From the quotation to the cutting list, without rebuilding the job

There is a moment in every won job where the quotation stops being a sales document and has to become instructions. Somebody takes the accepted quotation, works out what steel to buy, and works out what pieces to cut.

In most shops that is a person with a calculator, doing again — from the same dimensions — arithmetic that was already done to produce the price. It is the single most avoidable duplication in the business, and it is where the customer’s job and the shop’s job quietly become two different jobs.

Why they drift apart

The estimator quoted a 72 by 30 top and allowed two inches all round for the fold, so the price carries a 76 by 34 blank.

The person planning the cut looks at the drawing, sees 72 by 30, and allows an inch and a half because that is what he has always done.

Nobody is wrong. But the job now consumes slightly less than was quoted, or slightly more, and across forty lines it adds up in a direction nobody is tracking. Then the sheet order is placed against the second set of numbers, and at the end of the job the material variance is a mystery.

The same happens with grade on a mixed job — a 304 top on a 202 frame is a sensible piece of engineering and a common one — and with gauge, where an 18 SWG undershelf quoted and a 16 SWG one cut is a real cost that shows up as “steel was expensive this month”.

The quotation already knows

This is the part worth sitting with. To produce the price, the quotation had to work out:

• Which material each part is made of, at what grade and gauge.
• How much of it, in the unit it is bought in.
• What the blank size is, including the bend allowance.
• How many of each, across every line and every quantity.

That is a bill of materials. It exists already, as a by-product of pricing. The only reason it gets rebuilt is that most quoting processes throw the working away and keep the total, which is why Sazinga Quote stores the working — the material, the blank and the allowance behind every line — rather than only the number the customer sees.

Two documents fall out of it without anybody doing arithmetic twice.

The bill of materials is the buy list: this job consumes so much 16 SWG 304 sheet, so much 50 mm square tube, twenty-four bullet feet, two bowls, six filters. Aggregated across every line, so it answers “what do I order” rather than “what does line four need”.

The cutting list is the flat pieces, at blank size, before anything is folded: a top panel at 76 by 34, an undershelf at 74 by 32, and so on. It is what the person at the shear works from.

Nesting answers the question that actually matters

A cutting list on its own tells you the pieces. It does not tell you how many sheets to buy, and that is the question the purchase decision needs.

Nesting lays the pieces onto standard sheet sizes — 1220 by 2440 and 1220 by 3048 are the usual ones — and counts them. A rough nest is enough here. You are not optimising a CNC path, you are answering “nineteen sheets” instead of “about twenty, I think”.

On a demonstration quotation for a five-line commercial kitchen, the answer comes to nineteen sheets. That number is available the moment the quotation is priced, not after somebody has spent an afternoon on it.

Two useful consequences:

You can see the waste before you buy. If a job nests badly, sometimes a small dimension change the customer does not care about saves a whole sheet. That conversation is only possible if you know before ordering.

The purchase order matches the quotation. Same source, same allowances, same grades.

What this does not do

Worth being straight about the limits.

It does not replace the drawing. Bends, welds, radii, hole positions — none of that is in a cutting list, and a fabrication drawing is still a fabrication drawing.

It does not make nesting optimal. A first-fit arrangement is good enough to count sheets. A shop running a laser with real nesting software will do better, and should use it.

It only knows what the formula told it. If the pricing formula does not model the splashback’s blank, the cutting list will not have it either. Garbage in, consistent garbage out — which is at least better than two different sets of garbage.

The point is not the paperwork

It is that the shop and the customer are working from the same job.

When the buy list is derived from the priced quotation, a material variance at the end of the job is information — the job genuinely consumed more than expected, and that is worth investigating.

When the buy list is rebuilt by hand from the drawing, a variance tells you nothing, because you cannot tell whether the job was mis-estimated, mis-cut, or just re-derived with a different bend allowance by somebody who was not in the room when it was quoted.

One of those is a business you can improve. The other is one where every job is a surprise.