When walking the ICEBOX® around the igloo and checking to see if the ledge is the same size on the outside of the form, keep in mind that you can add to the ledge as you build the igloo. It is easier to add a ledge to the uphill side of the igloo, so you should position the stake so you have a ledge on the downhill side.
For the first layer, the Form Handler kneels, straddling the pole. This position works best as it is easy to pack with your right hand and hold the form steady with your left hand.
The person gathering the snow should place the snow on the ledge directly outside the form. It is best that just enough snow be gathered for each block. If to much snow is gathered and you leave it, expecting to use it later, it will sinter and be hard when you get back to the snow pile to use it. It is best that any extra snow is used to either build the ledge wider or bring it along to the next block. Bringing it along to the next block doesn't require to much energy if the pile is small but a large pile requires a lot of energy to move.
The person putting the snow into the form should be standing on the ledge about 2 or 3 feet ahead of the form. He should be able to pick up the snow and put it into the form without stepping or moving.
When standing in this postition, the snow can be thrown into the form and impacted into the rear wall of snow and not jar the form.
As you begin to build a complete block, the form handler pulls slightly on the top left corner of the form, top left for the Form Handler standing or kneeling inside the igloo, until the form is bowed and the pressure is transferred through the form and across the pole to the lower right corner of the form.
While the form handler is holding this pressure, the shoveler pitches in a two shovels of snow into the previous block and the bottom back corner of the form.
The form handler then packs the snow into the corner on the inside of the form with one push directly into the corner created by the form, the previous block and the floor or layer below.
This push shouldn’t break the other blocks, but should move the inside form about 1/8 or 1/4 inch towards the inside man.
After the first initial push, the next push should be towards the outside back corner of the form and should spread the form about 1/2 inch.
Depending greatly on snow conditions, the form may want to pop back in as the snow isn't strong enough to hold the pressure of the expanded form. If the form is popping back together, the packer should hold the pressure on the last push in the outside corner while the shoveler places another shovel full of snow over the packers hand.
This will hold the form in the expanded position which puts the form in tension making it much more rigid.
After the form is under tension like this, a few more light pushes and the snow is packed. It is important that subsequent pushes, after the first two, don’t move the form or fracture the snow.
During this process, continue to hold the pressure on the top left corner of the form. After the form is preloaded with pressure, you can release the pressure on the top left corner. You will only need to hold a slight pressure after this to steady the form.
Pulling on the form closes most gaps that occur on the Inner Panel where snow could leak out and makes it so the gap is on the Outer Panel where the shoveler can place his arm to block snow from leaking out. This also makes the inside wall of the igloo smooth so you don't have projections of snow that will drip when the igloo warms up.
When you do have gaps, put your arm or hand over the area and gently fill the gap with snow, applying a slight pressure.
After completing the preloading of the form, the shoveler continues to pitch snow into the back corner and the packer slides his hand moving the first couple shovels of snow to the front of the form while packing it.
After the bottom of the form is packed, continue packing each shovel full of snow as it is pitched into the form but build out from the corner at an angle so you are gaining support from the previous block as well as the lower block.
One thing to point out is that it is a push and not a thump when packing the snow. When you have pushed hard enough, you will feel a “lock up” happen about the same time the form spreads a tiny bit.
If you push too hard, the previous layer or packed shovel full will give way and the entire block will be fractured.
After filling and packing the block correctly, you can move the form immediately.
