The short answer
On SLM (laser powder-bed) thin-wall RFQs, **support strategy** is a design-and-orientation note—not the same thing as “remove supports and skim.” Thin walls warp, overheat and pick up witness marks where supports attach. A self-supporting angle, a named keep-out on cosmetic skins, and an allowed support landing on a later-machined pad all change powder, recoater risk and finishing time. Silence on **where supports may touch**, **which walls must stay unsupported** and **build orientation** is what widens many [quote-new.php](https://3dwk.com/quote-new.php) **rates.v1.1** / powder estimate bands—not the wall thickness callout alone.
This guide is for buyers packaging titanium or aluminum SLM brackets with walls that sit near process minimums. Illustrations use an **Example part** only—not a customer flight fitting. Related notes live in [SLM support removal and skim notes](https://3dwk.com/resources/slm-support-removal-and-skim-notes), [SLM build orientation notes for buyers](https://3dwk.com/resources/slm-build-orientation-notes-for-buyers), and [minimum wall CNC vs SLM for buyers](https://3dwk.com/resources/minimum-wall-cnc-vs-slm-for-buyers); here we focus on **support strategy on thin walls** so estimators do not guess attachment faces.
What a support strategy means for quoting
Supports hold down-facing geometry, conduct heat and stop recoater collisions. On a thick pad they are a removal-and-skim problem (the sibling article). On a **thin wall** they are also a distortion and witness-mark problem: removing a support can pull or scar a 1 mm skin, and leaving a wall fully unsupported at a shallow angle can make the wall fail in-process. Process pages for aerospace titanium ([SLM Ti-6Al-4V aerospace](https://3dwk.com/en/slm/ti-6al-4v/aerospace.html), [SLM Ti-6Al-4V](https://3dwk.com/en/slm/ti-6al-4v.html), [CNC 3-axis Ti-6Al-4V aerospace](https://3dwk.com/en/cnc-3axis/ti-6al-4v/aerospace.html) for later skim) assume orientation and support-landing notes when walls are light.
Do not bury “minimize supports” inside a notes cloud. Put **THIN WALLS 1.2 mm; SELF-SUPPORTING ORIENTATION PREFERRED; SUPPORTS ALLOWED ONLY ON PAD B (SKIM AFTER); NO SUPPORTS ON COSMETIC SKIN A** on the PDF and mirror it in RFQ text. Background: [DFM checklist before an online CNC quote](https://3dwk.com/resources/dfm-checklist-before-online-cnc-quote), [SLM vs CNC hybrid part strategies](https://3dwk.com/resources/slm-vs-cnc-hybrid-part-strategies).
Orientation, downskin and keep-outs
Typical buyer guidance (not a guarantee) is to treat walls that sit shallower than a self-supporting angle as needing either a redesign, a rotation, or an allowed support landing. Name the faces that must stay cosmetic (no support touch) and the pads that will be CNC skimmed later—those pads are the right place to land supports. Downskin roughness on unsupported shallow faces is a finish note, not a surprise after delivery; sibling: [surface roughness Ra callouts that raise quotes](https://3dwk.com/resources/surface-roughness-ra-callouts-that-raise-quotes) and [lattice infill notes on SLM structural parts](https://3dwk.com/resources/lattice-infill-notes-slm-structural-parts) when a lattice replaces a thin solid skin.
Powder and build $/cm³ planning bands for Ti-6Al-4V sit well above aluminum under **rates.v1.1** / powder tables; support volume and failed-wall risk move the band more than a tenth of a millimeter of extra skin.
When supports on a thin wall are acceptable
Allow supports on a thin wall when that wall will be hidden, will be machined, or can tolerate a witness that you have named (for example “support witness OK below datum floor”). Do not allow them on a sealed or cosmetic skin unless you also accept blend time. Internal channels need an escape/access note so supports are not trapped—another **needs_manual** classic. Hybrid plans (SLM near-net + CNC skim on pads) should list which faces are stock-for-machine so support scars get cut away.
Tolerance and inspection traps
Calling “thin wall, no supports anywhere” on geometry that cannot stand at a self-supporting angle, or “supports OK” on every downskin including sealing faces, both force wide bands. Default non-critical envelope to a general tolerance you actually use and put functional GD&T on skim pads, not on as-built thin skins unless you mean it. Related: [GD&T callouts that raise CNC quote bands](https://3dwk.com/resources/gdandt-callouts-that-raise-cnc-quote-bands), [powder reuse notes for SLM buyers](https://3dwk.com/resources/powder-reuse-notes-slm-buyers).
Illustration 1 shows an **Example part** thin-wall bracket with support keep-outs on a cosmetic skin and allowed landings on a skim pad.
Example part walkthrough
**Example part:** Ti-6Al-4V SLM bracket with a 1.2 mm web, two solid datum pads with 0.6 mm skim stock, ISO-style general on non-critical edges. With STEP + **ORIENT WEB NEAR VERTICAL; SUPPORTS ALLOWED ON PADS ONLY (SKIM AFTER); NO SUPPORT TOUCH ON WEB A; DOWNSKIN ON WEB ACCEPT AS-BUILT**, expect a usable automatic planning band on [quote-new.php](https://3dwk.com/quote-new.php). Same geometry with silent CAD and “minimize supports / cosmetic all over” often lands DFM notes or **needs_manual**—without inventing any customer flight PO.
Illustration 2 contrasts a vague RFQ (“thin wall, supports as needed”) versus a labeled keep-out-and-pad pack and the clearer estimate path.
What widens bands fastest
Cosmetic-all-over plus shallow thin walls, trapped internal supports, skim pads that were also marked “no support,” and wall thickness called only as “as thin as possible.” Quantity breaks help unit nesting but do not erase orientation risk—see [how quantity breaks change CNC unit cost](https://3dwk.com/resources/how-quantity-breaks-change-cnc-unit-cost) and [what needs_manual means](https://3dwk.com/resources/what-needs-manual-means-preliminary-quote).
What to do next
Name **wall thickness**, **support keep-outs**, **allowed landings** and **orientation intent**, then upload on [quote-new.php](https://3dwk.com/quote-new.php). Service pages: [CNC machining](https://3dwk.com/cnc-machining-service.php) for skim ops, [materials](https://3dwk.com/materials.php). Treat **rates.v1.1** min/mid/max and powder estimates as estimates, not invoices. If the UI shows **needs_manual**, answer the support-strategy questions rather than forcing a fake firm price.
Common questions
Is this the same as support-removal notes?
No. Removal and skim happen after the build. This page is about where supports are allowed to exist so thin walls survive and stay cosmetic where you care.
What angle is “self-supporting”?
Treat published angles as typical process guidance, not a promise. Put the real requirement on the RFQ: which faces may receive supports.
Can I forbid all supports?
Only if the geometry and orientation can stand without them. A blanket ban on a shallow thin wall usually becomes **needs_manual**.
Where should supports land if I need them?
On pads you already plan to CNC skim, or on hidden faces you have marked “witness OK.” Do not land them on sealing skins unless you also buy blend time.