# American Optical (AO) Spencer Glass Knife Maker
**Brand:** American Optical / Spencer | **Type:** Glass knife maker for ultramicrotomy

---

## Item Description

Vintage American Optical (AO) Spencer glass knife maker for use with ultramicrotomes and rotary microtomes. Used to score and break glass strips into triangular glass knives for cutting ultrathin sections (60–100 nm) for transmission electron microscopy (TEM) and thick sections for light microscopy.

The unit features the AO Spencer logo on the housing and includes the scoring/breaking mechanism with adjustable clamps and glass supports. Solid cast construction typical of AO Spencer instruments from the mid-20th century.

### What's Included
- AO Spencer glass knife maker unit
- Scoring/breaking mechanism
- See photos for exact configuration

### Condition
- Used, vintage condition
- Shows surface dust and age-appropriate wear
- Mechanical components appear intact

---

## Market Research

AO Spencer-branded glass knife makers are rare on the secondary market — most searches return LKB and other competing brands. Comparable items:

| Source | Item | Price |
|--------|------|-------|
| eBay | TAAB-Pyper ultra microtome glass knife maker | ~$75–$150 |
| eBay | LKB 7800 Knifemaker (comparable, more common) | $150–$400 |
| General vintage lab | AO Spencer lab instruments | $75–$250 |

AO Spencer instruments have collector appeal in addition to functional value. Buyers are TEM labs, university EM cores, and vintage lab equipment collectors.

---

## Recommended Listing

**Title:** `American Optical AO Spencer Glass Knife Maker Ultramicrotome TEM Sample Prep Vintage`

**Price:** $125–$175
- Rarer than LKB but less standardized
- Functional value to active TEM labs
- Collector/vintage appeal supports the higher end

**Category:** Business & Industrial > Healthcare, Lab & Dental > Medical & Lab Equipment > Microtomes

**Shipping:** USPS Priority Mail or UPS, ~$25–$45 (compact unit, manageable weight)

**Condition:** Used

**Key selling points:**
- Vintage American Optical / Spencer instrument — rarely available
- Used for making glass knives for TEM ultramicrotomy
- Solid mechanical construction
- Ships well

---

## Notes
- Verify whether scoring wheel is intact and functional — this is the key working component
- Note any missing parts (scoring wheel, glass strip guides) in the listing