Who This Checklist Is For

If you're sourcing semi rimless glasses for a shop, a small chain, or a private label, this is the checklist I run before I let a purchase order leave my desk. I'm the office administrator for a 40-person company — I handle all our eyewear sourcing, roughly $180,000 a year across six vendors, and I report to both operations and finance. Which means I catch it from both ends: ops wants frames on the shelf, finance wants the invoice to match the PO and the packing list, and I'm the one standing in the middle when those two don't line up.

Seven steps, in the order I actually do them. Figure on two to three hours of real work spread over about a week, most of it waiting on replies.

Step 1 — Decide Which Semi-Rimless Build You're Buying

Here's the thing nobody tells you upfront: half rim eyeglasses isn't one product. It's at least two, and they behave differently in production.

The first is the nylon-cord mount — the lens is grooved, a cord runs under tension around the bottom half, and the frame holds it at the bridge and endpieces. The second is a metal channel or a screw-and-locking-block mount, where the lens edge sits in a channel and gets pinned. Materials stack on top of that: stainless, monel, beta-titanium, titanium, or a metal front married to TR-90 temples.

Ask the vendor to state the construction, the alloy, and the mount type on the quote. If the quote just says semi-rimless glasses, you don't have a spec — you have a category. I've watched a 900-piece order get built the wrong way because two people read that phrase and pictured different frames.

Step 2 — Put the Measurements in Writing

Frames are measured on the boxed lens system defined in ISO 8624 (check the current version — it's the reference for how lens width, bridge, and temple length are expressed). Whatever the vendor's house terminology is, your spec sheet should carry, in millimeters:

  • Lens width and lens height (B measurement)
  • Bridge width
  • Temple length, measured the same way both of you mean it
  • Total frame width
  • A tolerance per dimension — not the word standard

ISO 12870 is the general requirements and test standard for spectacle frames, and it's the one I point to when someone tells me their tolerances are normal. Normal isn't a number. If semi rimless glasses for men are the line you're buying, the lens width typically runs larger — 54 to 58 mm is common — so write the number instead of assuming the men's version of a unisex pattern.

Step 3 — Specify Finish, Color, and Nickel Release Separately

Three different things get bundled into the word quality, and each one needs its own line on the spec.

Color

Give a Pantone reference and a tolerance. Industry practice for brand-critical color is Delta E under 2; Delta E between 2 and 4 is noticeable to a trained eye, and above 4 most people will see it. That's fine for a black frame, not fine for a branded gold.

Plating and adhesion

Name the plating thickness and the substrate. Ask how they test adhesion, and ask for the actual method rather than a yes.

Nickel release

If you sell into the EU, nickel release from parts in prolonged skin contact is limited to 0.5 µg/cm²/week under REACH Annex XVII, entry 27, tested per EN 1811 with wear simulation under EN 12472. As of January 2025 that limit hasn't moved, but confirm current requirements at the EU source before you rely on it.

Here's something vendors won't tell you: a nickel test report is usually issued per alloy and plating combination, but it gets forwarded as a general company credential. Check that the report's alloy, plating, and part match the quote in front of you. I've seen a valid 2021 report attached to a completely different temple alloy.

Step 4 — The Step Most Buyers Skip: Confirm the Lens Groove with Your Lab

I didn't fully understand how much this matters until a batch came back in March 2023 with chipped edges along the groove. The frame was fine. The frames still are fine. The problem was that nobody had asked the lens lab whether they could groove to the profile the factory designed around.

So now I do this before I approve anything:

  • Ask the factory for the cord or channel profile they designed the frame for — diameter, groove position, groove depth
  • Ask your lab for the minimum edge thickness they need to cut that groove safely, and what happens at high minus or high plus powers
  • Ask whether they notch in-house or send it out, and how that affects turnaround
  • Confirm the impact-resistance requirement. In the U.S., prescription lenses must pass the drop-ball test under 21 CFR 801.410 — a 16 g steel ball dropped from 127 cm — and a grooved edge concentrates stress in a way a full-rim edge doesn't

The assumption is that the frame factory owns this question. The reality is they own the frame, and your lab owns the lens, and the groove lives exactly on the line between them. Somebody has to stand on that line. Make it you.

Step 5 — Approve a Master Sample, Then Ask Where It Was Made

Golden sample, master sample, whatever your vendor calls it — get one physically in your hands, signed and dated, with color chips and the measurement sheet, and keep a second one sealed.

Then ask the question that decides whether that sample means anything: was this made in the sample room or on the production line? In a lot of factories those are two different rooms with two different levels of attention. What most people don't realize is that sample-room output is the best case, not the average case.

Write it into the PO: three pieces from the first bulk run, air-freighted, approved by you before the balance ships. Costs a little. Cheaper than a container of frames nobody wants.

Step 6 — Compare Quotes on Landed Cost, Not Unit Price

Line up every quote on the same twelve lines before you compare anything: unit price, tooling and mold cost, logo method, plating upgrade, case and cloth, retail packaging, freight, duty, payment terms, defect allowance, replacement policy, and quoted lead time.

Here's a real example from quotes I collected in November 2024. Vendor A came in at $4.10 a unit. Vendor B came in at $4.85. On a 1,200-piece run that's a $900 gap, and procurement at that moment in my career would've taken the $900.

Then I read the scopes. B included the case, the branded cloth, the upgraded plating, and a 30-day production window. A's price excluded the case, used a lower-grade plating, and quoted 55 days with a disclaimer about the plating line. Add the case at $0.55 and the plating at $0.30 and the gap shrinks to almost nothing — and you still have three extra weeks of inventory exposure.

My rule of thumb, from five years of doing this: the lowest quote is the one I have to re-scope, not the one I sign. In my experience the lowest number has cost us more in about 60% of cases.

And don't skip the defect math. A 2% reject rate on 1,200 pieces is 24 frames. If replacements ship by air and the shelf is empty for six weeks, that $900 you saved is gone and then some.

Step 7 — Write the Inspection and Payment Terms into the PO

Vague POs are where the arguments live. Mine now carry:

  • A sampling plan with a number — AQL 2.5 for major defects, 4.0 for minor, per ISO 2859-1
  • A definition of major for this product specifically: cord tension or slack, groove burrs, hinge play, temple-to-front alignment, uneven plating, solder points, logo position, temple tip fit
  • Who owns the tooling and the logo artwork, stated plainly
  • A replacement window and who pays freight on rejects
  • A three-way match requirement — PO, packing list, commercial invoice — before finance releases payment

That last one isn't bureaucracy. When a vendor can't produce an invoice that matches the PO, I'm the one explaining it to finance, and the money comes out of somewhere. So I verify paperwork capability before I place an order, not after.

Common Mistakes I Still See

Approving a sample from photos. Color on a screen is not color. Delta E doesn't survive a phone camera.

Accepting the word standard as a tolerance. If there's no number, there's no spec.

Comparing quotes with different scopes. Cheapest at first glance is usually cheapest because it's smaller. Same rule I apply to office supplies, and it hasn't failed me yet on frames.

Forgetting the packaging in the spec. Semi-rimless frames are the most sensitive of the three main constructions to cord damage in transit. Ask for the case configuration and the drop-test result on the export carton.

Assuming the regulation is frozen. Standards get revised and rates move. Verify current versions of ISO 8624, ISO 12870, EN 1811, and 21 CFR 801.410 at the source, and re-verify pricing every quarter — the numbers above are from a specific window and will age.

Bottom line: a half-rim frame has fewer parts than a full-rim one, which makes it feel simple. It isn't. It's simple in exactly the place where the lens, the frame, and the lab all meet, and that's the seam you have to own.