Pacer RX-500 Range Extended Cyanoacrylate Adhesive (350-550 cP)

Pacer RX-500 cyanoacrylate adhesive is a virtually non-surface-sensitive instant adhesive that runs 350 to 550 cP and fills to .008 in. It occupies a specific spot in the Pacer line: it is the thickest Range Extended grade available in a 1 lb bulk bottle, which makes it the only option if you need non-surface-sensitive chemistry, real gap capability, and production volume all at once. The RX chemistry bonds porous substrates, acidic substrates, plated parts, and surfaces carrying silicone grease, oil, or release agent, and it fails the substrate before the bond on ABS, rigid PVC, nylon, polycarbonate, SBR, and EPDM. RX-500 meets MIL-A-46050C Type II, Class 3 and A-A-3097 Type II, Class 3.

Key Product Details

Full property data for every grade in the series is in the Pacer RX Series technical data sheet (PDF). The data sheet covers grades beyond what we currently stock. Chemical Concepts carries RX-50, RX-100, RX-500, RX-700, and the RX Gel.

Shear Strength by Substrate

Tested per ASTM D-1002. Where the table reads substrate failure, the part broke before the bond did.

Shear figures are identical across every liquid grade in the RX Series, so stepping up to RX-500 for the wider gap costs you nothing in strength. That is not true in Pacer’s general purpose E Series, where steel shear drops from 2700 psi in the thin grades to 2200 in the thickest.

Setting Up a Cyanoacrylate Bonding Station

Buying a 1 lb bottle is a different decision from buying a 20 gram. You are not just getting more adhesive, you are committing a station to a process, and cyanoacrylate has a few habits worth designing around before you do.

• Decant into applicator bottles rather than working from the bulk container. Move a shift’s worth at a time and keep the 1 lb capped. Pacer does not publish repackaging guidance, so treat this as shop practice and keep transfer containers clean and dry.
• Cure rate tracks relative humidity. A station that runs to spec in July may fixture noticeably slower in a dry heated shop in January. Time your parts in both conditions before you set a takt.
• Design the fixture for a horizontal or clamped joint. At 350 to 550 cP RX-500 is slower to move than a thin grade but it is still a liquid and it will run on a vertical face.
• Set the bond area against 2300 psi on steel or 1600 psi on aluminum rather than the 4000 psi tensile figure. Shear is what most joints actually see.
• One free-falling drop covers about one square inch of bond area. Standardize the drop count per part so operators are not judging it by eye, and remember that over-application weakens the joint rather than strengthening it.
• Plan the accelerator into the station if you are working near the top of the .008 in gap. Pacer recommends accelerators specifically to speed cure through larger gaps, at the cost of possible white frosting on exposed adhesive and some loss of cure strength.
• Keep Pacer X-9 Debonder at the station. Cured cyanoacrylate comes off with X-9 Debonder, acetone, or nitropropane, and the debonder is also what removes accelerator frosting from a finished face.
• Stock a year or less. Shelf life is one year stored per the data sheet, and an opened container works against ambient humidity from day one, so a bulk buy beyond your annual consumption does not save money.
• Even with Range Extended chemistry, clean the parts. Pacer’s guidance still calls for surfaces free from oil and grease. RX-500 gives you process margin, not permission to remove cleaning entirely.

Choosing a Viscosity in the RX Series

Every grade in the RX Series runs the same non-surface-sensitive ethyl hybrid cyanoacrylate chemistry, the same -65F to +180F cured range, and the same shear figures. Viscosity, gap, and package are what change.

Look at the sizes column and RX-500’s position becomes clear. RX-700 is thicker and the gel is thicker still, but neither comes in bulk. RX-100 comes in bulk but fills only .005 in. RX-500 is the only grade in the series that combines a wide gap with a 1 lb bottle, which is why it tends to be the grade a production line settles on.

Two comparisons outside the series. If your parts are clean and you just need a thick general purpose grade, Pacer E-1500 fills .010 in and is also 20 gram only. And if the joint is vertical or overhead, no liquid grade will hold, so use the RX Gel, keeping in mind it is the one grade Pacer does not certify to MIL-A-46050C.

Performance in Production

• The thickest Range Extended grade available in a 1 lb bulk bottle, which is the specific reason production lines land on this grade rather than RX-700 or the gel.
• Bonds through silicone greases, oils, and release agents, and onto plated parts. A documented property, not a technique claim.
• .008 in gap capability, nearly double RX-100, which covers fit-up variation across a production run rather than requiring consistent parts.
• Substrate failure on ABS, rigid PVC, nylon, polycarbonate, SBR, and EPDM. On all six your joint strength is set by the part, not the adhesive.
• 2300 psi on steel, the same as every other liquid RX grade, so the wider gap costs nothing in strength.
• 1400 psi on copper, a figure the general purpose E Series data sheet does not publish at all.
• Fixture in 1 to 5 minutes and 80% of strength in 15 to 30 minutes, the same across the RX Series.
• At 350 to 550 cP it holds position better than the thin grades but it is not a gel. It will still move on a vertical or overhead face, so build the station around a horizontal or fixtured joint.
• A filled .008 in gap cures from the outside in. Allow the longer end of the strength development range before loading a wide joint, and consider an accelerator.
• Cuts surface preparation. Degrease, abrade, and prime steps that exist only to make a standard CA work can often come out of the process, which is labor off every part.

Common Applications

• Production bonding of plated, oily, or mold-released parts with loose fit-up
• Lines needing Range Extended chemistry at volume in a thicker grade
• Uneven or irregular mating surfaces on difficult substrates
• EPDM and SBR rubber, gaskets, seals, and trim
• Polycarbonate and nylon assemblies
• Copper and brass fittings
• Filling shop applicator bottles from bulk
• Feeding automatic dispensing equipment on a bonding cell
• Removing surface preparation steps from an existing bonding process
• Work calling out MIL-A-46050C Type II, Class 3 or A-A-3097 Type II, Class 3

Available Sizes

The 20 gram bottle is sold in case quantity of 10. The 1 lb bottle sells individually. RX-500 and RX-100 are the only two grades in the series offered in a 1 lb.

Related Products

• Pacer RX-100 Range Extended (80-120 cP), thinner at .005 in gap, the other RX grade available in a 1 lb
• Pacer RX-700 Range Extended (600-800 cP), thicker at .010 in gap, 20 gram only
• Pacer RX-50 Range Extended (30-70 cP), the thinnest RX grade, .004 in gap
• Pacer RX Gel, non-sag non-running gel for vertical applications, .020 in gap
• Pacer E-1500 Instant Adhesive (1300-1700 cP), the thickest general purpose grade for clean surfaces
• Pacer Premium Acetone Accelerator, speeds full cure through larger gaps
• All cyanoacrylate instant adhesives

Frequently Asked Questions

What is Pacer RX-500 used for?

Pacer RX-500 is used for bonding parts with loose fit-up whose surfaces a standard cyanoacrylate will not cure on. At 350 to 550 cP it fills to .008 in, and the Range Extended chemistry handles plated parts, porous and acidic substrates, and surfaces carrying oil, silicone grease, or release agent. It is the thickest Range Extended grade available in a 1 lb bulk bottle, which makes it the usual choice for a production line rather than a bench.

What does non-surface-sensitive cyanoacrylate mean?

It means the adhesive still cures on surfaces that would stop a conventional cyanoacrylate. Standard CA cure is inhibited by acidic surfaces and blocked by oily or greasy films, which is why the same bottle can bond one part in seconds and sit wet on another. Non-surface-sensitive grades, which Pacer calls Range Extended, are formulated to bond anyway. RX-500 handles silicone greases, oils, release agents, plated parts, porous materials, and acidic substrates.

How much gap will Pacer RX-500 fill?

Typical gap capability is .008 in, nearly double RX-100 at .005 in. If your parts sit looser than that, RX-700 fills .010 in and the RX Gel allows .020 in, though both are 20 gram packages only. Past .020 in, cyanoacrylate is the wrong chemistry and a two part structural adhesive is the answer.

Which Pacer RX grades come in a 1 lb bottle?

RX-100 and RX-500 only. RX-50 and RX-700 are 20 gram bottle only, and the RX Gel comes in 20 gram and 200 gram tubes. That makes RX-500 the thickest Range Extended grade you can buy in bulk, which is often the deciding factor for a production line.

Is Pacer RX-500 weaker than a thinner RX grade?

No. Every liquid grade in the RX Series publishes the same figures: 2300 psi shear on steel, 1600 on aluminum, 1400 on copper, and 4000 psi tensile on steel. Stepping up to RX-500 for the wider gap costs nothing in strength. That is different from Pacer’s general purpose E Series, where steel shear drops from 2700 psi in the thin grades to 2200 in the thickest.

Does Pacer RX-500 bond EPDM rubber?

Yes. In ASTM D-1002 testing RX-500 gives substrate failure on EPDM, meaning the rubber tears before the bond does, and SBR is the same. Pacer’s general purpose E Series grades reach only 100 psi on EPDM. For rubber gaskets, seals, and trim at production volume, this is the grade to look at first since it is the thick RX option available in bulk.

Will Pacer RX-500 stay put on a vertical surface?

Better than the thin grades, but it is not rated for it. At 350 to 550 cP RX-500 moves more slowly than RX-50 or RX-100, and Pacer publishes no sag or slump figure for it. The RX Gel is the only grade in the series Pacer rates as non-sag and non-running for vertical applications. Note that the gel is also the only grade not certified to MIL-A-46050C, so if your job calls out that spec and the part is vertical, call us.

Does Pacer RX-500 meet MIL-A-46050C?

Yes. Pacer lists RX-500 as meeting MIL-A-46050C Type II, Class 3 and A-A-3097 Type II, Class 3. Class 3 covers the thicker viscosity band, which is why RX-700 carries the same class while RX-100 is Class 2 and RX-50 is Class 1. If your job needs a certificate of conformance, ask for it when you order.

How should Pacer RX-500 be stored, and what is the shelf life?

Refrigerate unopened bottles for optimal results. Once opened, store in a cool, dry location away from heat sources. Stored that way, expect a one year shelf life.

Questions on Fit

Got a part a standard cyanoacrylate won’t bond? Call (800) 220-1966 or email [email protected] and tell us what the surface has been through.