Choose the core for the loads it must survive
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Course: Fabricate composite race-car parts with workshop discipline
Module: Build sandwiches and bonded assemblies deliberately
Estimated duration: 55 minutes
Principle: choose the core by the job it must survive
The core is not just the material in the middle of a sandwich panel. It is the choice that decides what the part is allowed to become. In one place, the job may be to make a large flat panel stiff without piling on more laminate. In another, the job may be to let a structure crush progressively in an impact. Somewhere else, the job may be to survive heat, moisture, fatigue, edge exposure, or a bonded hard point. The mistake is to ask which core is best. The useful question is narrower: what must this exact area survive, and what will count as acceptable evidence before it goes on the car?
That is the rule for this lesson: choose the core from the survival requirement, not from the prestige of the material. Competition-car composites range from wet-lay-up GFRP through carbon, aramid, and sandwich structures. That range is useful because different areas of a car need different properties. A nosecone, an undertray, a dash panel, a bulkhead, a wing mounting panel, and a tub side do not have the same job. A single part can even need different material decisions by location. Race-car composite design commonly mixes carbon, aramid, glass, woven cloth, unidirectional cloth, and local reinforcement so that the material package matches the load and abuse in that zone.
The practical mechanism is simple enough to teach even when the professional calculations are not available. Large flat areas that do not gain stiffness from shape often need sandwich construction. Curved areas may need a core that bends cleanly into the mould. Honeycomb panels can make very strong and stiff flat structures, but they bring edge sealing, hard-point, and damage questions with them. Some honeycombs are chosen because they crush in a useful way during impact. Some are chosen because they resist hostile environments better than cheaper alternatives. Some foam and mat cores are chosen because a home builder can make them follow a shape without expensive equipment. None of those reasons is the same reason.
If you take only one habit from this lesson, make it this one: before you pick a core, name the failure mode you are designing around. If you cannot say whether the part is more likely to fail by flexing, crushing, delaminating at a hard point, absorbing water through an exposed edge, softening in heat, cracking too brittlely, or being illegal in your class, you are not ready to buy core.
Keep the scope clean. The sibling lesson on bonding every interface owns the full adhesive-load-path discussion. The sibling lesson on brittle high-stiffness traps owns the deeper warning about stiffness without toughness. The cure and pre-preg lessons own oven control, moisture control, out-life, and cure qualification. Here, you are doing the selection step: deciding whether the core should be foam, Coremat, honeycomb, no core at all, or a locally different build around a hard point or exposed edge.
The core-selection sequence
Use the same sequence every time. It is slower than guessing for the first ten minutes and much faster than repairing a wrong sandwich after it has been bonded.
First, divide the part into zones. Do not select one core for the whole part just because the part has one name. Mark the large flat areas, tight curves, free edges, bolt locations, brackets, hard points, expected impact zones, hot zones, wet zones, abrasion zones, and any place the scrutineer may care about material choice. This zoning habit is supported by the way serious composite design treats material choice as location-specific. One area may need carbon for compression resistance, another may need Kevlar or aramid for tensile and impact behavior, and another may need alternating or hybrid cloth to get a blend of properties. The same logic applies to the core. A panel can be honeycomb in the flat, foam in a curve, solid laminate around an insert, and locally reinforced where a fastener or bonded bracket enters the load path.
Second, identify whether the primary problem is stiffness, shape, impact, environment, or attachment. A large flat body panel with little integral rigidity is a different problem from a crush structure. A curved duct wall is a different problem from a bulkhead. An exposed honeycomb edge is a different problem from a sealed internal panel. A panel beside heat or moisture is a different problem from a cockpit trim piece. If you mix those problems together, you will overbuild the easy areas and underthink the dangerous ones.
Third, reject the prestige answer. Carbon, aluminium honeycomb, aramid honeycomb, and ultra-high-modulus carbon can all be correct in the right place, and wrong in the wrong place. Professional cars use carbon over aluminium honeycomb in chassis and carbon or aramid over honeycomb in panels, but they also use test machines, controlled production, skilled laminators, and rejection standards. The home or club builder can borrow the principles, but not the assumption that a professional-looking material stack automatically brings professional confidence.
Fourth, choose the core family before choosing the exact product. At this level, you are deciding foam versus mat versus honeycomb versus pre-made sandwich board versus no core. Product data matters later, but the family decision comes first. The family decision is driven by the part's geometry and abuse. Flexible foam or Coremat can make sense where a curved area needs sandwich construction. Rigid foam can make sense where a flat or gently shaped area needs added depth and stiffness without huge laminate thickness. Honeycomb can make sense for flat panels where stiffness and weight matter, or where a known crush behavior is desired. Pre-manufactured honeycomb sandwich board can make sense when you need a simple flat panel and can work within the fabrication methods. No core can be the right answer around fasteners, impact edges, or small highly loaded details where a sandwich would create more problems than it solves.
Fifth, plan the closeouts and hard points before resin touches fabric. Honeycomb edges can be exposed on flat panels, and those edges need sealing for weatherproofing and appearance. Hard points can be bonded into a honeycomb sandwich, but that means the core selection and insert design are joined decisions. If you choose honeycomb but have no plan for the edge and no plan for the bolt load, you have not chosen a usable construction. You have only chosen a material sample.
Sixth, define the evidence. Professional teams test composite coupons, complete components, suspension links, corner assemblies, and even whole cars under static, dynamic, repeated, and environmental loads. That does not mean every club-level panel needs a servo-hydraulic machine. It does mean safety-critical parts deserve a higher evidence standard than a nice-looking cured panel. If the part is an aerofoil mount, suspension part, tub structure, crash structure, or any component whose failure can hurt the driver or another car, the selection is incomplete without proof testing, qualified design help, or a conservative decision not to build it that way.
Core families and where they fit
Rigid and flexible foams are the practical starting point for many workshop sandwich jobs. The corpus supports foam use especially where a large component lacks enough rigidity from its shape, and where curved areas require a core that can conform. PVC foam is named as a flexible foam choice for curved sandwich work. The lesson is not that foam is always weak or always safe. The lesson is that foam is often the buildable answer when the geometry would make a rigid honeycomb awkward, when the part is a body panel or duct rather than a primary safety structure, and when the builder needs a core that can be laminated cleanly with home-workshop methods.
Coremat sits in a different practical slot. It is useful when you need a curved or awkward sandwich effect without chasing the lightest possible result. The important caution is that Coremat absorbs resin. Because of that resin absorbency, it does not produce the lightest laminate. Its value is that it can still produce a lighter and stiffer laminate than simply making the same thickness from chopped-strand mat. That makes Coremat a useful middle-ground answer for bodywork, ducting, covers, and other non-primary structures where a simple thick laminate would be heavy and limp, but a high-end honeycomb solution would be fussy or unnecessary.
Aluminium honeycomb is a high-value tool and a high-consequence choice. In professional competition cars, carbon-skinned aluminium honeycomb is typical for monocoque chassis construction, and honeycomb is used in both stressed and unstressed components. Aluminium honeycomb can also be excellent in an impact absorption structure, particularly in the form described with aluminium sheet skins, because once it has done its job it is disposable. That last word matters. A crushable impact member is not a permanent spring. If it absorbs energy by crushing, it has consumed its value and must be treated as a replace-or-rebuild part.
Aramid paper honeycomb, commonly referred to as Nomex, occupies another slot. It is expensive, low density, stable, inherently fire retardant, fatigue resistant, and strong against hostile environments such as corrosion and high temperature. It also has a better strength-to-weight ratio than commercial-grade aluminium honeycomb, while not being as stiff per unit weight as aluminium honeycomb. That trade matters. If you need the highest stiffness per weight in a flat panel, aramid paper honeycomb may not be the winning answer. If you need low density, fire resistance, fatigue resistance, and environmental durability, it may be a much more serious candidate.
Woven E-glass honeycomb coated with cured phenolic resin gives a different blend. It is described as offering the same strength-to-weight ratio as aerospace aluminium honeycomb, with lower stiffness per unit weight, but better stiffness-to-weight ratio than aramid paper honeycomb. That means it is not simply a cheap substitute for aluminium or Nomex. It is another point on the map: strength, stiffness, weight, environment, cost, and availability all move relative to one another.
Carbon fibre honeycombs also exist, coated with different resins. The bond does not provide enough detail to teach exact selection between carbon honeycomb products, so treat that family as a specialized option rather than a default. When a corpus gives only the existence of a material and not its working limits, do not pretend you have a design table.
Pre-manufactured flat sandwich boards can be valuable when the part is truly a flat-board problem. They can come with aluminium honeycomb, aramid paper honeycomb, or polyurethane foam cores, and with skins ranging from glass FRP through aluminium sheet to carbon FRP. They can provide a relatively simple way to build an extremely strong, stiff, effective structure. The boundary is that the fabrication of complete structures such as a race-car chassis lies beyond simple workshop panel selection. Use flat board when the geometry, edge treatment, attachments, and rules match the board. Do not use it as an excuse to improvise a safety cell.
The attachment problem: cores hate point loads unless you design the transition
Most core-selection mistakes show up at the places where the sandwich stops being a nice panel and starts becoming a car part. The panel needs a bolt. The panel needs a bracket. The panel ends at an edge. The panel meets a tube, a hinge, a splitter strut, a wing support, a floor stay, a seat mount, or a latch. At those points, the core is no longer just spacing and shape. It is next to a concentrated load, and concentrated loads are where casual sandwich work gets ugly.
For honeycomb edges, the basic requirement is clear: push the honeycomb back from the edge, fill the gap, and sand the filler flush with the laminate edges so the panel is weatherproof and presentable. That is not decorative fussing. If the core is exposed, the environment has a path into the structure, and the exposed cells are mechanically vulnerable. Edge closeout is part of the core choice, not a later cosmetic operation.
For hard points, start with the load path. A hard point bonded into a honeycomb sandwich is a recognized construction, but it must be designed as a hard point. If the part needs a fastener, you must decide whether the surrounding core is removed, filled, reinforced, replaced, or bridged by a local insert. The corpus does not give a universal insert recipe, so do not invent one. The teachable rule is this: if the part needs a point load, the core decision is not finished until the hard point and its bond are specified and testable.
Professional adhesive practice is a useful warning. Composite suspension pushrods with bonded metallic joints have used specialized adhesives good enough that confidence can approach welded-joint confidence. But that confidence comes with proof tests, ultimate tests, coupons, controlled attachments, and the expectation that normal service loads stay below breaking loads. You do not get that confidence from adhesive brand reputation alone. If your home-built sandwich has a bonded bracket that would be dangerous if it left the car, treat the bracket and the core transition as a test problem.
The impact problem: toughness is not the same as stiffness
A stiff core can make a part feel convincing in your hands and still be wrong for impact. McBeath's material discussion gives two important impact lessons. First, carbon may not be the wisest choice for a nosecone, while aramid or carbon/aramid hybrid can be better. Second, honeycomb's tendency to crush gradually can make it useful in race-car impact structures, because progressive crushing can absorb energy and reduce deceleration severity.
Those two lessons pull in the same direction: if the part may hit something, ask how it should fail. A splitter rub strip, a nose corner, a wheel-arch edge, a tub side, a sidepod, and a wing endplate all face different contact situations. Some need abrasion resistance. Some need crush. Some need ductility. Some need to keep fragments contained. Some should be sacrificial. Some should not be built by you without qualified design support.
This is where the high-stiffness trap appears. Ultra-high-modulus carbon can engineer very high stiffness into a laminate, but it can also make brittle components if used overzealously where toughness and forgiveness are needed. That warning is not limited to fiber selection. It also applies to core selection. A very stiff flat sandwich can be the wrong answer when the part needs abuse tolerance, crush behavior, repairability, or survival after contact.
Impact structures also have a boundary. Regulatory bodies and professional designers keep reviewing impact absorption and loading capacity, and there is an acknowledged argument that some structures help only at particular impact angles. For an intermediate builder, that should produce humility. A core that crushes nicely in one direction is not a universal safety system. If the job is driver protection, wheel intrusion resistance, or a primary crash load path, you are outside casual fabrication and inside engineered structure.
The environment problem: heat, water, corrosion, fatigue, and handling all count
Environment is not a separate concern you add after the part is built. It is one of the reasons to choose one core over another. Aramid paper honeycomb earns attention partly because of low density, stability, fire retardance, fatigue resistance, and hostile-environment resistance including corrosion and high temperature. Test equipment used by professionals can place samples in high-temperature environmental chambers to evaluate parts that must function in hot areas. That testing practice exists because composites and bonds do not live in a clean room once installed on a car.
For bonded and pre-preg work, contamination also belongs in the environment column. Epoxy resins absorb moisture, and bond strength is reduced in the presence of water. Skin oils impair bond strength. Pre-pregs can also lose tack and workability during out-life and may not re-flow properly during cure, leaving weaker internal bonding. That belongs mostly to the pre-preg and cure lessons, but it matters here because a core choice that requires a high-quality bond is only as good as the handling route that can produce that bond.
A practical core-selection card therefore includes four environment questions. Will the part see heat? Will it see water or spray? Will it have exposed edges? Will the chosen process expose the bond to moisture, skin oil, old pre-preg, or uncontrolled cure? If the answer to any of those is yes, the core family must be judged on environment and process reliability, not just stiffness and weight.
The regulation and budget problem
Before you fall in love with a material, check the rules. Motorsport categories can restrict permitted composite materials, and building a light part from a banned material is wasted work. Budget also shapes appropriate application. Some categories and home-built specials make extensive composite use possible. Other categories make expensive fibers a poor fit. The correct choice is not the most advanced material you can name. It is the most suitable legal material you can build, inspect, maintain, and replace.
This is especially important for intermediate builders because composite materials are seductive. A woven carbon skin over honeycomb looks serious. A Nomex honeycomb panel sounds advanced. A carbon/aramid hybrid has professional credibility. None of that matters if the class forbids it, the part cannot be inspected after a strike, the edge cannot be sealed, the hard point is not supported, or the budget prevents replacing a disposable impact piece after it has done its job.
The professional comparison is useful only if you copy the decision logic, not the parts list. Formula 1 uses carbon and aramid over honeycomb for panels, carbon over aluminium honeycomb for chassis, and carbon suspension links. Indycars have used heavier chassis structures with the possibility of oblique wall contact in mind. Those examples show that professional composite choices are tied to rules, crash assumptions, load cases, and test capacity. They do not say that a club builder should build every panel from the most exotic stack available.
Calibration cues: how you know the choice is getting better
Good core selection feels less like material shopping and more like risk sorting. You know you are improving when your notes name the part by zones instead of as one vague item. You have a different answer for the flat center than for the curved return. You know where the core stops. You know how the edge closes. You know whether a hard point is bonded into the sandwich, isolated from it, or supported by a local change. You know why the part is allowed to crush, or why it must not crush. You know whether the part is legal. You know what evidence you need before use.
For a stiffness-driven panel, good looks like avoiding brute-force laminate thickness. If the area is large and flat and has little natural rigidity from shape, sandwich construction is on the table. If the curve is tight, the core conforms without bridging or forcing the laminate into a bad lay-up. If Coremat is chosen, you accept that it is resin absorbent and not the lightest path, and you choose it because it beats a thick CSM-only solution in that job. If honeycomb is chosen, the edge and insert plan is drawn before lay-up.
For an impact-driven part, good looks like naming the energy path and the replacement plan. Aluminium honeycomb used as an impact absorber is disposable after doing its job. Honeycomb used for progressive crush is not judged by whether it remains pretty after the hit. A nose or contact-prone part is not automatically carbon because carbon is fashionable. You consider aramid or hybrid reinforcement where toughness, fracture resistance, or abrasion behavior is the reason.
For an environment-driven part, good looks like matching the core family and process to heat, moisture, fatigue, and corrosion exposure. If the part lives near heat, you do not treat room-temperature shop stiffness as proof. If the core has exposed cells, they are closed. If the bond depends on clean pre-preg or adhesive behavior, you respect moisture, skin oil, and out-life limits. If the environment is beyond your evidence, you step back.
For a safety-critical part, good looks like evidence. Professional testing may include tensile, compressive, flexural, shear, peel, tear, fatigue, proof, ultimate, compression-after-impact, and environmental testing. Your workshop may not own those machines, but that does not lower the part's need. It lowers what you should attempt. If the consequence of failure is high and the evidence is weak, the correct core choice may be to stop, buy a qualified part, or ask a professional.
A usable checklist before you commit
Before cutting core, answer these questions in writing. What is the part? What zones does it contain? Which zones are flat enough to need sandwich stiffness? Which zones are curved enough to need foam, Coremat, or no core? Which zones may see impact, abrasion, or crush? Which zones see heat, moisture, corrosion risk, fuel, oil, or repeated fatigue? Where are the free edges? Where are the fasteners, inserts, or bonded brackets? What regulation limits the material? What will you do to prove the part before use?
The answer does not need to be academic. It needs to be honest. A good answer can be short: flat floor panel, honeycomb candidate, closed edges required, no point loads without inserts, class rules checked, not a crash structure, sample closeout built first. A bad answer can be long and still useless: carbon because light, honeycomb because stiff, adhesive because strong, probably fine.
For intermediate work, the craft is not knowing every material property by memory. The craft is refusing to collapse different requirements into one word like stiff or light. Core choice is the disciplined act of matching geometry, stiffness, impact, environment, bonding, rules, and evidence before the laminate locks your decision in place.
Worked example: a hillclimb nosecone that is not a tub
McBeath's hillclimb and sprint-car example is a useful club-level model because it is not pretending to be a Formula 1 tub. The Mallock-style narrow nosecone was patterned from MDF, polyurethane foam block, and body filler. The finished nosecone was made from glass chopped-strand mat and woven carbon, with local stiffeners. That example teaches restraint. The part needed shape, bodywork stiffness, and local reinforcement. It did not automatically become a full honeycomb chassis structure just because advanced composites existed.
Now imagine you are choosing core for your own nose or front body section. Start by zoning it. The broad upper surface may be large enough and flat enough to need sandwich help. A curved side return may not accept a stiff flat core cleanly. A tight radius near the intake may prefer flexible foam, Coremat, or no core rather than a forced honeycomb. A mounting flange may need solid laminate or a local hard point rather than core under a bolt. A front corner that may touch cones, bodywork, a kerb, or another car needs toughness and repairability, not just stiffness.
The corpus gives a specific warning here: carbon may not be the wisest nosecone choice, while aramid or carbon/aramid hybrid can be better. You should read that as a job statement. Nosecones are exposed. They can be hit. They can scrape. They can need to hold together after local damage. If you choose a high-stiffness carbon skin and a delicate core everywhere, you may build a part that feels excellent in the paddock and behaves badly when abused.
A good intermediate answer for a club-level nose is therefore mixed and local. Use sandwich only where the panel size and shape justify it. Use a conformable core where the shape requires it. Use local stiffeners where the load is local. Treat mounts and edges as separate design details. Consider aramid or hybrid reinforcement in contact-prone areas when the job is toughness. Avoid copying a professional tub stack into a body panel whose real survival job is shape, lightness, local stiffness, and survivable contact.
Worked example: professional tub logic versus club-car bodywork
Formula 1 and Indycar examples are useful because they show how strongly core choice follows the load case. Formula 1 body panels have used carbon or aramid over honeycomb, chassis have used carbon over aluminium honeycomb, and suspension links have been made from carbon fibre. Indycar chassis philosophy has accepted heavier structures because the cars may have oblique impacts with concrete walls at high speed. Those are not style choices. They are load, rule, safety, and evidence choices.
The professional lesson is not to put aluminium honeycomb in every part you build. The professional lesson is to ask why the professional part used it. A carbon-skinned aluminium honeycomb chassis needs torsional stiffness and structural capacity. A body panel over honeycomb may need light stiffness and controlled shape. An impact structure may use honeycomb because it crushes gradually. A suspension link may need autoclave-level consistency, specialized adhesives, coupon evidence, and proof testing before anyone trusts it. The material label is only the surface of the decision.
For your own club car, that comparison keeps you from two opposite errors. The first error is fear: assuming all useful sandwich work is beyond a home workshop. The corpus does not support that fear. Composite techniques have filtered down, wet lay-up remains useful, and foam or Coremat sandwich work can be practical. The second error is imitation: assuming that because a top-level car uses honeycomb and carbon, your untested splitter mount, seat bracket panel, or wing support is now professional. The corpus does not support that either. Quality standards for safety-critical links and aerofoil mounts are high, and parts can be rejected even in professional production.
Use the professional examples as a decision mirror. If your part is a flat non-critical panel, a pre-made sandwich board or simple foam-core panel may be reasonable. If your part is a crash structure, driver-protection structure, suspension link, or high-load aero mount, the professional example should raise the evidence requirement rather than lowering your caution.
Common mistakes: what wrong looks like and what good looks like
Mistake one is choosing the stiffest core and calling the job done. Wrong looks like a panel that is impressively rigid in your hands but brittle, hard to repair, poorly suited to impact, or unsupported at the mounts. Good looks like choosing stiffness only where stiffness is the primary job, and checking whether toughness, crush, attachment, environment, or legality is more important in another zone.
Mistake two is forcing a flat-core solution into a curved shape. Wrong looks like honeycomb or rigid core fighting the mould, bridging, opening gaps, or making you compensate with excess resin and pressure. Good looks like recognizing when flexible PVC foam, Coremat, or a different local construction fits the shape better than a high-status material.
Mistake three is treating Coremat as magic lightness. Wrong looks like choosing it because it sounds like core, then being surprised by resin weight. Good looks like choosing Coremat knowingly: it absorbs resin and is not the lightest laminate, but it can still beat an equivalent thickness of chopped-strand mat for a lighter, stiffer practical panel.
Mistake four is leaving honeycomb edges as an afterthought. Wrong looks like exposed cells at the panel edge, rough filler added after the fact, or water and debris paths into the core. Good looks like a designed edge closeout: core set back, gap filled, surface sanded flush, and the edge treated as part of the structure's weatherproofing and finish.
Mistake five is drilling a hard point through a sandwich as if it were solid plate. Wrong looks like a bolt, bracket, or insert crushing core, peeling skins, or concentrating load into a small unsupported area. Good looks like a hard-point plan before lay-up: local reinforcement, insert strategy, bond plan, and evidence appropriate to the consequence of failure.
Mistake six is copying professional materials without professional controls. Wrong looks like carbon honeycomb or high-modulus materials used because they look serious, while cure, contamination, coupon, proof, and impact evidence are missing. Good looks like copying the professional decision logic instead: location-specific material choice, process control, realistic load assumptions, and rejection of parts that cannot be proven.
Mistake seven is ignoring the rulebook until after the part is beautiful. Wrong looks like a banned carbon or exotic composite part arriving at scrutineering. Good looks like checking permitted materials before buying core, especially in cost-controlled or class-limited categories.
Mistake eight is using an impact absorber as if it were reusable. Wrong looks like continuing to run a crushed honeycomb structure because the skins still look acceptable. Good looks like treating disposable crush structures as consumed after they have done their job.
Drill: the three-zone core-selection card
Do this before your next fabrication session, using a real part you intend to build or repair. The drill takes about 60 to 90 minutes. The count is three zones, two sample details, and one go/no-go decision.
Pick one candidate part and draw it large enough to mark up. Choose three zones: one broad flat area, one curved or returned area, and one edge, mount, or hard-point area. For each zone, write the primary job in one sentence. Use only one primary job per zone: stiffness, shape conformity, impact or abrasion survival, hostile-environment survival, or attachment support. If you cannot choose one, split the zone smaller.
Next, assign a candidate construction to each zone. The flat area might be foam, honeycomb, pre-made sandwich board, or no core. The curved area might be flexible foam, Coremat, or solid laminate. The edge or hard point might require the core to stop, a filled closeout, a bonded insert, or local solid reinforcement. Write why the candidate was chosen and what would make it wrong.
Then build two sample details before touching the real part. One sample must be an edge closeout or core termination. The other must be either a curved-core lay-up sample or a hard-point mock-up, depending on which is riskier in your part. The samples are not proof for a safety-critical component. They are a fabrication check: can you make the core conform, close the edge, control resin, and produce the detail you drew?
The success criterion is not that the samples look pretty. The success criterion is that you can answer five questions without hand-waving: why this core in this zone, how the edge or hard point is handled, what impact or environment it must survive, what rule or budget limit applies, and what evidence is required before the part goes on the car. If any answer is vague, revise the core choice before laminating the actual part.
When this principle breaks down
This lesson gives you a selection method, not permission to design every structure. The principle breaks down when the part's consequence of failure is higher than your evidence. Suspension links, primary chassis structures, driver-protection structures, high-load wing mounts, and serious impact structures need more than a sensible core family. They need design calculation, controlled manufacturing, proof or ultimate testing, fatigue consideration, environmental evaluation, and quality standards.
It also breaks down when the corpus or supplier data does not define the limit you need. If all you know is that a material exists, you do not know enough to design a critical part from it. If you know a core has good strength-to-weight but not enough stiffness for your job, you do not pretend otherwise. If you know a honeycomb crushes progressively in one kind of impact, you do not assume all-round crash protection. If the rules may ban the material, you do not build first and ask later.
The correct recovery is not to add more exotic material. The recovery is to reduce the job, choose a less critical use, buy a qualified component, consult someone who can analyze and test it, or refuse the build. In composites, stopping before the lay-up can be the highest-skill move in the whole job.
Author Review
No quiz questions are attached to this lesson.
Sources
| # | Document | Chunk | Pages | Score | Collection |
|---|---|---|---|---|---|
| 1 | Competition Car Composites Simon McBeath | 72a09638-247f-f527-1a53-3716fd2956eb | 42 | 1 | uio_books_raw_v1 |
| 2 | Competition Car Composites Simon McBeath | 194efe34-01b3-87b6-6edd-9e14be46972c | 107 | 1 | uio_books_raw_v1 |
| 3 | Competition Car Composites Simon McBeath | 2afc9093-4cdd-d995-d340-aac602fd741a | 176 | 1 | uio_books_raw_v1 |
| 4 | Competition Car Composites Simon McBeath | 33166f0f-e752-e86b-241d-4a2c998ac3c2 | 176 | 1 | uio_books_raw_v1 |
| 5 | Competition Car Composites Simon McBeath | 91fc949d-da8a-17a1-0b8f-4c19973de30f | 168 | 1 | uio_books_raw_v1 |
| 6 | Competition Car Composites Simon McBeath | 6517b923-9f62-7638-e6e1-0d93afa10f8f | 177 | 1 | uio_books_raw_v1 |
| 7 | Competition Car Composites Simon McBeath | 50e8919c-ef19-4354-dea8-95d9c311c69e | 178 | 1 | uio_books_raw_v1 |
| 8 | Competition Car Composites Simon McBeath | 0417d4d8-2df3-87dd-a347-0684c8b7e5b5 | 178 | 1 | uio_books_raw_v1 |
| 9 | Race Car Engineering Mechanics Paul Van Valkenburgh | ca7a3241-be1f-1f6f-b111-5291d7865790 | 96 | 1 | uio_books_raw_v1 |
| 10 | Race Car Engineering Mechanics Paul Van Valkenburgh | 42822437-0d05-600a-9e1e-967d20b17f67 | 99 | 1 | uio_books_raw_v1 |
| 11 | Competition Car Composites Simon McBeath | 2b41f8db-cdd5-e584-d3e8-3cb469eea226 | 198 | 1 | uio_books_raw_v1 |
| 12 | Competition Car Composites Simon McBeath | b62835e2-37fe-36d0-af44-3b5152d14917 | 184 | 1 | uio_books_raw_v1 |
| 13 | Competition Car Composites Simon McBeath | 781f8145-6150-097b-9c36-0cf693583e67 | 202 | 1 | uio_books_raw_v1 |
| 14 | Competition Car Composites Simon McBeath | 646b6c1d-94be-1ae4-077f-baa8a3c089ab | 154 | 1 | uio_books_raw_v1 |
| 15 | Competition Car Composites Simon McBeath | 4cd165c8-25b6-009a-f4b5-4fae9a62b8dc | 12 | 1 | uio_books_raw_v1 |
| 16 | Competition Car Composites Simon McBeath | a0cc1d08-7515-9bbc-fe01-3d5ebc6719bb | 11 | 1 | uio_books_raw_v1 |