How Tight Should a Ring be When Canning?

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Canning is a popular food storage method. From jams to pickles, many people can each year. The process involves using jars and specially designed lids, and using these two-piece lids correctly is critical to the entire process. 

One of the most common questions I’m asked by new canners is, How tight should a ring be when canning? 

I’m so glad you asked! Here’s the short version answer of how right a ring should be when canning:

When tightening the two-piece canning lids, you need to make sure you make them fingertip tight. Anything tighter or looser than this will result in a failed seal on the jar and more work for you.

Exactly how tight is fingertip tight? And what happens when you under or over-tighten canning bands too much?

Keep reading to find out the answer to these questions and more!

How Do You Put a Lid on a Canning Jar?

Pro tip: avoid buying cheap, knock off lids from Amazon. Unfortunately, many people are selling lids on Amazon that have the Ball or Kerr name but are cheap imitations. No matter what you do, you’ll have a lot of seal failures if you start off with bad lids. I recommend these Superb brand lids that I buy from Lehman’s.

Now, let’s get into the nuts and bolts of how tight a ring should be when canning.

When using two-piece lids:

1. Start by placing the lid on the filled jar.
2. Make sure it is centered and hold it in place with your fingers.
3. Then you will screw down the ring to fingertip tight.
4. It is essential not to tighten these lids further after processing.

Make sure not to use force or jar tighteners when applying this lid type. Air is forced out of the jar during processing, and this air cannot escape if you tighten the screw band too much.

If the air cannot escape, the lid will buckle, causing it not to seal correctly. As the hot air escapes, it creates a vacuum to seal the jar as it cools.

What is the Purpose of the Ring?

The canning ring has nothing to do with creating a seal on your jar. It serves one temporary function: to simply hold the actual flat lid in place during the heat processing.

If you did not have a canning ring, the cover would get lost in the canner, creating no seal.

Once the jar has cooled and the seal created, the canning ring is no longer needed. You will then take it off and store it until it is needed again.

What is Finger Tight (or Fingertip Tight)?

I remember when I first started canning, and everyone told me to screw on the rings fingertip tight, I had no idea what they were talking about! If the term confuses you, you’re certainly not alone!

Fingertip tight is the very vague term given to the level of tightness you should provide to your canning ring. Like me, many new canners wonder what exactly this term means.

One way to explain this is to say that you should apply gentle force from your fingers and not force from your whole arm.

Another way to understand this is to think about what you do when you are trying to untighten a lid. Most likely you put more than your fingers into it! When a lid is tight, you grasp onto it with your whole hand, and even put force from some of your body into it.

This type of force is the exact opposite of what you want to do when tightening a canning lid. Instead of using your whole hand and arm when putting on a canning ring, use only your fingers to tighten the band.

You will also not use a tool of any kind to assist in the tightening. You will just snug the ring and not apply any more force.

One way to ensure your canning ring is fingertip tight is to place the ring on the jar and turn it just until you feel resistance. Next, you will need to turn the ring one-quarter turn more. 

What Happens When You Don’t Tighten Bands Enough?

If you do not tighten your bands enough, you may not get your jars to seal. Loose bands allow for too much venting.

Additionally, liquid may escape from the jars during processing. If this happens, food particles can end up on the rim of the jar, preventing the lid from sealing.

What Happens When You Tighten Bands Too Much?

Overtightening rings may prevent the air from venting out of the jars, and this, in turn, will cause buckled lids or seal failure.

Buckled lids result from the air forcing its way out of the jar any way it can. Because the lids become deformed through this process, the seal cannot form correctly.

Buckling caused by over-tightening rings is immediately apparent after heat processing.

Two-piece canning lids are designed specifically to release pressure and vent air from the jar during heat processing. As the jar is heated, pressure increases in the headspace until excess air vents from the jar. There is no way for this to happen when the band is applied too tightly. The result is that the pressure buildup warps the lid, disrupting the seal formation.

Additionally, bands may appear to loosen after processing. This is completely normal, and nothing at all to worry about.

Now if you’re like me, and you notice the rings are loose after processing, you may be tempted to retighten them. Do not, I repeat, regardless of how bad you want to, don’t retighten the bands!

Retightening will result in you breaking the seal that is forming.

How Do You Test a Canning Lid Seal?

The Finger Test Method is the most common method for testing the seal on a jar. All you have to do is press on the middle of the lid with your finger:

• If the lid pops, it is not sealed and must be processed again.
• If there is no movement, it is (most likely) sealed.

You must not test the seal on your canned goods until they have cooled completely, and you have allowed them to seal for several hours. Testing too early might create unsafe food and a false seal. If you need to reprocess any food, do so within 12 hours of the original processing.

Another test you can try is the Spoon Test Method.

You will need to tap the lid with the base of a spoon. A dull sound means the lid is not sealed, while a pinging sound means it is sealed.

It is important to note that if there is no headspace and the food is all the way to the lid, there will be a dull sound either way, and this method will not work for you.

Finally, there is the visual test method. If the lid appears to be bulging or flat, you will need to reprocess the jar. If it seems to be concave, it is properly sealed.

What to Do with Canning Rings Once Your Jars are Sealed

After you’ve finished the canning process, and your jars have cooled and sealed, it’s time to take the rings off. Removing the rings gives you another opportunity to test the lids to make sure they’re sealed. After I remove the rings, I always like to pull up on the flats to make sure they’re tight. Until I remove the rings, I’m never completely sure.

In addition to that, if you leave the rings on the jars once they’re sealed, you’ll have no way of knowing if the seal broke. Keeping the rings on the jars after they’ve sealed can create a false seal. And trust me, you want to know if the jars have come unsealed while in storage.

The good news is, while reusing canning lids is frowned upon, it’s fine to reuse the canning rings, if they’re in undamaged shape.

Pro tip: To learn more about reusing lids, read the article, Can Canning Lids be Reused? | Tips to Reuse Canning Lids

What to Do with All Those Extra Canning Rings

I do want to deal with one problem that canners often have when it comes to canning rings, and that is that since they don’t store them with the filled jars, they end up with a ton of canning rings. If you have a lot of full canning jars in your prepper pantry, you may find that you have more rings than you know what to do with. You may even find that you don’t have room to store all of them!

There are a couple of ways to handle having more canning bands than you know what to do with.

The first suggestion that I have for you is to only keep canning rings that are in excellent condition. Once canning bands start to rust, are bent, or damaged in any other way, toss them!

If you can’t bring yourself to get rid of any of your used canning rings, you may loosely put them onto the filled jars. Just don’t ever screw them even slightly tight once you’ve finished the canning process.

You can also use a mason jar lid organizer such as this one that I found on Amazon.

Conclusion

There are two types of canners when it comes to putting the lid on:

1. Many people overthink the step of placing the lid on canning jars.
2. Others don’t give it a second thought and slap it on.

I cannot overstate how crucial correctly tightening the ring is in the canning process! If you don’t tighten it just right, you can create more work for yourself.

Or worse? You put your family at friends at risk of being exposed to bad food.

No pressure, though. 🙂

The lid must be placed on the jar fingertip tight, meaning apply with just the pressure of the fingers and no more. Anything more or less will result in a failed seal.

Practice Makes Perfect!

If you feel at all overwhelmed by this, let me give you a bit of encouragement. The more you can, the easier this gets.’

I do recommend starting with easy and inexpensive canning projects so that if your jars come unsealed, any waste is minimal. Believe it or not, when I first started canning, I practiced by canning water! This removed the intimidation factor because I wasn’t worried about ruining expensive food. I highly recommend you do the same.

Successful canning can result in having all kinds of foods available. As long as you do it the correct way, canning is a rewarding, safe, and cost-effective method of food storage.