Square Base Brush Seal
A small square base carrying a handful of rigid strands mixed with soft filament, rather than the full-width filament bed used on our other lines. Two base forms: plain, or with a raised director each side of the tuft. Already running in production for a U.S. buyer.
Made to order Base size, filament height, strand mix and colour — all specified by you. Standard sizes run on existing tooling; non-standard is the larger half of what we run.
Also called stiff-filament brush seal, mixed filament brush seal, stiff bristle brush seal, combination brush seal, diamond base brush seal and square base pile weatherstrip.
Made to your channel, not ours
The two dimensions called out on that drawing are both yours to set. Strand mix, base size and whether you want pile directors are all variables here — tell us how many rigid strands versus soft filament, the base footprint, and how hard the opening is cycled.
No tooling charge
- Pile height
- Anything from 2.5 mm upward
- Fin or no fin
- Added or removed on any construction
- Silicone treatment
- Siliconized filament on any size we make
- Put-up
- Spool length and core to suit your requirement
- Private label
- Your label on the spool flange, printed with your size, colour and quantity — we already run this for other buyers
New tooling, on us
- Colour
- Multiple standard; custom matched on request
- Non-standard backing width
- We cut the die and carry the cost — nothing to pay up front
- Non-standard backing profile
- Same terms. Post us 50 mm of the extrusion and we cut to it; the die stays reserved to your part number
Send a drawing, and post us 50 mm or more of the extrusion — we match the backing to the section itself. Any tooling we have to cut is ours to pay for, and it stays reserved to your part number. Large suppliers sell from a fixed catalogue and treat a non-standard size as an inconvenience. We were built the other way round.
Why this construction
Mixing a small number of rigid strands into an otherwise soft brush is a standard way to add stiffness and wear resistance without losing the soft filament's sealing contact — useful where the brush has to hold its shape against repeated mechanical contact. If your opening works the brush that hard, send the drawing and we will confirm the strand mix against it.
Where it is used
- Already in productionCurrently supplied to a U.S. buyer on this base.
- Square base, compact footprint3–3.2 mm × 3–3.5 mm — smaller than our standard flat backing.
- High-cycle openingsSpecify pile directors where the tuft is worked hard enough to lay over.
Sizes
Ranges below apply to this line. The full backing-width table, with the U.S. nominal each size sits against, is on the specifications page.
| Attribute | Range |
|---|---|
| Base size | 3.0 – 3.2 mm × 3.0 – 3.5 mm |
| Filament height | 9.5 – 25 mm (0.374″ – 0.984″) on current tooling |
| Construction | Rigid strands plus one soft filament |
| Pile-to-backing bond | Heat-fused, polypropylene to polypropylene — no adhesive in the bond |
| UV stabilisation | Available on request — dosed to the filament, base yarns and backing film |
| Colours | Multiple standard; custom on request |
| Dimensional tolerance | ±0.15 mm |
| Standard spool length | Made to your put-up — tell us the run length |
| Minimum order quantity | Scales with price — small runs welcome, quoted per volume |
| Sample lead time | 15 days on existing tooling; 30 days if a new backing profile has to be cut |
| Production lead time | 15 days ex-works on a first order, from receipt of deposit. U.S. contract volumes have run 30–45 days. Add 10 days if the filament colour has to be spun to order. |
How to specify it
Four things get you a quote and a matched sample. If you only have two of them, send two.
- The backing width you runGive it however you have it — .270″, 7 mm, or the die drawing. We convert.
- The pile height you needOr the gap you are sealing, if the height was never specified.
- Fin or no finAnd silicone treatment or not. These are the two that change the part number.
- Annual volume and colourRough is fine. It decides the run size, not the price of the sample.
Related lines
Spec sheet — Square base brush seal
This line’s own sheet: its section drawing, its published ranges, and the backing-width routing table. Fields still being confirmed with the plant are marked as such rather than filled in with a guess.