Dural questions

Hi,

I posted a while ago about trying to find some 7075 which I thought at the time is the modern name for Dural. I've since come across some references that say 2024 is Dural, can anyone here tell me which is correct ? I need the better temp range that Dural gives me cf normal high strength alloys.

As a supplementary question can anyone tell me where I can buy model engineering type (ie small) of Dural (whatever the number) ? I really need a place that's known to stock it since all my attempts have ended in failure.

Thanks in advance,

David

Reply to
mangled_us
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Possibly because you are not connected with, or use, a machine shop, you won't know of people like Alloy Sales at Hatfield or similar places throughout the country. There really are plenty of sources of both information and metal, but you need to be in touch with people in the supply chain or have access to data on the metals you require.

Most specialist suppliers will back away from a caller who doesn't really know what he wants, so get boned up on the requirement and be prepared to quote type numbers etc to them, that gets a far better response.

We have good metal contacts through our local guys who do turning and CNC work for us, plus the venerable Reliant Owner's Club Chairman, John S who is the fount of most knowledge that is worth knowing :-))

Peter

-- Peter & Rita Forbes Email: snipped-for-privacy@easynet.co.uk Web:

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Reply to
Peter A Forbes

Smiths metal centres sell 7075, and have details on the web site.

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I think one problem may be that asking for "dural" is almost the equivilent of asking for "steel". There are now so many different aluminium alloys available.

Regards

Kevin

Reply to
Kevin Steele

Both the above are high strength aluminium alloy. (Dural) But you need also to specify the heat treatment you require, I've got the relevant data if you need it. To keep things simple 99% of the alloy sheet used on aircraft would be 2024-T3 alclad. What do you want it for?

I've purchased 2024-T3 alclad before from CSE at Oxford (Kidlington) airport. It's quite expensive because you will be getting a release certificate to provide traceability etc. Where abouts are you located?

Julian.

Reply to
Julian Stafford

You may want to look at

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regards,Mark

Reply to
mark

David, Dural is a generic trade name for aluminium/copper alloy

Different specifications have different numbers. 6061 is practicall pure ali, 2024 is the common or garden variety, and 7075 is a harder more brittle alloy. More important is the temper of the meta designated by a dash number after the spec. -0 is fully soft, -T3 i half hard and will bend around small radius (most common on majority o aircraft and -T6 which will crack when bent. I need to fish out my aircraft engineering notes to be more specific (I've been out of the trade for a few years now.

Possibilities to obtain small amounts are if you have an aircraf maintenance facility nearby see if you can score some bits from thei offcuts bin (behind their metal guillotine), might cost you a couple o packets of choccy bickies for their tea room. Otherwise try a local scrap merchant who collects from such places. Th numbers and thickness are printed on the sheet. Heat treatment is a whole different ball game which I wouldn't want t generalise on without my notes, even though I used to be in charge of heat treatment salt bath doing ali stuff, it was about 25 years ago Suffice to say, at this stage, that pressed ribs etc, are formed out o ) and then heat treated to T3 to give strength. Hope this helps your understanding a bit, let's know if you need mor gen and I'll see what I can find. Neville.

L.A.M.E. (NZ) # 164

-- Kiw

----------------------------------------------------------------------- Kiwi's Profile:

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Reply to
Kiwi

Well, as I said I want 2024 'cos I need the temperature range (application is model IC engine cylinder heads). Alloy Sales don't list 2024 but thanks for the useful pointer anyway.

David

Reply to
mangled_us

Hi,

I won't need Alclad because I'm going to machine it all over anyway. I forgot to say in my original post that I need the temperature range of

2024 because my application is model IC engine cylinder heads. I need a machineable temper (T6 ?). And the address of someone who stocks this stuff ! :-)

Thanks,

David

Reply to
mangled_us

In that case try

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who sell aluminium in small quantities. They do HE15 and HE30, but as they specialise in parts for model IC engines it is likely to be ideal for your application. You can get spark plugs, coils, etc from them as well.

Regards

Kevin

O. I

Reply to
Kevin Steele

Metal Supermarkets have never let me down.

Reply to
Sandy Morton

The usual alloy for cylinder heads is LM25 which has about 7% silicon. LM13 is the usual alloy for pistons which are a much more demanding application and has between 10% and 13% silicon. It would be more than satisfactory for heads and machines nicely after heat treatment. Why don't you contact some foundries, see if they cast either of those, most do LM25 anyway, and get them to pour you a couple of slabs and have them heat treated in with another batch. The cost would be minimal compared to forged material. You could pour them into a biscuit tin or similar without problem. It may even be that a normal Alcan casting brick of the stuff would be the right size for you and probably only a quid or so a kilo.

Someone on here has a home foundry (whoever it was that was advertising a spectrometer recently) and I have plenty of scrap heads and pistons for you to play with if you want them. I get 50p a kilo for them and you would be welcome to as much as you want for that. There's about 200 kilos of the stuff in the scrap store at the moment waiting to be taken to the recyclers.

In fact any foundry could melt them down and pour them into a tin for you. Some schools and colleges also have little foundries which would do the job for free probably as an exercise for the students. Heat treatment costs pennies if you can wait for a similar batch. There is also a company called HIP who can take a casting and treat it at high pressure and temperature to remove porosities and improve strength. In effect they turn a casting into a forging. Google will no doubt find them.

-- Dave Baker

Reply to
Dave Baker

Can I remind you of that if I ever get my furnace working????

Mark Rand RTFM

Reply to
Mark Rand

In message , mangled snipped-for-privacy@yahoo.com writes

From experience of model IC engines I can tell you 6082-T6 (Good old HE30) is good enough for Model Cylinder heads.

7075 makes a good strong conrod.

Piston materials are harder to get. I have stocks of Mahle 138 for smaller pistons. It's quite hard to get these days. I got enough for a few hundred pistons yet ;-)

For larger piston 2618A works well. Wilsons PLC can supply it.

Wayne....

Reply to
Wayne Weedon

Hi,

I can wholly recommend Metalfast in Swindon

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They'll pretty much get any grade you want.... and cut it to your required sizes. I've often bought 6" lengths at reasonable prices.

In answer to the question on Ali grades, the following may help:

6082-T6 - good general purpose material (same as HE30 if I remember correctly) 7075-T6 - high tensile strength alloy, low ductility. Machines beautifully, especially with carbide tips and coolant. 2014-T6 - almost as strong as 7075, but more ductile. 2024-T3 (or T351) - I think this is what you're after, since it is more stable at high temps than other alloys. I've used it with success for brake disc mounting bells on a racing car, where they get damned hot!!!

Hope this helps

Alastair

Reply to
Alastair

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