Hundreds Of Products Ready Today. Dispatch/Collection Customer Question: Which Resin Seat Insert Kit For A Kirkey Intermediate?
Customer question, poly-bead seat inserts
A customer rang this week with a good question. He has a Kirkey Intermediate and he wants a resin insert giving full tub coverage, and he wanted to know which size kit to order. They come in six, from 15 litres to 90, and the difference between them is not comfort or quality. It is simply how much space you are filling.
The short answer we gave him on the phone was the 70 litre kit, and that is still the answer. What follows is why, so that anybody landing here with a different seat can work out their own size instead of guessing.
There is also one thing to know before you order, because it is not in the box and without it you cannot finish the job.
- Six sizes, and the only variable is how much space the insert has to fill
- Full tub coverage in a Kirkey Intermediate is a large fill, so the 70 litre kit is the one
- A smaller driver needs MORE resin, not less, because there is more void to fill
- The kit is a liner, the bead and resin mix and instructions, and you form it in the car
- Curing needs a vacuum pump, and that is not in the box. We add it to the order
- You get one attempt, so read the instructions fully before you mix anything
What a poly-bead insert actually is
If you have not made one before, the process is simpler than it sounds and more final than people expect.
The kit is a sealed liner filled with micro poly-beads and a slow curing resin. You mix the resin in the bottle supplied, get it into the liner, put the liner in the seat, and then the driver sits in it wearing what they actually drive in. You shift about until the beads have moved where you want them and the shape is right.
Then a vacuum is drawn through a valve on the liner. That pulls everything tight, locks the shape, and the resin cures around it. What you end up with is a seat that fits one person in one shell, which is exactly the point.
What arrives in the box
- The liner. Sealed and already filled with micro poly-beads, with the vacuum valve fitted.
- The resin. Supplied in the bottle you mix it up in.
- The instructions. Printed, in the box.
Not in the box: the vacuum pump. It is the one part you have to arrange yourself, and nothing cures without it.
The six sizes and what each is for
This is the whole decision. The kits are identical in what they do, and the litre figure is just how much bead and resin you get. Too little and you cannot fill the space. Too much and you have paid for material you are not using.
These are the maker’s own application notes, not our interpretation.
| Size | What the maker says it is for | Price |
|---|---|---|
| 15 litre | No application note published. Ask us before ordering this one | GBP 198.84 |
| 30 litre | Partial infill only, such as historic single seaters | GBP 263.27 |
| 40 litre | Infill for a single seater extraction seat, A1GP, F2, WSR or Formula Ford | GBP 277.68 |
| 50 litre | Open cockpits such as Formula Renault, Ginetta or an SF chassis | GBP 312.38 |
| 70 litre | Open cockpit sports cars and single seaters needing a larger area filled | GBP 349.54 |
| 90 litre | No application note published. The step up when 70 will not fill it | GBP 369.07 |
Why 70 litres for a Kirkey Intermediate
Full tub coverage means you are filling the base, the sides and the back of the shell in one piece. On a Kirkey Intermediate that is a lot of volume, and the maker describes the 70 litre kit as the one for cockpits that need a larger area filled. That is the match.
The 50 litre is the size below and its application note is written around open cockpit single seaters, which are a narrower fill than a full containment tub. Going down a size to save GBP 37 and then running out of material halfway through is the worst outcome here, because you cannot top it up once the resin is going off. Garreth is blunt about this one: on a job you only get one attempt at, the GBP 37 is not the number that matters.
If your shell is at the larger end, an 18 inch rather than a 15, or the tub is particularly deep, the 90 litre is the sensible insurance for another GBP 20.
The part that is not in the box
Every one of these kits is cured by drawing a vacuum through the valve on the liner, and the vacuum pump and hose is a separate item. It is not in the kit and it is not something you can improvise on the day.
It is a hand or foot operated pump, about GBP 48, and it lets you control the flow rate as the vacuum comes on, which matters more than it sounds when you are trying to hold a shape. It is not currently on the website as a product you can add to a basket, so tell us when you order the kit and we will put one on with it.
We would rather say that here than have somebody take delivery of a GBP 350 kit on a Friday for a Saturday fitting and find they cannot cure it.
Finishing it, and the optional extras
The cured insert is a bare moulded shape. The spacer fabric covering is what goes over it, and it is worth having: it breathes, it stops the surface abrading your suit, and it makes the finished job look like something you meant to do.
The inflatable lumbar pads are the other useful extra. They go in while you are forming the insert, so you can dial in lower back support and then leave it set. If you have ever finished a long stint with a sore back, that is the part to think about before you mix the resin, not after.
For full tub coverage in a Kirkey Intermediate, the 70 litre kit at GBP 349.54 is the size, and it is what we told the customer on the phone. Add the spacer fabric at GBP 47.40 to finish it and let us put a vacuum pump on the order. If your shell is at the big end or you are a slim driver in a large seat, ring Cameron before you order and he will talk you up to the 90 litre if it is warranted.
Doing it properly
A few things worth knowing that are not on the box.
Do it in the car, in the seat, on the mounts you will actually use. An insert formed on a workshop floor will not sit the same once the seat is bolted in at its real angle. Wear your suit, your boots and your helmet, and have your harness roughly where it will be, because all of that changes your shape in the seat.
Give yourself a warm dry space and a couple of hours. Slow cure means slow cure, and rushing the vacuum is how you end up with a shape you did not want.
And get somebody to help. You cannot hold your own position, work a pump and check the shape at the same time.
Questions about resin insert kits
Which size do I need for full tub coverage?
For a Kirkey Intermediate, the 70 litre. Full tub coverage fills the base, the sides and the back in one piece, which is a large area, and that is exactly what the maker scopes the 70 litre kit for. Step up to the 90 litre if your shell is at the larger end or you are a slim driver with a lot of space to fill.
Surely a smaller driver needs a smaller kit?
It is the other way round. The insert fills the space between you and the shell, so a smaller driver in the same seat leaves more space to fill and needs more material. The maker specifically describe the 70 litre as suiting a Formula Renault or F3 cockpit to accommodate a smaller driver.
What is in the kit?
The liner with its vacuum valve, the micro poly-beads and slow cure resin, a mixing bottle and full printed instructions. What is not in it is the vacuum pump and hose, which you need to cure it. Tell us when you order and we will add one.
Can I redo it if I get the shape wrong?
No. The resin cures once and that is the shape you have. That is why it is worth setting the seat at its final angle, wearing what you drive in and having somebody helping before you mix anything. Read the instructions all the way through first.
Will it fit any seat?
The insert is formed to whatever shell you make it in, so it suits a containment seat, a bucket or a single seater tub. What it will not do is transfer between seats. If you change the shell later you make a new insert.
Do you still sell Kirkey seats?
Not as a listed product on the site at the moment. That does not stop us helping with one. If you are running a Kirkey and want an insert, mounts or belts to suit it, ring us and we will sort it out.
Tell us the seat and the driver
If you are between two sizes, tell us the shell, its width, whether you want full tub coverage or just a base infill, and roughly the build of the driver. That is enough to give you a straight answer instead of a range.
Ring 0115 9893488 and we will get the right kit and a vacuum pump on the same order, so nothing arrives half finished.