Sound familiar?
- Two machine shops quoted wildly different prices from the same drawing
- Parts arrived that matched the drawing but still did not fit
- Nobody can tell which version of the drawing is current
- Your overseas supplier made a mirror image of the part
- Every dimension is toleranced to ±0.05 mm, and every part costs a fortune
Key facts
- Drawings follow BS 8888, the UK framework standard for technical product documentation
- First angle projection by default, third angle for North American suppliers, always with the symbol shown
- General tolerances stated in the title block, commonly to ISO 2768-1
- Geometric tolerancing (GD&T) used on the features that control fit and function
- Every sheet carries drawing number, revision, scale, units, material and finish
- £45 an hour + VAT, or a fixed quote for a defined drawing set
BS 8888 and ISO 128 in plain English
BS 8888 is the British Standard for technical product documentation and specification. According to BSI, the current edition is BS 8888:2020, and it acts as a route map to the ISO standards that cover drawing practice. The ISO 128 series covers how drawings look: line types and thicknesses, views, sections and hatching. Following them is not bureaucracy; it means any competent engineer or machinist can read your drawing the same way, without a phone call.
In practice our drawings show the minimum number of views needed to define the part, sections where internal detail matters, dimensions taken from functional datums rather than chained end to end, and notes only where geometry cannot say it.
First angle or third angle projection
Orthographic drawings show a part from several directions. The difference between the two systems is where those views sit on the sheet:
- First angle (usual in the UK and Europe): the view from the left is placed on the right of the front view, and the plan view goes below it.
- Third angle (usual in the USA and Canada): the view from the left goes on the left, and the plan view goes above.
BS 8888 allows either, provided the projection symbol is shown in the title block. Reading one system as the other produces a mirrored part, which is an expensive way to find out. We default to first angle and switch to third angle when a supplier asks.
Tolerances and GD&T
No part is made exactly to size, so a drawing must say how much variation is acceptable. Most dimensions are covered by a general tolerance note in the title block, commonly ISO 2768-1 medium class, which allows a different deviation for each size band. Only dimensions that genuinely matter get their own tighter tolerance.
Where position, flatness, perpendicularity or concentricity controls whether a part works, we add geometric dimensioning and tolerancing (GD&T): feature control frames referencing datums (A, B, C). UK and ISO drawings use the ISO GPS system; some American suppliers work to ASME Y14.5, and the symbols look similar but do not always mean the same thing, so we state which applies. The aim is to tolerance for function, because every unnecessary tight tolerance means slower machining, more inspection and a higher price.
Title blocks and revision control
The title block is the drawing's ID card. Ours include: company name, part name, drawing number, revision, sheet size and number, scale, projection symbol, units, general tolerances, material, finish or treatment, drawn by, checked by and date. A revision table records what changed, when and why.
Revision control stops the most common manufacturing mistake: making parts from an old drawing. We use one clear scheme (for example, letters for pre-release drafts and numbers once issued for production), put the revision in the file name as well as on the sheet, and never reuse a revision. See 2D CAD drafting if you need a reusable company template.
Common drawing mistakes we fix
- Chain dimensioning: dimensions strung end to end, so small errors stack up along the part. We dimension from datums instead.
- Over-dimensioning: the same size defined twice in different ways, which leaves the machinist guessing which one wins.
- No projection symbol: the cause of most mirrored parts.
- Missing material or finish: the supplier has to ask, or guesses.
- Unstated units or tolerances: a drawing with no general tolerance note gives no basis for accepting or rejecting a part.
- Drawing and model out of step: someone changed the model but not the drawing, or the other way round. Producing drawings directly from the model avoids this.
Price
Technical drawings are £45 an hour + VAT. A simple part drawing from an existing 3D model is quick; a full assembly pack with GD&T takes longer. Send your models, sketches or old drawings and we will quote a fixed price for the set. See prices.
What you get
- Dimensioned manufacturing drawings as PDF for quoting and sign-off
- DWG and DXF versions for your own records and CAM use
- General arrangement and assembly drawings with a parts list
- Detail drawings for each manufactured part
- A company title block template, if you do not have one
- A revision history table on every sheet
How it works and what it costs
Logos from £150, brochures from £295, photography from £295 a half day and CAD at £45 an hour, all + VAT. You get a fixed price before we start.
Tell us the brief
What it is for, who will see it, where it will be used and any examples you like. Rough is fine.
Fixed price
We confirm the price and what you get, in writing, before any work starts.
First designs
We design, shoot or model it and share the first version for your comments.
Refine
We make the changes, check every detail, and prepare the files properly for print, web or manufacture.
Final files
You get the finished files in the formats you need, ready for your printer, website, social channels or manufacturer.
Frequently asked questions
What is BS 8888?
BS 8888 is the British Standard for technical product documentation and specification. It brings together the ISO standards that govern engineering drawings, from line types to tolerancing. dijitul media lays out technical drawings to BS 8888 so that UK and international suppliers read them consistently.
Should my drawing be first angle or third angle?
For UK and European suppliers, first angle is normal. North American shops usually expect third angle. Either is valid under BS 8888 if the projection symbol is in the title block. dijitul defaults to first angle and switches when your supplier asks.
Do I need GD&T on my drawings?
Not on every feature. Plus and minus tolerances cover most simple parts. GD&T is worth adding where the position, flatness or alignment of a feature decides whether the part fits or works, such as bolt patterns, bearing bores and mating faces. Used selectively, it can make parts cheaper rather than dearer.
What does ISO 2768 in the title block mean?
It is a general tolerance standard. A note such as 'ISO 2768-m' tells the manufacturer that any dimension without its own tolerance may vary by the medium-class amount for its size. It saves putting a tolerance on every dimension and keeps the drawing readable.
Can you check drawings someone else made?
Yes. dijitul can review an existing drawing set for missing dimensions, unclear projection, over-tight tolerances and revision problems, and return a marked-up PDF. Checking is charged at £45 an hour + VAT, and we can make the corrections too if you want.
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Get a fixed price
Send a rough brief. You'll know exactly what it costs before we start.