When a ring only needs to be sized up by a small amount, there are a few ways that you can size the ring by stretching. Stretching can be done with traditional jewelers tools like a rawhide hammer over a steel mandrel or by using one of several tools that are designed to make the job much quicker.

Some of the processes will work only on plain bands while other techniques and tools will allow you to stretch a ring with mountings, diamonds, or gemstones that are on the ring. These techniques are used on pliable metals such as gold, silver, platinum, and palladium that are solid inside. Rings made of titanium, stainless, cobalt, and other extremely hard metals will not stretch using these tools or methods.

Be aware that there are some rings that were NOT designed to be stretched and that stretching a ring has some potential problems like rings that are made up of more than one type of metal or rings that have gems mounted all the way around.  Jewelers will use a special torch and technique called “annealing” to heat the metal to red-hot and letting it cool slowly to release the tension and make it less likely to crack or break – Read our other guides to learn more about making jewelry.

Stretching a ring using Jewelers Rawhide Hammer

One of the most simple and traditional ways to stretch a ring and make it slightly larger is by using a mandrel and rawhide mallet. This works best for sizing only a small amount and should be used with extreme caution when the ring has any mounted gems or diamonds.

What is required:
Rawhide Jewelers Mallet
Solid Steel Mandrel

Set the ring onto the steel mandrel and check the size. If you are sizing more than 1/2 size, you should use a different method of stretching. Using the rawhide hammer, start to pound on the ring making sure you dont hit the exact same place over and over. If you have a a solid band that has no gems or diamonds, you can hit all sides equally. If there is a mounting or gems, you should only strike on the lower 1/2 of the shank staying away from any gemstones. Hit the ring so it is forced down onto the larger part of the mandrel forcing the metal to stetch and the ring should be 1/8 size larger with only a dozen strikes. once the ring is near fitting, turn the ring over on the mandrel so that both sides get stretched equally.

Now you can polish the ring to a bright shine or just wear it if there is a pattern or finish.

Stretching a ring using the Rathburn ring stretcher

This device is designed for solid wedding bands that have NO mounted gems or diamonds. This sizer works simply by hitting the top with a hammer. It has three components: Base, ring holder, and tapered shaft.

Set the nylon base on a bench or solid surface with the shaft and ring holder on top. Place your ring onto the holder pushing down as far as it will go by hand. Strike firmly on the top of the shaft while holding the device upright. The tapered shaft will force the ring to open wider with each strike. Pause after a few hits to check the size and to push down on the ring to the next larger position.

The ring sizes equally on all sides and should be 1/4 size larger with only about 10 strikes. Turn the ring over to make sure both sides are sized equally. This sizer has very little effect on the surface of rings but after stretching, its good practice to polish or replace your rings finish.

Stretching stone-set rings

This machine was specifically designed to size up rings that have mounted gemstones or diamonds and it works best on rings where the shank is not tapered drastically. It works by rolling over the metal with extreme pressure that quickly changes the size of the ring.

Its a requirement that this tool be mounted to a bench or desk to give you two hands to work


Select the die that fits with the shape and width of your ring. You can hold your ring up to the die to check the couture and shape (match only the “bottom” size of your ring – the size AWAY from the gems) You will be only working on the lower 1/2 of the ring to stretch it.


Insert the correct size die; then the ring is held by hand where it sits on the apposing smooth metal side. Tighten the handle to touch the ring then begin to roll the handle back and forth as your tighten the handle slightly every other time. The ring should be sized up 1/4 size after only a few sequences.

Caution: do not roll to the upper side of the ring or the thicker part of the ring and keep the tool only on the lower part of the ring (inside finger side)


Stretching with a jewelers ring stretcher/reducer

This heavy duty tool was designed to quickly stretch and shrink rings every day. You can stretch solid wedding bands that have NO mounted gems or diamonds with this powerful machine.

The top part with the mandrel has the ring sizes conveniently listed and the handle easily applies the required power and leverage to stretch your wedding bands.  sizes 1-15 US.

The base has 16 reduction ring sizes to make rings smaller.



Sizing your ring can be an easy task if you have the right tools.