Design - Joining Techniques Flashcards
what is the difference between a temporary joint and a permanent joint?
Temporary joints can be removed easily (such as a screw, nuts and bolts and knock down joints)
Permanent joints cannot be removed without damage to the product (eg. glue, rivets, welding, wood joints)
What types of wood joints are there?
Butt joint- weak joint but quick an easy
Lapp joint - stronger than butt joint due to higher surface area
Dowel (connected with wooden pegs)
Mortise and Gauge - Fits into cut hole
Finger/ dovetail joints - interlocking strong joints
What is a pop-rivet?
The joining of two thin materials using a rivet gun.
What are the 3 types of heating joints?
Soldering
Brazing
Welding
What is soldering?
Melting alloy with higher melting point to join other materials
FLUX is often used before connecting to prevent oxidation
What is brazing?
Similar to soldering however using higher temperatures
What is welding?
Strongest heating joint where edges are melted to connect to each other
Any gaps are filed with filler
What are 3 examples of adhesives?
PVA glue
Epoxy Resin
Liquid Solvent Cement
What are the properties of PVA Glue?
- Not fully waterproof
- Flexible
- Does not emitt odours
- Joins Wood, vinyl or paper
- Takes 24hrs to fully dry
- Turns clear when dry
What are the properties of EPOXY RESIN?
- Strong
- Low shrinkage
- Low cost and toxicity
- Works well for plastics , aluminium and glass
- 24 hrs to dry
- Very strong
- Requires the mix of two different parts to a 1:1 ratio to be activated
What are the properties of liquid solvent cement?
- highly flammable
- Can be toxic if ingested
- Brush to apply
- Dries very quickly (2hrs)
- Good for sticking plastics together
- Strong bond