Evening All,
I'm trying to figure out how to make a mechanism which will raise and lower a 700mm long c.20mm dia rod or dowel. The rod/dowel will need to stay horizontal and will need to carry a load of c.90kg. My intial idea is as per the sketch attached. The plan would be to use a piece of threaded bar at each end of the rod/dowel, held vertically and turned using winding knobs attached to the top. The threaded bars would pass through a threaded hole near each end of the rod/dowel and as the knobs are turned the rod/dowel would move up and down. The rod/dowel will not be loaded while it is being moved - it will only need to carry the c.90kg once it reaches the desired position.
My question is how do I create the threaded hole at the ends of the rod/dowel. My preference is to use a wooden dowel as that's where my skills lie and I have the most kit. I would consider using a metal rod but that's more outside my comfort zone. Either way it will need to be round. The ideas I have come up with so far are:
1: Use a wooden dowel: Drill vertical holes through the dowel and put in a metal threaded insert. To make this strong enough I will need to go for a dowel sigificantly bigger than 20mm dia. That can be accommodated.
2: Use a metal bar (or tube): Drill a vertical hole then tap a thread. If I use M8 threaded bar, any idea how big a bar/tube I should be looking at to accommodate the required hole/tap?
3: Try to identify a pre-made fitting (maybe a KD fitting?) which has some means of attaching it to the end of wood dowel and a threaded hole perpdendicular to the long axis of the dowel. I'm not really sure what to search for on this and a general Google search of KD fittings etc has come up blank.
Would be grateful to hear anyone's thoughts on the above suggestions or, preferably, come better ideas!
Many thanks
I'm trying to figure out how to make a mechanism which will raise and lower a 700mm long c.20mm dia rod or dowel. The rod/dowel will need to stay horizontal and will need to carry a load of c.90kg. My intial idea is as per the sketch attached. The plan would be to use a piece of threaded bar at each end of the rod/dowel, held vertically and turned using winding knobs attached to the top. The threaded bars would pass through a threaded hole near each end of the rod/dowel and as the knobs are turned the rod/dowel would move up and down. The rod/dowel will not be loaded while it is being moved - it will only need to carry the c.90kg once it reaches the desired position.
My question is how do I create the threaded hole at the ends of the rod/dowel. My preference is to use a wooden dowel as that's where my skills lie and I have the most kit. I would consider using a metal rod but that's more outside my comfort zone. Either way it will need to be round. The ideas I have come up with so far are:
1: Use a wooden dowel: Drill vertical holes through the dowel and put in a metal threaded insert. To make this strong enough I will need to go for a dowel sigificantly bigger than 20mm dia. That can be accommodated.
2: Use a metal bar (or tube): Drill a vertical hole then tap a thread. If I use M8 threaded bar, any idea how big a bar/tube I should be looking at to accommodate the required hole/tap?
3: Try to identify a pre-made fitting (maybe a KD fitting?) which has some means of attaching it to the end of wood dowel and a threaded hole perpdendicular to the long axis of the dowel. I'm not really sure what to search for on this and a general Google search of KD fittings etc has come up blank.
Would be grateful to hear anyone's thoughts on the above suggestions or, preferably, come better ideas!
Many thanks
