PE/XLPE (Polyethylene)

Polyethylene is a type of Polyolefin. PE/XLPE refers to Polyethylene (PE) and Cross-linked Polyethylene (XLPE), two types of plastic materials often used in electrical cables and other applications. PE is a thermoplastic, while XLPE is a thermosetting polymer, achieved by cross-linking the polyethylene molecules.

PE will typically have larger cells that are easy to see with the naked eye and will have a rougher texture on both cut and skinned faces. It is generally softer, more pliable, and less durable than XLPE of the same density, but these are not always the case depending on the type of XLPE. The cross-linking process significantly enhances XLPE's properties, particularly its resistance to heat, mechanical stress, and environmental factors. The resulting cells are usually so small that even cut surfaces can appear smooth.

2.2# PE

Good foam, but not great for all around use. Primarily useful for shields, but still works about as good as blue foam for striking surface on weapons. Pommels and crosspieces *can* be made entirely out of this, but is best for striking surface and to make the impact areas of crosspieces softer; due to the high level of compression, pommels made of 2lb foam will often fail sooner than pommels made with 4lb foam.

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2# XLPE

A higher quality, more durable, and all-around-upgrade to "standard" Closed-Cell Polyethelene Sheets and Camp Pads. It has better impact damping than the non-cross-linked forms and holds its shape better while compressing, leading to less twisting. It also resists shearing and tearing better than non-cross-linked polyethelene, which helps it last much longer before wearing out. It is my go-to for haft padding, and has some of the best compression recovery of any foam listed on this wiki; I have had multiple weapons with failing divots on their hafts from getting pinched in transport "heal" themselves when left alone for a week.

The only downside is that it is firmer, which means that it is not great for striking surfaces. I have had success using a 1/4" layer of this foam as a skin on 2.6-2.75" diameter Volara/Duratube fries to further cushion striking surface on large polearms. I also use it around my biscuits and under my stab tips, and have found that the small volume and decreased thickness make the increased stiffness moot, while providing a more-stable base for the stab tip.

Volara 2A (2#)

Volara foam is a closed-cell, cross-linked polyethylene foam known for its smooth, pliable, and non-abrasive surface, making it suitable for a variety of applications. It's often used for lining boxes, display cases, and drawers, as well as for padding, cushioning, and creating gaskets. Tends to not get as stiff as Minicel L200 when cold, and also resists surface tears better on skinned faces.

Can be heat bonded (always wear appropriate PPE) and used to make tube fries that are comparable in weight and performance to modern "Duratube" sold by various vendors. The 3/8" thickness is particularly suited to doing this efficiently, only requiring 4 bonded layers to make a half-tube without needing to shave off waste foam.

It would be somewhat wasteful to use this foam for anything but the striking surfaces of a weapon. Generally sold in thinner sheets, it can be purchased in sheets up to 1/2" thick. If you can find a source for it, there is a product line called "Volara Block" that is sold in 4" thick sheets.

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Minicel L200 (2#)

A much more fine-celled foam that is both softer and has higher durability than 'standard' cross linked polyethylene. It would be a waste to use this foam for anything other than striking surface or stab tip foundation.Sources

4# XLPE

You aren't going to find a better-rounded and easy-to-source foam to handle being a pommel, the structural foam for a guard/crosspiece, or for the innermost layer of a box-blade build. Foam of this weight should not be used for striking surface. When using foam of this weight as part of the foundation of a stab tip, it should not extend out to the striking surface; biscuits don't need to be larger than 1.25" in diameter, leave at least a 0.75" buffer of striking foam around it.

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6# XLPE

Very stiff, very durable, very dense. Overkill for almost any use other than for providing structure for guards as an internal "core" and for acting as padding for handles/facilitating carving custom handle profiles.

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