Drum Sander vs Orbital Sander for Deck Refinishing

Refurbishing a wood deck can be a satisfying DIY project that adds value and enjoyment to your home. An essential step in deck restoration is sanding down the surface to remove old finish, weathering, and splinters. Choosing the right sander for this demanding task is key to achieving a smooth, even finish on your deck boards. The two most common options are drum sanders and orbital sanders. Which is better for preparing a deck for new stain or sealant? Here’s an in-depth look at the pros and cons of each sander type.

What is a Drum Sander?

A drum sander uses a rotating cylindrical drum covered in sandpaper to abrade wood surfaces. The drum rotates at a high speed for aggressive stock removal. As pressure is applied, the spinning drum sander smooths and flattens the wood surface.

Drum sanders are available as handheld models, ideal for smaller jobs. Larger open-frame drum sanders use conveyor belts to feed the workpiece steadily through the machine. These benchtop or stand-mounted drum sanders are suitable for surfacing large tabletops or flooring.

Drum Sander Advantages

Removes Material Quickly: The high-speed rotating drum can rapidly strip away multiple layers of old finish or weathered wood fiber. This makes drum sanders ideal for dealing with damaged, warped, or uneven decks.
Flattens Surface: Applying consistent downward pressure across the drum sander ensures a uniformly flat surface, ideal for preparing a deck for even and optimal stain absorption.
Leaves Straight Edge: The fixed width of a drum sander gives you a straight edge along borders, eliminating the need to edge by hand after sanding a large area.

Easy to Handle: Handheld drum sanders are lightweight enough for prolonged use and can sand up to edges and walls. Conveyor feed drum sanders require minimal physical effort.
Dust Collection: Many drum sanders can be connected to a shop vacuum system for efficient dust extraction during sanding.

Drum Sander Limitations

Not for Finishing: Drum sanders leave deep linear scratches not suitable as a final finish. You need to follow up with a random orbital sander and progressively finer grits to erase these marks.

Fixed Width: The narrow sanding path means a drum sander covers less surface area on each pass compared to a disc or orbital sander. Sanding a large deck will take more time and effort.
Learning Curve: New users often apply too much pressure resulting in uneven sanding. It takes practice to learn the optimal downward force.
Risk of Gouging: The aggressive cutting action of a drum sander increases the risk of accidentally gouging the wood if not used with care.

High Price: Drum sanders suitable for surfacing decks are a significant investment for a home DIYer. Quality handheld models cost over $200, while benchtop drum sanders exceed $700.

What is an Orbital Sander?

Orbital sanders have a rectangular or round sanding pad that vibrates in tiny, rapid orbits. This creates a scratch pattern that ensures finer finishes. There are several orbital sander types:

Sheet Orbital Sanders: Use flexible sheets of sandpaper that can be easily changed when worn or clogged. Ideal for finishing work on decks.

Quarter-Sheet Orbital Sanders: Smaller size makes them easy to grip and control for intermediate sanding.
Half-Sheet Orbital Sanders: Balance power with sufficient palm size area for sanding large surfaces like decks.
Random Orbital Sanders: Counter-rotating heads to reduce swirl marks with speed variance for added smoothness. Most versatile orbital sander type.

Rotary Orbital Sanders: Spin and oscillate for fast stock removal. Used mostly for initial sanding and leveling.

Orbital Sander Benefits

Versatility: With multiple sizes and operating motions available, orbital sanders can perform all stages of sanding – from initial smoothing to final polishing.
User-Friendly: Lightweight, simple to control, and easy to master for beginners. Sheet paper changes quickly.

Even Finish: Randomized sanding pattern prevents visible scratch marks on surfaces like deck boards. Leaves a uniform texture.
Low Risk of Damage: Gentler motion is forgiving for newcomers. Less chance of unintentionally gouging the deck wood while sanding.
Affordable: Orbital sanders are competitively priced between $50-$150 for home DIYers. Sheet paper is an economical consumable.

Orbital Sander Weaknesses

Slower Stock Removal: The oscillating mechanism is not as aggressive at removing multiple layers of aged wood finish compared to a drum sander.
Overheating Risk: Friction from extended use can burn deck wood if sander is held in one spot too long. Requires careful technique.
Dust Control Difficult: The open orbital mechanism makes dust containment a challenge compared to drum sanders. Lots of airborne dust created.

Hand Sanding of Edges: Unable to sand up to edges of a deck. You’ll still need to do some hand or detail orbital sanding to finish borders.
Burn-Through Potential: Amateurs can unintentionally remove too much material resulting in sanding divots if not careful with pressure applied.

Now that we’ve compared the pros and cons of both sander types, let’s look at some specific recommendations for sanding a wood deck.

Which Sander is Best for Deck Refinishing?

While a drum sander makes fast work of removing many layers of old deck stain or sealer, most DIYers will achieve better results using an orbital sander for restoring deck boards. Here are some tips on choosing the best orbital sander and sandpaper grits.

Random Orbital Sanders

For refinishing decking, a random orbital sander with at least a 5-inch sanding disc is recommended. Models in the 5- to 6-inch range balance power and control for ideal handling on raised deck surfaces. These middle-of-the-road random orbital sanders have enough “oomph” to remove old deck coatings relatively quickly, while still being safe for amateur users.

Many feature variable speed settings (usually around 8,000-12,000 OPM) which aids in moderating the sanding pace depending on if you are doing an initial heavy cut or final finish polishing. Speed adjustment helps prevent accidental burn throughs.

Look for orbital sanders with dust collection ports so you can attach a vacuum hose to contain the vast quantities of sawdust generated while sanding a deck. Built-in dust bags on orbital sanders tend to fill up quickly.

Sheet orbital sanders, where standard sandpaper sheets are affixed using clamps or hook-and-loop fasteners, are recommended over fixed-pad orbital sanders. This allows rapid paper changes when the current grit clogs up during use.

Highly-rated 5-inch random orbital sanders suitable for DIY deck refinishing include:

DeWALT DWE6423 5″ Variable Speed Random Orbit Sander
Bosch ROS20VSC Random Orbit Sander
Makita BO5041K 5″ Random Orbit Sander

Festool ETS EC 150/5 EQ Random Orbital Sander

These quality sanders provide the optimal balance of sanding effectiveness and safety for refurbishing deck boards. While more powerful rotary orbital sanders quickly remove material, they are prone to leaving visible scratch marks if not used properly. Stick with a medium 5-6 inch random orbital sander and take your time for best deck restoration results.

Sandpaper Grit Recommendations

The sandpaper grit sequence you move through is also important for achieving a smooth deck surface ready for new protective sealant. Here are some orbital sander grit guidelines:

40-60 grit to aggressively remove failing top coatings down to bare wood
80 grit to smooth any rough areas and evenly flatten deck
100 grit to erase coarse sanding marks

120-150 grit for final polish before finish application

Always sand longitudinally along the wood grain, not across deck boards. Thoroughly vacuum between sanding stages to remove all dust. Consider using a dust mask and eye protection when sanding, especially during the initial stripping with coarse grit papers which creates substantial airborne sawdust.

Grits finer than 150 are not recommended when preparing a deck surface, since you want the wood to still have some open texture to absorb the protective coating. Make sure to remove all dust before applying deck stains, paints, or sealers so they properly adhere.

Tips for Sanding a Deck with an Orbital Sander

Here are some best practices to follow when using a random orbital sander to restore your deck:

Inspect all deck boards prior to sanding. Replace any severely damaged or rotting deck planks first.
Wet down deck with water before sanding to control airborne dust. This allows particles to settle instead of drifting onto surrounding surfaces.

Always move the sander in the direction of the wood grain for best cut and finish. Work methodically board-by-board.
Apply light downward pressure and move the sander in a steady pattern to evenly abrade the surface. Avoid lingering in one spot.
When edges start rounding over, swap out the sandpaper for a fresh sheet. Don’t wait until paper is fully clogged.

Periodically vacuum dust buildup underneath the deck boards to improve cut and reduce flying particles.
Wear quality eye and breathing protection! Brace yourself for copious amounts of fine dust generated while sanding a deck.
Sand only when the wood moisture content is below 15% to avoid sanding issues and raised wood grain.

Finish sanding by hand in hard-to-reach areas like spindles, corners and around railings.
Do a final thorough sweep, vacuum and wipe-down of the deck before applying new protective finishes.

Proper use of a random orbital sander along with patience and care will transform a gray, splintered deck into a smooth and even surface ready for staining. Always allow adequate drying time before and after sanding weathered deck boards. With the right preparation, your refinished deck will look amazing and perform beautifully for years to come.

Advantages of Drum Sanders for Deck Refinishing

While most DIYers are better off using a random orbital sander for deck restoration, in certain scenarios a drum sander can be the right choice:

Severely Damaged and Uneven Decks

When dealing with extremely deteriorated, warped and uneven decking, a drum sander offers some advantages:

The aggressive cutting action quickly strips away badly weathered and splintered surface wood fibers.

Drum sanders flatten low spots and can level badly cupped or distorted deck planks in poor condition.
They leave a uniformly smooth and flat surface ideal for accepting new protective coatings.

So if tackling a totally neglected and badly damaged deck, consider renting an open-frame conveyor drum sander to do the initial flattening and surfacing before switching to orbital sanders.

Large Commercial Deck Resurfacing

For refinishing massive residential or commercial deck projects, a conveyor drum sander saves huge amounts of time compared to hand sanding thousands of square feet. Companies that specialize in large deck refinishing jobs often utilize drum sanders due to:

The rapid stock removal capacity compared to orbital sanders.
The wide sanding path up to 30 inches to quickly cover more surface area.

Minimal physical exertion using conveyor feed mechanisms.
Built-in dust collection with commercial models.

So while still requiring significant skill to operate properly, drum sanders can excel at rapidly resanding large decks if used by a professional refinishing contractor.

Renting for One-Off Projects

Occasionally, a home DIYer may want to consider renting a drum sander for a deck restoration project. Examples where renting a drum sander might make sense include:

Sanding down a large deck (500+ sq. ft.) as a one-time project. The rental cost can be offset by the labor hours saved using a drum vs orbital sander.
Refinishing specialty woods like ipe or tigerwood whose extreme density can quickly clog orbital sandpaper. A drum sander’s continuous cutting action handles these exotic hardwoods more efficiently.

For a relatively small price, you can rent an aggressive handheld drum sander from home improvement stores to make fast work of removing weathered deck finishes before polishing with your own orbital sander. Just take care to avoid over-sanding or gouging the wood.

While orbital sanders are better suited for most deck refinishing jobs, in the right circumstances a drum sander can save huge amounts of time and effort preparing a large or severely damaged deck surface.

Key Differences Between Drum Sanders and Orbital Sanders

To summarize the major differences:

Drum sanders are best for:

Rapid removal of material from weathered decks
Flattening uneven, warped, or distorted deck boards

Leaving highly consistent flat surfaces
Sanding jobs requiring less physical exertion

Orbital sanders excel at:

Faster coverage of surface area with random action
Attaining perfectly smooth finishes without swirl marks
Fine sanding and polishing to prep for protective coatings

Versatility for all stages of sanding
Being user-friendly for DIYers to operate safely

In most cases, a combination of both sander types yields optimal results:

Drum sander to aggressively strip and flatten the deck
Orbital sander to refine the surface and prep for staining

Understanding the strengths and weaknesses of each will lead to making the best choice for your specific deck refinishing needs.

Orbital vs Drum Sanders: Which is Easier for a Beginner?

For DIYers refurbishing their first deck, an orbital sander is decidedly easier to use than a drum sander. Here’s why:

Orbital sanders are designed for one-handed operation and are lightweight. Controlling a heavy drum sander with two hands is more difficult.
The smooth back-and-forth orbital action is very forgiving. It’s harder for a new user to damage the deck with an orbital versus a drum sander.

Sheet sandpaper on orbital models is effortless to change when clogged. Drum sanders require dismounting the drum itself to swap sanding belts.
Orbital sanders can utilize finer grits and leave flawless smooth sanded surfaces. Drum sanders only remove material and require further finishing.
Large drum sanders are intimidating devices better suited to professional shops. Orbital sanders are compact and dexterous.

Orbital sanders sands flush to edges with overlapping motion. Drum sanders leave ridges and need handwork to finish edges.

For first-time deck refinishers, there is no question an orbital sander is easier to handle safely. Only after extensive experience should DIYers consider using a drum sander for deck restoration. Their unforgiving powerful removal action raises the risk of harming the deck surface.

Are Drum Sanders Dangerous for Deck Refinishing?

Drum sanders demand respect and care on the part of the operator to avoid potentially damaging a deck surface. Here are some risks novice users should keep in mind:

Applying too much downward pressure can rapidly remove too much wood, resulting in sanding divots or ridges.
Not paying close attention can allow the spinning drum to linger too long in one area, burning or gouging the deck boards.
Letting the moving drum touch fixed edges of the deck will result in rapid erosion or notching of the deck surface perimeter.

Catching the rotating drum on loose deck planks or protruding screws/nails can cause violent kickback or shattering.
Fingers or hands getting too close to the spinning drum is extremely dangerous and can cause severe injury if accidentally contacted.

However, with proper precautions and practice, drum sanders can safely perform aggressive surfacing of decks when used gently:

Adjusting belt tension and feed rate prevents over-cutting.
Watching the sanding interface prevents burning or dwell marks.
Starting drum before contacting deck prevents kickback.

Keeping hands safely away from drum while in motion avoids contact injuries.
Wearing protective equipment like goggles & ear protection is a must.

A major mistake beginners make is applying too much downward force rather than allowing the inherent cutting action of the sander to smoothly remove the required amount of material. Respect the power of drum sanders and employ extra care until you gain experience using them. With prudent operation, drum sanders can effectively refinish decks without mishaps.

What Size Orbital Sander is Best for Refinishing Decks?

When selecting an orbital sander for restoring exterior wood decks, a 5-inch model hits the sweet spot for DIYers. Several factors make the 5” size ideal:

Large enough surface area to smooth deck planks efficiently without excessive passes.
Small enough to easily control on raised decking surfaces. Avoid tiring 6”+ models.

Comfortably fits average-sized hands to wield for prolonged periods.
Weighs just 3-5 lbs. for maneuverability yet has ample power.
Rule of thumb: Use largest sander your hands can still guide adeptly. Don’t overestimate your wrist strength!

Many quality orbital sanders like the Bosch ROS20VSC or DeWALT DWE6423 come in 5” size.

Other Orbital Sander Size Options

While 5 inches is optimal, other orbital sander sizes have benefits depending on your specific needs:

3-4 inch orbital sanders are great for:

Detail sanding of deck rails, balusters, stairs, and tight spots.
Finer grit final finish sanding where extra control is needed.
People with smaller hands who need a lighter compact sander.

6 inch orbital sanders are useful for:

Deck resurfacing jobs with huge surface areas or severe damage.
Users with larger hands who want more power.

Fast removal of multiple old finish layers.

Just ensure you pick a size that allows a secure comfortable grip for the duration of your sanding job. Don’t sacrifice dexterity for added surface area coverage.

Corded or Cordless Orbital Sanders?

Corded electric orbital sanders provide consistent power for extended use. But dealing with a power cord can be annoying when working on a spacious deck.

Battery-powered cordless orbital sanders provide exceptional freedom of movement unencumbered by a cord. Popular lithium-ion models from DeWALT, Makita, Bosch, and other brands supply ample runtime between charges.

Just be sure to invest in a quality model that delivers sufficient torque while minimizing hand fatigue. Test sanders in the store for loudness, vibrations, and ease of handling before purchasing.

For small to mid-sized deck refinishing projects, a cordless 5” random orbital sander is hard to beat for flexibility. Keep an extra charged battery or two on hand to ensure uptime.

Choosing the Best Orbital Sander for Deck Refinishing

With many orbital sander brands and models available, it can be tough deciding which is best for restoring your weathered deck. Here are the key features to look for in a deck sander:

Variable Speed Dial – Allows adjusting OPM from 8,000 to 12,000 typically. Slower for finish sanding, faster for stripping coats.

1/4 Sheet Orbital – Uses smaller sheets for detail work and costs less per sheet vs full sheets.

Trigger Switch – Keeps sander running continuously without tiring your hands. Some have speed dials also.

Removable Dust Bag – Containment is better than no bag. But frequent emptying will be required.

Through-Pad Dust Collection – Directly connects sander to vacuum hose for superior dust extraction.

Multi-Stage Filtering – Important if not connecting to vac. Captures fine dust before exhausting.

Ergonomic Grip Areas – Check for padded zones and indentations to hold comfortably without hand strain.

Low-Profile Design – Compact sander critical for sanding under deck rails and fitting in tight areas.

Variable-Speed – Allows tuning the orbits per minute as needed for more delicate finishing work.

Powerful Motor – Seek at least 2 amps of power for quickest stock removal on weathered decks.

Highly rated orbital sanders from Ridgid, Bosch, Makita, DeWALT, and Festool excel at refinishing wood decks. Always use quality sandpaper and change it often for best performance.

Recommended Grit Progression for Orbital-Sanding a Deck

Following a gradual progression of sandpaper grits is vital to achieving a blemish-free, ultra-smooth deck surface.

Here is a proven grit sequence:

40-60 Grit – Aggressively strips away failing top finish layers. Use 60 grit on softer cedar and redwood decks.

80 Grit – Removes any remaining old coating and evens out the surface.
100 Grit – Smoothes rougher areas while providing a fresh texture for new finish.
120 Grit – Further refines the wood grain to a near-finished smoothness.

150-180 Grit – Light final sanding/polishing for an ultra-fine finish.

Always thoroughly vacuum dust between grit changes to prevent surface scratching. And sand parallel to wood grain orientation avoid cross-grain scratches.

The key is gradual progression. Skipping too many steps can result in an uneven, wavy surface. Be patient and allow sufficient sanding time per grit for flawless results.

Tips for Orbital-Sanding Decks

Work plank-by-plank to maintain focus and thorough sanding pattern.
Apply light even pressure. Let the sander do the work of removing material.
Keep the sander moving to prevent heat buildup, swirls or dish-out depressions.
Periodically check underdeck for accumulated sawdust and vacuum to remove.
Wear a dust mask! You’ll be breathing a lot of fine airborne wood dust.
Watch for areas of insect damage or rot during sanding and replace boards as needed.
Sand smooth any popped wood grain before applying finish so it doesn’t telegraph through.
Always sand in direction of wood grain. Never sand in a circular or diagonal motion.

Follow these tips and your refinished deck will look like new again and maintain its beauty for years using the right sanding technique.

How to Sand Hard to Reach Areas of a Deck

While a random orbital sander makes fast work of sanding the easy open deck board areas, tight spots under railings, around posts, and on stairs present challenges. Here are some options for sanding cramped areas of your deck:

Use detail orbital sanders like the Bosch ROS10 or Festool ETS-EC Brush to access tight spaces between balusters and rails. Their compact triangular shape allows close-up operation.
Corner finisher power tools outfitted with sanding discs zip into 90-degree areas. Great for sanding the riser recesses on deck steps.
Detail sanding sponges are handy for quick touch ups and feathering edges in confined spots. Look for long narrow profiles sized around 2″ x 5″.
For spindle columns or diagonal deck supports, wrap sandpaper around a slender dowel rod secured with tape for improvised detail sanding.
Sand stair treads and difficult areas by hand using firm rubber sanding blocks and a selection of grits. Kneeling helps best access awkward areas.
Where a fixed railing limit sanding access, use sandpaper wrapped around a short piece of 1″ dowel and work under the rail.
Stick self-adhesive sandpaper sheets to scrap wood tongue depressors for finishing tight spots and deck board edges.

With some creativity and the right narrow-profile accessories, you can successfully sand even cramped areas of your deck prior to applying protective finish. Don’t neglect those hidden surfaces that still require smoothing and prep.

Common Orbital Sander Problems When Refinishing Decks

Orbital sanders make deck resurfacing much easier compared to hand sanding, but they can still present some challenges:

Rough Uneven Finish

The sander was held in one spot too long without moving, creating depressions. Keep it moving!

Swirl Marks Visible

Changing sanding direction instead of consistent wood grain motion causes circular scratches.

Burn Marks Present

Friction from prolonged pressure in an area overheated the wood. Avoid lingering.

Torn Grain

Moving against wood grain direction lifts and tears softer fibers. Always go with the grain.

Chatter Marks

Sanding too aggressively with overly coarse grits causes chattering vibration marks. Use finer grits.

Clogged Paper

Failing to swap sandpaper when loaded causes poor sanding cut and finish quality. Change sheets more frequently.

Wavy Uneven Surface

Skipping too many grits leaves a bumpy finish. Use proper progression from coarse to fine.

Excessive Dust

Lack of vacuuming results in scratched finish from grit embedded in dust. Vacuum thoroughly between sanding stages.

Raised Grain

Exposure to moisture swells fibers that sanding then exaggerates. Keep wood dry.

Following best orbital sanding practices for deck refinishing avoids most of these potential issues. Patience and care pays off in a blemish-free, ultra-smooth sanded deck surface.

Wet Sanding Decks with an Orbital Sander?

While many woodworkers utilize the wet sanding technique for items like dining tables, wet sanding exterior wood decks with an orbital sander carries risks:

Risk of Water Damage – Introducing moisture into deck boards can cause swelling, warping, fastener corrosion, and rot over time.

Raised Grain – Water causes surface fibers to swell upward, exaggerating grain when sanded. Results in rough feel requiring extra sanding.

Staining Issues – Water raises wood grain which prevents uniform stain penetration for blotchy appearance.

Safety Hazards – Wet boards become slippery, electrical shock risk if sander cord gets wet, and wet sawdust sticks everywhere.

Messy Clean Up – Damp wood, water, and wet sawdust makes a muddy mess requiring extensive clean up afterward.

** Orbital Sander Damage** – Water can seep into power sander motor cavities over time, shorting out electrical components. Voids your warranty.

Longer Dry Times Required – Before and after wet sanding, sufficient drying is needed to prevent mold, mildew, and trapped moisture issues. Adds delays.

The key is using sharp fresh sandpaper and changing it frequently. This eliminates the perceived need to introduce water which can create a slew of other problems.

Is Hand Sanding a Deck Better than Using a Power Sander?

While hand sanding with blocks and sheets will get the job done, power sanders greatly speed up refurbishing a deck. Advantages of using an orbital sander versus hand sanding include:

Faster removal of weathered wood and old deck finishes. Saves hours of labor.
A smooth even finish not realistically achievable with inconsistent hand motions.
Less physically exhausting than the non-stop arm motion of hand sanding. Reduces fatigue.
Built-in dust collection to control airborne sawdust. Hand sanding creates substantial messy dust.
Consistent pressure applied for uniform smoothing without risk of uneven spots.
Easier edged sanding with models that accept quarter-sheet paper or round pads.

However, hand sanding still plays an important role in deck preparation:

Hand sanding tight areas around posts, railings, gaps and stairs orbital sanders can’t reach.
Final touch up hand sanding of any spots the power sander missed.
Hand sanding with a sanding pole for overhead surfaces like floor joists and deck undersides.

For best results, combine power and hand sanding. Use the orbital sander to rapidly flatten and smooth the majority of the deck, followed by handwork in difficult areas. This provides efficiency along with complete surface coverage.

In summary, orbital sanders save huge amounts of time and provide superior finish quality on open deck sections. But hand sanding remains essential for completing final touch up work in tricky areas. Use both techniques for professional deck refinishing results.