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[Reade Models]

Funny, I never knew that the Ancient Egyptians were into injection moulding?

(Or was that just the local government ones)?

 

Malc

[Davew]

Hi
Sheerline  that is why fishermen do not use lead weight's any more.
DaveW

[sheerline]

And all made of lead Colin.... Er... I wonder what that model had for ballast? Pound to a penny it's a tad top heavy!!!!

[Colin Bishop]

It's a display model, it's in a glass case! Clever chaps these Egyptians, very skilled. They learned it at their Mummy's knee. 

[sheerline]

Davew, exactly what material are fishermens weights made out of these days?

[Colin H]

Don't know much about white metal fittings but very well up on UK lead regs.

Lead is banned in two types of solder one is used in the production of electrical products and the other is for use on `potable` water supplies i.e. drinking water.

60/40 solder is still easily available I use it every day at work as I find it runs better than lead free.

As to lead being poisonous well yes it is in certain circumstances but as usual in the UK the authorities have gone over the top. We must use lead free solder for all potable work nowadays, but there are still many thousands of miles of lead water pipe still in everyday use. Every time you see a Victorian terraced house it will still have its lead water pipe. As to lead turning to dust the oldest I have seen is a lead gully supplying water to a pond in Matlock Bath it was installed by the Romans.

Colin H.

[craftysod]

And also lead piping on gas,we get loads of it out everyday,when replacing new connections in peoples houses,funny how people worry about paint,asbestos,but dont check gas meter or shed roofs,there are harmfull contaminates everywhere
Mark

[Colin Bishop]

Doing a bit of digging on the problems with disintegrating pre war cast metal toys brought up this link on zinc pest. which i think may be relevant to the discussions on this topic. http://en.wikipedia.org/wiki/Zinc_pest
There are also several other links if you Google Zinc Pest.

There is also something called Tin Pest which affects lead free solders.

Colin

[Pat Matthews]

Yes I agree, the turn-to-dust concern is of limited applicability!
Again, the article above is good reading, but the digest goes something like:

Some stuff gives off acetic acid (mainly woods, also some paints...).
Acetic acid and CO2 (oh no!) are at the root of lead rot/cancer/pox, which indeed turns lead to dust.
But- one needs to have virtually no ventilation for the reaction to have a go... hence the concern for historical museum models.

So, I won't eat my lead filings, and painted or otherwise my lead (?) fittings won't be cooped up in a glass display case... so I guess my only concerns should be top hamper and tool fouling, both of which can be dealt with- the latter by methods already given, the former by-- MORE LEAD!

Pat

pps: I don't own a gun, but I do have a good bit of lead shot. I do buy British (and Danish and German) models, because they're the best. And apologize for ASKING if lead is legal???

[andygh]

Sheerline  that is why fishermen do not use lead weight's any more.

Wrong I'm afraid  , see link

http://www.environment-agency.gov.uk/subjects/fish/246986/255175/257210/?version=1&lang=_e

Davew, exactly what material are fishermens weights made out of these days?

Lead  , see above


Anyhow, what's the problem with lead, I've been wielding a soldering iron for years and I'm perfectly fine.......................... wibble

[Bunkerbarge]

I think just to remind ourselves of the original post the concerns with machining, cutting or dressing up white metal fittings gives exactly the same cause for concern whether they be from any one of the many british manufacturers or any other world wide producer of model boats that use cast white metal in thier construction.

As you rightly say your drill bits and files get clogged up, that is a normal consequence of cutting such material and can be prevented, or at least controlled, by taking one or two precautions.  As Bluebird has rightly pointed out using a slow cutting speed and a lubricant will both help but it is also cruicial that you use sharp tools.  For twist drills you could even look up what the appropriate included angle should be for the chisel cutting edge, which are usually factory produced for mild steel at 118 degrees, but for a softer metal you would be looking at a steeper included point angle and possibly a higher cutting face angle.  Bearing in mind though that sharpening a drill bit is beyond all but the most skilled engineers trying to adjust this would be a bit of a waste of time.

I think mentioning a particular manufacturer has not been particularly constructive when a great number of them use exactly the same material in the manufacture of thier kits and so we are faced with the same issues with all of them.

Lets also remember why this metal is used.  An average price for a 4-5 foot long model using fibre glass hull, wooden construction and white metal fittings is usually in the region of £3-500.00.  A similar size model using a fibre glass hull with wooden construction and turned brass fittings tend to be in the region of £1500.00, which puts them beyond the range of a high percentage of modellers.

White metal fittings in model kits are definately with us to stay whether they contain a percentage of lead or otherwise so it is really up to us to decide whether we want to use such fittings or find an alternative. 

[Admhawk]

Lot's of interesting things in this thread. Here's a little more.

This article from the curator of the US Navy explains the lead corrosion process pretty well, as Pat mentioned, it is Acetic acid mainly from wood bases that create the environment within a closed display case to cause the lead to rot. It's a self sustaining process and doesn't take long once the conditions have been set up.

http://www.dt.navy.mil/cnsm/lead_01.html

Where I work we use lead a lot for shielding from Radiation. As Bunkerbarge mentions, it's the machining and forming of the material that is the problem. Whenever it is cut or filed or heated/melted it releases small particles into the air that can be inhaled/ingested. Anytime we use or touch lead, we wear gloves and a mask. If not practical or possible, we have good ventilation and wash our hands immediately afterwards.

Lead shot is still available in NA, but banned from use on ducks because of the effects on the wet lands. Lead fishing weights are still available. Most white metal is a composition of antimony, tin, lead, cadmium, bismuth, and zinc. Composition is changed for desired characteristics, ie ease of casting, melting point etc. There are many tin and pewter based lead free alloys sold today that are used in toy casting.

And the last thing I'd like to mention, I understand Pats desire for knowledge, but as a manufacturer, I prefer questions about my product aimed toward me. That way I can answer and avoid public speculation that can lead to misguided theories about the items I sell. Fighting peoples incorrect impressions about a product is very difficult and those theories become 'fact' as far as people are concerned, because someone said it in a forum without thinking. It can put a huge dent in sales and in some small companies cause enough financial hardship making it difficult for manufacturers to stay in business. I've seen it happen.

'Nuff said by me, have fun sailing!

[andygh]

Lead shot is banned from use over wetlands in the UK also 

[PT Sideshow]

Having come late to this discussion, The first problem is terms that are used in the hobby and by people working with the alloys that are cast.

White metals that are gray with low melting points are composed of assorted  percentages of:
Lead Pb, Tin Sn, Bismuth Bi, Cadmium Cd, Antimony Sb, the other metal used in the alloys is Copper Cu,
The generic names of white metal, pot metal, and type metal and wheel weights. Are given to low fusing alloys( also used to described them) Which have melting points below 350'F or 145'C(not exact).

The fumes that are produced from the above are hazardous and require a fume hood when casting. As a side note coming from a jewelry background. If any of the above is heated higher than its melting point. They will burn into and ruin the following. gold,platinum.silver brass,copper and bronze.

All work and tools must be separate from those used for other metals. Pewter and Britannia metal are often included in the above group even though they should not be.

When the laws changed way back in England of old in regards to Pewter the safe alloy is:
Britannia metal }Copper Cu 2%,Tin Sn 91%,Antimony Sb 7% Melting point 295'C 563'F

Pewter } Copper Cu 6.8%, Tin Sn 85%, Antimony Sb 1.7%, Bismuth Bi 6% melting point 260'C 500'F

Slight disclaimer( so this doesn't turn it to your off by a degree or 2
Now if you pick up 10 books on the subject of casting you will generally be given 10 slightly different temperatures. You can use your favorite, and the percentages of content are by weight.






One of the old standbys that have been replaced by a host of new low temp alloys that are used in hobbies and industries

Cerrolow-117
Melting point is 117° F. Composition is 44.7% Bismuth, 22.6% Lead, 8.3% Tin, 5.3% Cadmium, 19.1% Indium.
   
Cerrolow-136
Melting point is 136° F. Composition is 49% Bismuth, 18% Lead, 12% Tin, 21% Indium.
   
Cerrolow-140
Melting point is 134° to 149° F. Cerrolow-140 has no definite melting point. Composition is 47.5% Bismuth, 25.4% Lead, 12.6% Tin, 9.5% Cadmium, 5% Indium.
Cerrolow-147
Melting point is 142° to 149° F. Cerrolow-147 has no definite melting point. Composition is 48% Bismuth, 25.6% Lead, 12.8% Tin, 9.6% Cadmium, 4% Indium.
   
Cerrobase
Melting point is 255° F. Composition is 55.5% Bismuth, 44.5% Lead.
   
Cerrobend
Melting point is 158° F. Composition is 50% Bismuth, 26.7% Lead, 13.3% Tin, 10% Cadmium.
Cerrocast
Melting point is from 281° to 338° F. Cerrocast has no definite melting point. Composition is 40% Bismuth, 60% Tin.
   
Cerrosafe
Melting point is 160° to 190° F. Cerrosafe has no definite melting point. Composition is 42.5% Bismuth, 37.7% Lead, 11.3% Tin, 8.5% Cadmium.
   
Cerroseal
Melting point is 240° to 260° F. Cerroseal has no definite melting point. Composition is 50% Tin, 50% Indium.
Cerroshield
Melting point is 203° F. Composition is 52.5% Bismuth, 32% Lead, 15.5% Tin.
   
Cerrotru
Melting point is 281° F. Composition is 58% Bismuth, 42% Tin.


It isn't cheap for the Cerrolow-117 is $115.20 per 1/2 pound slug

Cerro Alloys 158' F $42.99 Each 1 1/2 pound

Cerroseal is over $500. for 1 1/2 pound of wire 109 feet long has a melting point around 240'Fto 260'F

So the material can be a very very hard item to figure out what it really is.


http://www.miniaturemolds.com/ Here is a US supplier of molds and casting in metal rubber and plastic materials and they do do foreign shipments but You will have to check out the web site




Almost forgot the 30/70 60/40 50/50 etc is the tin/lead percentages in the alloys of the solder which will control the melting temperature.

As with the last pictures you can see it would be almost impossible to tell what alloy or even if it is pewter or lead free alloy with out some info from the manufacturer.

Hope this will aid in the understanding of the alloys used in the hobby world currently

And to the question of files etc. It is a good idea to have only files and trimming tools that are used for only the softer low temp metals no matter what they are.
Once the file is cleaned if you use chalk dust on the file teeth it will help in keeping the metal from sticking to the file. Yep plain old writing on the slate boards or sidewalks chalk. Color doesn't matter