What A, B, C and D actually mean
On a XANJO drawing, A is the overall length from the shoulder to the point, B is the shank diameter that seats inside the heater, C is the width of the working face, and D is the reach or bend offset on a bent geometry. Every drawing carries the legend next to the outline, because other suppliers use the same letters differently.
That last sentence matters more than the definitions. A buyer comparing two catalogues by letter alone will compare two different things. Always read the legend, then compare the numbers.
We publish these four fields for every geometry we grind — 400+ of them across 12 machine platforms. The values come from the grinding programme, not from a calliper held against a finished sample. If we change a profile, the drawing revision changes with it.
The shank is where fit is decided
The working face gets the attention, but the shank is what makes a tip usable. It has to seat fully in the heater bore: too loose and the thermal contact is poor, so the tip recovers slowly and the iron reports a temperature the joint never sees; too tight and it will not seat at all, or it scores the bore on removal.
We hold shanks to ±0.05 mm. On a 4 mm-class shank, an error of 0.08 mm is enough to turn a drop-in replacement into a part that has to be forced. This is the first thing to check when a “compatible” tip from another source wobbles in the socket.
| Field | What it controls | What we publish |
|---|---|---|
| A · overall length | Reach into the joint, clearance to the housing | Nominal value and tolerance |
| B · shank diameter | Seating, heat transfer, repeatability | Nominal value, ±0.05 mm |
| C · face width | Wetting area, thermal mass | Nominal value and tolerance |
| D · reach / offset | Access on fine-pitch and bent geometries | Nominal value, angle where applicable |
What a catalogue without measurements asks you to accept
Without dimensions, the selection process becomes an experiment paid for by the buyer. You order the minimum quantity, wait for the shipment, then discover the face is too wide for a 0.8 mm pad or the shank sits 2 mm too short to reach it. With a 20-piece minimum and a five-day sample lead time, that is a week lost to a question a drawing would have answered in a minute.
For a distributor the cost is larger: a part number that fits one iron but not the nominally identical iron from a different production year creates returns that nobody can explain. A published dimension set lets incoming goods be checked against a known value instead of against a photograph.
Where publishing stops
We publish geometry and plating data because we measure them. We do not publish heater power curves for third-party stations, we do not claim that our parts are identical to an original manufacturer's part, and we do not state a lifetime in hours — it depends on setpoint, alloy, flux and duty cycle, which are the customer's variables, not ours.
Brand and model names on our drawings describe which machine a tip fits. Write them as “for Weller WSP80” or “WSP80-compatible”. XANJO makes independent replacement parts and is not affiliated with, endorsed by or sponsored by any original equipment manufacturer.
If a geometry you need is not among the 400+ published, send the drawing or a sample part. Custom profiles are ground on the same line, with samples in five working days and a 20-piece minimum.
