JMI Medium Universal Wheeley Bar — Telescope Dolly

Product Overview

The JMI Medium Universal Wheeley Bar is the standard-duty model in JMI's Universal Wheeley Bar line: a welded steel base on locking wheels that carries a fully assembled tripod-mounted telescope from storage to the observing spot in one piece. It is rated for 50 lb total — tripod, mount, OTA and accessories combined — and fits tripods with a tip-to-tip spread between 32.3″ and 36.8″. Tripod feet drop into receptacles of 2-1/4″ inside diameter, which take feet up to 2″ across. The standard package uses 2-3/8″ locking caster wheels and 1/2″ leveling screws. The frame is welded steel with a powder-coat finish, made in the USA, and the bar ships at 40 lb.

Who It's For

This is a good match if you store a tripod-mounted telescope assembled and want to roll it out with cables, camera and power supply still attached; if the complete rig weighs 50 lb or less; and if the tripod, at observing height, measures between 32.3″ and 36.8″ from foot tip to foot tip. It is also a good match if the route runs over a smooth garage floor, driveway or patio, which is the ground the standard 2-3/8″ casters are sized for.

Key Features & Design

• 50 lb load rating: Covers the tripod, mount, optical tube and every accessory riding with them.
• 32.3″–36.8″ tip-to-tip range: The arms adjust across that span, so one bar covers a range of common tripod footprints.
• 2-1/4″ foot receptacles: Each receptacle has a 2-1/4″ inside diameter and takes tripod feet up to 2″ in diameter.
• 2-3/8″ locking casters: Hard-rubber wheels that lock at the observing position so the base stays where it is put.
• 1/2″ leveling screws: Threaded screws take the load off the wheels and bring the base level once parked.
• Two wheel upgrade paths: 5″ polyurethane wheels raise the setup about 6″, and 10″ pneumatic tires raise it about 3.5″.
• Welded steel frame: Powder-coated welded steel, made in the USA, 40 lb as shipped.

Mechanical Design

Arms radiate from a welded steel centre, each ending in a cup that captures one tripod foot. The tripod sits in the cups rather than bolting down, so the telescope's own weight holds the geometry. Each arm carries a locking caster and a 1/2″ leveling screw: the casters roll the load, and the leveling screws thread down at the observing position to lift the frame onto fixed points, which takes the wheels out of the vibration path and levels the base on uneven concrete. Because the tripod is never taken apart, polar alignment, cable routing and balance survive the trip.

Recommended Uses

• Rolling an assembled visual rig from a garage or shed out to a driveway or patio pad.
• Returning the same telescope to the same observing position night after night with alignment intact.
• Moving a tripod-mounted refractor or an 8″ catadioptric with diagonal, eyepieces and power supply attached.
• Repositioning a setup mid-session to clear a tree line or a roofline.
• Parking a telescope in a corner of the garage and wheeling it out without lifting it.

Compatibility and Accessory Notes

Fit is decided by the tripod's tip-to-tip measurement at observing height, taken between any two feet: this model covers 32.3″ to 36.8″. The receptacles have a 2-1/4″ inside diameter and accept feet up to 2″ in diameter. The load ceiling is 50 lb for the whole assembly; JMI's Heavy-Duty Shorty, Heavy-Duty Medium and Heavy-Duty Large bars are rated to 300 lb and cover 26.25″–31.25″, 34″–42.5″ and 49″–56.5″ respectively. This bar uses 1/2″ leveling screws, so the 1/2″ versions of JMI's wheel upgrades, tow handle and soft-ground feet are the matching parts. Optional 5″ polyurethane wheels raise the setup about 6″, and 10″ pneumatic tires raise it about 3.5″. Tie-down bracket kits are sold separately. Tell us the make and model of your tripod and we will confirm the fit.

Good to Know Before You Order

• The 50 lb rating covers everything on the bar. Tripod, mount, counterweights, optical tube, camera and power supply all count toward it. Imaging rigs commonly run past 50 lb, and JMI's Heavy-Duty models are rated to 300 lb.
• The standard 2-3/8″ casters are sized for hard, flat ground. Grass, gravel and mulch are the ground the 10″ pneumatic tires are made for.
• Wheel upgrades change the working height. 5″ polyurethane wheels raise the setup about 6″ and 10″ pneumatic tires raise it about 3.5″, which shifts both the eyepiece position and the tip-to-tip figure to measure against.
• Doorway clearance with the 10″ tires. JMI's published allowance is a doorway at least 3″ wider than the tip-to-tip distance.
• Wheel upgrades, tow handle and tie-down brackets are separate items. They are ordered on their own, in the 1/2″ leveling-screw version for this bar.
• Weight as shipped is 40 lb. The bar arrives as a welded steel frame in one carton.

Frequently Asked Questions

Is it difficult to set up?

The bar arrives as a welded frame. Setup is a matter of spreading the arms to the tripod's tip-to-tip measurement, lowering the tripod feet into the cups, and running the leveling screws down once the telescope is parked. Nothing on the tripod is modified or drilled.

How is tip-to-tip distance measured?

With the tripod at its observing height, the measurement runs between any two foot tips. For this model that figure falls between 32.3″ and 36.8″. With 5″ wheels the setup sits about 6″ higher and with 10″ pneumatic tires about 3.5″ higher, so the measurement is taken with that allowance in mind.

Does the telescope stay aligned?

The tripod is never taken apart, so polar alignment, cable routing and counterweight position stay as they were. Returning to a marked spot on the pad reproduces the same alignment closely.

What surfaces does it roll on?

The 2-3/8″ hard-rubber casters are at home on smooth concrete, asphalt and patio pavers. Cracked concrete suits the 5″ polyurethane wheels, and grass, dirt and gravel suit the 10″ pneumatic tires.

Does it carry an imaging rig?

It carries 50 lb total. A German equatorial mount with counterweights, optical tube and imaging train usually runs past that figure, and the 300 lb Heavy-Duty models cover those loads.

Bottom Line

In short: a 50 lb standard-duty steel dolly for tripods measuring 32.3″ to 36.8″ tip to tip, on locking 2-3/8″ casters with 1/2″ leveling screws, so an assembled visual rig rolls out and rolls back in one trip. Welded steel, made in the USA, 40 lb as shipped.