Hi Karma,
can I afford to buy my cases from you?
Sure do look good, well done.
That pic of a countersunk socket head set screw is neither a bolt nor a screw.
A bolt has a shank and the remainder is threaded. The threaded length is generally about 6 diameters but varies with bolt type and manufacturer.
A set screw has thread to within 1.5 pitches of the head.
can I afford to buy my cases from you?
Sure do look good, well done.
That pic of a countersunk socket head set screw is neither a bolt nor a screw.
A bolt has a shank and the remainder is threaded. The threaded length is generally about 6 diameters but varies with bolt type and manufacturer.
A set screw has thread to within 1.5 pitches of the head.
Hi,
I saw and read the link in post 26. I thought at the time that ignoring the nonsense contained therein was better than discussing it and passed on what I thought was more accurate information.
The person that wrote that bolts vs screws forgot that screw can mean a number of things. He mistakenly used his very restricted definition to completely exclude a whole category of fixings. My advice is to ignore post 26 because he either does not know enough or he has a political agenda.
Set screws, although some of us DIYers are calling them machine screws, tend to be over used when bolts are designed to do the job better. eg. when a clamped pair of surfaces are subject to shear the interface should have a dowelled or bolted connection to prevent slip and in the event that friction is not strong enough to carry the shear load then a threaded portion of bolt/set screw should not become the shear load transfer medium. The plain barrel of a bolt or tight fitting dowel is designed to carry the shear better than any thread. However the designer should endeavor to design his fixing arrangement to carry all the working loads by friction alone and not have to resort to load transfer via the plain barrel.
A reminder that when a set screw fixed shear interface slips, then the set screw will bend and induce severe stresses at the thread root. Continued slipping in different directionswill cause the set screw to fail due to fatigue. Similarly the thread form will become deformed due to shear overload of the joint.
I saw and read the link in post 26. I thought at the time that ignoring the nonsense contained therein was better than discussing it and passed on what I thought was more accurate information.
The person that wrote that bolts vs screws forgot that screw can mean a number of things. He mistakenly used his very restricted definition to completely exclude a whole category of fixings. My advice is to ignore post 26 because he either does not know enough or he has a political agenda.
Set screws, although some of us DIYers are calling them machine screws, tend to be over used when bolts are designed to do the job better. eg. when a clamped pair of surfaces are subject to shear the interface should have a dowelled or bolted connection to prevent slip and in the event that friction is not strong enough to carry the shear load then a threaded portion of bolt/set screw should not become the shear load transfer medium. The plain barrel of a bolt or tight fitting dowel is designed to carry the shear better than any thread. However the designer should endeavor to design his fixing arrangement to carry all the working loads by friction alone and not have to resort to load transfer via the plain barrel.
A reminder that when a set screw fixed shear interface slips, then the set screw will bend and induce severe stresses at the thread root. Continued slipping in different directionswill cause the set screw to fail due to fatigue. Similarly the thread form will become deformed due to shear overload of the joint.
Only way to do it right is to use threaded brass or steel insert and glue/screw it to bigger hole.karma said:im using industrial screws to hold the top on my psu. thay fit and i used the right sized bit. what im asking is there anything i can put on the threads to help them turn out better?
any ideas?
Threaded cherry rivets or similar are probably easiest to find, but there are even ones with coarse outside threads specific to woodworking.
Look for something like these: http://www.avdel.textron.com/brochures/threaded_inserts/index.htm
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