Bent coal grate

copper · Post by **copper** » Mon. Apr. 29, 2019 8:29 am

On my "new" Andes combination range, one of the coal grates has a pretty bad bow in it (say ~1.5 ") – can I heat this red-hot with a torch and GENTLY push it back to straight? Is an oxy-acetylene torch the right tool? Obviously, I would not want to "force it" for fear of breaking the casting. The other grate is mostly straight, so once I fix the one, I am good to go. Just want some info from anyone who has done this to build my confidence...

Sunny Boy · Post by **Sunny Boy** » Mon. Apr. 29, 2019 10:35 am

From what others have told me who have tried, it will break.

Can you use the other grate as a pattern to cast a new grate ? If they are too different for that you can still use the warped one to have a new one cast.

Try contacting Tomahawk foundry. They do a lot of work for us antique stove owners and the stove restoration shops. They deal with warped and damaged grates a lot. They will section the grate to make it straight enough to use it as a pattern to recast a new grate for you. Email Al the owner with pictures and measurements and he'll give you an estimate.

http://www.tomahawkfoundry.com/

I was able to use the long axle coal grate from my range as a casting pattern. Then, after I got my original grate, plus the new grate bars, back from Tomahawk, I just cut off the extra axle length off to make a replacement for the shorter axle warped grate. That range gets run very hot for 9 months of the year and the 3 year old Tomahawk grates still look good as new.

Paul

Post by **franco b** » Mon. Apr. 29, 2019 11:40 am

If heat warped it, then heat can put it back, but that heat has to be applied evenly amd held long enough. Buried in a coal fire big enough, or an oven hot enough. A shim on each end to allow the grate to slump straight. Cooled slowly. Heat from a torch is too localized.

copper · Post by **copper** » Mon. Apr. 29, 2019 4:55 pm

So if I put on a flat surface, shimmed the ends, covered it with coal, started a wood fire on it, maybe added a mild blower and left it to burn I should be good? How long, since I won't be able to monitor the part?

copper · Post by **copper** » Mon. Apr. 29, 2019 5:11 pm

Paul, I will check out tomahawk also. Thx

copper · Post by **copper** » Mon. Apr. 29, 2019 5:15 pm

What would oven temp be to straighten? A little over 2000F and I have a puddle...that would be bad.

Post by **franco b** » Mon. Apr. 29, 2019 5:20 pm

copper wrote: ↑
Mon. Apr. 29, 2019 4:55 pm
So if I put on a flat surface, shimmed the ends, covered it with coal, started a wood fire on it, maybe added a mild blower and left it to burn I should be good? How long, since I won't be able to monitor the part?

The fire would have to be contained by fire brick, floor and sides. You need to get it up to bright red approaching yellow and hold it for fifteen minutes or so. Not easy. Cool naturally slow. Will probably need forced air to get hot enough. Like a blacksmith forge.

Post by **franco b** » Mon. Apr. 29, 2019 5:22 pm

copper wrote: ↑
Mon. Apr. 29, 2019 5:15 pm
What would oven temp be to straighten? A little over 2000F and I have a puddle...that would be bad.

Red hot is about 900 to 1000, so a bit more.

copper · Post by **copper** » Mon. Apr. 29, 2019 11:17 pm

Ok, this could work. I have the fire brick and can rig up a blower. Where do I get a bag of coal in CNY? I can't imagine charcoal bricketts would be hot enough...?

Post by **franco b** » Mon. Apr. 29, 2019 11:40 pm

copper wrote: ↑
Mon. Apr. 29, 2019 11:17 pm
Ok, this could work. I have the fire brick and can rig up a blower. Where do I get a bag of coal in CNY? I can't imagine charcoal bricketts would be hot enough...?

Charcoal was used in the old iron furnaces to melt iron from ore. Blacksmiths tend to prefer a type of soft coal. Lots of air as evenly as possible.

copper · Post by **copper** » Tue. Apr. 30, 2019 9:35 pm

Ok, good point. Won't hurt to try it. Maybe this Sunday...but first I'm gonna ask around for a ceramic kiln. Seems way more controllable.

Sunny Boy · Post by **Sunny Boy** » Wed. May. 01, 2019 9:05 am

There are many coal dealers in CNY now. Where about are you ?

Any of the Tractor Supply Stores - one in Hamilton, one in Norwich, Staelen's Coal Sales in Madison, Top Variety Hardware in Sherburne, Neuman Supply Depot in North Norwich. and more as you go further out from the geographic center.

Paul

copper · Post by **copper** » Wed. May. 01, 2019 10:30 am

Syracuse area, Paul. I will check out TS. Never looked before.

Sunny Boy · Post by **Sunny Boy** » Wed. May. 01, 2019 10:52 am

copper wrote: ↑
Wed. May. 01, 2019 10:30 am
Syracuse area, Paul. I will check out TS. Never looked before.

Try doing a search for "coal sales, Syracuse NY". There are quite a few dealers near by.

And take a look through the pages of Lehigh Matt's listings for all the Lehigh Coal dealers. Lehigh Anthracite Coal Dealers

Paul

stovehospital · Post by **stovehospital** » Fri. Jul. 12, 2019 5:27 pm

Trying to staighten a grate by heating it can be a problem. The grate is bent but it is also stretched. When you bend it back, if you do, the grate will be significantly longer than when you started.
I usually break the grate where it is bent, drill the ends and insert a iron rod. then get the grate back in a straight position and use epoxy to bond things in place. Make sure the grate is the right length and use the repaired one as a pattern. the better the job you do, the less the cost at the foundry. This will work almost every time you need to duplicate a grate.