Bolt problem on antique wood stove

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Frenchman

New Member
Mar 17, 2021
30
France
Hi there!

I have a problem restoring an antique French cast iron wood stove.

As I was derusting it, one of the feet broke loose.

It's the part that was holding it to the body that broke. I guess it's a bolt but I am not sure. The reason I am not sure is specifically because I am having a terrible time removing that "bolt" to replace it.

Here is a video that describes it: https://drive.google.com/file/d/1W3bWWS2-t0wW4a6ypKrNDTJV4izpnf6_

I have applied old gasoline on it and let it react for a day, many days in a row. I have tried turning the "screwhead" with a screwdriver, it won't budge. I have filed the part that is stuck in the stove's body to make it flat and tried to turn it with a clamp, to no avail.

The thing that strikes me is that I don't see any "boundary" between what should be the bolt, and the "hole" in which it is supposed to screw. Neither on the stove's body nor on the foot. It looks blended into the "hole", as if it had been welded. I would be very surprised if it was indeed welded in the past, for 2 reasons. First because I wouldn't see the benefit of doing that. Second because I don't see how on Earth one would have managed to do it with the foot in position.

In the video I have already filed around the "bolt", because I was hoping to remove that little "mountain" around it. I removed most of it all right, but it still looks as if it had been welded.

Would anyone have any idea how I could remove the remnants of this "bolt", without damaging the stove any more? Or an alternative solution to getting the foot back into place?

Thanks a lot in advance for your help!

IMG_9271.JPG IMG_9270.JPG IMG_9267.JPG IMG_9266.JPG IMG_9265.JPG IMG_9264.JPG IMG_9263.JPG
 

clancey

Minister of Fire
Feb 26, 2021
2,060
Colorado
That's a real problem but someone here will know the answer with all the talent we have on this forum and I who knows nothing--wonder about a "blacksmith or someone" like that to take it too...How old is your French antique stove? I wonder about it just breaking off like that and would other areas just break off like that too and it looks maybe welded or a high heat connection with the foot--no screw edges in that bolt--weird but interesting as well...Hope someone has some educated suggestions on how to solve the problem.. mrs clancey
 

begreen

Mooderator
Staff member
Nov 18, 2005
91,422
South Puget Sound, WA
Sometimes it ends up easier to drill it out if the metals are fused together, then retap the hole. That stove base is in bad shape. This could happen again because the leg has lost the backing plate behind it where it attaches to the stove. That puts a lot of stress on the bolt.

Are you fixing this up just for a visual piece, but not for burning in?
 
Last edited:

Rusty18

Burning Hunk
Nov 3, 2018
134
Belpre oh
Use a small hammer, I repeat small hammer and tap the end of the bolt to get it broke loose then soak with penetrating oil. Once it is broke you can put a nut over it and weld the stub to the nut to have something to put a wrench on. If you can’t get it broke loose with the hammer then I second the drill and tap.
disclaimer! Hitting old metal apparatuses with a hammer sometimes makes other stuff break, stuff you don’t want to break...
 

EatenByLimestone

Minister of Fire
You can use heat/cold cycles to try to break it loose too. But I'd try the penetrating oil first. Everybody has their favorite, but Kroil has worked well for me. Heat can also help penetrating oil wick into the space between the bolt and stove.

 

Frenchman

New Member
Mar 17, 2021
30
France
That's a real problem but someone here will know the answer with all the talent we have on this forum and I who knows nothing--wonder about a "blacksmith or someone" like that to take it too...How old is your French antique stove? I wonder about it just breaking off like that and would other areas just break off like that too and it looks maybe welded or a high heat connection with the foot--no screw edges in that bolt--weird but interesting as well...Hope someone has some educated suggestions on how to solve the problem.. mrs clancey
Thanks a lot for your answer!

I don't know the exact age of that stove, either first half of the 20th century, or 19th century :)
 

Frenchman

New Member
Mar 17, 2021
30
France
That stove base is in bad shape. This could happen again because the leg has lost the backing plate behind it where it attaches to the stove. That puts a lot of stress on the bolt.
Thanks a lot for the reply. I think you nailed it!

I think you guessed perfectly why the "bolt" broke. Indeed the plate is broken, and thus that foot was not as rigidly stuck against it.

Are you fixing this up just for a visual piece, but not for burning in?
This is not a stove that is used daily, it used to be a few decades ago and we now keep it mostly religiously :) However we have used it this year to boil maple sap to make maple syrup, and I would like to be able to burn again in it in the future, though not daily.

Sometimes it ends up easier to drill it out if the metals are fused together, then retap the hole.


I was also wondering whether the best thing to do would be to drill everything out. Do you have any more hints on that? I was told cast iron easily splits. Is there any precaution I could take to avoid that?

Thanks again very much!
 

Frenchman

New Member
Mar 17, 2021
30
France
Use a small hammer, I repeat small hammer and tap the end of the bolt to get it broke loose then soak with penetrating oil. Once it is broke you can put a nut over it and weld the stub to the nut to have something to put a wrench on. If you can’t get it broke loose with the hammer then I second the drill and tap.
disclaimer! Hitting old metal apparatuses with a hammer sometimes makes other stuff break, stuff you don’t want to break...

Thank you very much for the help!

Yes, I forgot to mention that. Right after pouring some old gasoline, I tapped gently with a small hammer each time. The problem is that there doesn't seem to be any crevasses for the oil to penetrate, even after using a hammer.
 

Frenchman

New Member
Mar 17, 2021
30
France
You can use heat/cold cycles to try to break it loose too. But I'd try the penetrating oil first. Everybody has their favorite, but Kroil has worked well for me. Heat can also help penetrating oil wick into the space between the bolt and stove.

Thank you very much again for the swift reply!

I read about the heat as a solution to break things loose. Unfortunately I don't have any blowtorch :(

I was thinking old gasoline oil could act as penetrating oil, but unfortunately I can't find any space between the bolt and the stove...
 

Corey

Minister of Fire
Nov 19, 2005
2,628
Midwest
I would think the hole on the leg would be clearanced for the bolt/screw. (things get pretty tricky if the leg-hole and the stove-hole are both threaded!) So the old screw portion 'should' just tap out of the leg, being careful to use a bunch of support and not tap too hard. If it doesn't, then guess the only other thing would be to drill it out.

I'd suspect the piece on the stove was threaded at one point - but given the age, ashes, rust heat, that is likely fused solid, too. Given the looks of all the old cast iron, you'd want to be extremely careful putting much force or hammering on anything.

If you have access to the back side of the portion in the stove (which I guess would be the top/inside the firebox as it normally sits), it might be easier to just drill clearance holes in both pieces, then use a bolt/screw with a nut / washer to hold everything together. That way you don't have to worry about threading a hole.

Good luck!
 

EatenByLimestone

Minister of Fire
You can buy cheap torches where plumbing supplies are sold.
 

begreen

Mooderator
Staff member
Nov 18, 2005
91,422
South Puget Sound, WA
I am not sure what resources are in your community, but if the intention is to keep the stove and use it, I would try to find someone with a plasma cutter and have a new base plate cut out of thick 5mm steel.
 

Frenchman

New Member
Mar 17, 2021
30
France
I would think the hole on the leg would be clearanced for the bolt/screw. (things get pretty tricky if the leg-hole and the stove-hole are both threaded!)

That is very smart! I hadn't thought about that.

So the old screw portion 'should' just tap out of the leg, being careful to use a bunch of support and not tap too hard. If it doesn't, then guess the only other thing would be to drill it out.

Do you have any hints on that? Can I use any metal drill bit? Is there any risk I would break the cast iron?

I'd suspect the piece on the stove was threaded at one point - but given the age, ashes, rust heat, that is likely fused solid, too.
So I am not crazy, am I? It did "fuse"? Is that common? Is it rust melting into the iron?

If you have access to the back side of the portion in the stove (which I guess would be the top/inside the firebox as it normally sits), it might be easier to just drill clearance holes in both pieces, then use a bolt/screw with a nut / washer to hold everything together. That way you don't have to worry about threading a hole.
I could absolutely do that, as long as drilling doesn't break everything.

Good luck!
Thanks a lot!
 

Frenchman

New Member
Mar 17, 2021
30
France
I am not sure what resources are in your community, but if the intention is to keep the stove and use it, I would try to find someone with a plasma cutter and have a new base plate cut out of thick 5mm steel.
I'll think about it but the problem, I think, is that the base plate is a really original part. It is the same part that protrudes to the front, providing the ash "balcony", and is pretty stylish
 

begreen

Mooderator
Staff member
Nov 18, 2005
91,422
South Puget Sound, WA
Unless the base can be made solid again so that the leg safely supports the weight, I would not burn in this stove. A leg collapse when the stove is hot and full of fire could be very dangerous.
 
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Frenchman

New Member
Mar 17, 2021
30
France
Unless the base can be made solid again so that the leg safely supports the weight, I would not burn in this stove. A leg collapse when the stove is hot and full of fire could be very dangerous.
Thanks for the insights.

I forgot to mention that I don't think we will ever burn in it indoors. Anyway it is forbidden now, at least in France, to connect several stoves to the same pipe, and we have a much bigger stove for heating the house. I plan to burn in it only outdoors, to make maple syrup or traditional waffles :)

Before I started derusting it, it was still standing without a problem. It is my rubbing that made the leg move back and forth and ultimately broke it.
 

Corey

Minister of Fire
Nov 19, 2005
2,628
Midwest
If I had to drill the bolt out, I would try to grind the existing surfaces as flat as possible first. On the leg, you could support from below, then use a center punch to make a small dimple in the center of the bolt, then drill that out with a nice sharp/new metal bit. On the stove, I'd be a bit afraid to use a center punch as it doesn't seem like you can support that metal well and a blow from the hammer might break the metal. You could try to use a 'center drill' which is a short stubby bit which will be easier to start and keep centered. Once you get a dimple started, then you can switch to a normal bit to drill the hole.


Not sure what the scope of this whole project is, but given the looks of the bottom of the stove and the length / relatively unsupported nature of those legs, it looks like other remaining legs might not be too strong either. You might consider getting a piece of plate steel cut in a shape to fit the bottom of the stove, then bolting the legs to that and sitting your stove on this newly made steel 'table'. I would think 1/4 inch (6mm) steel would be plenty strong for that application and should not be too expensive. Just a thought.
 

begreen

Mooderator
Staff member
Nov 18, 2005
91,422
South Puget Sound, WA
Thanks for the insights.

I forgot to mention that I don't think we will ever burn in it indoors. Anyway it is forbidden now, at least in France, to connect several stoves to the same pipe, and we have a much bigger stove for heating the house. I plan to burn in it only outdoors, to make maple syrup or traditional waffles :)

Before I started derusting it, it was still standing without a problem. It is my rubbing that made the leg move back and forth and ultimately broke it.
If outdoors, set that corner or maybe the entire stove on a cement blocks.
 

moresnow

Minister of Fire
Jan 13, 2015
1,922
Iowa
plan to burn in it only outdoors, to make maple syrup or traditional waffles :)
Sooooooo. Definitely going to need a few pics of some traditional waffles with home made maple syrup:)
 

Frenchman

New Member
Mar 17, 2021
30
France
If I had to drill the bolt out, I would try to grind the existing surfaces as flat as possible first. On the leg, you could support from below, then use a center punch to make a small dimple in the center of the bolt, then drill that out with a nice sharp/new metal bit. On the stove, I'd be a bit afraid to use a center punch as it doesn't seem like you can support that metal well and a blow from the hammer might break the metal. You could try to use a 'center drill' which is a short stubby bit which will be easier to start and keep centered. Once you get a dimple started, then you can switch to a normal bit to drill the hole.


Thanks a lot for these very detailed instructions! It is very helpful! I'll definitely try that then.

Not sure what the scope of this whole project is, but given the looks of the bottom of the stove and the length / relatively unsupported nature of those legs, it looks like other remaining legs might not be too strong either. You might consider getting a piece of plate steel cut in a shape to fit the bottom of the stove, then bolting the legs to that and sitting your stove on this newly made steel 'table'. I would think 1/4 inch (6mm) steel would be plenty strong for that application and should not be too expensive. Just a thought.
The other legs seem very solid. They are not moving at all, and they are pretty thick.

The project for now is simply to get the stove back in the state where I found it before damaging it.

In the future I could very well try to add a steel plate below. One of the reasons why I am hesitant to do that is that this would mean removing the other legs, with the risk of breaking more things. Given how difficult it is, and likely will be, to remove the bolt from that broken leg, I expect other legs to be at least as difficult.

Thanks a lot for your insights on that front too though, it will definitely help me when I tackle this matter!
 

Frenchman

New Member
Mar 17, 2021
30
France
Sooooooo. Definitely going to need a few pics of some traditional waffles with home made maple syrup:)
hahahaha ok! I haven't ever made traditional waffles yet, at that point it is still a wish. When I do, I'll definitely take pictures, and I hope to think about sharing them here.

In the meantime here is a video of when we boiled maple sap into maple syrup on that stove: