





Whether building a home gym from scratch or adding to an existing setup, weight plates are the foundation of serious training. Sam’s Fitness carries from 20kg Olympic weight plates for the platform to fractional plates as light as 0.5kg for precision progression.
Every weight plate in the range is built to strict tolerances from cast iron, solid steel, and high-density rubber. These aren’t plates that crack after a year of use. They’re built to take drops, chalk, and decades of loading.
Not all weight plates are the same, and the wrong choice can mean buying twice. Here’s what actually matters.
Olympic vs Standard Weight Plates
Olympic weight plates have a 50mm centre hole, designed for 2-inch Olympic barbells. Standard weight plates have a smaller 28–30mm hole and fit 1-inch standard bars. If training with a proper Olympic barbell — which is the standard for home gym use — go Olympic. The fit is tighter, the loadings are safer, and the range of available plates is far wider.
Rubber vs Cast Iron Weight Plates
Cast iron weight plates are the classic choice — dense, compact, and long-lasting when kept dry. Rubber weight plates (sometimes called rubber-coated or bumper plates) protect floors and equipment, reduce noise, and survive accidental drops. For a home gym on a concrete or rubber floor, rubber-coated plates are worth the extra investment. For a commercial setup or platform-based lifting, bumper weight plates are the go-to.
Bumper Plates vs Regular Weight Plates
Bumper weight plates are built from solid rubber with a steel collar insert, designed to be dropped from overhead without damage — essential for Olympic lifting movements like the clean and jerk or snatch. Standard Olympic weight plates are not designed to be dropped repeatedly. If the program involves any Olympic lifts, invest in bumpers.
What About Fractional Plates?
Fractional weight plates — ranging from 0.25kg to 1.25kg — are designed for progressive overload when standard 2.5kg jumps become too large. Serious intermediate and advanced lifters consider them essential. They’re particularly useful on pressing movements where even a 2.5kg jump each side represents a big relative increase.
What Size Set to Buy?
A solid starter set for a home gym covers:
Cast iron / rubber-coated plates are the cheapest per kg and great for general training where you don’t drop the bar. Bumper plates are rubber-encased and designed to be dropped from overhead — required for Olympic weightlifting and CrossFit. Powerlifting (calibrated) plates are thinner and precisely weighted — only needed if you compete in IPF powerlifting. For most home gyms: rubber coated plates are fine. If you do CrossFit or Olympic lifts: bumpers. If you compete: calibrated.
It depends on plate thickness. Standard rubber coated cast iron 20 kg plates are about 45 mm thick — you can stack 9 per side (380 kg total including the bar). Standard bumper plates are 80 mm — you can stack 5 per side (220 kg total). Calibrated powerlifting plates are 19.2 mm — 9 per side (380 kg total). The sleeve length on most ATX and Power Maxx Olympic bars is 415 mm.
As of 2026, expect to pay roughly $4-$6/kg for cast iron Olympic plates, $6-$10/kg for rubber-coated plates, $8-$12/kg for standard bumper plates, and $15-$25/kg for calibrated competition plates. Sam’s prices fluctuate based on steel costs but we hold a best-price guarantee for genuine like-for-like quotes from authorised AU retailers.
No — they’re different standards and not interchangeable. 50mm (or 51mm / 2-inch) is the Olympic standard — fits Olympic barbells with 50mm sleeves. 28mm (or 1-inch) is the older standard plate hole, used on cheap home barbells and dumbbell handles. If you have an Olympic bar, you need 50mm hole plates. All ATX, Power Maxx and Ironmaster plates we stock are 50mm Olympic standard.
For most beginners we recommend starting with 115kg total: 4× 20kg, 2× 10kg, 2× 5kg, 2× 2.5kg, plus collars. This covers everything from light warm-ups to a 135kg bench/squat (with a 20kg bar). As you progress, add 2× 25kg or another pair of 20kg plates.
Rubber weight plates can sometimes go white or grey. This phenomenon is known as blooming. This is what happens when certain ingredients come to the surface of the rubber. This is purely cosmetic, and the rubber is not deteriorating.
Sometimes you can remove the bloom with a quick wipe with a rag. If this does not work, try some mild detergent, and warm water.
Honestly do not stress too much about it. Rubber is a natural product – not synthetic like plastic or nylon – it expands and contracts with heat. Blooming is just part of this process.
In our showroom, especially upstairs on the mezzanine, new weight plates can all go white as soon as the temperature hits a certain point. Heat and humidity will bring it out. If you are in an environment where temperatures fluctuate then don’t spend a lot of time removing blooming. It will come back later.
However, after a while you will notice that in stops.
For general cleaning, just use a duster – we find that is the easiest way to keep plates clean. If you are in a gym with hygiene concerns, you may need to use an antibacterial product. Just check the formulation to make sure that it is suitable for rubber.
Light surface rust on weight plates can sometimes be polished out. An automotive product will be fine. Try this at the first stages of rust. If the rag doesn’t work, then try a nylon bristle brush.
If the rust is more advanced, you will need to use something more abrasive. A steel bristle brush, sandpaper or steel wool will be needed to remove stubborn rust. Bear in mind that this will compromise the surface coating – if not addressed the rust will return. You will need to re-paint the areas if you have had to go hard.
No. Weight plates differ in hole diameter (Olympic 50mm vs standard 28mm), material (cast iron, rubber, urethane), construction quality, and tolerance accuracy. IPF/IWF competition-spec plates are manufactured to tighter weight tolerances than budget plates — the difference matters at competition but less so for general training.