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How to make a belly cast

Some women love their pregnant bellies, and some women hate ‘em. Either way, they won’t be there forever, and you may just miss them when they are gone! Belly casting is a great and FUN way to create a pregnancy keepsake. Here’s a quick how-to, with a focus on TIPS you may not find when you Google “how to do a belly cast”. Please note that there are a gazillion ways to do a cast, and no way is right or wrong. You may even discover a really cool new way of doing it as you go. The key point though is to create a strong cast that is going to last.

Before you start: Have everything ready before pregnant mamma (“PM” hereafter) sits down to be cast.

 have something to put the cast onto when you remove it from the PM, e.g. a piece of board/flattened old cardboard box, or even a beanbag (this is by far the best option). You may like to support the cast from the inside, using towels or newspaper. Some people have had success using a blown up balloon. See what works for you.
 drop sheet down as workspace
 comfy chair placed on drop sheet (if PM plans to sit), positioned near a table where your supplies will be easily accessible. Office chairs work really well. Ensure feet are planted firmly on the ground.
 old towel on chair (if PM sits on drop sheet on chair she may gradually slip down!) I personally tie towel to chair so it cannot budge – tie where the back meets the seat part. You can even use a scrap of old material to do this. If PM is standing, use fabric drop sheets beneath her.
 cut all the plaster before you begin, and keep it well away from any water. See note below on plaster lengths.
 container for water (wide enough to easily fit your closed fists into and ideally about 25+cm long), kettle boiled and cold water on hand – this is to mix water to dip plaster into. Ensure PM can tolerate water temperature by testing on her wrist. The hotter the better. Water will seem colder when PM is naked!
 bucket of water to wash caster’s hands in
 scissors and old towel/rag
 oil/paw-paw salve or the like – to be put all over PM’s casting area, and surrounds if you like. This stops it sticking to skin and pulling hairs when you remove the cast
 cling wrap to cover undies and bra if PM is wearing one. (It’s best not to though as bra lines will show up, however, if you don’t want to see your breasts hangin’ down a-la-naturale every time you look at your cast, you’d best put that bra back on!)
 camera for some pics
 ensure it’s warm/cool enough, especially for PM (make it warmer than you think you’ll need it)
 turn off phones and create a nice vibe. Think music, smells, lighting etc. Have some drinking water on hand, and whatever else you fancy
 caster and PM go to the loo

A note about plaster lengths….
Every PM’s bump is a different size and shape, and I have found I have needed different plaster lengths/quantities for every cast. My rule of thumb is to have all sorts of lengths available. Start with (in this order of priority):
a) 2 strips the length of hips-to-underarms (vertically) – these will form side strips for the cast
b) 15-20 strips the width of belly at its widest point horizontally (if you don’t use them all they can be cut up smaller and used elsewhere)
c) 4 x 7cm for nipples – 2 on each nipple – Photo No 1.
d) 10 x 10cm (for breasts and tricky places)
e) 10 x 20cm (most likely used across breast area)
f) You’ll probably find that you have some little strips e.g. 4cm left over after cutting the above lengths. These are great for the boob area, where boob sits onto bump. Keep them! And if you don’t naturally end up with them, ensure you have about 10 x 4(ish)cm strips by sacrificing a length from above.
*If you still have plaster left over after cutting these lengths, cut more of (e) lengths, as you can easily cut these down if you need smaller bits as you go.

NB: if you want nice smooth edges on your cast, you will also need probably 4-6 x (b)lengths. We’ll call them (g) lengths. PUT THESE ASIDE for after the cast is dry – see below for how to use these.

Some tips before we begin…

  • Always hold BOTH ENDS of the plaster as you dip it into the water, otherwise it may curl/twist and is a nightmare to straighten out. Continue to hold in this manner until you have placed onto the casting area – Photo No.2
  • Wet one strip at a time. If you get even a drop of water onto the plaster you have cut, before you are ready to use it, it will go off and harden. You’ll then end up with a hard blob amongst the remaining smooth plaster when you eventually use it. Not a disaster by any means, but try to avoid this by placing cut plaster away from the water container, but still within reach
  • Hold plaster vertically over water once dipped. This allows excess water to run away. Do not squeeze all of the water out.
  • After placing each plaster strip onto body, ALWAYS run your wet finger across it repeatedly to loosen the plaster and turn it into a nice smooth finish.
  • Always overlap the strips by 50% – Photo No.1
  • Work quickly but do not rush.
  • Don’t be afraid of making mistakes. Plaster is an amazing medium and you can make improvements after it dries if need be.
  • The cast is ready to remove when it naturally moves away from the body – usually 30 mins after placing the last piece of plaster on.
  • When you put the cast onto the board and newspaper to dry, be sure it’s not pushing the sides out or it will distort the cast. Also, remove this once the cast is dry enough to support itself or the cast will not get enough ventilation to dry further. An hour should be ample.
  • Avoid putting plaster down the sink. Best to wash-up in bucket of water then tip it into the garden & throw it away once it’s set
  • If PM is standing for the cast, have her moved her ankles around every now and then, to get the blood flowing.

Ok…here goes!
1. Ensure cling wrap is over clothes & PM is oiled up!
2. Using (a) lengths, place one strip vertically, running from armpit down to hip, on left and right side. Be sure to place on widest point. If you place too far back you won’t be able to get the cast off!
3. Using (b) lengths start from undies line and work up, HORIZONTALLY, remembering to overlap each piece by 50%.
4. Work your way up to just above the navel and REPEAT. Mentally note where you stopped.
5. Then put 2 x 7cm (c) lengths onto each nipple
6. Using 4cm (f) lengths, cover where breast meets the belly- Photo No.1
7. Using 2 x 20cm (e) lengths, create an X between the breasts on the flat part of the chest. Repeat again.
8. Using 10cm (d) lengths, again cover area where breasts meet the belly (i.e. over the top of the 4cm (f) lengths you placed in step 5. These will mostly be angled vertically.
9. Now go back to where you momentarily stopped casting above the navel, and continue to work your way up over the belly and onto the breasts. It’s ok to change the direction of the plaster as you go. Use whichever lengths feel right. Remember to overlap by 50%!
10. Once you are above the nipple line you will likely find you can use the 20cm (e) lengths. Work methodically from left to right AND horizontally ensuring all areas are covered. It helps to cut the plaster in the middle of the breasts (Photo No.3) and reinforce breast area if need be (Photo No.4)
11. Hopefully you will still have plaster left, so go back to where you stopped just above the navel, and start working upwards again until all areas are covered twice. Remember that where the breast touches the belly and the central chest area are the weaker points, but do not use all your plaster here!!!! Also save a little in case you need to patch anywhere.
12. Note the time and allow the plaster to dry for a minimum of 30 minutes unless the PM absolutely cannot remain sitting any longer! As it dries PM will feel it getting warmer, and pulling away from her skin. It’s ready to come off when it all pulls away without too much help. The trickiest bit is often where the boobs meet the belly. Pull it off slowly and gently as PM wiggles a little bit. Hold it up to the light and you will see any places that need additional plaster – Photo No.5. Put the cast down and plaster over these areas.
13. Place it carefully onto the board. If edges are not dry enough to support the weight without bending, place towels/balloon under the belly area, or place belly down onto beanbag. If you can it’s great to direct a fan onto the cast for an hour or so – this helps with drying.
14. As soon as it’s dry enough on sides to support itself (1 hour should do it), position it so air can circulate. Resist playing with and touching it (hard I know!!!) and leave to dry for 7-10 days.

In terms of what plaster to use, some people have had success using craft grade plaster obtained from $2 shops. Whilst this works out quite cheap, the strength and quality is not as good as using medical grade plaster. It’s like comparing beer and champagne in my and others’ experiences.  I have even had a Mum come to me to buy my plaster after a failed attempt using the craft grade plaster I speak of.

Photographs courtesy of Jane McCrae
IMG_3374IMG_3376-2 IMG_3385-2 IMG_3381 IMG_3403-2


Preparing Edges

Once you have done the cast and it has dried for a few days, you need to trim the edges with SHARP scissors and then finish them off neatly. Be sure to hold the cast up against a wall to see if it sits nicely, and if not, trim as necessary. Once you are happy with how it sits, and the overall shape of cast, you are ready to neaten edges.

1) cut the plaster so that it is half as wide i.e. about 3.5 cm wide. and cut it into lengths about 20-30cm long.

2) spray the edges of your cast with water/dampen with a cloth.

3) grab a piece of plaster, dip it in water as per usual, and then lay it on the edge of cast so that half of the width (i.e. approx 1.5 cm) goes along the front edge, and the other half folds over and covers the back edge.

4) Repeat till all the edges are covered in the fashion.

5) most areas will only need one layer of edging, but if you have a particularly weak point, you may double up.

6) once you have done all edges, leave undisturbed to dry, belly down (pref on a soft pillow/beanbag)

7) allow to dry and then you are ready to render. (it doesn’t have to dry for days and days as you will wet it again when you render. Just make sure it’s dry enough to hold it’s form)


Rendering the cast

Ensure you read the safety instructions and data sheets that should have come with your rendering powder. Here and here.

Render the outside first as doing the inside first can cause the tummy to crumple in!!

To do this:

1)  Use one of the bags of render PER SIDE and do on different days! (allowing a good few days between layers is good!)

2) using a 1/2 cup measuring cup, into a clean bucket, add 3 x 1/2 cups of clean water…and then about 1/4 of a 1/2 cup of water

3) add the powder

4) stir using an old wooden spoon/whisk/paint stirrer. As you stir, stir it on the side of the bucket, so as to push out any lumpy bits (as you would when making a cake)

5) spray whatever side you are about to render, with some water (or wipe with a wet cloth). It needs to be damp not dripping wet.

6) leave the render to sit until it starts to get thicker. When it’s thick enough to pick up in your fingers ( a bit like mud consistency), rub it onto the cast. A mud-like/clay-like consistency is good. But don’t let it get so hard that you can’t spread it!

7) you don’t want to put masses on, as the weight can sometimes be too much for your cast. You want a layer a few mm thick.Work in one area at a time, then move on. Once you have a rough layer (well, as smooth as you can but not perfect), start dipping your hands into water and smoothing out any uneven bits/lumps etc. This will minimise the amount of sanding you have t do.

8) once you have the thickness and smoothness you want, wipe down the sides of the cast to remove any render that has gotten onto the edges or front. Do this BEFORE it dries.

9) place your cast belly DOWN into a bean bag (put towel over bean bag first) when you render the inside, and place it  belly facing the ceiling on a table to dry when you render the outside. It’s great to allow the outside render to dry a few days before you start to do the inside. NB: the inside can be as rough as you like cos no one will see it!

10) once you have rendered the inside and the render is touch dry ( a few hours is good) put it in a place to dry for 7-10 days where it will not be disturbed. The longer it has to dry with the least amount of movement, the better.  In wet weather, it may take longer, but you can speed this up slightly by putting in a room that has an aircon/heater on. BUT do not speed up the drying process too much, and do not place in direct sunlight.

11) once dry, sand back (240 wet n dry is good – used DRY) drill your holes to hang it, undercoat and decorate it, then thread ribbon through the holes.

If you purchased your plaster from me, I am happy to provide you with telephone support, before, during or after your cast is done.

Happy casting!



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