Bringing home a new to me G0752Z

[WobblyHand]

More or less have a plan now, and a pile of assorted lumber. Have material for the ramps, and landing extension. The landing extension will have room to set the whole lathe down at 31" above the floor. This is conveniently within an inch of the lathe stand height. Been waiting for a break in the weather to do the woodwork, as I have to do the large stuff outside. Unfortunately there's a nor'easter right now, but, maybe I can sneak in an hour between downpours.

Have a question about the height of the anchors across the doorways. Is it better to have them down lower, or higher? My buddy says it is better to have them up high near the top of the door. This makes me uneasy, but I can't put my finger on why. I was thinking the anchors should be high enough for the lathe to go under but low enough to step over. Higher would be more convenient, but would require more lumber. Is it stronger or better to go higher in the doorway, up near the head jam?

 

[woodchucker]

@WobblyHand I don't know what you are designing. Or what you are doing really. So hard to answer.

I can say that you want to attach to multiple points on the machine, low and high.. if your machine is top heavy, than you need to lower the cg, by removing the weight up top, or adding weight to the bottom. Out riggers also help... so if you have walls going down the stairs attach 2x4s to the top with wheels on the ends to keep the machine from going over...

But without seeing what you are doing, I can't understand what you are talking about for anchor points..

 

[WobblyHand]

@WobblyHand I don't know what you are designing. Or what you are doing really. So hard to answer.

I can say that you want to attach to multiple points on the machine, low and high.. if your machine is top heavy, than you need to lower the cg, by removing the weight up top, or adding weight to the bottom. Out riggers also help... so if you have walls going down the stairs attach 2x4s to the top with wheels on the ends to keep the machine from going over...

But without seeing what you are doing, I can't understand what you are talking about for anchor points..

My apologies. Seemed to split the thread, my bad. Basement_entrance.pdf shows the house doorways. Idea was to have a braced 4x4 across main house entrance and a 4x4 across the external doorway. Use an electric winch (attached to exterior doorway) going through a snatch block (which is attached to the 4x4 across the main house entryway). Shamelessly attaching @Flyinfool's markup of my drawing. This is a birdseye view, looking from the ceiling down. It does not show height.

My question is not about the load. It is "how high in Z should the brown bar be? " If I attach an electric winch across the external doorway, how high in Z should it be? Obviously the red cable has to be above the top step and never rub on anything. The blue circle is a snatch block.

The temporary landing (green steps in sideview_basement_stairs) is for my convenience to have the lathe at nearly the same height as the lathe stand. The lathe stand has wheels so then my buddy and I can move it to the right place.

Hope this is a little clearer. If not, please ask, and I will try to explain it better.

 

[woodchucker]

I think you have to realize that this is risky doing a side pull.
you can't just use a lag bolt. I would do a through bolt of a set of studs, not a single stud. That way you are assured it won't pull out.
As for the question, this is where I bail out. I have too little info. Only you can determine whether your structure, process, etc will work.
the top and bottom not being equal add a level of complexity, since they are not the same rate / angle as the others.
I realize you are talking an old house 1875, so that adds other factors in.

As I said in mine, I added supports under my stairs to aid in taking the load. I didn't like only having a landing header attachment. My stairs flexed too much.

All these issues make me realize I could give you bad information. I presented the idea, but the engineering will have to come from you, and your friend... sorry... but ultimately you are responsible for knowing about things I can't know about.

 

[WobblyHand]

I think you have to realize that this is risky doing a side pull.
you can't just use a lag bolt. I would do a through bolt of a set of studs, not a single stud. That way you are assured it won't pull out.
As for the question, this is where I bail out. I have too little info. Only you can determine whether your structure, process, etc will work.
the top and bottom not being equal add a level of complexity, since they are not the same rate / angle as the others.
I realize you are talking an old house 1875, so that adds other factors in.

As I said in mine, I added supports under my stairs to aid in taking the load. I didn't like only having a landing header attachment. My stairs flexed too much.

All these issues make me realize I could give you bad information. I presented the idea, but the engineering will have to come from you, and your friend... sorry... but ultimately you are responsible for knowing about things I can't know about.

Understood. Not sure where you got the idea to use a lag bolt, nor where it would go. My anchors would be 4x4 beams across the doorways. The left anchor would have a through 1/2" eye bolt rated for 2100 lbs vertical lift. (With big washers as well.) The winch would be bolted to the other 4x4 (or 6x6).

Neither you nor I know exactly how the house was built. Neither of us has the plans. My basement stairs seem to be adequately reinforced. They are not an issue. I'm only trying to get a 300 lb stripped lathe down the stairs. With the angles I have on the chain and cable being roughly equal (56 and 52 degrees) the load on the doorways should be reasonably split, I think. If you think otherwise, please correct me - that's why I am posting.

I suppose one approach would be to maintain the downstairs slope for the cable. By my CAD dwg (based on measurements) the slope of the steps is 44 degrees. As a very good approximation, that is a slope of 1. I can then set up the cable to roughly continue at this slope, but, I don't think it is truly necessary. Again, if anyone thinks otherwise, please let me know, gently or otherwise.

To be honest, I was trying to get third and fourth opinions. Haven't done something like this before, and am therefore proceeding perhaps too cautiously. At the moment, I have no way of gauging my buddy's construction knowledge. Yes, I know he's done lots of stuff, but I have no idea how close to the edge he's been.

Anyways, here is a slightly more filled in drawing. The cable is centered in the doorway. I may eliminate the chain and use steel cable, to reduce the weight. Think the snatch block should be a little further away from the opening, but there's not a lot of room to work with.

 

[Flyinfool]

Some thoughts.
1. Move the winch more to the right so you have approximately a 75/25% split. This will put a more equal load on both sides of the door frame.
2. The snatch block will not stay where you have drawn it. It will swing more to the right. The angle of the snatch block line will approximately bisect the angle of the red line.
3. The eye bolt in the brown 4x4 needs to be either a forged or have the end welded closed. The bent ones can open under load. The load ratings are for a straight pull, it will be significantly derated for your side pull.
4. For the 4x4 in the Main House, I would add the extra piece of wood so that it is on 3 sides of the column near the steps. since the screw eye is a bit out from the beam there is the possibility of the stair side of that beam kicking out toward the main house.

 

[WobblyHand]

Some thoughts.
1. Move the winch more to the right so you have approximately a 75/25% split. This will put a more equal load on both sides of the door frame.
2. The snatch block will not stay where you have drawn it. It will swing more to the right. The angle of the snatch block line will approximately bisect the angle of the red line.
3. The eye bolt in the brown 4x4 needs to be either a forged or have the end welded closed. The bent ones can open under load. The load ratings are for a straight pull, it will be significantly derated for your side pull.

I've decided to not use the snatch block, nor the winch. Instead I will mount chain in the forged eye bolt to the left and use another forged eye bolt where the winch was. Good idea to move the winch/eye bolt over to be more offset in the exterior doorway. Will then put in a carabiner in the chain so the carabiner is centered in the basement doorway. Will then use a come-along to lower the load.

I don't own an electric winch, and the only affordable 120V winch that I can buy is from Harbor Freight. The cable diameter is 5/32" (4mm) which I do not find comforting. The winch is claimed to have 1500 lb capacity, but it uses 422 lb safe working load cable. I'd rather spend the $165 winch cost on lathe tooling.

I saw the bent eye bolts at Tractor Supply and thought to myself, umm, I will take a hard pass on them. Decided to use a 1/2" forged eye bolt for the derating. Should be strong enough even off axis.

One thing that I need to watchout for is stuff digging into the floor. Plan to put down 3/4" plywood (maybe two layers) to protect the tile floor and a guard on the lip of the basement stairs. My better half reminded me we don't even have 1 whole spare tile left, so I'd better not crack one! She also reminded me that tile pattern is no longer available.

Do you have any recommendations for the Z height of the 4x4's? Is floor level desirable, or should they be up off the floor on a pedestal of some sort?

 

[rabler]

Pro’s and con’s on 4x4 height:
1/2 way up maximizes the bending stress on the wall studs but shares the shearing forces between top and bottom nails. Nearer the bottom reduces the bending stress but puts all the shear on the lower set of nails.

Lower does reduce the angle to the lathe to more near horizontal, which means less of the lathe weight is born by any of the rigging.

 

[WobblyHand]

It's a question of, "how strong are the toe nails holding vs how strong are the studs?" For the moment, I am betting on the toe nailing being stronger. If the nails are anything like what I pulled out of the stairs, the toe nailing will be very strong. Nice, old fashioned, beefy, long cut nails.

Lower 4x4's are easier to deal with and requires less materials. Bracing is minimal. (Can't fall down, because it's already on the floor!) Considering that the pallet was pulled onto the porch using the bottom of the exterior doorway alone (and nothing moved, groaned, or complained,) and now the load would be shared with the other doorway, I think it will be ok to use 4x4's laying on the floor. Or at least that's the plan for now.

 

[Flyinfool]

I would keep the rigging on the floor and use a roller bar or slide bar on the top corner of the step.