Heat the cure with controlled air
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Course: Fabricate composite race-car parts with workshop discipline
Module: Build sandwiches and bonded assemblies deliberately
Estimated duration: 55 minutes
The skill in this lesson is not simply getting a composite part warm. The skill is making the actual laminate, adhesive line, mould, and vacuum-bagged assembly experience the cure cycle the material supplier intended. That means you control circulated air, measure the component temperature, respect the specified ramp and dwell, and refuse to start the cure clock just because the oven controller says the air is hot.
This lesson sits between material qualification and bonded-assembly design. The sibling lessons cover choosing core, treating every interface as a load path, and avoiding brittle stiffness traps. Here you are doing the shop-control part: once the lay-up or bonded sandwich is bagged, how do you put heat into it without guessing, overheating, under-curing, distorting the mould, damaging a surface, or wasting a roll of pre-preg that was already beyond its useful out-life?
Principle: cure the part, not the air.
The oven air is only the transport system. The resin, film adhesive, and laminate do not care what the thermostat reads if the thickest part of the mould and the slowest-heating region of the component have not reached the required temperature. McBeath is explicit that the temperature of the laminate is what matters, and that cure timing starts only when the component has reached the required cure temperature. In practical shop terms, your cure log has two separate facts: when the oven air reached setpoint, and when the part reached cure temperature. The second one controls the dwell.
That distinction is the whole lesson. A thin area of a mould heats quickly. A thick leading edge, trailing edge, flange, tooling block section, or mass of solid aluminium heats more slowly. If you begin the dwell from the air-temperature controller, the thin region may receive the intended cure while the thick region receives less than the minimum time at temperature. The result can look cured from the outside and still be a weaker job internally because the material did not experience the schedule where it mattered.
Controlled air is useful because it can move heat evenly around an awkward assembly. A good workshop oven for this level of work needs a heat source, circulation, measurement, and enough insulation and control to avoid chasing the temperature. McBeath describes the general approach as heating and circulating air, with a heating element in external ducting and a fan recirculating the air into the oven. He also notes that small fan-assisted laboratory ovens may be viable for small components, and that some reach very high temperatures. The lesson is not that you need a glamorous oven. The lesson is that the oven must move heated air consistently and let you verify the temperature the component actually sees.
The mechanism: heat changes cure rate, flow, pressure, and defects.
Heat accelerates curing. In the pre-preg example McBeath discusses, each 10 degree C increase shortens the cure time substantially, and the supplier data gives the minimum cure temperature and minimum cure time. That does not mean you choose heat casually. Higher temperature is only useful when your oven, mould, bagging materials, release system, and material schedule can support it. If you cannot control 120 degrees C effectively, an 80 degrees C cure with the right material can be the better process. A slower controlled cure beats a faster uncontrolled one.
Heat also changes the resin state. Pre-pregs slowly cure at ambient temperature. Over time they stiffen, lose tack, and may not re-flow fully when later raised to cure temperature. If the resin does not flow properly among the fibres, the laminate is not internally bonded as well as it should be. This is why cure heat cannot rescue poor material handling. If the fabric has absorbed moisture, been contaminated with skin oils, or used up its out-life, the oven is not a magic reset button. The heating process can only complete the cure of a material system still fit to cure.
Heat changes trapped air too. Any air bubbles trapped within a laminate expand when heated and stress the surrounding material. Near a surface, and especially near a gel coat, those bubbles can exert enough pressure to damage the finish. This is why careful stippling, rolling, vacuum consolidation, and bag integrity matter before the oven ever turns on. The heat cycle exposes the quality of your lay-up. It does not politely ignore voids.
Heat also tests the mould. A mould used for pre-pregs must cope with the intended cure temperature. Wet lay-up moulds need post-curing before they are used at elevated temperature, and a polyester-based mould has practical temperature limits. McBeath gives perhaps 90 degrees C as a sensible maximum for a polyester-based mould, while also emphasizing that the mould must be post-cured at the temperature it will later see. A mould must remain thermally stable and physically stable. If it changes shape during cure, the part inherits that error.
Technique: build a cure plan before the oven is on.
Start with the supplier data for the actual pre-preg or adhesive. You need the cure temperature, the cure time, and the temperature ramp rate. The ramp rate matters because the supplier can specify a rate of rise in degrees per minute, and McBeath warns not to exceed it because of exotherm risk. Your first job is therefore not to ask how hot the oven can get. Your first job is to choose a cure option your oven can reach with effective control while staying inside the material schedule.
Next, decide what temperature you will measure. The oven controller is not enough. Put a thermocouple where it answers the real question: has the slowest-heating part of the component reached cure temperature? In McBeath's lower aerofoil-half example, the female mould may be thinner in the centre of the wing and thicker at the front or back edges. The thin areas heat faster than the thick ones. The cure should be timed from the thermocouple on the laminate above the thickest part of the mould, because that is the area most likely to lag. If that region gets the minimum time at temperature, the rest of the component should also receive at least the minimum.
If you are using both a temperature readout and a controller, separate their jobs in your head. The controller can manage heat input. The readout on the component tells you when the job has actually reached the required temperature. In a poorly insulated oven you may need to set oven air slightly above the required material temperature so the component stabilizes at the desired value. That adjustment is not guessing if you confirm it with the component thermocouple. It is guessing if you change the setpoint because you feel the part should be hot enough by now.
Then check the mould and release system. Any mould that will see elevated temperature should already have been post-cured to at least that temperature. A release agent that worked at ambient temperature may not work at higher temperature, and McBeath specifically cautions that wax release agents that work at ambient or slightly elevated temperatures may not cope with higher temperatures. Run trials with similar materials, the same mould or pattern style where possible, and the release agent you plan to use. The cure cycle is a bad time to discover that the part is permanently attached to the tool.
Now inspect the bagged assembly. The vacuum bag must pull down evenly everywhere, without excessive creasing and without bridging. Bridging matters because it lets the bag span a corner instead of pressing the laminate or adhesive stack into it. That can leave a poorly consolidated internal corner. Apply vacuum, get full vacuum, turn off the pump, and leak-check. Larger leaks may be audible. Smaller leaks show as a vacuum drop over a few minutes. The oven does not fix a leak; heat can make a marginal bag worse, and a leaking bag can cost consolidation while the resin is moving.
Once the bag passes, place the assembly in the oven with the vacuum pump running as required by the process. Use high-temperature tape for thermocouples, and route wires and vacuum connections so they do not pull, kink, or create bag stress as the assembly warms. Follow the supplier ramp. Do not start the dwell until the component thermocouple reaches cure temperature. Hold at least the dictated cure time. If the supplier provides multiple cure options at different temperatures, choose the option your oven can actually control, not the option that looks fastest on paper.
Sub-skill: air circulation.
An oven with still air can have hot and cold zones. A fan-assisted oven reduces that problem by moving heat around the part. McBeath's efficient design is a heating element in external ducting recirculating air with a fan. That arrangement helps keep the heat source from simply roasting one side of the component while leaving the other side to lag. The practical cue is that your thermocouples should converge toward a stable value rather than showing one area racing ahead while another remains far behind.
Good air circulation also helps post-cure work. McBeath's simple warm box used slatted shelves to allow convection, four light bulbs as heat, and a room thermostat. That example was modest, but it makes an important point: even a basic warm box should let air move. The shelf design mattered because components need circulated warmth, not a trapped hot pocket below them and a cool pocket above them.
Sub-skill: thermocouple placement.
A thermocouple should answer a process question. The most useful first question is usually: what is the slowest-heating part of this job? On a variable-thickness mould, the answer may be the laminate over the thickest section. On a sandwich assembly, it may be the region where the core, skins, adhesive film, caul, and mould mass create the largest thermal lag. On a small thin component in a laboratory oven, the lag may be small, but you still confirm it until you have evidence.
Do not hide the thermocouple in a convenient place if it does not represent the risk. A reading near the door, near the fan outlet, or on a thin flange may make you feel better while saying little about the adhesive line or laminate over the mould's thickest mass. The point is not to collect a number. The point is to time the cure from the point that proves the whole component has reached the required temperature.
Sub-skill: ramp discipline.
The ramp is not warm-up dead time. It is part of the cure schedule. If the supplier says the temperature should rise at a limited rate, respect that limit. The resin system is chemically active, and an excessive ramp can create exotherm risk. In a home workshop, this is where the urge to save an hour can ruin a job. A controlled ramp also gives the mould, bag, laminate, adhesive, and air mass time to move toward the same condition rather than forcing the surface to race ahead of the interior.
A good ramp feels boring. The temperature climbs predictably. The controller does not overshoot wildly. The component thermocouple follows the air temperature with a visible lag that you can explain. The vacuum remains stable. Nothing smells scorched. Nothing hisses. Nothing relaxes into a bridge. Boring is the sign that process control is doing its job.
Sub-skill: dwell timing.
The dwell starts when the component reaches the specified cure temperature, not when the oven first reaches setpoint. This is the mistake that makes uncontrolled curing look deceptively successful. The oven display may say the air is ready. The thickest part of the mould may still be climbing. If you demould later and the part looks hard, you may never connect a later bond-strength problem, surface defect, or weak laminate to the shortfall in true dwell time.
Record dwell start and dwell end against the component thermocouple. If you have multiple thermocouples, time from the last critical region to reach temperature. When in doubt, use at least the supplier's cure time for the selected temperature. Do not shorten the dwell because the part spent time approaching temperature unless the supplier's schedule explicitly allows that interpretation. The bonded chunks support minimum cure temperature and minimum cure time, not improvising credit for partial warm-up.
Sub-skill: pre-preg handling before heat.
The cure can only be as good as the material you put into it. Epoxy resins absorb moisture, and moisture reduces bond strength. Skin oils also impair bond strength, which is why gloves protect the part as much as the person. Track pre-preg out-life as a running total of time at ambient temperature. Do not order more than you can use in a reasonable time, and be especially careful with short out-life materials that can spend time in transport before they reach you.
Aged pre-preg is not merely inconvenient to handle. It can stiffen, lose tackiness, and fail to re-flow fully during cure. That matters directly to this lesson because controlled air cannot make expired material flow and bond as if it were fresh. If the fabric has used up its available out-life, the controlled cure may produce a controlled disappointment. The right action is to replace the material, not to raise the oven temperature in hope.
Sub-skill: mould qualification.
Before curing a part, ask whether the mould is qualified for that temperature. If it is a wet lay-up mould, it needs careful lay-up with entrapped air removed, because later heating can expand trapped bubbles and damage the mould. If it is polyester-based, keep its realistic temperature limit in mind. If it is solid aluminium or epoxy tooling block, confirm the surface finish and release treatment, and understand that different thermal mass can change how quickly the component reaches cure temperature.
Mould stability is both thermal and physical. It must withstand the temperature, and it must not change shape. A mould for pre-preg work is not ready just because it survived room-temperature laminating. It must survive the cure environment as a tool, not as an experiment attached to your first good component.
Sub-skill: vacuum integrity during heat.
Vacuum consolidation removes air and presses the stack together before and during cure. Breather and bleeder materials help air removal and may absorb excess resin. The bag must pull evenly, with tucks where needed to take up slack and avoid bridging. When the part is in the oven, the bag, sealant tape, through-bag fittings, and vacuum lines are all part of the cure system. Treat them as process hardware, not packaging.
The calibration cue is simple: before heat, the bag pulls down evenly and holds vacuum. During heat, the vacuum remains stable enough for the process, the bag shape remains acceptable, and no new bridge appears as materials soften and settle. If the bag loses vacuum or forms a bridge before the resin has cured, the assembly may no longer match the intended consolidation state.
Calibration cues: what improving looks like.
Your cure process is improving when you can predict the lag between oven air and component temperature. On the first cycle with a mould, you may be surprised by how long the thick section takes to catch up. On later cycles, your recorded data should let you estimate it closely. That is a strong sign that you are controlling a process rather than performing a ritual.
Your oven control is improving when the ramp rate is repeatable and does not overshoot the material schedule. A crude oven can still be useful if it reaches the selected temperature under control and holds it. A powerful oven that overshoots, recovers slowly, or creates large gradients is less trustworthy than a modest oven that behaves consistently.
Your bagging is improving when leak checks are uneventful. No hissing. No unexplained vacuum drop over a few minutes. No bag corners bridging across tight areas. No need to keep pressing tape while the oven is already warming. The oven cycle should begin after the bag is boringly sound.
Your material control is improving when every roll of pre-preg has an ambient-time record, every handler wears gloves, and no one argues that the oven will sort out questionable tack or contamination. The cure station is the last step in a chain. Good process control begins well before heat.
Your finished parts are improving when elevated-temperature post-cure stops producing surprises: no surface bursts from near-surface bubbles, no mould distortion, no release failure, no suspicious soft areas, and no unexplained weak bond lines. Absence of drama is not proof by itself, but repeated uneventful cycles with recorded temperature evidence are far stronger than memory.
Failure modes and recovery.
The first failure mode is starting the timer from the oven display. It feels efficient because the controller has reached setpoint. It costs you because the component may not have reached cure temperature, especially over thick mould sections. Recovery is procedural: move the cure-clock trigger to the component thermocouple, preferably at the slowest-heating critical region.
The second failure mode is treating maximum oven temperature as capability. A home-built oven that can hit 120 degrees C once is not necessarily a 120 degrees C process oven. Capability means controlled ramp, stable dwell, safe wiring, suitable materials, and component evidence. Recovery is to choose the cure option you can control, or get proper heating and electrical advice before building for higher temperature.
The third failure mode is heating a mould that was never post-cured for the job. The mould may distort, release poorly, or suffer damage from expanding trapped air. Recovery is to post-cure the mould to at least the intended working temperature before using it, and to qualify the release system at that temperature with trials.
The fourth failure mode is poor pre-preg stewardship. Moisture, skin oil, and exceeded out-life all attack the bond you are trying to create. Recovery is not a hotter cure. Recovery is gloves, moisture avoidance, ambient-time records, sensible ordering, and replacing material that has reached the end of its usable out-life.
The fifth failure mode is pushing the ramp. The part is in the oven, time is short, and the temptation is to heat faster. The supplier's ramp limit exists because the resin system has cure chemistry, and too fast a rise can risk exotherm. Recovery is to slow the ramp, accept the longer cycle, and build productivity through better planning rather than schedule abuse.
The sixth failure mode is using heat to reveal a lay-up defect you could have removed earlier. Entrapped air bubbles expand during elevated-temperature treatment and can damage surfaces. Recovery happens before cure: careful stippling, rolling, vacuum consolidation, suitable tissue behind gel coat where appropriate, and rejecting a bagged job that has obvious bridges or trapped air at critical corners.
How this connects to bonded sandwiches.
A sandwich assembly is only as good as its interfaces. The adjacent lesson covers that load-path idea. In this lesson, your job is narrower: make sure the adhesive or pre-preg interface sees the cure temperature and time it requires. McBeath's glossary defines film adhesive as a thin dry film that cures at elevated temperature and bonds core materials to laminate skins. That gives you the process target. The adhesive line, not merely the oven air, must receive the cure.
Sandwich work makes thermocouple thinking more important, not less. Core, skins, film adhesive, bagging stack, cauls, and mould mass can create thermal lag. If you are bonding core to skins with film adhesive, do not assume the surface temperature tells the whole story. Place the thermocouple where it best represents the adhesive line's slowest critical region, then time the dwell from that evidence.
The cure heat is also part of quality control for core bonds because vacuum and air removal matter. Breather material allows air removal from the vacuum bag, and bleeder may absorb excess resin. A bridge across a corner or a leaking bag means the interface may not be pressed as intended during the period when heat lets the resin or adhesive move and cure. The controlled-air oven is therefore only one part of a controlled assembly.
What not to overlearn.
Do not take one material's cure acceleration as a universal law. McBeath uses one pre-preg resin system to show the general principle that higher temperature can shorten cure time, but he also says other pre-pregs have different properties. Your supplier's sheet controls your schedule.
Do not assume high temperature is always better. The main advantage of shortened cure time is quicker mould release and re-use. Improved mechanical properties from post-cure may or may not be necessary for the component, though modest overnight post-cures can be beneficial when you are suitably equipped. The process decision should come from the part requirement, the material system, and the equipment you can control.
Do not treat this lesson as permission to improvise mains-powered ovens beyond your competence. McBeath is plain that when contemplating higher-temperature work, especially around 120 degrees C, proper advice from an electrician or heating engineer is prudent. A cure cycle is a controlled manufacturing process. Your heat source and wiring must be part of that control.
The practical rule.
Before heat: confirm material out-life and cleanliness, confirm mould post-cure and release suitability, bag the assembly without bridges, leak-check the bag, place thermocouples to represent the slowest critical region, and choose a supplier-approved cure option your oven can control.
During heat: circulate air, respect the ramp rate, watch the component temperature, do not start the dwell until the component reaches cure temperature, hold at least the required time, and keep vacuum stable.
After heat: let the process record tell you what happened. The most useful cure record is not a proud note that the oven reached setpoint. It is a trace or written log showing ramp, component-temperature arrival, dwell start, dwell end, and any bag or control issue. That record is how you make the next cure less like hope and more like manufacturing.
Worked example: lower aerofoil-half mould with uneven thickness
Imagine the job McBeath describes: a female mould for a lower aerofoil half. The mould is not a uniform slab. It may be thinner around the centre of the wing and thicker at the front or back edges. If you place a thermocouple on the thin centre area, the job will appear ready early. The controller will show the oven air at temperature, the thin laminate region will follow quickly, and the cure clock will start while the thick mould areas are still climbing.
The controlled-air method changes the decision point. Put the thermocouple on the laminate above the thickest part of the mould. Ramp at the supplier's permitted rate. Watch the air temperature and the component temperature separately. When the thick-region thermocouple reaches cure temperature, start the dwell. That timing should ensure that every part of the component receives at least the minimum cure time. The thin area gets no special praise for being early; the slow area sets the clock because it is the risk.
A good result is not just a part that comes out hard. A good result is a cure record showing that the slow region reached the required temperature before the dwell began, that the dwell lasted at least the specified time, and that the bag remained intact. If the part later has a defect, you can separate cure evidence from other causes instead of wondering whether the oven display fooled you.
Worked example: bonded sandwich skin-to-core film adhesive cure
For a bonded sandwich, the critical question is whether the adhesive line has experienced the cure schedule. McBeath defines film adhesive as a thin dry film that cures at elevated temperature and bonds core materials to laminate skins. That means the shop process must put controlled heat through the skin, adhesive, core, mould, and bagging stack while maintaining consolidation.
Do not treat this as a decorative warm-up of the outside skin. Bag the assembly so the vacuum pulls evenly, using breather where it is needed for air removal and leak-checking before heat. Avoid bridging because a bridged bag can fail to press the stack into a corner or contour at the moment the adhesive needs intimate contact. Place the thermocouple where it best represents the slowest relevant part of the bond, not where it is easiest to tape.
The cure clock starts when that representative component location reaches the required temperature. If the oven is weakly insulated and must be set slightly higher to bring the component to the required value, that is acceptable only when the component reading confirms the result and the material schedule is still respected. The success criterion is a bonded assembly whose cure record proves the adhesive line had the required time at temperature under vacuum, not a part that merely spent a while in warm air.
Worked example: modest overnight post-cure in a warm box
McBeath's warm-box example is deliberately modest: wooden packing cases, slatted shelves for air circulation, four light bulbs, and a room thermostat. The important teaching point is not to copy that exact box. It is to see that even a simple elevated-temperature post-cure needs air movement, temperature control, and watchfulness.
At around 50 degrees C, a post-cure can help a moulding reach maturity and improve laminate properties in the examples McBeath discusses. It can also shorten cure time enough to release a component sooner and re-use a mould. But the same rules still apply. The part needs circulated warmth. The mould and release system need to tolerate the temperature. Any trapped bubbles can expand. A basic warm box should therefore be treated as a process device with limits, not as a cupboard of hope.
The right use case is modest, controlled, and repeatable. If you are suitably equipped, an overnight post-cure can be worth doing. If you cannot measure the temperature, cannot keep air moving, or are unsure the mould or release agent can tolerate the temperature, you have not earned the post-cure yet.
Common mistakes
Mistake one is using the oven thermostat as the cure witness. The thermostat tells you about the oven control point. It does not prove the thickest part of the mould or the adhesive line has reached cure temperature. Good looks like a thermocouple on the laminate or component region that represents the slowest critical heating location, with the cure dwell timed from that reading.
Mistake two is choosing the fastest cure option instead of the controllable cure option. Supplier data may give different time and temperature combinations, and higher temperature may shorten cure time. But if your oven cannot hold that temperature with effective control, or if the mould, bag, release system, or wiring is not suitable, the faster option is not available to you. Good looks like selecting the highest schedule your equipment can control honestly, even if that means a longer dwell.
Mistake three is ignoring ramp rate. Heating faster feels productive until the resin system is pushed outside its specified rise rate and exotherm risk enters the job. Good looks like logging a controlled rate of rise and accepting that ramp discipline is part of the cure, not a delay before the real work.
Mistake four is heating an unqualified mould. A mould that works at room temperature may distort or suffer damage at elevated temperature, especially if it contains entrapped air from careless lay-up. Good looks like post-curing the mould to at least the intended working temperature, qualifying the release agent at that temperature, and rejecting moulds that cannot remain stable.
Mistake five is trusting expired or contaminated pre-preg. Moisture, skin oils, and exceeded out-life all reduce the chance of a strong laminate or bond. Good looks like gloves, moisture avoidance, ambient-time records, realistic ordering quantities, and replacing material once the available out-life is used.
Mistake six is accepting a marginal bag because the oven is ready. If the bag bridges, leaks, or pulls unevenly, heat will not make the consolidation state better. Good looks like full vacuum, an even pull-down, no bridging, and a leak check that holds before the assembly goes into the oven.
Drill: thermocouple lag map and controlled-air rehearsal
Run this drill before the next important elevated-temperature cure on a mould or assembly style you have not characterized. The count is two dry or scrap cycles and one live-cycle log. The duration is one preparation session plus the time required for your selected cure schedule. The success criterion is that you can identify the slowest-heating critical region, ramp without exceeding the supplier rate, and start the dwell from component temperature rather than oven-air temperature.
Cycle one is an empty-oven and dummy-load mapping run. Put one thermocouple where the controller senses or near the oven air stream, one on the mould or dummy component in a thin area, and one on the thickest or slowest-looking area. Ramp toward the intended cure temperature at the rate you expect to use. Record the time each location reaches the target. Do not cure a real part yet. You are learning how the oven and mass behave.
Cycle two repeats the run with the actual bagging arrangement if possible, using scrap or a noncritical assembly. Pull vacuum, check for leaks, route thermocouple wires and vacuum lines, and watch whether heating changes the bag shape. Record whether any bridge appears, whether vacuum drops, and whether the slow thermocouple lag matches cycle one. If the lag or bag behavior surprises you, solve that before a live part.
The live-cycle log is the first real part after the rehearsal. Use the slow-region thermocouple to define dwell start. Write down ramp start, target arrival at oven air, target arrival at component, dwell start, dwell end, vacuum observations, and any controller overshoot. The next time you run the same mould and material, compare the lag. Improvement means the numbers become predictable and the decisions become boring.
When to stop the cure plan
Stop if the bonded corpus conditions are not met in your actual shop. If you cannot measure the component temperature, you cannot prove the cure time. If the oven cannot ramp without overshoot or cannot hold the selected temperature, choose a different schedule or improve the oven. If the mould was not post-cured to the intended temperature, qualify the mould before risking a part. If the release agent has not been trialled at the planned temperature, test it first.
Stop if the bag does not hold vacuum or if it bridges anywhere important. Vacuum consolidation depends on air removal and even pressure before cure begins. A leak that seems small on the bench can become a quality problem during heat. Fix the bag while the resin is still uncured and while you still have choices.
Stop if the pre-preg material has an uncertain out-life record, has been exposed to moisture, or has been handled with bare hands. The cure oven cannot restore lost tack, undo contamination, or make aged resin re-flow fully. In that case the disciplined action is to replace the material or re-plan the job, not to push heat harder.
Author Review
No quiz questions are attached to this lesson.
Sources
| # | Document | Chunk | Pages | Score | Collection |
|---|---|---|---|---|---|
| 1 | Competition Car Composites Simon McBeath | 825b6653-b755-0ee1-9918-0bd19e4a9e04 | 163 | 1 | uio_books_raw_v1 |
| 2 | Competition Car Composites Simon McBeath | 7e966669-9121-12e4-9dcc-e9541db5aaaf | 153 | 1 | uio_books_raw_v1 |
| 3 | Competition Car Composites Simon McBeath | 646b6c1d-94be-1ae4-077f-baa8a3c089ab | 154 | 1 | uio_books_raw_v1 |
| 4 | Competition Car Composites Simon McBeath | 1fe17c3e-8271-2a70-7a9ffe2cba35 | 152 | 1 | uio_books_raw_v1 |
| 5 | Competition Car Composites Simon McBeath | 02409dce-7e26-4dc6-57e9-f9c9d3844926 | 139 | 1 | uio_books_raw_v1 |
| 6 | Competition Car Composites Simon McBeath | 055178b5-df8f-a5b4-d6fb-e1edf72c4cf3 | 156 | 1 | uio_books_raw_v1 |
| 7 | Competition Car Composites Simon McBeath | e7681fb9-23a0-7bc7-e029-4ec6bb0c593d | 135 | 1 | uio_books_raw_v1 |
| 8 | Competition Car Composites Simon McBeath | a92a57d7-66ad-7c18-c969-cf0c0d4005e9 | 204 | 1 | uio_books_raw_v1 |