🌞 New Stock Frame Design 🌞

This took about two hours to throw together. I bet it would be less if there were instructions so I didn’t have to reference the CAD model for all of the lengths. The through bolts were really easy.

It’s really solid with not much in the way of a tendency to rack. I could certainly push it over if I tried, but it’s pretty stable.

@dlang I think you might be right that I need 3 2x4s as spacers. I know we’ve worked this all out before and I think I just forgot. I will review in the morning when I am fresh.

Let’s compare notes and pictures of the finished versions and talk about what worked and didn’t work about each.

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I couldn’t agree more! I’m not sure I’m a good enough woodworker to build a lot of these designs.

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@bar What about your bottom horizontal 10’ 2x4 that’s right above your leg supports. It’s in your CAD image but not your final design? That should help a little.

I believe you are right to highlight this. I would expect high forces to cause deflections. This is why I’m seeking maximum frame stiffness in the directions of those forces.

As I said, I’m not worried about it standing when the wood is new, it’s as things age and loosen up that there will be grief.

look at any fence/gate that’s bolted together and hasn’t been touched for years and how they sag

.

One change I think you should adapt from ‘my’ design is the bottom crossbeam and wings as separate pieces. That gives you a place that you can mount tabs to support the workpiece that you don’t have with a solid beam behind the legs.

As for the skill needed to build the design. That’s why the main design we have been working on only uses square cuts and why we have the detailed written directions and are doing pictures to go through each step. It’s also why the assembly instruction don’t require any measuring, just using other parts as spacers (including centering the top beam)

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well, you can drill pilot holes for screws as well, and they go a lot faster
than the large bolt holes.

But if you were talking about replacing screws with bolts on a 1-1 or even 2-1
(bolts instead of screws diagonal from each other), I wouldn’t be fussing as
much.

But we are replacing 4 screws with a single bolt and counting on the friction to
hold things together forever.

That’s not nearly as good.

We would be better off with no screws and just glue and clamps compared to a
single bolt.

A single bolt is sufficient to hold each corner of the triangles that are the basis of Bar’s design. The other bolts that could pivot are prevented from doing so by the plywood portion of the frame. Pretty simple.

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the claim is that the plywood is not structural. So it should not be counted on
preventing anything from pivoting.

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This didn’t start as a long post… I tried to whittle it down to the salient points. Everything here is meant with the greatest of respect to all.

From a commercial product standpoint (we all want @bar to stay in business), the more accessible a product is the more likely someone is willing to invest in the product. My opinion is that @bar’s current design is clearly less daunting than any that have been offered. However (constructive criticism) I know it would not work in my shed. As I have done with the current stock design, I would end up adding a top brace, bottom brace and at least one vertical brace. I have to have something to clamp to in order to make the workpiece flat.

With respect to bolts vs. screws and glue, glue is an immovable joint but I personally think it’s easier to assemble using bolts and bolts that loosen over time can be tightened up. @dlang has come up with a clever set of steps to minimize the difficulty in assembling. The downside to glue and screws is that the joints are permanent and there’s no disassembly/collapsing/rebuilding allowed.

With respect to top beam, @bar’s design causes issues with someone wanting to use unistrut though technically, you could mount the unistrut to the top of the 2x4x10 top beam.

So with all that said, perhaps we give the builder a couple options on the website at the same prominence as the stock design. Let the builder choose what they want or what they are comfortable building:

  • Stock Design (using hardware provided if they just want a basic design and will check on the tightening of bolts over time)
  • Option 1: Permanent Frame Design (using screws/glue with ability to use a unistrut-only top beam)
  • Option 2: Collapsible Design or an All-Unistrut Design

Too many options will lead to decision paralysis… we just need them to feel comfortable they can build something and purchase the kit. Considering the time it takes to get the kit after purchase :wink: they’ll have plenty of time to study the options and make a decision on which frame they want to build. Edit: I really hope that comes across as humorous

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first off, in re-reading my posts yesterday, i realize there was a tinge of 'but this is going to throw away all the work that I spent all day sunday doing" in my initial reaction, apologies for that.

I created the assembly steps to do everything the default way and then listed options below, I’m going to move the description of the options up to the top, and then flag the differences in the assembly steps.

looking at the two with fresh eyes:

image

image

  1. the rear crossmember is not needed if you build the machine and never move it. It’s needed if the rear legs are going to get knocked around (either because you have to move it as-is or you put wheels on it) or if you are going to make them able to fold.

    I’ll flag that as optional

  2. the verticals and top crossmember are only needed if you are not going to have a sheet of plywood there all the time (or if you have problems with the plywood warping the way @madgrizzle does)

I’ll flag these as optional

The remaining significant differences in basic shape are:

  1. solid bottom beam vs wings and center bottom crossmember

    I think the bottom crossmember is very important.

    • I’ve had 4x8 sheets of maple plywood warp over time from only being supported by their ends.
    • The bottom crossmember being flush with the bottom of the workpiece means that we can attach tabs to the bottom of the crossmember to support material that’s not wide enough to rest on the kickers
  2. diagonal braces
    This gets into the discussion we were having yesterday about the long-term stability of the machine. If you are going to (semi)permanently attach a sheet of plywood to the front, they aren’t needed long term (but it’s useful to add at least one of them to keep everything square until the plywood is attached.
    The idea that the plywood isn’t part of the frame, but is instead just a wasteboard (which could be foam instead of plywood) is something I find attractive, and it’s really easy to attach them

  3. top beam mount
    This is what we were hashing out yesterday, let’s leave that as a separate discussion

The result now looks like this:
minimal%20maslow

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@bar, what are the lumber lengths you used for your frame? it looks like you have the kickers a bit higher off the ground than the design we’ve been working on, and it looks like your legs are a bit taller.

I made the rear legs 5’ long so that you could get both of them out of a single 10’ stick.
I have the top of the kickers 10.5" up the front legs,
I have the front legs 6’ (72") and the resulting machine is really pushing the max height to fit through a door (80" tall and 28" deep)

moving the kickers up will mean needing more height and the result won’t fit through a door.

making the legs longer will need more wood

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one note on the top crossmember, without something of a fixed length at the top, you can’t square up the mcahine. The top bar could be that thing, but then you have to square the machine after you stand it up, and that’s areal pain compared to being able to square it while it’s (fairly) flat on the ground because when things are standing up, they don’t stay where you put them, and there’s no easy way to anchor things (put a weight next to the frame to hold it in place)

I had a ‘wings’ setup on my frame for a while, they were a source of trouble because they were insecure due to the leverage concentrated on the small attachment point. I settled on a 10’ bottom beam and find it more secure.

A beam across the back legs doesn’t add as much stability as bracing them from the aforesaid bottom beam would.

Bar is opposed to having a bar across the front.

did you just attach the wings to the legs? In this I extend them a bit and also attach them to the crossmember, which adds quite a bit to their strength

I refer to his diagrams which show the lower bar.

The ‘wing tip’ is still a weak connection, narrow and with the forces on the fasteners in their weaker direction.

I agree it’s not as strong as a solid piece of wood, but is this bad enough to have a full length beam and a crossmember in front of it and a couple inches down?

Just to add fuel to the fire… I posted this in another thread that devolved into discussing what to do with the crate of leftover quadrilateral brackets…

Drawing1

Hey, I got a new badge ‘First Onebox’ for that autogenerated link quotebox. Not sure how I did it, but I’ll take it.

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I like using those brackets a lot more than drilling through the leg

Retrofitters already have a pair.

Haha we have a bunch of extra brackets, but not enough to send them to everyone :roll_eyes:

I just don’t like the sled running into it giving me little bumps in my lower cuts. I’m game for having a front cross brace as long as we can put it somewhere the sled won’t hit it

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