Uncommon Building Materials

 

 

 

sources: one, two, three, four, five, six, seven

 

by Jonica Klein

Cabinet Core Materials

As a designer at a fixture company, I should have some understanding of what goes in to making a cabinet--you start with some type of middle material and put a laminate on it, right? Well, yes, but while I never knew the specifics, I had a feeling there is actually a little more to it. So when my boss approached me about putting together a list of cabinet core materials, I thought, "Simple! Two, three choices max?" Wrong! There are so many to chose from, and each option has its pros and cons. Pick the right one and you have a sturdy, well made cabinet that will stand the test of time. Pick the wrong one and you may be replacing your cabinets a little more often than you had anticipated!

While you might not get the opportunity to put this information to use on a regular basis, if you play any type of role in specifying, purchasing, or installing cabinetry it is helpful to have a basic understanding of how the product is constructed.

Read on for a run-down of core materials...

1. Plywood

•  Strong
• Doesn't pose the cracking, warping or shrinking threat of solid wood
• Can be manufactured in very large sheets
• Two types:
• Hardwood Plywood
• Generally higher quality
• Emits gas and formaldehyde from adhesive used in construction
• Softwood Plywood

2. Combination Core

•  Consistent flatness
• Good screw-hold ability
• Lighter than MDF or particleboard core

3. Lumber Core

• Good bending strength
• Good screw-hold ability
• Excellent matching properties
• Edges can be shaped and matched to finished surfaces without filing
• Good bounce back, making it a great choice for long or wide shelves in cabinets and closets
• Good choice when routed edge treatments are necessary and the edges cannot be concealed
  CONS
• This is the most expensive core to manufacture, meaning finding a supplier may be difficult
• Only the highest grade lumber core should be considered as there is a severe drop off in the consistency in lesser grades
• Most grades machine poorly
• Substantial voids are often present

4. MDF

• Very smooth surface
• Strong
• Not prone to warping
• Typically consistent from batch to batch
• Typically free of voids and blisters, which results in better veneer consistency and bond, leading to less chipping during crosscut operation
• Easy to machine and cut edges are excellent for glue adhesion
• Good for use in humid climates or rooms
• Great screw-hold ability when used with MDF-specific screws
• Less expensive than plywood
  CONS
• Extremely sensitive to heat and may experience bubbling, blistering, discoloration and peeling as the surface becomes damaged
• MDF cabinets usually can't be repaired and generally need replaced more often.
• More expensive than particleboard
• More dense than particle board or plywood
• Subject to water damage unless properly sealed with melamine, laminate, or other similar water resistant material.

5. Particleboard

• Least expensive of all core types
• Lighter than MDF
• Great use of a waste product that would otherwise be discarded
• More economical than plywood
• Its uniform thickness, smoothness, surface integrity, ease of layup, and ability to stay flat make it an ideal core material
  CONS
• Heavier than plywood, but not as strong
• Edges splinter easily and aren't as strong as MDF
• Does not have the screw-hold ability of other cores, however it does increase significantly with the use of particle board specific screws
• Its use can indicate inferior construction and materials when used in the construction of furniture or cabinets
• Tends to swell and separate, even with brief moisture contact
• The high glue content found in the product quickly dulls the knives and blades on processing machinery and tools
• Emits gas and formaldehyde from adhesive

6. Hardwood

• Expands and contracts as it interacts with moisture in the air

7. Veneer Core

• Moderate price
• High strength to weight ratio
• Provides dimensional stability and good strength both along and across the panel
• Excellent bending strength and screw-hold ability
• Lighter in weight than other core types
  CONS
• Voids in the core and face are common
• Not always consistent in thickness from sheet to sheet, or within the same sheet
• The pre-veneered surface is coarser and does not accept veneer as well, resulting in excessive chipping and tearout during the machining process
• During cutting, you will always be ripping some layers and crosscutting others, which makes cutting more difficult with a greater tendency to burn
• Saw-cut edges are not as clean and smooth as other core types--does not take edge glue well
• Inconsistencies in the pre-veneered surface can result in thin spots in the veneer

8. Fir Core

• Very resilient to weather while being quite stable
• Great screw-hold ability
• Relative softness of the layers means that any inconsistencies in the product will even out during compression

9. Poplar Core

• Heavier and harder than fir
• Very stable
  CONS
• Lacks weather resistence
• Will not compress, making voids and knots more likely to telegraph through the surface veneer
• Poplar that is not dried properly is more prone to delamination

10. Aspen Core

• Similar properties to Fir Core, but less dense, resulting in a lighter sheet
• Soft and will compress nicely giving a consistent face

11. Birch and Maple Core

• High density
• Both species are hard and thin, making for an extremely stable product
• It is very unlikely for a void to be found in these core types
• Good edge strength, making them less prone to splintering than Fir and Poplar
• Relatively attractive cores, making them a great choice when the edges of the final product will be exposed
• Maple has slightly more grain pattern on the surface, allowing for it to be sanded very smooth
  CONS
• Specialty high-end product
• Birch core has a tendency to splinter at the edge of a machined cut
• These are the most expensive cores available

12. Fire-rated Core

• Suitable for a variety of industrial and commercial building applications where stringent building codes and public safety requirements are a factor

13. NAUF Core

• Recommended for applications where the presence of formaldehyde is a concern
• Environmentally-friendly

14. Bamboo Core

• Great for use in tropical or high humidity climates
• Sustainable and environmentally-friendly
• Strong
• Can be made water-resistant
  CONS
• More expensive than MDF

15. Medium and High Density Overlay Plywood Core 

• Lighter than full MDF core
• More stable surface than veneer core plywood