Chlorine bleach
Pros:
- Strongly bleaches all types of wood
- Inexpensive
- Readily available
- Kills mildew
Cons:
- Chlorine gas can be released if chlorine bleach is mixed with other household chemicals, such as ammonia.
- Chlorine gas can be hazardous or fatal
- Kills plants, especially new growth
- Can over-oxidize wood cell walls and degrade them
- Very corrosive to metal fasteners ( nails and screws)
- Can affect adhesion of coatings if not completely rinsed from the logs surface
Oxalic Acid
Pros:
- Particularly good at removing tannin stains
- It is the only cleaning product of choice for redwood - other type cleaners will discolor redwood
- It is the best product for removing rust stains
Cons:
- Does not kill mildew
- It is a poison & must be handled very carefully
It must be thoroughly rinsed from wood that will be finished with water-based coatings or unsightly whitish blemishes may appear beneath the coating ( or other negative effects can occur)
Sodium Per Carbonate (Oxygen Bleach)
Pros:
- The most environmentally friendly bleach/cleaner
- The safest bleach/cleaner to use (but it can irritate the eyes)
- It disassociates into hydrogen peroxide, soda ash & water that's all
- Does not aggressively corrode metal fasteners
- If not completely rinsed from the wood, little affect on subsequent coatings is likely
- Kills mildew
- Strongly bleaches all types of wood (except for un-aged redwood)
Cons:
- Must not be used on un-aged redwood (it turns it almost black in color)
- More expensive than other cleaners/bleaches
- The residual soda as can appear as whitish patches underneath a stain or lacquer if not well rinsed
Trisodium Phosphate
Pros:
- Readily available
- Inexpensive
Cons:
- No bleaching action
All of these products can be purchased on our I-Wood-Care online store under cleaners.