Presto canner with slightly bulged bottom

[manygoatsnmore]

Is there any reason why I should NOT use a canner whose bottom isn't completely flat?

[wally]

Pretty sure most canners that are used have some bulged bottoms. Mine do as we do a lot of canning. I would like to hear from some all American canners

[feather]

I only have one pressure canner and it's not all-american, it's something old.
I haven't run across any bulging. I don't have as much experience with them as you two probably do.

[Tim Horton]

None of Sweeties All American canners have bulged bottoms. Actually, none of her other brand canners have bulged bottoms either. All are second hand, thrift store, garage sale units. Even the most scruffy All American we got last summer cleaned up and rebuilt into the one she used all this last fall.

I have seen several bulge bottom, non AA canners at the thrift store. Even with senior discount they want way too much money for them even to experiment with. One day I will find one for a decent price to hack up. My intention is to install what is called a bulk head fitting in the lid. This attaches to a standard size copper tube on both ends. I want to essentially make a crude still to distill water with. This being an experiment to convert unfiltered well water to distilled water in case of an emergency situation where potable water is scarce.

[mogal]

I wouldn't have any problem using one as Tim Horton described to distill water but never would I use one as a pressure canner any longer. If it's starting to bulge, it could blow and I don't think that would be a particularly fun experience.

I wish I could cite chapter and verse but I read somewhere that a canner with a bulging bottom isn't safe.

Just my 2 cents

[ohiodreamer]

I have one that is mildly bulging. When I took it to the free "canner check" a few years back the "expert" said it was fine if not canning on an electric stove. Gas allows for more "non perfect" bases. Electric stoves have to have perfectly flat. Comes down to how "non-flat" is it?

[janinco]

For what it's worth, my sister bought a really tall one like the AA but not that brand, from an older couple who used it to can potatoes. She didn't notice, nor did I until I got home with it after she gifted it to me, that the bottom was pretty badly bulged. I asked the extension service here and they said ABSOLUTELY not to use it, they had seen several that had blown up and cracked badly while being used, that the metal would be stressed, etc. I just put it in the recycle, sadly. Better than having it give out while using it. Plus the darn thing was too tall to use under my stove hood.

[Deleted]

What ruins them is too much heat too fast or concentrated in a small area. Many times too small a burner. Don't want to wait so turn it up high, especially the tall one. Takes a lot of heat to get the pressure up, then pressure goes too high. Mine are flat but they have only been used on a wood range and with a wire heat ring under them so the heat spreads evenly....James

[Tim Horton]

In metal sheering, the any material goes through 3 steps to produce the cut. First step is called plastic deformation, second is penetration, third is fracture to complete the seperation.. Depending on thickness and type of metal all go through varing amounts of all 3 steps..

In the case of a canner it will bulge with 1 or 2 of these steps as it is not confined by the cutting blades of the tool... So for instance the bottom of an alluminum canner will plastic deform, and could have fracture more so than other materials.. A stainless canner will have much more plastic deformation and less fracture up to the point of pressure failure...

Anyway... I still plan to try to make a water distiller.. Sweetie has a very nice stainless fruit juice distiller.. Works well for stuff like black currents and the like.. I'm wondering if I could improve on that with the homemade still ??

There is a cute picture of a couple hill billies next to there old still saying... No officer, we are not making moonshine, were making hand sanitizer...