Shopsmith Forums

rpd wrote:Is 2x6 not overkill?
I would think 2x4 would be more than adequate to hold the weight.

You might be right but I really don't know whether 2x4s would be strong enough at 10'6" so I erred on the side of being conservative and thought I'd use 2x6s. If any of our engineer types would sanction 2x4s, that would be great.

algale wrote:

rpd wrote:Is 2x6 not overkill?
I would think 2x4 would be more than adequate to hold the weight.

You might be right but I really don't know whether 2x4s would be strong enough at 10'6" so I erred on the side of being conservative and thought I'd use 2x6s. If any of our engineer types would sanction 2x4s, that would be great.

I essentially agree on 2x4, but make sure it is selected for use as intended. Most 2x4 are intended for stud use(vertical loads along the length). Small/relatively knot free is needed.

JPG wrote:

algale wrote:

rpd wrote:Is 2x6 not overkill?
I would think 2x4 would be more than adequate to hold the weight.

You might be right but I really don't know whether 2x4s would be strong enough at 10'6" so I erred on the side of being conservative and thought I'd use 2x6s. If any of our engineer types would sanction 2x4s, that would be great.

I essentially agree on 2x4, but make sure it is selected for use as intended. Most 2x4 are intended for stud use(vertical loads along the length). Small/relatively knot free is needed.

The Sagulator http://www.woodbin.com/calcs/sagulator/ suggest it would work (assuming pine is the material).

And if there are two supports the load on each would only be 32 .5 lb.

rpd wrote:And if there are two supports the load on each would only be 32 .5 lb.

Whoops! This is why I like to ask the Forum! Yes, there are two legs (supports). But there is also one cross brace which adds weight.

Still, 2x4 construction is looking feasible!

Rather than the dowel arrangement, I am thinking now of a sled arrangement for ASBTN to ride on; a couple of pieces of 1/2 inch ply on either side of the 2x4s, with provision for a couple of skateboard wheels riding the 2x4s. A cross member joins these two sleds and the entire sled assebly is pulled via another pulley allowing ASBTN to be pulled up to the top end of the legs, getting it all the way over the stairwell and out of the way of lights, etc, before the legs are raised by the original pulley set up.

algale wrote:

rpd wrote:And if there are two supports the load on each would only be 32 .5 lb.

Whoops! This is why I like to ask the Forum! Yes, there are two legs (supports). But there is also one cross brace which adds weight.

Still, 2x4 construction is looking feasible!

Rather than the dowel arrangement, I am thinking now of a sled arrangement for ASBTN to ride on; a couple of pieces of 1/2 inch ply on either side of the 2x4s, with provision for a couple of skateboard wheels riding the 2x4s. A cross member joins these two sleds and the entire sled assebly is pulled via another pulley allowing ASBTN to be pulled up to the top end of the legs, getting it all the way over the stairwell and out of the way of lights, etc, before the legs are raised by the original pulley set up.

I like your rolling sled concept. The only issue that I see with it is that the "wheelbase" will be very short in comparison with the width, which could lead to the sled mis-tracking and binding on the runners (if the C.G. of the load is not perfectly aligned with the rope attachment point). This issue could be avoided by using a rope and pulley at each end of the sled, with both ropes pulled simultaneously (and presumably tied together at the pulling end) so that both ends of the sled move in sync. Just like a window blind.

BuckeyeDennis wrote:

algale wrote:

rpd wrote:And if there are two supports the load on each would only be 32 .5 lb.

Whoops! This is why I like to ask the Forum! Yes, there are two legs (supports). But there is also one cross brace which adds weight.

Still, 2x4 construction is looking feasible!

Rather than the dowel arrangement, I am thinking now of a sled arrangement for ASBTN to ride on; a couple of pieces of 1/2 inch ply on either side of the 2x4s, with provision for a couple of skateboard wheels riding the 2x4s. A cross member joins these two sleds and the entire sled assebly is pulled via another pulley allowing ASBTN to be pulled up to the top end of the legs, getting it all the way over the stairwell and out of the way of lights, etc, before the legs are raised by the original pulley set up.

I like your rolling sled concept. The only issue that I see with it is that the "wheelbase" will be very short in comparison with the width, which could lead to the sled mis-tracking and binding on the runners (if the C.G. of the load is not perfectly aligned with the rope attachment point). This issue could be avoided by using a rope and pulley at each end of the sled, with both ropes pulled simultaneously (and presumably tied together at the pulling end) so that both ends of the sled move in sync. Just like a window blind.

Hi Dennis, thanks for the tip. Can you clarify what you mean by "at each end of the sled"? If you imagine the 2x4 legs of the lift in the down position (touching the floor) and standing directly in front of it with the sled at or near the floor, are you talking about pulleys on the left and right sides of the sled (I think that's what you mean) or at the leading/trailing edges of the sled?

algale wrote:
Hi Dennis, thanks for the tip. Can you clarify what you mean by "at each end of the sled"? If you imagine the 2x4 legs of the lift in the down position (touching the floor) and standing directly in front of it with the sled at or near the floor, are you talking about pulleys on the left and right sides of the sled (I think that's what you mean) or at the leading/trailing edges of the sled?

Yes, the left and right sides. That way, each side of the sled has to roll up the legs (really "trolley rails", as you are using them) at the same rate, and thus the sled can't twist and mis-track/bind on the rails.

I don't know if this is at all helpful, but don't limit yourself to one hoisting rope. I've got my kayak hanging from two independent pulley systems, each of which allows me to lower one end of the kayak a few inches at a time. It also means I'm lifting only 1/2 the weight at a time.

BuckeyeDennis wrote:

algale wrote:
Hi Dennis, thanks for the tip. Can you clarify what you mean by "at each end of the sled"? If you imagine the 2x4 legs of the lift in the down position (touching the floor) and standing directly in front of it with the sled at or near the floor, are you talking about pulleys on the left and right sides of the sled (I think that's what you mean) or at the leading/trailing edges of the sled?

Yes, the left and right sides. That way, each side of the sled has to roll up the legs (really "trolley rails", as you are using them) at the same rate, and thus the sled can't twist and mis-track/bind on the rails.

Add side rails to the 2x4 so the wheels will not slip off the edge. Orrr add a rabbet.