Lesso America Lesso 4'' 45 Degree Elbow Pipe fitting - ABS DWV fittings

Why I reached for a 45° ABS elbow

I used this 4-inch 45° ABS elbow from Lesso to re-route a basement DWV run around a joist bay without resorting to a full 90° turn. In gravity drains, gentler changes in direction matter—especially on lines that see lint, paper, or the occasional debris. A 45° keeps flow moving and reduces the odds of snags, which is exactly what I wanted.

Build and finish

The Lesso elbow presents as a robust, hub‑to‑hub fitting with clean sockets, uniform wall thickness, and a deep, well-defined stop. The black ABS has a consistent sheen and no visible molding defects or flash. Edges were properly chamfered out of the box; I still hit the pipe ends with a deburring tool, but I didn’t have to correct the fitting itself.

Interior smoothness stands out. The bore feels slick to the touch, and you can see the polish compared to some commodity fittings. Claims about low surface roughness are hard to verify in a shop, but the finish is better than average and that’s what counts in day-to-day use.

Despite being a large 4-inch part, it’s light enough to hold overhead for a dry‑fit without fatigue. ABS is inherently impact resistant, and this elbow feels sturdy without being bulky. It’s a far cry from cast‑iron weight, and that’s welcome in retrofit work where one person needs to manage alignment, solvent cement, and level.

A note on labeling: the size markings are clear, and the angle is accurately molded. Ignore any generic catalog copy you might see about “right‑angle, 90° connections”—this is a true 45° hub‑to‑hub elbow.

Fit and installation

I paired the elbow with standard 4-inch ABS DWV pipe (IPS OD). The interference fit was right where I want it: snug enough to hold alignment during dry‑fit, not so tight that solvent cement turns the insertion into a wrestling match. Socket depth was consistent across both hubs.

My install sequence:
- Deburr and bevel the pipe ends.
- Clean the mating surfaces.
- Apply ABS solvent cement evenly to pipe and socket.
- Insert with a quarter‑turn to spread cement; hold for ~10–15 seconds until set.
- Wipe the squeeze‑out bead.

Capillary action drew the cement uniformly; the telltale bead was continuous all around. After a 2‑hour ambient cure, I air‑tested the run at low pressure typical for DWV testing—no weeping at the joints. The elbow held alignment without creep as the cement set.

Two practical tips:
- If you need a compound angle (out of plane), you’ll need a second fitting or a street 45 to clock the turn. This elbow changes direction on a single plane.
- If you’re adapting to PVC, use an appropriate transition cement per your local code. Straight ABS cement is not for ABS‑to‑PVC bonds.

Flow and acoustic behavior

In use, the elbow behaves the way a good 45° should: no audible gurgling or sloshing, and clean downstream scouring. Compared with a nearby 90° long sweep on the same run, the 45° section is quieter under peak discharge from an upstairs bathroom. That’s not lab science, but it tracks with what I expect from a gentler redirection and the smoother bore.

From a hydraulics standpoint, a 45° fitting imposes less head loss than a 90°, which helps on marginal slope runs and reduces the chances of deposit formation. The smooth interior surface doesn’t make a dramatic difference in short stretches, but it adds up across a system—especially where soap, lint, or fine solids are common.

Durability and environment

ABS is a good choice for DWV: it resists many household chemicals and a wide pH range, and it’s indifferent to the occasional temperature spike from hot water discharge within code limits. Impact resistance is better than rigid PVC, which I appreciate in basements and garages where accidental bumps happen.

Exposure caveat: ABS and sunlight don’t mix well over the long term. If parts of your system will live outdoors or in direct UV, shield them or use a UV‑rated paint. Indoors and in concealed spaces, this is a non-issue.

Temperature caveat: DWV fittings aren’t for sustained high‑temperature or pressurized service. Keep this out of hot industrial process lines, hydronics, and any system expecting continuous pressure.

Compatibility notes

This elbow is sized for 4-inch ABS DWV (IPS OD ~4.5"). It will not mate directly with thin‑wall sewer and drain pipe like ASTM D2729 or SDR‑35 (OD ~4.215"). If you’re building a dust‑collection network or lawn drain with thin‑wall S&D, you’ll need adapters designed for that standard. For shop dust collection, remember that these hubs are deep and heavy‑duty; they aren’t a slip‑fit solution for lightweight, thin‑wall ducting.

If you’re mixing materials or standards, check local code and use the right couplings:
- ABS to PVC: listed transition cement or a shielded transition coupling (e.g., no‑hub style) if permitted.
- Cast iron to ABS: shielded no‑hub couplings sized correctly for the OD.

Code and markings

The fitting carries legible size and angle markings and arrived free of cosmetic defects. Code officials typically look for listings/standards on DWV fittings (e.g., ASTM references and third‑party certification). Always verify that what you’re installing bears the markings required by your jurisdiction and that ABS is accepted for the application; some regions have specific preferences between ABS and PVC for residential DWV.

Use cases that suit this elbow

• Re‑routing drains around framing without sharp turns.
• Staging two 45s to approximate a long sweep where space is at a premium.
• Vent line offsets where you want minimal flow disruption and quieter operation.
• Chemical‑resistant, non‑pressurized process drains within ABS temperature limits.

Scenarios where I would pick something else:
- Outdoor, UV‑exposed runs without the option to shield or paint.
- Pressurized water or hydronic systems.
- Thin‑wall S&D or dust‑collection systems unless you have the right adapters.

What stood out in practice

Strength and precision are the two themes. The hubs are true and round, the sockets are clean, and the interference fit feels intentional rather than variable. The interior finish is better than the bargain‑bin fittings you find in bulk bins, and that’s meaningful for keeping lines clear.

The other standout is predictability. A 45° is a simple part; I care that it glues up the same way every time, that it doesn’t ovalize under hand pressure, and that it doesn’t wander when the cement grabs. This one behaved exactly the way I want during a ceiling‑level install where I couldn’t spare a third hand.

If I have a gripe, it’s purely about product page chatter you may see elsewhere—terms like “furniture grade” or mixed mentions of other angles aren’t helpful for a DWV fitting. In the shop, though, the elbow itself avoids those distractions by being well‑made and straightforward.

Bottom line

The Lesso 4‑inch 45° ABS elbow is a solid, no‑surprises DWV fitting with clean sockets, a smooth interior, and reliable glue‑up behavior. It’s light, impact‑resistant, and sized correctly for standard ABS pipe. Use it where a gentle change in direction will improve flow and reduce noise, and be mindful of material standards if you’re crossing into thin‑wall S&D or mixed‑material systems.

Recommendation: I recommend this elbow for residential and light commercial DWV work where ABS is permitted. It’s well‑made, installs predictably, and the 45° geometry is the right tool for keeping drains efficient and quiet. Verify compatibility with your pipe standard and protect it from UV if it will see daylight, and it will do its job without calling attention to itself—which is exactly what a fitting should do.