wizard191 (talk) 18:05, 21 May 2009 (UTC)

--- End of paste ---

Third Opinon - A third opinion was requested at the project page WP:Third opinion. I am here to provide an opinion in accordance with Wikipedia policies and guidelines that will encourage the formation of consensus and help us all to produce a better encyclopedia.

Working It may take some time to review your discussions, check for sources (if necessary), review the aforementioned policies and guidelines and write the opinion. I will post my opinion here shortly, but in the meantime please continue a constructive debate. Bigger digger (talk) 18:59, 21 May 2009 (UTC)

Firstly, it's normal to keep a dispute about an article on its talk page. This means that other editors involved with the article will have an opportunity to comment and also serves as a record of the debate for future reference. I'll take the liberty of pasting it above, feel free to revert if you think this is inappropriate. Bigger digger (talk) 19:34, 21 May 2009 (UTC)

The first thing to do in a dispute is to refer to the policies and guidelines available. A quick search reveals the WP:SEEALSO. The relevant portion to consider is "A reasonable number of relevant links that would be in the body of a hypothetical "perfect article" are suitable to add to the "See also" appendix of a less developed one." It is clear therefore that the See also section is for links that are related to the article but not yet incorporated into it. I don't think anyone would expect to find a section on toothpaste tubes, which aren't linked, let alone information about a social or political theory, in an article about extrusion, the manufacturing process. The See also section is designed to benefit the article, not create wikilinks to other tenuously related articles.
Above, User:Gregbard suggests the insertion of the toothpaste tube theory link to ensure that the article is not an orphan. That logic is the wrong way around, as the See also section is not for the use of every article that links to it. It is fine for TTT (to abbreviate) to link to extrusion but that doesn't mean it has to have a link back. Although orphan status is not ideal, it doesn't diminish an article. An article stands on the strength of its sources. Which leads to the assertion that "In every formulation of the toothpaste tube theory, the analogy is that the process in question (i.e. hiring practices, exports, etcetera) behave like the extrusion of toothpaste from a toothpaste tube. The analogy to extrusion applies in each case." I have checked the sources accesible online on the TTT article and neither uses the word extrude. The way the toothpaste leaves the tube is not actually relevant, it is the fact that pressure (or changes) forces it out. This is reinforced by the edits to the article which suggest User:Gregbard specifically altered the wording of the finished/completed article to include an extrusion link, see this diff.
Finally to discuss the following statement: "It is absolutely no stretch at all to say that the toothpaste tube theory is an analogy to extrusion." It is a stretch to say that toothpaste tube theory is an analogy to extrusion. The point is that toothpaste tube theory uses a tube of toothpaste as a metaphor and has no comment on the method by which toothpaste leaves the tube. I might have tied myself in knots in that last sentence(!), but it is clear that a See also link in the extrusion article is not merited. I look forward to reading your responses. Bigger digger (talk) 21:12, 21 May 2009 (UTC)
Bigger digger, thank you for your input! I think you outlined what I was trying to explain the whole time perfectly. You fleshed it out much better than I. Also, that diff is very interesting; I hadn't realized that the text was manipulated. Wizard191 (talk) 21:49, 21 May 2009 (UTC)
I think "manipulated" is a bit strong, we're all trying to build the web, but it seems that Greg Bard was trying a bit too hard to force the link into areas it didn't quite fit. Greg, the article I linked suggests you should be able to get to TTT from the Main Page, which suggests a different way of thinking about linking that might build the web around TTT. A search in wp suggests Bias ratio (finance) might have a section where TTT is relevant, and there must be social science articles where this phenomenon occurs, but possibly needs clarity, or dare I say, a See also?! Bigger digger (talk) 23:35, 21 May 2009 (UTC)

Should hollow dies be introduced into the lead?[edit]

I don't think so. To me there's plenty more important things that could (but for brevity purposes shouldn't be) be listed in the introduction such as the different types of extrusion processes (direct, indirect, hydrostatic). Wizard191 (talk) 01:19, 28 October 2009 (UTC)

Aluminum extrusion is surprisingly cheap![edit]

This is WP:original research, so isn't suitable for the main article unless someone wants to find references, but I was looking into this for work, and found that the setup cost for a hollow aluminum shape with a 4 inch circumscribing circle was $1200. With a minimum 200 lb lot charge of $800, the total was $2000 + tax. Non-hollow shapes are cheaper.

The "generic" material is 6063 alloy, T5 heat treated. Stronger 6061 is also common, but increases die cost and wear. Of course, lots of other alloys can be used. Almost-pure 1100 aluminum is soft and forms very well.

Production costs start at $4.00/lb (at 200 lb) and go down quite rapidly to $2.50/lb (at 1000 lb) with increasing quantities. Aluminum is 2.7 kg/L, or 1.2 lb/in²/ft.

When considering the difficulty of an extrusion, remember that long thin parts of the die, corresponding to deep narrow grooves in the extrusion, are fragile and hard to support. A long thin aluminum fin is easy to make; it's two in close proximity that is hard.

A screw channel in the extrusion (called a "screw boss" in the industry) is typically 5/6 complete and 1/6 open, and the larger the screw, the easier it is to make. (E.g. #8 screws are preferable to #6.)

Another thing that is difficult is thin walls. Generally, 1 mm is the absolute minimum, and 1.5 mm the practical minimum.

The most important difficulty metric is the so-called "factor", the ratio of the perimeter of the shape (including interior surfaces, for hollow extrusions) to the diameter of the circumscribing circle. Obviously, the minimum possible is π, for a round rod. Generally, a factor below 20 is easy to make, 35–40 is difficult, and greater than 50, although still possible, is challenging. ("55 is a pain in the ass.")

Within these limits, the die cost does not depend on the complexity of the shape. An elaborately curved or ridged shape is the same cost as a simple rod. (Features below 1 mm in size are quite possible, as long as their aspect ratio is limited.)

Remember that die is usually cut slightly undersized, so the first parts made are somewhat thinner; as it wears the thickness of the parts increases. Typically, it might be 0.05 mm undersized on all sides (0.1 mm thinner than designed) initially, growing to 0.05 mm oversized before the die is replaced.

In the aluminum extrusion business, standard custom is that the extruder keeps the die (they are specific to a particular brand of extrusion press, anyway), but is responsible for replacing it if necessary.

Useful references:

  • Sanderson, James (17 August 2000). Hoffman, Jean M., ed. "Smart ways to design with Aluminum Extrusions". Machine Design. Retrieved 2015-09-02.
  • (particularly the "Designing with aluminum extrusions" and "Standard dimensional tolerances" articles.)
  • (reference on costs) (talk) 20:31, 12 March 2010 (UTC)

Aluminium Solar Panels Profiles[edit]

Aluminium solar Panels are widely use in Solar PV Modules —Preceding unsigned comment added by Manishgade3 (talkcontribs) 12:38, 18 August 2010 (UTC)

Picture description[edit]

Current text is: "A horizontal hydraulic press for hot aluminum extrusion (loose dies and scrap visible in foreground)"

But what is seen are not loose dies, but die holders (rings) and bolsters (support tooling). A loose die would be placed in the rings and backed up with bolsters. — Preceding unsigned comment added by (talk) 12:46, 18 September 2013 (UTC)

Tomqim (talk) 12:40, 13 December 2013 (UTC) The extrusion machine that is now shown on the page is NOT an extrusion press, but a billet heater. We can provide pictures of a nice aluminium extrusion press, it is our business (see ). Tom de Meijer Tomqim (talk) 12:40, 13 December 2013 (UTC)

CC BY-SA 3.0 licensed aluminum extrusion video[edit]

If anyone wants it for illustration purposes, the Sapa Group created Animation of aluminium extrusion process. (talk) 08:23, 2 September 2015 (UTC)


We currently have "Joseph Bramah patented the first extrusion process for making lead pipe. It involved preheating the metal and then forcing it through a die via a hand-driven plunger." So far, so good. But i'm a bit wary of what follows: "The process was not further developed until 1820 when Thomas Burr constructed the first hydraulic powered press", since Joseph Bramah also invented the hydraulic press, and this Thomas Burr does not have his article here in WP. --Jerome Potts (talk) 22:40, 13 May 2016 (UTC)

Proposed merge with Reactive extrusion[edit]

currently little more than a dictdef, so may be best WP:SPINOUT from the parent. Widefox; talk 00:53, 31 May 2018 (UTC)