Portable Cat-segregator




Introduction: Portable Cat-segregator

About: Licensed quantum mechanic. Experienced cat-herder (literal and figurative). Aspiring open-sourceress. Linguam (note the "u") legalicum loquor.

Cats sometimes have to be confined to a limited space.  They're sick, or new, or visiting, or very young, or have to have special food and a chance to eat it in peace. Ot some other householder is allergic, or very young, or moving furniture, or working with {power tools, toxic chemicals, fire, irresistibly tempting people-food}.  And a crate or cage is just too small is many situations.

 1. Sometimes the most suitable area doesn't have a door, and
 2. Even when it does, there are few things most cats HATE!! more than a closed door.  
    - They'll shoot through like lightning the nanosecond you open the door.  
    - If you don't open the door they may make an insufferable racket until you do.
    - And it's almost impossible to convince them they're not being abandoned or punished.
3. Hip-high "pet gates" sold in stores do not faze any able-bodied feline older than about 2 weeks.  
    - The usual reaction is "Hey, thanks for the jungle gym, helper-monkey!"  
    - New-mommy cats even climb over carrying their kittens.

Like a regular door, this barrier protects the entire doorway.  
Unlike a regular door,
  - It  lets air, light, and sound through so the cat feels less isolated and doesn't get as upset.
  - It's climbable without making lots of noise.  
  - A helper-monkey like you can get (or just reach) in and out without creating escape space around your shins.  
  - Putting it up requires no tools and leaves no marks.  
  - And, partially disassembled, it rolls up for transport and storage or parts can be "used for the other use!"

Although designed with cats in mind, it would probably work for under-20-pound dogs, many birds, large lizards (iguanas, tegus, monitors), lemurs, tarsiers, coatimundis, sloths (jeez I want a sloth!!); in short, anything that likes to get altitude but isn't majorly heavy and wouldn't consider vinyl aviary netting a tender yummy dessert.

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Step 1: Parts Is Parts

Dimensions are based on a US standard doorway, 36x80"  (91x203cm).  They'll tolerate plus-or-minus a few inches, but if you've got something really different like a double door or narrow "pocket" door you'll want to measure it and scale up or down,

ADJUSTABLE LOCKING TENSION RODS (they make these for shower curtains.  If you can't find ones long enough search under "tension poles."
  - 2 rods adjustable from (at most) 30"(76cm) to (at least) 40" (102cm).
  - 2 rods adjustable from (at most) 75"(191cm) to (at least) 85" (216cm).

GRIPPER SHEET (you want something a bit compressible with a lot of static friction.  Those lacey-rubbery pads for on shelves and under rugs work well),  64 sq." (163 sq, cm)

MESH, 2 pc., 24"(61cm)x96"(244cm).  I prefer plastic aviary netting: it's very strong, just stiff enough, the holes are just big enough to admit a scritching-finger, a treat or a small toy, and the cut edges won't shred your skin (which after all is Kitty's job).

HEAVY-DUTY HOOK-AND-LOOP TAPE, e.g. Industrial Strength Velcro (TM): 2"(5cm)x96"(244cm).  Usually this is adhesive-backed; if yours isn't, get a strong adhesive that stays flexible.

FOIL TAPE, 2"(5cm)x192"(488cm).  High-performance duct tape can be substituted or added as an underlayer for the foil tape.  The thing about foil is, cats don't like clawing it, for roughly the same reason we don't like chewing it.

CABLE-TIES, preferably the releasable/re-usable kind, 30-40ea., 8"(20cm) long,

CUTTING TOOLS: Heavy-duty shears. small sharp slicing blade

RUBBER GLOVES (optional, not shown)

Step 2: Prevent Slip-ups (or -downs)

Here's how to beef up the strength of the cat-segregator and still be gentle with the surrounding woodwork.

Cut the gripper sheet material into a rectangle that can be folded over twice and still cover the end-cap of a rod

Fold them, wrap all layers around a rod end-cap, and secure with a cable-tie

Cover all the other rod ends the same way.

Step 3: Get Closure

(This closure lets you go through the barrier in EITHER direction and quickly seal it up behind you.  You peel the hook-and-loop tape apart from the middle to open up a gap only as tall and wide as you need, making it hard for even a coordinated team of cats to escape).

(If the hook-and-loop tape is adhesive with a peel-off backing)* SCORE the backing lengthwise down the middle (slicing through the backing but not the tape underneath, so the tape will stay in one piece and the backing will come off in two long half-strips).  Do this to both the "loop" (fuzzy) strip and the "hook" (raspy) strip.  This lets you expose only the sticky area you're immediately ready to stick on.  Otherwise it will do its best to stick to itself wherever you're not holding on, and it's very hard to unstick from itself.

FOLD AND STICK THE *LOOP* SIDE OF THE TAPE FUZZY-SIDE-OUT ALONG A LONG EDGE OF ONE OF THE MESH PIECES.  This is the hook-and-loop strip that will be most exposed when you go through the gap, so you'd rather have it be the fuzzy strip which is less inclined to grab your clothes, hair, etc.

  - Position the long edge of the mesh against the slice you scored down the middle of the backing.  Bit by bit, from the end, peel off the backing strip that's underneath the mesh and stick the mesh to the adhesive.  

  - When you get to the end, fold the other section of loop-tape back over the edge of the mesh.  Then peel the backing off bit by bit and press the adhesive side down onto the edge of the mesh (and through the mesh to the other sticky-side of the tape).  Now the mesh piece should have one of its long edges bound with loop-tape, fuzzy side out.


 - Line up a long edge of the OTHER mesh piece with the FAR EDGE of the hook-tape (whole width of tape is under the mesh).  Bit by bit, peel up the half of the backing that's closest to the mesh edge and stick the mesh to the adhesive.  

When you get to the end, fold the hook-tape in half with the raspy side IN.  Here it'll help to pinch a crease down the middle of the hook-tape while the backing is still on, so it's easier to keep folded over during the next step.


  - Line up the foil tape with the edge of the mesh on top of the stuck-on loop tape.  Stick the foil tape to the mesh and through the holes to the back of the hook-tape. Go all the way to the end and cut the foil tape.

  - Flip the piece over to expose the side of the hook-tape that still has the backing attached.  Line up a new free end of the foil tape over the foil tape that's already stuck onto the other side of the mesh.  .Bit by bit, peel off the hook-tape backing and unroll foil tape to cover the back of the hook-tape and the adjacent mesh. 


Separate the flaps of hook-tape to expose the raspy surfaces. Put the mesh pieces side by side, tape-bound edges together, to make one big rectangle.  Stick the fuzzy-bound edge between the raspy flaps and press together to close the closure.

*If your hook-and-loop tape isn't "sticky-backed,"  you can attach it to the mesh with an epoxy or cement that stays flexible when it dries. Or hand-sew it on.  Or machine-sew it if your machine is heavy-duty enough (regular household ones might not be).  Or even use staples if the sharp ends won't stick out.  Once it's secured in place, put the foil tape over the back of the hook-tape as described above.

Step 4: Put-er-up!

When you're ready to segregate cats, 

  - Coarse-adjust one of the short rods just an inch (2-3cm) or so less than your doorway's width.  (The rods I found use screw-threads for adjustment, which can take a while.  If you get "almost there" with the rod down on the ground, you won't have to spend much time holding it way up over your head).
 - Place the rod near one end of the mesh-panel pair, with the closure near the midpoint of the rod.
 - Fold any excess mesh inward so the mesh-panel width = the rod length (or just an inch or two wider).
 - Wrap the near end of the mesh-panel pair over the rod.
 - Note where you'll have to put your hands to adjust and lock the rod.  Leave that space free for now, and secure the rest of the wrapped mesh to the rod with cable-ties.  Spaces of 6-10" (15-25cm) between cable-ties are fine; no need to secure every mesh-hole.

INSTALL THE TOP ROD  (Note how, on this doorway that has a conventional door, we mount the segregator past where the door closes so the door can still be used with the segregator up).
  - Position the rod at the very top of the doorframe, leaving a climbing cat no space to gain leverage.
  - With the locking ring UNlocked, adjust the rod length to get the strongest bracing force you can.  (Here, and whenever you tighten one of these rods, you might want rubber gloves to get a really good grip,  Pliers and vise-grips aren't ideal for this because they can scratch and squash the rod).
  - Lock the locking ring.
  - Finish securing the mesh to the rod.

 - If the locking ring locks and unlocks by sliding along the rod, as with these, orient the side rods so that the ring slides DOWN to lock.  (That way, when things wobble or settle or get fiddled with by clever claws, Mr. Gravity will be your friend and keep the ring in the locked position).
 - Slide the rod into the "pocket" formed by the folded-over excess mesh width.  Position the top end inside the pocket, against the top of the doorframe, right behind the top rod.
 - There should be some excess length of mesh on the floor.  Position the bottom end of the rod on top of the excess length, pinning it to the floor,
  - Check that the rod is vertical, so it won't slip.
  - Tighten the daylights out of, and lock, the side rod,
  - Secure the excess mesh width "pocket" around the rod with cable-ties,
  - Repeat for the other side rod.

  - Position the bottom rod on the floor directly below the top rod, on top of the excess mesh length.
  - Tighten the daylights out of it and lock it.
  - Fold the excess mesh length up around the bottom rod and secure with cable-ties.

Do a little dance - You're Done!  

To go through, grab hold of the closure at chest height.  Peel the loop-tape and hook-tape apart just enough to make a gap you can safely and comfortably step through.  BE CAREFUL not to snag your foot and trip - remember that this isn't the kind of door you're used to, pay attention to your balance and where you're stepping, and be aware that I am not rich and suing me wouldn't be worth it.

You might not even have to go all the way through all the time; to operate a nearby light-switch or insert/remove a food dish, just open enough of a gap to reach your arm through.

Step 5: Hey! Extra Bonus! Play Sculpture!

When your Cat Segregator is not in use, you can remove the long side rods and roll the mesh up around the short top/bottom rods for easy transport and storage.  OR. . . you can twist the mesh into fantastic shapes and make it into an easily variable or stowable exercise structure!  

- Wrap the mesh around, or drape it over or against, something you already have (chair, table, railing, footboard, windowsill - something reasonably stable and durable).  You can leave the rods in the mesh, or nor.

  - Use cable-ties, small bungees, or clamps to temporarily anchor it.

  - Sprinkle it with catnip, hang toys (e,g, a Rough-House Toy Mouse - see my other Instructable) or carpet-scraps or rope bits on it, et cetera - oh, and initially tell the cats this is YOUR sculpture and they should stay away from it.  Then let them "wear you down" into letting them climb it.

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    6 Discussions


    8 years ago on Introduction

    Fantastic! It's good to have beta testers to point out weaknesses in the system from the beginning :D


    Reply 6 years ago on Introduction

    How did the car barrier go? I had used a large dog kennel lately and was thinking how easy a fold down closet wire shelving thing would be to just keep in the back of the SUV, also helps contain groceries, my big dog...future vet visits for cats...I put smaller cages in side then litter and food can be outside their vet visit cage... Do you have more ideas now? (have you seen my cat walk. smile)


    8 years ago on Introduction

    How about using furniture felt on the end of the curtain rods ,,, they usually come in the shape that fit on the botton of chair so they can grip without causing marks ,,, then you do not have to use cable ties,,


    Reply 8 years ago on Introduction

    Thanks! I imagine it would be excellent for protecting the woodwork. It would also look more civilized than the shelf-liner / cable-tie version. I just wonder how "grippy" it would be on something like gloss enamel. I'll have to run it by the test crew next time I put one up. Meanwhile, if anyone else gives it a try, please let us know how it works!


    8 years ago on Introduction

    A little adjustments and this would work as a pet barrier when traveling with your favorite pets,,,


    Reply 8 years ago on Introduction

    Thanks!  Funny you should mention that; I have to take multiple cats to adoption fairs every week so I'm working on that very thing! I'm trying:

    1. a structure that's fairly amorphous (easy to adapt to different vehicles and pack other things "around")
    2. fully enclosed (in case of mess, yank it out and hose it off)
    3. aviary netting on the top to admit scritches and treats, let the cats see you (less anxiety), and the surroundings (less car-sickness),
    4. a tarp on the bottom (protect upholstery, plus many cats enjoy the crackle),
    5. bungee suspension from headrests & seatbelt-hooks (no dents in the ceiling, unobstructed rear view for the driver).
    First proto results:
    1. Need some kind of a frame to support the aviary netting; It sags & the cats find it claustrophobic.  
    2. For multiple cats, need some kind of double "door" to keep Cats 1 through N in while loading Cat N.
    3. Tarp coating had poor adhesion.  First cat got out in <7min by yanking the duct tape, and the tarp-coating it was stuck to, right off the tarp!