MadModder
The Shop => Metal Stuff => Topic started by: appletree on February 09, 2019, 04:26:42 PM
-
Has anybody found sash window weight a useful source of Cast Iron? Or are they too varied with hard spots to be usable?
I have just been given a dozen
Phil
-
They make great weights for bottom fishing off shore, Seriously, they seem to drop to the bottom faster and I would be reeling up fish while others on the boat were still peeling out line, less tangles for me as well.
-
I brought four home from work, two smaller and two larger. There wan't a whole lot of difference between the sizes I think the larger ones were maybe 30% bigger but the two small ones were unmachinable and the two larger machined quite nicely. I've made quite a few bits and bobs from them.
Bottom line - it's a lottery. Depends on how quickly they were chilled I guess.
-
I do not have a lot of experience in these things, but i do have some that came from a Very old house. One or two that are 4 feet long most round but again three or four that are square. All machine very well and not come across any hard spots ...YET!
Lyn.
-
You can always soften them again, heat to white hot and cool slowly.
Here's a large square one glowing nicely in my 100 kw induction furnace when I had it set up back in 2007
(just had to manually ramp down the power setting so it cooled slowly rather like you would with a pottery kiln to avoid cracking, which was easy as it's a big knob on the control panel!)
-
Thanks for the replies, looks like they are worth having, I guess pre cut lengths could be put on the coal fire in the lounge to soften. Don’t know what it is love must have come in with the coal.
Don’t know what might happen to the carbon content?
Phil
-
I have three about 18 inches long that I turned round. Two looked good. The other one has some holes and pits. I have made model piston rings from one of the good ones and they worked well. Some will be good and some will be bad.
-
White heat? Uhhhh, nope, that's re-melting it. CI melts at 2200F.
For most gray irons, a ferritizing annealing temperature between 700 and 760°C (1300 and 1400°F) is recommended. If you're going by color that's dark red (see below).
You also don't have to keep it in a ramped powered furnace for cool down. just bury the piece in a bucket of wood ashes to cool slowly. In fact you can also do the heating to annealing temps in a wood fire in the brightly glowing embers with a little draft.
Color Temperature [°C] Temperature [°F]
From To From To
Black red 426 593 799 1100
Very dark red 594 704 1100 1299
Dark red 705 814 1300 1497
Cherry red 815 870 1498 1598
Light cherry red 871 981 1599 1798
Orange 982 1092 1799 1998
Yellow 1093 1258 1999 2296
Yellow white 1259 1314 2297 2397
White 1315+ 2397+
-
just a tip with the weights leve them out to go rusty then machine them up in to bar stock then cote them in oil I have made lots of things out of the ones I have
-
I once bought a couple of flat irons in order to use the cast iron. They turned out to be a dissapointmant, not only were they chilled and had the handles cast into them, they also had a number of voids in the castings. I'll not bother again.