normalising BMS

[Garry Coles]

:)Hi everyone
My question tonight is about heat treatment for BMS flat.
The books tell me that you should heat up to bright red, about 800 C, and then let it cool down at room temp. But how long do you keep it at this temp before letting it cool.

Also, is there a web site that gives a list of all the different types of loctite, ( or any other brand that are cheaper ) and what they are all used for. I've tried the loctite site but am unable to get into it

Cheers
Garry in sunny Jersey.

[SteveW]

Garry,

Don't know much about loctite but normalising a bit of BMS is just question of getting it properly red hot and leaving it to cool somewhere out of a draft. If you want to get all retentive about it wrap it in rock wool to slow down heat loss. If you keep it red hot too long it'll grow more of an oxide layer. You'll end up with the equivalent of a bit of hot rolled steel which is what I tend to opt for if there's a choice.

<GRANNY-SUCK-EGG-MODE-ON> All you're doing actually is removing the stress put in during the cold rolling to size process. This stress is mostly in the surface skin and if you separate one side from the other with a hacksaw cut the differential stress causes it to bend. </GRANNY-SUCK-EGG-MODE-ON>

I've had some success by roughing out what I needed from BMS leaving enough spare to cope with any bending and then normalise that. One time I had to re-straighten it first. Then finish to size. This saves having to cook a large bit of steel to an even red all over and saves a lot of gas.

I've also had some success using a vacuum cleaner blown charcoal fire as a means of heating to red heat a big lump of quarter plate I needed to bend. I just had to be careful not to burn the steel or blow the charcoal fire away. Leaving the metal in the charcoal to cool down can also help slow cooling.

This maybe a successful method for rescuing glass hard iron castings although I've not had to try it yet.

[baggo]

Hi Garry,

Try this link for Loctite - it works for me

www.loctite.com/int_henkel/loctite_uk/index.cfm

John

[Tony K]

Garry, this works for me with the Loctite website ;D....

www.loctite.co.uk/int_henkel/loctite_uk/index.cfm?&pageid=313&layout=2

Regards, Tony in Sunny Northampton

[houstonceng]

Re-normalising.

You can always try the method that I've effectively done. Light up the Bar-B-Q with a goodly load of "coals". Bury the BMS in the "coals" and leave "bar-bee" to burn away to ash and get cold.

This is the equivalent of what I used to do with the old open coal-fire at parent's home before Gas-fired CH took over. The ash tends to protect the BMS from oxidising and also ensures that it cools slowly. Whilst the "coals" are alight, they're "burning up" the oxygen with similar effect.

Andy

[ron]

and you can also do a couple of sirloins while you're at it ;D

Ron

[bobfly]

Waste of time heating BMS then having to m/c it flat to start,better using black mild steel skim four faces then skim one face as the datum face and work from that.

[Alan]

Normalizing is a very inportant process for long thin bits of our work.
I have never found black in anything else than one standard grade. Normalized EN1A can be so nice to machine as against a bit of black and your expensive cutters last so much longer

I like the bar-b-q bit. It gives me an excuse to buy a bigger one.



alan

[chris vine]

Hi, I have found a good way to normalize bms is to put it in the log burning stove, bring the whole lot up to a good red and leave it to burn out over night. The metal sits in a pile of ashes and will take most of the next day to cool. Obviously it depends on the size of section but that was for 5/8" by 1/5".

Chris.

[Shawki Shlemon]

Hi all
Last week I normalized two pieces of bms 10x20 mm x250 mm and machined two coupling rods for Dukedog , worked fine and no warping at all . I heated the metal to red hot while it was on fire bricks and and then covered it with fire bricks and let it cool slowly .A simple task worth doing .

[ilvaporista]

I put the pieces in our open log fire just about 8pm when the fire is at it's brightest and then leave them in overnight and fish them out in the morning.

Obviously we don't have an open fire during the summer but there are plenty of other distractions keeping me out of the workshop apart from the heat.

[havoc]

I'm starting on a new loc, and got a few strips of BMS that I would like to use for it. Now I do have to braze them together.

So, can I just braze them and will that do the normalising at the same time, or is this not safe and should I first normalise and then braze?

[Shawki Shlemon]

Hi
If you are going to heat all the pieces red hot all over when brazing them ,then that may be sufficient.If you are not sure then I suggest normalize first then braze. I would do the second .