The larger pet crates can be difficult to handle during travel and there aren't many that have detachable wheels. But now you'll be able to make a lightweight compact dolly that can be stored on top of the crate or easily disassembled.
Step 1: Plan and Measure
- 1-1/4 in PVC pipe
- 4x 1-1/4 in PVC 3-way elbow
- 4x 1-1/4 in PVC caster fitting insert
- PVC primer and cement
- Set of 2 swivel and 2 rigid or locking threaded stem casters with nuts
- Pipe insulation foam
- Rubber cement
- (optional) Friction tape
- (optional) Thread lock
- 4x 5/16 in x 3-3/4 in Eye bolts (total length)
- 4x 5/16 Wing nuts (matching the eye bolts TPI)
- 4x 5/16 Washers
- 4x Bungee cords
- 8ft paracord
- (optional) Short leash with handle
- Measuring tape
- Power drill with 5/16 bit
- ~4 hours of free time
If you haven't worked with PVC I strongly recommend reading the excellent PVC 101, it also has more details on the supplies needed.
To estimate the length of PVC pipe measure the dimensions of the crate's face that will be riding on the dolly. In my case I had a 40x27x30 in crate with a 31x19 in bottom. The PVC elbows add 1-3/4 in to the pipe length when assembled so to make a 31x19 in rectangle I needed two pipes that are 27-1/2 in long and two 15-1/2 in for a total of 86 in or 7 ft 2 in. Since most of the pipe will be covered by the insulation foam you can use plumbing grade PVC.
The foam will add grip and make the ride less bumpy for your pet. It usually comes in smaller diameters than 1-1/4 in, but since we only need to cover the top half 3/4 in inner diameter foam will be enough.
Choosing the correct casters might be tricky as you need two swiveling and two rigid or locking ones for best handling (if you ever tried pulling a cart with 4 swiveling wheels you know what I mean). Also they must have a threaded stem up to 7/16 in diameter and at least 1-1/2 in length. You could still use ones with 1-1/4 long stem, but you'd need to cut the PVC caster inserts to accommodate them.
If possible get rigid casters with brakes for security when getting your pet in and out.
The wheel diameter isn't that important unless you are planning to use the dolly on rough terrain.
The bungee cords will be holding the crate in place using the tie-down holes that most crates should have. Measure the distance from the tie-down hole to the nearest ground-touching corner and add an inch to get the stretched hook-to-hook length. Since bungee cord typically stretches about 50% of the nominal length you would need a cord that's between 0.67 and 0.8 of the stretched length.
In my case the stretched length was 17 in, so 12 in or 13 in cord would work.
Make sure that the hook is wide enough to actually fit around the crate's lip or at least is metallic so it can be bent into the desired shape.
Step 2: Assemble the Frame
- Cut the pipe to the size from previous step. While you don't need to match the crate exactly it is important that the parallel segments of pipe are as close in length as possible so that the frame squares properly.
- Dry fit the parts and ensure all four corners are touching the crate.
- Use the PVC cement to weld the shorter segments to the fittings, one segment at a time and ensuring that all four corners at still touching the crate before the cement settles.
Step 3: Get Your Foam On
- Cut the foam into segments matching the exposed pipe.
- Liberally apply the rubber cement to the inside of a foam segment and the top half of the matching pipe.
- Carefully position the foam over the pipe and press firmly along the whole length.
- (optional) Tightly wrap friction tape over the foam ends for durability as these parts will be under the most stress.
Step 4: Secure the Long Segments With Bolts
- Choose the spot to make the hole for the bolt that will secure the long PVC pipe segment to the fitting. It should be vertically centered and far enough from the corner to accommodate the wing nut that will go on the inside of the frame. Make sure all the holes are at the same distance from the corner so that the pipe segments can be fitted either way when reassembled.
- Drill a pilot hole on both sides of the pipe (for a total of 8 pilot holes).
- Drill through each pair of pilot holes using the 5/16 bit.
- Insert the eye bolts in the holes with the loops on the outside and a washer between the loop and the pipe to distribute the pressure.
- (optional) Apply removable thread lock to the bolts.
- Secure the bolts with wing nuts.
- Attach the paracord using an anchor bend and a couple of half hitches to the bolts on the "front" of the dolly. This is where the swivel wheels will go in.
- (optional) Clip on a short leash with handle to the paracord
Step 5: Add Wheels
- Secure the casters to the PVC caster insert using nuts, tighten with tools.
- (optional) For a permanent assembly add rubber cement to the caster and permanent thread lock to the stem
- Dry fit the wheel assemblies to the frame and roll it around to get a feel.
- (optional) Use PVC cement to permanently bond the wheel assemblies to the fittings. Note that for normal usage this should be unnecessary and doing so will restrict how much the dolly can be disassembled.
Step 6: Final Assembly
- Place the dolly wheels down on the floor.
- Position the crate over it with the door facing the front.
- Stretch bungee cords between the tie-down holes and the eye-bolts
- Make sure that the crate is held firmly and the wheels have the break on before letting your pet in