The How's and Whys of Cup Casters
What furniture legs will cup casters fit?
Cup casters fit over the bottom of furniture legs. Choose a round cup for a round leg or a square cup for a square leg. Cups are not a universal fit: the furniture leg must closely match the cup’s interior dimensions. If the measurements differ, the leg may need alteration before the cup will fit.
Begin with the fit of the cup, not the wheel size. Two casters with the same wheel diameter can have different cup dimensions. Check the cup’s interior depth, top measurement, and bottom measurement against your furniture leg.
Then consider wheel size, finish, and how much the caster will raise the furniture.
How do I find the right cup size?
Follow the separate round and square cup measuring instructions below. They show where to measure your furniture leg and which product dimensions to compare before ordering.
How do I measure my furniture leg for round cup casters?
Round cup casters fit round furniture legs. Start with the cup dimensions listed on the product page for the caster you are considering.
- Measure the listed cup depth up from the bottom of the furniture leg and mark that height. This is where the top of the cup will sit.
- At that mark, use calipers or a ruler to measure the leg’s diameter straight across the center. Compare it with the cup’s interior top diameter.
- Measure the diameter straight across the bottom of the leg. Compare it with the cup’s interior bottom diameter.
The leg must closely match both interior diameters. Measuring only the bottom of the leg does not establish whether the cup will fit.
To fit furniture leg size must closely match caster cup dimensions.
How do I measure my furniture leg for square cup casters?
Square cup casters fit square furniture legs. Start with the cup dimensions listed on the product page for the caster you are considering.
- Measure the listed cup depth up from the bottom of the furniture leg and mark that height. This is where the top of the cup will sit.
- At that mark, measure the length of one side of the leg, not diagonally across it. Compare it with the cup’s interior top side length. Check the adjacent side too.
- Measure one side at the bottom of the leg and compare it with the cup’s interior bottom side length. Repeat on the adjacent side.
The leg must closely match the cup’s interior dimensions at both the top and bottom. If the measurements differ, the leg may need alteration before the cup will fit.
What else should I check before ordering?
Check wheel diameter for proportion to the furniture, and use the product’s “Raises Furniture” measurement to determine the added height. Wheel diameter alone does not give the installed height.
Cup Casters are sized with interior cup measurements
What do the interior cup measurements mean?
Interior measurements describe the space available for the furniture leg within the cup. Use these dimensions directly; do not subtract the thickness of the brass wall.
For round cups, the top and bottom measurements are interior diameters. For square cups, they are interior side lengths, not diagonal measurements. The furniture leg must closely match both measurements.
What does the depth of the cup tell me?
Cup depth tells you how far the furniture leg fits into the cup. Measure that distance up from the bottom of the leg to locate where you should take the top diameter or side-length measurement. Use the exact depth listed for your selected caster.
How much will the caster raise my furniture?
Use the “Raises Furniture” measurement on the product page. This is the height added beneath the furniture leg when the caster is correctly fitted. Wheel diameter alone does not tell you how much height the caster adds.
How much weight can cup casters support?
Check the load capacity listed on the individual product page, allowing for both the furniture’s weight and anything it will hold. Correct fit and secure installation are essential to caster strength and stability.
Are cup casters suitable for frequent rolling?
These reproduction furniture casters are intended for occasional movement rather than frequent rolling. The cup must fit snugly around the furniture leg and be securely attached.
