Design and Construction
The 4100's hull is hand laid-up solid fiberglass below the waterline and switched to Baltek balsa coring above it, a scheme that keeps impact resistance low and sheds weight aloft solid fiberglass below the waterline. The laminate alternates strand mat with unidirectional E glass and is vacuum-bagged, while isophthalic polyester and vinylester resins are specified to resist blistering. The deck is balsa-cored, and bulkheads of pressure laminate are tabbed to the hull with mat and roving exactly as the floor grid is. At the sheer, the hull-deck seam is bedded in 3M 5200 and bolted through an aluminum bar, following a Tartan practice of more than twenty years. Rudders are foam-cored fiberglass on 304 stainless stocks, and the lead-ballasted hull carries efficient high-aspect spade rudders. Three keel choices were offered: deep fin, moderate-draft beavertail, and shoal-draft centerboard.
Rig and Handling
The 4100 wears a double-spreader masthead rig with slightly swept-back spreaders and inboard chainplates tucked near the cabin sides, which lets the genoa sheet at narrow angles inboard chainplates. The mast and boom are Offshore Spars products, the backstay splits to clear the stern swim steps, and deck organizers lead mainsail control lines aft to the cockpit where Harken two-speed self-tailers dominate. A rigid vang stands in for a topping lift, which the original reviewers counted as a real safety gain. On the water, test sailors found her sticky in light air as a flat-bottomed hull tends to be, yet she still sailed to 30–35 degrees apparent in 10 knots at 4.5–5 knots, and footing off to 65 degrees in 18 knots lifted speed past 8. Under a full main and 110% genoa in 22 knots she touched 9.5 knots on a close reach, and with the genoa blanketed at 120 degrees she held 8.5 flat and comfortable. She tacked through an estimated 90 degrees and showed only a hint of weather helm at 15 knots. The longer waterline pays off downwind: she would cover San Francisco to Honolulu at least a day quicker than the 3700 and, being heavier, rides more easily offshore.
Accommodations
Below, the saloon runs 9.75 feet long by 7.5 wide with 6-foot 5-inch headroom and 70-inch settees flanking a centerline table whose leaves rise to 44 by 34 inches. Jackett placed an island on the centerline at the companionway foot opposite the L-shaped galley; on the 4100 that island measures 48 by 42 inches and carries double stainless sinks, and a tilt-up counter can seal the galley entirely. The portside galley is U-shaped with a Force 10 three-burner stove and Formica counters, though a Corian-like solid surface was optional. A starboard nav station faces outboard with a 25–27 by 35–39 inch surface. Queen berths sit fore and aft; the aft cabin gets a solid door, teak-and-holly sole, cedar-lined cabinets and over-six-foot headroom, while the forward cabin offers an 82-inch by 77-inch berth at 6-foot 3-inch headroom. The head is 76 by 48 inches at the same headroom, with a folding shower door that stows to the hull.
Deck and Equipment
The side decks are a clean 24 inches wide and the double lifelines, stanchions and pulpits stand 27 inches high. Teak handrails run each side of the cabin top, and six stainless portlights line both sides with large hatches over living spaces and the head plus Dorade vents ahead of the traveler. A twin anchor roller sits offset from centerline, and the cockpit carries a destroyer wheel on a Whitlock system with Ritchie compass and a teak table that folds flush to the pedestal. Engine controls fall readily to hand at the helm, and the well-insulated compartment let testers talk below in normal voices under way well-insulated engine compartment.
The Verdict
The Tartan 4100 is a thoughtfully engineered Jackett cruiser that trades a little light-air liveliness for real offshore composure, a quiet mechanical space, and a bright, sociable interior built around an unusual companionway island.
Pros
- Solid glass bottom with balsa topsides and vacuum-bagged E-glass laminate for blister resistance
- Inboard chainplates and swept spreaders for narrow sheeting and good pointing
- Three keel options including shoal centerboard
- 125-degree positive stability range and flat, buoyant motion in lump
- U-shaped port galley with enclosable island and queen berths both ends
Cons
- Flat-bottomed hull feels sticky in light air
- Balsa-cored deck demands vigilance around any fastener leak











