Steel Frame & Weldments Pro for Fusion 360 — User Guide

Platform: Windows and macOS. Every version is published as a Windows bundle and a separate macOS bundle with the same commands; pick the platform in the download section of the product page.

Open this guide from the Help (?) button in a Weldments command dialog. Library > Info also links to the online Pro guide, product page and support.

1. Find the tools. Run Weldments from Utilities > Add-Ins. A Weldments tab appears in the Design workspace with four panels: Create (Frame, Member, Gusset, End Cap, Base Plate, Weld Bead), Modify (Notch, Miter, Trim / Extend, V-Notch & Fold, Tab / Slot, Plate Tab / Slot), Fabricate (Cutting List, Stock Optimizer, Plates to DXF, Weld Cost, Frame Check, Frame Studies) and Library (Manage Library, Profile from Sketch, Delete Profile, Info).
2. Sketch the member centerlines. Use sketch lines/arcs, or select model edges. Keep the sketch visible while selecting.
3. Create the main frame first. Use Create > Frame. Select the primary rails/posts as Group 1, choose the profile (standard, family, outer size and wall thickness), then add more groups for braces, diagonals, arcs, or different profiles. Where two groups of different widths meet, set that corner's Corner override to Miter so the cut runs through the real corner.
4. Check the live preview. The preview uses the same temporary BRep trim pipeline as the final build. If a corner looks wrong, fix group order, trim type, or profile orientation before clicking OK.
5. Add plates and joints. Use Gusset for reinforcement plates, End Cap for closed profile ends, Tab / Slot for locating joints between members, base plates and gussets, and Plate Tab / Slot for rows of tabs between plates or any other solid bodies.
6. Export fabrication data. Use Cutting List for the on-screen table, CSV, and PDF cut sheet.

What a Frame group means

Group order and priority

Corner and trim options

Corner override (one corner of this group)

Corner default and Trim type apply to every corner of the group. Use Corner override (this group) when a single corner must differ, instead of splitting the group in two.

1. Expand Corner override (this group). It appears once the group has two or more corners, or one corner shared with another group. A cross marker is drawn at every corner this group takes part in: grey = can be overridden, orange = already has its own style, cyan = the corner being edited.
2. Click a member near the corner you want. The nearest marker turns cyan.
3. Set Corner and Trim type for that corner. Leave either on Use group default to keep the group setting for that one.

A Butt or trim override reaches only this group's members at that corner; members of other groups keep their own group default. A Miter override at a corner shared with another group cuts both members on one plane through the real outer and inner corners of the two sections, so a 60x40 rail and an 80x40 post (same depth, different widths) close with nothing sticking out — the group's own Corner default never mitres across groups. Overrides are saved with the frame, travel with the group when you reorder or delete groups, and are reloaded when you edit the frame.

Edit an existing frame

1. Run Frame.
2. In Edit frame, select any body created by the Frame command. A body from the Member command is not accepted — edit that one with Member.
3. The saved groups, profiles, orientations, and options are loaded, and the centerline sketches are switched back on so their curves can be re-selected.
4. Change the settings and click OK. The frame is updated where it is: it keeps its component, the name you gave it and its place in the timeline and browser. Sketches and joints made on its member faces keep working while those faces still exist — a length or position change keeps them; a new profile size makes new faces, and Frame then names the items to pick again. Adding or removing members rebuilds the frame at the same timeline position with the same name. Clicking OK without changing anything leaves the frame exactly as it was — unless the centerline sketch moved since the build (a changed dimension, a dragged point): Frame notices that, says so in the Edit frame hint, and OK rebuilds the frame from the new sketch with the same profiles and options. That is the way to update a frame after editing its sketch; nothing has to be re-entered.
5. Tab/Slot joints, gussets, and end caps recorded on this frame are un-built with it and re-applied to the rebuilt members automatically. Items you deleted by hand stay deleted. If one cannot be re-applied, Frame lists it after the build — create that item again.

Gusset creates a plate between two support faces. It is intended for reinforcement plates after your members already exist.

End Cap creates plates on selected closed-profile end faces.

Base Plate adds a bolted foot or mounting plate to a member end — the plate every post, table leg and machine frame needs and that you would otherwise sketch by hand. It uses the End Cap machinery: pick planar member end faces, the plate sits flush outside the end, centred on the section with its sides parallel to the section walls, and it is rebuilt automatically after a Frame or Member edit.

Weld Bead detects contact seams between Weldments members and plates, creates supported fillet or surface-cap bead solids, and records a weld schedule. Select specific bodies, one frame or the entire design. Supported round-tube saddle and corner-radius contacts can also create solids; other detected spans remain in the schedule without display geometry. Use Preview seams to distinguish solid-capable seams from counted-only spans before building.

Weld Cost turns the weld schedule into quoting numbers: consumable mass, arc time, labour time and cost per weld and in total — the SolidWorks Weld Bead Properties idea (process, passes, mass, cost, time) with editable shop rates.

Tab / Slot adds a locating tab and a matching slot for tube and plate fabrication. Select the Tab body first, then the Slot body. Supported pairs are member to member, member to base plate, and gusset to member. Use members and planar, constant-thickness plates created by Weldments. Each pick is captured and its highlight cleared; the Tab: / Slot: readout confirms the selected bodies. Click either Select box to replace that body.

The tab body end or gusset edge should meet the receiving face. The command finds the contact from the two bodies; no extra face selection is needed. If a gusset touches two different members, select the member that should receive this slot; run the command again with the other member to create a second joint. If the same pair has more than one possible contact, the command asks you to adjust the parts instead of choosing an arbitrary edge. A buried end, a slot that breaks out of a face or existing opening, or a cut into unintended material is refused.

The preview shows the tab in orange and the slot cut in red. An orange message explains an unsupported or ambiguous joint; the real bodies change only when you click OK. The joint locates parts for assembly and welding; it does not verify joint load capacity.

Each joint is stored as a TabSlot:<n> timeline group and linked to its two parts. Frame or Member edits rebuild the attached plates before replaying their Tab/Slot joints. Replacing a linked Base Plate or Gusset also replays its joints on the replacement part. If the edited parts no longer provide a valid contact, review the reported joint and adjust the geometry before retrying. A TabSlot group you delete by hand stays deleted.

Plate Tab / Slot adds a row of self-fixturing tabs along a plate edge and cuts matching slots in the part that edge sits on, so plasma, laser and waterjet parts locate themselves for welding. It works on any solid body — plates you modelled by hand, imported bodies, gussets, end caps, and frame members as the slotted part — in the root or in any component, moved, rotated or nested. Nothing has to be made by Weldments.

Pick the Tab plates, then the Slot parts they sit on. Each picker takes as many bodies as you like: every place where a tab plate's edge rests flat on a slot part becomes one joint, so four walls and a base are one run. Each pick is captured and its highlight cleared straight away — read the Tab plates / Slot parts lines under the pickers, pick a body again to drop it, pick it in the other picker to change its side, or press Clear picks. The line below reports the joints and tabs you will get, or says why a picked plate joins nothing.

The plate edge must rest flat on a planar face of the slot part; a weld gap of up to 2 mm is bridged by the tab. The plate must stand square on that face — inclined plates are refused. Two plates lying face to face (a lap) have no edge joint and are skipped. A tab always takes the full plate thickness, because it is cut with the plate outline.

Round parts. Two round joints work the same way, on hand-modelled bodies too:

• A round plate edge on a round face of the same axis — a ring or a plate with a hole around a tube (a pot liner and its top ring), or a disc inside a tube. Pick the ring or disc as the Tab plate and the tube as the Slot part. The tabs stand on the edge's tangent and point across the axis, through the tube wall, flush with its far side. A solid bar has no wall to pass through and is refused. A closed ring or disc away from the tube's end can only be fitted when the tube is rolled or split around it; the line under the pickers says so. At the tube's end the slots are open and the part slides on.
• The end of a tube on a flat face — a rolled liner or tube standing on a base plate or a flat ring. Pick the tube as the Tab plate and the plate as the Slot part. Each tab is a piece of the tube wall continued past its end, and each slot the same arc shape with the clearance all round.

A full circle gets its tabs evenly spaced all the way round, with no end margins (Maximum spacing is measured along the circle); a partial ring is treated like a straight edge with its end margins. Tab width is measured across the tab, as on a straight edge. On a small tube the tabs sweep a wider angle at the bore, so fewer are placed when their slots would leave less than 3 mm between them; a tab too wide for the tube is refused with a message.

A slot goes through the first wall only, so a plate tabbed into a tube leaves the far wall untouched. Where an edge hangs past the slot part, only the supported stretch gets tabs; a tab that would land over a hole is skipped and the line under the pickers says so. The preview draws the tabs in orange and the slot cuts in red, and OK builds exactly what the preview showed.

Each joint is grouped in the timeline as PlateTabSlot:<n> and recorded on the document. When a Frame, Member, Gusset or End Cap edit rebuilds a part the joint sits on, the joint is un-built first and re-applied to the rebuilt part automatically; a Frame edit reports any joint it could not re-apply. To change a joint, delete its PlateTabSlot:<n> group (or undo) and run the command again — running it twice on the same edge adds more tabs between the first ones. Deleting the group by hand removes the joint for good. Slots cut into frame members count in the Cutting List like Tab / Slot holes.

Make a run of members from one tube. At each corner the tube is V-notched through every wall except the wall on the outside of the bend (the hinge wall), folded, and the closed V is welded: fewer parts, fewer welds, and corners that come out square.

1. Build the frame as usual with Miter corners (the default between members of one group). A corner between two groups, or one sharper than about 20°, is a butt joint: edit the frame and set it to Miter under Corner override (this group). Keep the frame's Weld gap at 0 and set the gap in V-Notch & Fold instead.
2. Run Modify > V-Notch & Fold and pick the members, joined end to end. They may turn different ways (up at one corner, sideways at the next): each V is cut on the wall that is outside its own bend. The preview shows the folded tube on the members (they are hidden meanwhile), and the dialog lists the flat length and the fold centres.
3. OK adds a component Folded … with the tube as it will be after bending, where the members are. The members are hidden behind it; they stay in the design, so Edit Frame and the other commands keep working on them. The straight tube with its V-notches (the flat pattern) is in the Cutting List: its flat length, a notch table and, in the PDF, a drawing of the notched bar; Export tubes there writes the flat bar as a STEP file or puts it in a new design.

• Closed loop: the loop stays welded at one corner, the start of the member picked first (a red dot in the preview). Both ends of the bar are mitred for that corner.
• Cutting List: the folded members are one row marked (folded), with the flat length and a notch table: the fold centre measured from end 1, the bend, the face the V opens on (A is the face of the first V, B the opposite one, C and D the two between when the folds turn different ways) and the V width. The CSV adds a NOTCH & FOLD section and Stock Optimizer nests the flat length. The list always measures the members as they are now.
• Weld Bead welds only the V at a fold, not the bent wall.
• Edit Frame (pick the folded tube in its Edit frame box) updates the folded tube with the options it was made with; while you edit, the folded tube is hidden behind the preview; a folded part that loses a member is removed. A changed section or path must still satisfy the fold limits. If rebuilding fails, fix or remove that fold before exporting: the Cutting List blocks invalid folds instead of exporting stale geometry. After Trim / Extend, Notch or Miter on its members, run V-Notch & Fold again on the same members. Previously exported files are separate snapshots; export them again after an edit.
• To undo a fold, pick its members and tick Remove the fold: the members are shown again and the folded tube goes.
• Square and rectangular tube fold at any of their flat walls. Only the flat hinge strip is bent; the rounded section corners at its two ends are relieved, leaving exposed arc-shaped end faces. All selected members must use the same section dimensions, wall thickness and material. Angle and channel fold only where the upright leg or the web is on the outside of the bend. Round tube and bar, solid bar, I, H, T and custom sections, and curved members are refused with the reason.

Cutting List reads recognized Weldments members, gussets, end caps and base plates in the active design, and takes flat plates you modelled yourself when you point at them. It lists physical pieces, not selections: a member cut completely through by another part is counted as the separate bars to fabricate.

Stock Optimizer plans which cut-list members come from the stock bars you buy, such as 6000, 6100 or 12000 mm. It reports bars to order, the cutting sequence, waste and reusable offcuts. Parts are separated by profile and material and use their long (stock) length, including mitred ends. The achievable saving depends on the actual piece mix, stock lengths and shop settings.

Plates to DXF writes one flat DXF per unique gusset, end cap and base plate — and per flat plate you modelled yourself — for the laser, plasma or waterjet shop, plus a plates_index.csv with file, quantity, thickness, size, mass and material for the cutting order.

Frame Check screens the stress and deflection of straight frame members under self-weight and the loads you enter, with an Euler buckling reference for compression. After calculation it colours members by stress utilisation. The preview does not leave geometry in the model. Inputs are remembered. Tick Save PDF report or Save CSV to export; with both off, OK closes the check.

Frame Studies in 5 steps

Two commands: use Frame Check to place loads and supports, calculate, and save them as a case. Use Fabricate > Frame Studies to show and compare cases, combine them and compare design versions. A case keeps the loads and supports, not results, and is always calculated on the current frame; a design version keeps a calculated result as it was, to compare frame revisions.

1. Save cases in Frame Check. Place the loads and supports of one situation (for example dead load D), type a case name and click Save loads as case. Repeat for each situation (L, W ...), then click Save / Close.
2. Show a result. Open Frame Studies. In 1. Show a result, choose a case in Item and click Calculate / show: it is calculated on the current frame and drawn in colour.
3. Compare. In 2. Compare, choose All cases and click Compare. Export PDF or Export CSV saves the table.
4. Combine cases. In 3. Combine cases, type a name (e.g. 1.35D+1.5L), add each case with its factor and click Save combination. It joins the Item list: show it, or compare All combinations.
5. Save a version before changing the frame. With a result shown, type a name in 4. Save a version (e.g. Rev A) and click Save this result. After changing profiles or rebuilding the frame, calculate again, save Rev B and compare All versions. Click Save / Close and save the Fusion file to keep everything.

Cases, combinations and versions in detail

Load cases: in Frame Check, enter a name and click Save loads as case to keep the load setup. A new name creates a case; the same name updates it. Apply case restores its selections and settings. In Frame Studies, Calculate / show calculates the chosen case on the current frame, and comparing All cases recalculates every case. Export PDF / CSV saves the comparison shown. Delete removes the chosen case, combination or version. Changing a name does not rerun the solver.

Design versions: calculate, enter a version name and click Save this result (group Save a version in Frame Check, 4. Save a version in Frame Studies). Each version keeps the calculated results, member geometry/sections, materials, supports and loads at that time. Rebuild or change a profile, calculate again and save a new version. In Frame Studies, Calculate / show on a version shows the numbers it saved, and comparing All versions reports nominal beam mass, peak yield utilisation and the largest displacement (sway and support movement included), with changes relative to the first saved version. Old versions are never recalculated. These are overall comparisons; rebuilt members are not automatically paired with deleted members. Beam mass excludes plates, beads and fasteners.

Load combinations: save the source cases in Frame Check. In Frame Studies, open 3. Combine cases, choose a load case and a signed factor, then Add to combination. Repeat for each source; adding a case again replaces its factor, and a zero factor removes its load contribution. Name the combination and Save combination. Choosing a saved combination in Item loads its factors back, to change them; saving under the same name updates it. Every factor multiplies all loads in its source case, including self-weight when enabled. For D + L + H, enable self-weight in D only. Cases must use the same members, supports, materials and deflection limit. Signed forces and moments are combined before solving; stress/deflection maxima are not added. Factors are user-defined, not prescribed by a design code. Check deflection decides whether the combination is judged against the deflection limit: it is on by default when every factor is 1 (a serviceability combination) and off for factored strength combinations, whose deflection is still shown. Deleted case references stop that combination with a message.

Finish with Save / Close (or Save report when export is enabled), then save the Fusion document. Cases, design versions and combinations belong to this design and survive reopening. Cancel discards case additions, updates and deletions made during the command. Missing or ambiguous model references are reported; the add-in does not substitute another member. After rebuilding a frame, reselect affected references and save the case again. Every button explains itself in its tooltip.

Weldments includes a local Model Context Protocol server for approved AI clients. It exposes eight fixed tools: weldments_get_status, weldments_list_profiles, weldments_list_sketch_paths, weldments_get_selection, weldments_list_items, weldments_create_frame, weldments_create_gusset, and weldments_create_end_caps. Everything else stays manual: Tab / Slot, Miter, Notch, Trim / Extend, per-corner overrides, Cutting List export, and editing an item that already exists are not available to the AI.

1. Open Fusion, open a Design document, and start Weldments.
2. Configure the AI client to launch Contents/mcp_server/run_weldments_mcp.cmd on Windows or Contents/mcp_server/run_weldments_mcp.sh on macOS.
3. Use weldments_get_status first. For face-dependent geometry, select the intended faces in Fusion before asking the AI to create a Gusset or End Cap.
4. Close any open Fusion dialog before asking the AI to build. Frame, Gusset, and End Cap requests are rejected while another Fusion command is running.

The bridge accepts loopback connections only, uses a random per-session token, exposes no arbitrary script execution, and requires an active Weldments license or trial for model changes. It starts whenever Weldments starts and cannot be switched off on its own; it listens on 127.0.0.1 only and stops when you stop the add-in in Utilities > Add-Ins. See Contents/mcp_server/README.md for client configuration examples.

• A free 3-day trial starts automatically the first time you use a Weldments tool (an internet connection is required to activate it). All tools are available during the trial.
• Buying on the Autodesk App Store unlocks the add-in through Autodesk Entitlement when you sign in to Fusion.
• If you received an activation code, open Info, paste the code, and click OK.
• Info is always available and shows current status, Autodesk account, App ID, and privacy links.
• Updates: Info also shows the newest build published by VanThanBK — an early-access build can be offered there before the App Store finishes reviewing it. Download latest version opens the download in your browser for licensed users (bought on the App Store, or granted access by the publisher); before updating, Stop the old add-in and clear Run on Startup in Utilities > Add-Ins. Close Fusion, replace the add-in folder, then restart Fusion before running the new version. Follow the update guide. Without a license the button takes you to the App Store page.
• Without a license or an active trial, every button stays on the ribbon but shows This Weldments feature requires a license and closes instead of opening. Info keeps working so you can check status or enter a code.

Website: Steel Frame & Weldments Pro

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