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Lew Hartswick
12-27-2017, 05:00 PM
Does anybody know what aluminum alloy roof vallley flashing is made of?
It probably doesn't really matter but I would like to know how high a temp.
to completely anneal it. Want to use it as soft as possible to cushion the knurl
on handles in the lathe chuck while turning the other ends. Don't want to
end up with a puddle of aluminum in the furnace. :-)
Thanks.
...lew...

Georgineer
12-27-2017, 06:29 PM
Not a great deal of science in it, but I was taught to draw a line on the aluminium with a bar of soap, then heat until the soap line turns brown. It has always worked for me.

George

Lew Hartswick
12-27-2017, 06:40 PM
Not a great deal of science in it, but I was taught to draw a line on the aluminium with a bar of soap, then heat until the soap line turns brown. It has always worked for me.

George
:-) Our heat treat oven doesn't have a window. :-) It does have a good thermometer though. :-)
...lew...

Doc Nickel
12-27-2017, 06:48 PM
The classic trick for guys using sheet aluminum to form bodywork is to use an acetylene-rich torch flame to coat the part with soot, then reset the torch to a neutral flame and carefully heat the part 'til the soot is burned off.

Doc.

adatesman
12-27-2017, 08:40 PM
If the handles are steel, you're probably worrying over nothing; the aluminum will be much, much softer.

754
12-27-2017, 08:58 PM
Yeah just scribble around on it with soap......heat till Brown or black, cool off.
i use Vice grips or pliers and a propane torch. .works great.

fixerdave
12-27-2017, 09:10 PM
:-) Our heat treat oven doesn't have a window. :-) It does have a good thermometer though. :-)
...lew...

Maybe the temp where carbon starts to burn? 300C

I was taught, hot enough when wood starts to scorch then quench and you get 20min or so of very nice flex. Saved me a few dirtbike levers, until I learned to keep them loose enough to move when things didn't go as planned.

Don't think that's going to help in your application though.

David...

QSIMDO
12-27-2017, 10:35 PM
Sharpie marks.
Hell of a lot cleaner than acetylene smoke and no floaters.
Just heat 'til they disappear.

Lew Hartswick
12-27-2017, 10:43 PM
If the handles are steel, you're probably worrying over nothing; the aluminum will be much, much softer.
No they are knurled 6061 T6 . Projects at school for the kids. It's a lot easier to do if the knurling is done before the other end is turned down. We have done this before but the material we used is all gone now. Even steel knurled will show the chuck jaws marks if held sufficiently to do any serious turning. The handbook has 1220 F as melting point so I wonder how close I dare get to that. I guess I'll try about 800 or so and see.
I'm not going to mess with acetylene soot or soap and torches with a heat treat oven. I just thought someone may have already done this.
...lew...

BCRider
12-27-2017, 10:45 PM
The classic trick for guys using sheet aluminum to form bodywork is to use an acetylene-rich torch flame to coat the part with soot, then reset the torch to a neutral flame and carefully heat the part 'til the soot is burned off.

Doc.

I was told that same trick by an aircraft metal beater. If it's good enough for aircraft.....

Used it a couple of times to anneal and beat back a clutch lever after a dump on the bikes. Never got the urge to try it on any brake levers but it saved me a bunch of money on clutch levers and they were fine. One I straightened and bent again then straightened again and I'm still using it and it's been fine.

Erich
12-27-2017, 11:58 PM
Here you go.

http://lmgtfy.com/?q=aluminum+annealing+temperature

754
12-28-2017, 12:03 AM
Why use acetylene when you can use propane..

adatesman
12-28-2017, 12:28 AM
No they are knurled 6061 T6 . Projects at school for the kids. It's a lot easier to do if the knurling is done before the other end is turned down. We have done this before but the material we used is all gone now. Even steel knurled will show the chuck jaws marks if held sufficiently to do any serious turning. The handbook has 1220 F as melting point so I wonder how close I dare get to that. I guess I'll try about 800 or so and see.
I'm not going to mess with acetylene soot or soap and torches with a heat treat oven. I just thought someone may have already done this.
...lew...


Sounds like you have your process out of kilter then, if you're chucking on a knurled diameter for a subsequent operation.

YMMV

Beazld
12-28-2017, 07:52 AM
I have bought Al flashing at Lowes before. Be careful as some brands have a coating like plastic or some kind of clear paint on it.

Lew Hartswick
12-28-2017, 09:42 AM
I have bought Al flashing at Lowes before. Be careful as some brands have a coating like plastic or some kind of clear paint on it.
WOW I'll check that. That is where I got it. Wonder what will happen to that coating when it get up to temp. :-) Make a mess for sure.
...lew...

Toolguy
12-28-2017, 10:34 AM
You don't want to breathe the fumes for sure.

wombat2go
12-28-2017, 11:26 AM
Roofing and guttering might be of 3003 Alloy which is strain hardened ( Hxx)
It is described here, including a softening heat treat.
method at the bottom left of this page:
http://www.atlassteels.com.au/documents/Atlas_Aluminium_datasheet_3003_rev_Oct_2013.pdf

Roofing material might be coated with PVDF - polyvinylidene fluoride.
Here is an msds:
http://www.westlakeplastics.com/msds/msds_kynar%20740.pdf

I would suggest using bare Al sheet if you are going to heat it.

754
12-28-2017, 01:00 PM
If it's being formed its probably 3003 or 5000 series.
It would take longer to warm the oven than to use a propane torch and soap.
Some heat guns don't read properly, i rather use soap. I have done 1/8 with propane.

To test your process cut strips about 1 to 1.5 wide by 4 inch, you will know if it annealed by bending by hand..

Dan Dubeau
12-28-2017, 01:16 PM
What about alternative methods to hold onto the knurling. Plastic pipe jaw protectors, or maybe get the kids to 3d print some jaw protectors if you have access to one.

754
12-28-2017, 01:24 PM
I use thick non corrugated cardboard.

reggie_obe
12-28-2017, 01:47 PM
What about alternative methods to hold onto the knurling. Plastic pipe jaw protectors, or maybe get the kids to 3d print some jaw protectors if you have access to one.


I use thick non corrugated cardboard.

Cardstock, small strip of emery paper, strip of Al. cut from a beverage can, etc.

EddyCurr
12-28-2017, 04:47 PM
Our heat treat oven doesn't have a window, it does have a good thermometer though. I'm not going to mess with acetylene soot or soap and torches with a heat treat oven.
You probably know that Tempil offers inexpensive temperature-indicating sticks and 'paints'. Tempilaq liquid/paint is perhaps the better choice for an oven.


http://www.tempil.com/temperature-indicators/


The handbook has 1220 F as melting point so I wonder how close I dare get to that. I guess I'll try about 800 or so and see.

For 1100 and 5052, the annealing temperature is 650F. For 3003, the temp needs to be taken to 775F.

Best determine what alloy you have first, or start w/ 650F and check the results.

EddyCurr
12-28-2017, 04:57 PM
Why use acetylene when you can use propane..

Acetylene deposits the tell-tale soot that serves both to indicate that the desired area has been prepped and then that it has been heated just enough, reducing prospects of melting/burning through the parent metal.

754
12-28-2017, 08:58 PM
I don't have to pay rental on soap bottles, nd it has no soot..

Lew Hartswick
12-28-2017, 10:17 PM
OK folks thanks for all the ideas. First off I'm not doing a piece or two It'll be half a doz sheets of 12 x 12 to be later cut into pieces about 2 x 3 ; second on the doing it in reverse orientation, the other end is turned to .375 and threaded . To hold by that part sufficiently hard to do the knurling leaves unacceptable marking on the part. ;third I may give the cardboard a try. Lots of good heavy "cereal box" cardboard around. I'm concerned about the torsional characteristics of that though. ; Plastic jaws , I've tried before (made with PVC pipe split) wasn't very uniform in thickness so made for terrible runout. ; My only concern now is if there is a plastic coating on the stuff I got at Lowes. May have to look further. In any event it does appear that temps of 500 deg F or so will be adequate to anneal about any thin sheet aluminum I find.
When school starts again in Jan I'll give all these things a try and if any surprises show up will report them. :-)
Oh I forgot, The "soda can" mentioned, We have tried that, it's so thin and HARD it may as well be not there. If it were to be annealed it may as well be kitchen foil wrap. :-)
...lew...

bobw53
12-29-2017, 07:22 AM
Not to rain on the fun, but 3003 sheet is almost free and then you don't have to worry about anything.

1x4ft of .030" thick is under $10 at online metals.

This is some .030 thick 3003 H14 that I make some parts out of occasionally... That was done by hand, no annealing, straight out of the box.

https://c2.staticflickr.com/2/1679/26751977045_18496b72ce_c.jpg

EddyCurr
12-29-2017, 02:21 PM
This is some .030 thick 3003 H14 that I make some parts out of occasionally... That was done by hand, no annealing, straight out of the box.

https://c2.staticflickr.com/2/1679/26751977045_18496b72ce_c.jpgThe following probably doesn't figure much into Mr Hartswick's application (soft jaws), but it might be a factor for people with other uses.

While 3003 aluminum does not respond to heat treatment, cold-working 3003 DOES increase its hardness.

As demonstrated, bobw can easily tie ribbons of as-rolled 3003 in neat bows. Once.

But having cold worked the material, it will have hardened. Unless it is annealed back to the initial soft condition first, then further cold working will be more difficult and there will be an increased likelihood that cracks form in the material when worked or sometime afterward.

As mentioned earlier, cold work hardening probably isn't an issue for the OP's intended application, but this could be for others. Annealing really isn't a very difficult procedure and it doesn't require a big investment in equipment.

Steve_Cole
12-29-2017, 04:12 PM
Why not use some strips of lead flashing?

Sent from my Nexus 6 using Tapatalk

Lew Hartswick
12-29-2017, 10:46 PM
Why not use some strips of lead flashing?

Sent from my Nexus 6 using Tapatalk
You have to be kidding. :-) with the current phobia about anything with even a bit of lead in it, where would anyone get thin sheet lead? Not to mention what it would cost if available. :-)
...lew...

wombat2go
12-29-2017, 11:05 PM
You have to be kidding. :-) with the current phobia about anything with even a bit of lead in it, where would anyone get thin sheet lead? Not to mention what it would cost if available. :-)
...lew...

https://www.amazon.com/Sheet-Lead-64-12-24/dp/B001QV3DCO/ref=sr_1_1?ie=UTF8&qid=1514606624&sr=8-1&keywords=lead+sheet+metal

J Tiers
12-29-2017, 11:58 PM
https://www.mcmaster.com/#lead-stock/=1awjg0e

1-800miner
12-30-2017, 09:47 AM
Lew I think I have what you need.
Soft aluminum strap about one inch wide and a mile long.
I can cut a bunch of strips and mail it.
Can you use inch wide stuff?
I can fill a flat rate box with maybe a fifty foot coil.

Lew Hartswick
12-30-2017, 08:43 PM
Lew I think I have what you need.
Soft aluminum strap about one inch wide and a mile long.
I can cut a bunch of strips and mail it.
Can you use inch wide stuff?
I can fill a flat rate box with maybe a fifty foot coil.Thanks! but No I think I need pieces about 2 x 3 . The 2 for the length of the chuck jaws and the 3 for the circumference and a bit "sticking out" of the 3/4 dia work.
...lew...

boslab
12-30-2017, 09:50 PM
I still use copper pipe, offcuts of 15,22,28 work fine (I know crazy, we use metric tube with BSP fittings, the barmy army in deuchland like metric, BSP really annoys them, BSB confuses them (esp LH!)
I do quite a lot of bricklaying so I use a fair amount of lead (what they call code 4 or 14lbs sq foot I think, about 4 MM)
Most roofs and chimneys use lead tray and flashing in brick, I don't think I know of a builders yard not selling rolls of lead flashing, though Ali is appearing but it's thin rubbish.
Lead is toxic but wearing gloves your not going to poison yourself unless you like chewing on it!
You would probably ingest more lead from your water pipes if there's any lead there.
Mark

Illinoyance
12-31-2017, 02:03 PM
Instead of annealing hard material, why not just buy soft aluminum like 1100. McMaster sells it. The aluminum sold by the big box stores is probably 1100. I use it for padding vise and chuck jaws and for sacrificial parallels under work I clamp to the table. I always have a stick or two of 1/8 x 1/2 in the shop as well as some soft sheet material. The suggestions for using copper pipe are fine, provided you have a ready source of it. A few wraps of solid copper wire also work for padding chuck jaws.

A different approach is to allow extra stock on the end for chucking and cut it of later.