Talk:Sand casting

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Requested Move[edit]

Does any have a problem with me moving this article to Sand casting? I just feel as though the title is very awkward, and I've never heard it called that in industry. Plus, google gives 260,000 hits for "sand molded casting", and 2,700,000 hits for "sand casting". --Wizard191 (talk) 12:11, 26 May 2008 (UTC)[reply]

Normal practice is to use the commonly-used term. Here it also avoids the 'incorrect' spelling of the middle word... :o) -- EdJogg (talk) 00:29, 27 May 2008 (UTC)[reply]
I support the move to Sand casting. "Sand molded casting" implies that the article would be about the casted part, and not the process. Also, "Sand casting" is the accepted terminology. Iepeulas (talk) 15:44, 1 June 2008 (UTC)[reply]
I have notified the guy who moved the article from Sand casting to Sand molded casting and invited him to let us know why he prefers the latter title.Iepeulas (talk) 15:59, 1 June 2008 (UTC)[reply]
The guy who moved the article to Sand molded casting had no objections, so I moved the article to Sand casting.Iepeulas (talk) 00:06, 2 June 2008 (UTC)[reply]

Pop Culture References[edit]

The first thing that popped into my mind when I saw this article was a scene in the recent Iron Man movie when the character Tony Stark uses Sand-Casting during his captivity to begin building his Mech Suit. Is this or other instances useful to note on this page to highlight its function? --Epynephrin (talk) 15:27, 18 June 2008 (UTC)[reply]

No, encyclopedia articles are not the place for such trivia. L0b0t (talk) 21:56, 18 June 2008 (UTC)[reply]

Terminology clarification[edit]

The author is incorrect when he says that all binder systems that are not green sand are called, "air set". Air Set is a specific system that uses a furfuryl alcohol binder. The binder is mixed with the sand and when exposed to the air, sets up in a few minutes of time. In a mold or core box, the exposed surface will set first. This makes stripping the mold relatively easy if the surface is not complex or deep. A complex or deep surface may collapse as the box is stripped or you may have to wait an inordinate amount of time for it to cure. Air set has largely been replaced by other binder systems. A big reason for that is that furan is toxic to aquatic life and will quickly require that you file a form R with the EPA if your foundry decides to use it. There are many binder systems, each with it's own strong points. In the industry, what the author calls "air set" is referred to as "chemically bonded sand". That goes for molds and cores. The term "no-bake" is the preferred term if the chemical binder is indeed not baked. That term, no-bake, is because the main binder system used before air set was to mix sand, linseed oil (later MDI), flour, water and clay to produce a mold that was soft when packed into the boxes, yet relatively strong. It was stripped out soft and then baked to become hard. Those cores and molds were called, "hard core" or "baked" molds. They were still in common use up to the early 90's.

The author speaks of synthetic and bank sand but is really too vague in his explanation to have someone understand the terms. These are green sand classifications. Bank sand / natural bonded sand is sand that already has a clay content which was a result of the natural process that placed that sand, such as a river deposited sand. A good bank sand has between 3 and 5 percent clay. The foundryman only needs to add water and mix. A synthetic sand is sand that does not naturally have a binder in it or from which the binder has been stripped. Synthetic sand may start with lake sand or a sand such as the St. Peters sandstone which is an Ordovician aged sand that is likely a beach sand deposited in salt water. It also encompasses sands that are made of crushed rock, such as olivine or which are benefacted sands. That is to say, sands that have specific minerals in them concentrated to make a product, such as zircon, staurolite or chromite. Graphite sand and ceramic sands are also synthetic sands when they have binders added to them. They are synthetic in that they are not naturally occurring and need other binder materials blended with them to produce a satisfactory green sand. Synthetic sand allows the use of binders like western bentonite clay which does not naturally occur mixed with sand, to be used without other, less strong clay.

The author is obviously not very familiar with green sand when he states that the coarseness of the surface denotes green sand. Green sand that is properly mixed and molded can give a cast metal surface that will shine. On the other hand, chemically bonded sands frequently yield coarse surfaces because the sand needs to be coarse to limit binder consumption and limit gas defects from the burning of the binder. No-bake shops also typically grind up the used chemically bonded sands and blend them with a percentage of new sand to limit consumption of sand. If the sand could only be used once then the cost of sand and disposal would be cost prohibitive. This ground up used sand is typically pretty coarse in nature because the old binder is not removed. Green sand does not need to be crushed after use. The metal drys out the water and the sand collapses. It is reactivated by adding water and mulling. If the sand is fine grained and both properly mixed and molded, green sand competes with plaster in finish.

I don't know when sand molding came into existence but molding machines came into existence long before 1950. I think that you have to define partially-automated. In the 1950's, fully automated molding machines were in existence. 70.88.124.61 (talk) 17:58, 6 April 2010 (UTC)[reply]

"Types_of_molds"[edit]

The distinction in the types of molds is confusing and incomplete (it doesn't mention expandable and non-expandable molds), see Talk:Casting#Article_arrangement

In addition, the fact that only Cold Box is mentioned is also weird, allot more types exist; a table that can be integrated to the article:

Resin, procedure, trade name[1] Curing Curing temperature Curing reaction time Model production Core production Alloys Batch size
Furan resins self-hardening 10 to 30°C 10 to 120 min medium to large sometimes ferrous small to large
Phenol resins self-hardening 10 to 30°C 10 to 30 min large no ferrous small to large
Polyurethane resins ("Pepset", "Pentex") self-hardening 10 to 30°C 5 to 60 min small to large sometimes ferrous + non-ferrous small to large
Phenolic resins ("Alfaset") self-hardening 10 to 30°C 5 to 400 min small to large sometimes ferrous + non-ferrous small to large
Alkyd resins self-hardening 10 to 30°C 50 min large sometimes steel small
Silicate resins self-hardening 10 to 30°C 1 to 60 min small to large no ferrous small to large
Phenolic/Furan resins ("Hardox") Gas-hardening 10 to 30°C immediate small yes ferrous + non-ferrous all
Polyurethane resins ("Cold Box") Gas-hardening 10 to 30°C immediate small yes ferrous + non-ferrous all
Phenolic resins ("Betaset") Gas-hardening 10 to 30°C immediate small yes ferrous + non-ferrous all
Acryl/Epoxy resins ("Isoset") Gas-hardening 10 to 30°C immediate no yes ferrous + non-ferrous all
Silicate resins Gas-hardening 10 to 30°C immediate small yes ferrous + non-ferrous all
Oil (linseed, fish oil) Thermohardening 180 to 240°C immediate small yes steel small
"Warm box" Thermohardening 150 to 220°C 20 to 60 sec rarely yes ferrous medium to large
"Hot box" Thermohardening 220 to 250°C 20 to 60 sec rarely yes ferrous medium to large
"Croning" Thermohardening 250 to 270°C 120 to 180 sec yes yes ferrous + non-ferrous large

In addition, as mentioned at the other article's talk page (Casting), there would be a distinction of "green sand" and "sand + resin"; an important thing that should be included in the article would be the losses in sand. Typically, "green sand" can be fully regenerated (reused via special procedure, will upload image of this), sand with resin can not be fully regenerated, losses are 10 to 60%, additional recuperation (reuse via another special procedure, not the same as regeneration) can reduce the losses even more.

Also mention that the amount of resin used with sand is 1 to 3% —Preceding unsigned comment added by 91.182.226.145 (talk) 10:26, 13 December 2010 (UTC)[reply]

91.182.74.122 (talk) 15:25, 11 December 2010 (UTC)[reply]

I agree that there are plenty of sand types/mold types missing and I like the table you put together, but what's it based off of? Please provide a ref. Also, what is "Model production"? Wizard191 (talk) 17:26, 11 December 2010 (UTC)[reply]
I added the book reference in the table. As I understand it "Model production" is probably the size of the piece that is casted, I translated it from "Vormproductie", where "vorm" can either mean "shape" or "mold"; the size of the piece is the only thing not yet in the table so that would make sense; however I'm not 100% sure since at the last 3, the input reads "rarely", and "yes", I guess though that my literally translation will allow others to understand it, since I'm not an expert in sand casting, but others with more knowledge on it can probably make sense of it. If it doesn't though, we can leave out the column.

91.182.102.126 (talk) 11:00, 12 December 2010 (UTC)[reply]

I'm pretty sure it means "mold", because that would jive well with the next column "core production". So it means is the process used to produce a mold or a core or both. Wizard191 (talk) 19:39, 12 December 2010 (UTC)[reply]
Added first of 2 images:
Green sand regeneration cycle

91.182.102.126 (talk) 10:29, 12 December 2010 (UTC)[reply]

  • In an article on sand casting, I'm against going any more specific than unbound sand (historical, and lost foam), green sand, oil-bound sand (i.e. easily reusable) and resin-bound sand (i.e. one-use resins). There are a great many resin binders, but they're not of interest to readers of their very first general-level encyclopedic article on sand casting. Brand names are unimportant at this level, as are the differences between furans, PU and phenolic resins. I can't even see the value of the further columns in that table. Possibly one that distinguished between ferrous, cuprous and light alloys, should such a distinction be easily drawn between the broad binder groups we're discussing (I suspect it isn't).
The purpose of this article is to take a lay reader and give them an understanding of "sand casting". No more than this, certainly not to throw over-specific manufacturer's data at them and have none of it stick. Andy Dingley (talk) 17:25, 13 December 2010 (UTC)[reply]
I agree that the brand name ones ought to be thrown out. That's getting too specific for the article. Wizard191 (talk) 01:43, 14 December 2010 (UTC)[reply]
I don't think that removing the brand names are a good idea; ie most articles still have to appear and there is a good chance that they could be created using the brand name. Hence, although I am also not a fan of brands/commerce, the names will certainly have their value in building out the articles regarding the resin types; after this has been completely done, the brand names could be simply mentioned in the new articles (the articles being renamed to the appropriate chemical resin type). Once things are organised a bit more, we can see whether we can place the other information of the table to more suitable articles, and simply provide a list here, along with the main reason why a specific resin type is chosen in each specific situation.

91.182.242.10 (talk) 08:42, 20 December 2010 (UTC)[reply]

References

  1. ^ Beste beschikbare technieken voor de gieterijen by L.Goovaerts, Y.Veys, P.Meulepas, P.Vercaemst, R.Dijkmans

Merger with Green sand[edit]

I think the two article should be merged, they cover, more or less, the same topic. I don't think I've heard sand called molding sand but I have heard casting sand. Iepeulas 13:01, 5 August 2007 (UTC)[reply]

I have merged the Green Sand into the molding sand category as green sand is a type of molding sand and there isn't enough info to justify two articles.Iepeulas (talk) 00:47, 21 January 2008 (UTC)[reply]

Different pages for each sand type[edit]

I think each type of sand should be listed as a different article and in the molding sand page there may be a little bit info in general about molding sand basics and links to various types of it. Pushkraj.janwadkar (talk) 10:17, 16 June 2009 (UTC)[reply]

Right now there just isn't enough information to warrant separate articles. That's why green sand was merged into this article awhile ago (as you can see in the section above). If, at some point there is enough info to warrant separate articles, it can then be split off. In the mean time I suggest you just create individual sections for each type within this article. Wizard191 (talk) 16:35, 16 June 2009 (UTC)[reply]

Why Does "Silica Sand" Redirect Here?[edit]

It seems as though silica sand should not redirect to one use of the material. As an alternative, why not redirect silica sand to silicon dioxide? Silica redirects to silicon dioxide, but not silica sand.

Vance.scotty (talk) 14:54, 15 May 2014 (UTC)[reply]

Green sand[edit]

The percentages stated regarding the contents of greensand. Is it by weight or volume? Please remove this section when this has been clarified. Thanks

//Marcus — Preceding unsigned comment added by 62.65.125.252 (talk) 10:33, 27 July 2014 (UTC)[reply]

Garbled sentence[edit]

Pattern-makers are able to produce suitable patterns using "according to the percentage of extra length needed). This sentence has become garbled: the quotation marks are opened and not closed and the bracket is closed but not opened. Any idea what it should mean? — Preceding unsigned comment added by 82.27.181.141 (talk) 10:08, 26 May 2017 (UTC)[reply]

A careless edit must have done that. Wait a week, then the sentence can be removed, unless someone wishes to peruse the article history and fix it.--Quisqualis (talk) 22:44, 26 May 2017 (UTC)[reply]
Checked a few revisions, found the previous version of the sentence. The information was rewritten into the preceding and following sentences, but the editor failed to completely remove the sentences they were replacing. With the garbled sentence removed all information is still contained in the paragraph, only without the use of confusing parenthetical sentence structure. If interested, the edit was performed January 10, 2017. Matthias Alexander Jude Shapiro (talk) 18:27, 8 June 2017 (UTC)[reply]