Home › Blog › Structural Bonding & Fastener Replacement › How to spec a bonded joint
How to Spec a Bonded Joint: What to Send H-O for a Quote
A fast, accurate quote on a custom die-cut bonded joint comes down to a handful of inputs: the job the part does, both substrates and their surface condition, the bond-line thickness or gap, whether the load is static or dynamic, the temperature and environment, whether the joint must be removable, the die-cut geometry, and your prototype and annual volumes. This guide walks each input, explains why it matters, and ends with a spec builder that assembles your answers into a request you can paste straight into the quote form.
One thing it deliberately does not do is hand you a final shear allowable, because that belongs to a test of your actual joint.
Request a quote for your project →
The application problem: an incomplete spec stalls the quote
H-O Products is a precision die-cut converter, and every bonding part is made to order from sheet, roll, or slab stock cut to your drawing. The concrete problem a buyer runs into is the stalled quote: a request that says "I need a structural bonding tape" without the substrates, the load type, or the bond-line gap cannot be turned into a family, a grade direction, and a price without a follow-up.
The inputs below are the same ones an applications engineer would ask for, so sending them up front turns a back-and-forth into a single response.
The first input does the most work. As covered in the companion guides on choosing between bonding and fastening and on surface energy and load type, the part is doing one of a few jobs: a structural bond that replaces welds, rivets, and fasteners; a glazing bond and seal of glass or a panel to a frame; a thin attachment of a display, lens, or nameplate; or a temporary fixture that has to release cleanly. The rest of the spec branches from that answer.
Why it is challenging: the inputs come in pairs and the joint owns the allowable
Specifying a bonded joint is harder than listing dimensions because two of the most important inputs are pairs, not single numbers, and because the final strength belongs to the assembly rather than the tape. You have to give both substrates, not one, because the bond forms at two interfaces and the harder of the two surfaces to wet drives the adhesive choice.
You have to state both the static and the dynamic load, because a sustained hold is governed by creep and holding power while a vibrating or cycling load is governed by the foam core's ability to absorb movement, and the two are sized differently. And a shear allowable is a result the actual joint earns in a test under real substrates, preparation, dwell, temperature, and loading mode, not a property you can read off a datasheet, so the spec has to separate what the part is from what the joint must prove.
The checklist below is organized around those realities.
What to send, input by input
1. The job
Say which job the part does: structural bond, glazing bond and seal, thin attachment, or temporary fixture. This sets the family direction before any number is discussed, because a structural bond points at acrylic foam tape, a glazing bond at glazing tape read against the ASTM C1184 framework, a thin attachment at a transfer tape, and a temporary fixture at a clean-release rubber adhesive that is not structural.
2. Both substrates and their surface condition
Name the material on each face, and flag the surface condition. The decisive flag is whether either surface is low surface energy, polypropylene, polyethylene, TPO, or powder-coated, because a standard acrylic will not wet it and a low-surface-energy adhesive or NetBond acrylic grade is needed instead. Also note whether a surface is oily, contaminated, painted, or freshly treated, since that drives the cleaning and primer decision.
3. Bond-line thickness or gap
Send the bond-line thickness, or the gap the part has to span. This matters because differential thermal expansion between dissimilar substrates needs a foam core thick enough to absorb the shear strain. Too thin a core for the movement fatigues the bond, so the thickness is part of the spec, not a leftover.
4. Static and dynamic load
State the sustained (static) load the joint holds and any dynamic load it sees, vibration, wind, thermal cycling, or panel flutter. The static case is sized with margin against creep and verified by holding power per ASTM D3654; the dynamic case relies on the viscoelastic core to absorb movement. Sending only one leaves the sizing half-specified.
5. Temperature and environment
Give the service temperature range and the environment, indoor, outdoor, UV, moisture, cleaning chemistry, or road spray. Hot or severely exposed service points toward a silicone-acrylic combination that widens the temperature and weather range beyond a plain acrylic.
6. Removability
Say whether the joint is permanent or must come back apart. A permanent structural bond points at acrylic foam tape; a clean-release or temporary-fixture need points at a rubber adhesive, which trades sustained-load capacity and UV stability for removability and is not a structural bond. Naming this up front avoids specifying a permanent tape for a part that has to be serviced.
7. Die-cut geometry
A dimensioned drawing closes the loop. Send a DXF, STEP, or PDF with the outline, the bond-line thickness, any holes, tabs, or pull-tab, kiss-cut callouts on the liner, and tolerances. If you do not have a formal drawing yet, a marked-up sketch with dimensions is enough to start a prototype. Routing the geometry as a continuous strip or frame, rather than scattered pads, also keeps peel low at the edges.
8. Prototype and annual volume
Share both the prototype quantity and the expected annual volume. All parts are custom manufactured to order, and minimum production run quantities apply, so the volume shapes the converting approach and the tooling decision. Prototype quantities through full production are welcome.
The spec at a glance
| Input | Structural bond | Glazing | Thin attachment |
|---|---|---|---|
| Substrates | Both faces + surface energy / condition | Glass / panel + frame | Both faces (usually flat, HSE) |
| Bond line | Thickness / gap to span | Joint width and movement | Thin, close-fitting |
| Load | Static + dynamic both stated | Wind, thermal movement | Light, mostly shear |
| Environment | Temp, UV, chemistry → family | Outdoor, UV, weather | Indoor or controlled |
| Removability | Permanent (or fixture → rubber) | Permanent, read vs. ASTM C1184 | Permanent |
| Commercial | Geometry (DXF / STEP / PDF); prototype quantity + annual volume | ||
Bonded-Joint RFQ Spec Builder
Job: Structural bond (replace welds, rivets, fasteners; load in shear) Substrates: face A and face B — to be provided (flag low surface energy) Bond line: thickness / gap to span — to be provided Geometry: footprint / bond area — to be provided Load: static (sustained) and dynamic (vibration / cycling) — both to be provided Environment: temperature range, UV, chemistry — to be provided Removability: permanent bond Surface prep: standard clean and dry Build: standard die-cut Commercial: prototype quantity + annual volume — to be provided Drawing: to follow Note: shear allowable to be confirmed by qualifying the actual joint
Illustrative only; confirm against current material data and a drawing review. This builder formats your inputs into a request; it does not select a grade, compute a shear allowable, or qualify a joint. Surface-energy fit, shear and peel behavior, service temperature, and holding power are confirmed on the manufacturer's current technical data sheet and by qualifying the actual joint under your real substrates, preparation, dwell, temperature, and loading mode.
Common failure modes in the spec itself
| Spec gap | Why it stalls the quote | The fix |
|---|---|---|
| "A structural bonding tape," no substrates | The family and adhesive cannot be chosen without knowing what is being bonded | Name both substrates and flag any low-surface-energy surface |
| One substrate given, not both | The bond forms at two interfaces; the harder surface to wet drives the choice | Send the material on each face |
| Only a static load, no dynamic | Static is sized against creep; dynamic around movement absorption, sized differently | State both the sustained and the cyclic load |
| Asking for "the shear strength" as the spec | A shear allowable is a tested result of the actual joint, not a single grade number | Send the conditions; qualify the joint by test (ASTM D1002 / D3163, D3330, D3654) |
| No volumes | The converting and tooling approach depends on prototype versus production scale | Send both prototype quantity and annual volume |
How H-O Products helps
H-O Products is a precision die-cut converter. Once your spec is complete, we recommend a material family and grade direction across coated acrylic foam tape and uncoated acrylic foam tape, acrylic transfer tapes and double-coated tapes, glazing tape, and the low-surface-energy and NetBond grades for hard-to-bond substrates, then convert the stock to your drawing: die-cut, kiss-cut, laser or waterjet cut, laminated to substrates, slit to width, and kitted.
Documentation available on request includes the material technical data sheet, a certificate of conformance, lot traceability, and first-article inspection, all under our ISO 9001:2015 certified quality management system. We do not produce the raw stock and we do not certify the finished joint or the glazing system; grade properties are confirmed against the manufacturer's current technical data sheet, and the joint is qualified by testing the actual bond.
Send the spec, get a quote
Use the builder above to assemble your request, then paste it into the quote form with your drawing attached. We will recommend a family and grade direction and convert samples on your footprint.
Samples typically ship in 3 to 5 business days for common die-cut configurations; standard production runs about two weeks; special orders are quoted to the job.
Family-owned in Winsted, Connecticut since 1971 · ISO 9001:2015 certified · OEMs worldwide send us a drawing — and get back their part.
Related reading
Frequently asked questions
What information does H-O need to quote a custom bonded joint?
Send the job (structural bond, glazing, thin attachment, or temporary fixture); both substrates and their surface condition, flagging any low-surface-energy surface such as polypropylene, polyethylene, TPO, or powder-coat; the bond-line thickness or gap to span; the static and the dynamic load; the service temperature and environment; whether the joint must be removable; the die-cut geometry as a DXF, STEP, or PDF; and the prototype quantity and annual volume.
Why does H-O need both substrates, not just one?
A bonded joint forms at two interfaces, one on each face, and the adhesive has to wet both. The harder surface to wet drives the choice, so if either face is a low-surface-energy plastic or a powder-coat, the joint needs a low-surface-energy-formulated adhesive or a NetBond grade regardless of what the other face is. Naming only one substrate leaves that decision open.
Can H-O tell me the shear strength of my bonded joint?
A datasheet reports an apparent lap-shear strength for a standard test specimen, but the allowable for your joint depends on your substrates, surface preparation, dwell, temperature, and loading mode, so it is confirmed by qualifying the actual joint by test (ASTM D1002 or D3163 lap-shear, ASTM D3330 peel, ASTM D3654 holding power). H-O recommends a family and grade direction and converts the part; the finished-joint allowable belongs to your qualification, not to the converter.
Request a quote for your structural bonding & fastener replacement part
Send H-O your drawing or describe the part—engineering reviews every RFQ and converts samples on your geometry.
Last updated · Reviewed by H-O Products engineering (ISO 9001:2015 certified converter, Winsted, CT).
References
- ASTM D1002 and ASTM D3163 (apparent lap-shear strength). ASTM International.
- ASTM D3330 (pressure-sensitive tape peel adhesion) and ASTM D903 (peel or stripping strength). ASTM International.
- ASTM D3654 (shear holding power). ASTM International.
- ASTM C1184 (structural silicone glazing framework). ASTM International.
- Manufacturer technical data sheets: acrylic foam bonding tapes, acrylic transfer tapes, and low-surface-energy adhesive systems.
This article cites general engineering principles and published standards (ASTM D1002 and ASTM D3163 for apparent lap-shear, ASTM D3330 for pressure-sensitive-tape peel adhesion, ASTM D903 for peel or stripping strength of adhesive bonds, ASTM D3654 for shear holding power, ASTM C1184 as the structural-silicone-glazing framework). Material names refer to material families H-O Products converts.
Shear and peel strength, surface-energy fit, and holding power are grade-specific and substrate-specific; confirm all values against the manufacturer's current technical data sheet and an engineering drawing review. All parts are custom manufactured to order and minimum production run quantities apply. H-O is a die-cut converter, not a raw-material producer, and does not certify the finished joint or the glazing system.