Seat Shells PMMA acrylic in 4 mm for Defence And Security Equipment – Formed to Drawing

These PMMA acrylic seat shells are thick gauge vacuum formed parts supplied to drawing for defence and security equipment. They are formed from PMMA acrylic sheet at 4 mm, trimmed on 5-axis routers and inspected against the drawing before packing. Buyers choose this route where a metal fabrication is too heavy, or where injection moulding tooling cannot be justified for the volume.

Product specification

Key features

• One piece shell replaces a fabrication, so assembly hours drop
• PMMA acrylic keeps the weight down while stiffness is held through the formed shape
• Two coat polyurethane paint finish as standard, further finishes on request
• Trimmed on 5-axis routers, so mounting holes and cut outs match the drawing
• Tooling stored against the part number for repeat and spare orders
• RoHS compliant grades available

Typical applications

• antenna covers
• console covers
• case shells
• transport trays
• seat shells used across general defence and security equipment builds

How it is made

1. The part cools on a jig so the shape is held while the material stabilises.
2. Drawings are reviewed and a manufacturability report is issued with wall thickness, draft and radii marked up.
3. Tooling is cut: aluminium for production volumes, composite or printed moulds for samples and first articles.
4. Trimming is done on 5-axis routers or with a dedicated trim fixture to meet the drawing.
5. The sheet is formed over the mould with vacuum and, where the draw is deep, with plug assist.

Material: PMMA acrylic

PMMA gives the glossiest surface and the best UV stability, which is why it is used for light housings and outdoor sign faces.

Design notes

• use corner radii of at least three times the sheet thickness to avoid thinning
• add ribs or returns instead of increasing sheet thickness to save weight and cycle time
• hold the draw ratio near 1:1 for deep parts, or specify plug assist
• plan the trim line on a flat face so the router can hold tolerance

Finishing and assembly options

• two coat polyurethane paint
• as formed gloss
• silk screened markings
• Threaded inserts, PEM fasteners and brackets fitted before dispatch
• Mating parts can be trial assembled before the first article ships

Quality

Sheet thickness is checked on the formed part at the points shown on the drawing, and the readings go into the report. Batch releases carry a dimensional report, material certificate and, where agreed, PPAP or ISIR documentation.

• dimension reports with every release
• ISO 9001 quality system
• REACH compliant sheet available

Packing and delivery

Parts are stacked with interleaved film and packed in export cartons on pallets. Standard lead time to first article is 10–15 working days, and repeat releases ship against stored tooling without a new proving run.

Frequently asked questions

How fast is the first article?

Seven to fifteen working days from drawing release for sample tooling, with production tooling in three to four weeks.

Can you make it in another material?

Any grade in this family can be swapped in. Send the requirement and the material will be quoted with the price difference shown.

Are spare parts available later?

Tooling is stored against the part number for the life of the programme, so replacements or spare panels can be released at any time.

Request a quotation

Send the drawing or a photo of the current seat shells with the quantity and the finish required. The reply covers material choice, wall thickness, tooling route and price, so the decision is made on a complete picture.