Pacer E-5 Ultra-Low Viscosity Cyanoacrylate Adhesive (2-10 cP)

Pacer E-5 cyanoacrylate adhesive is a water-thin single component ethyl cyanoacrylate that runs 2 to 10 cP and fills to .002 in. It’s the thinnest grade in Pacer’s General Purpose E Series, and it works differently from the rest of the family: instead of applying adhesive and then closing the joint, you assemble the parts first and let E-5 pull itself into the seam by capillary action. That makes it the grade for press-fit and slip-fit parts, hairline cracks, and anything already together that you don’t want to take apart. It also gives the highest tensile shear on steel in the series at 2700 psi, because a thin bond line is a strong bond line. E-5 meets MIL-A-46050C Type II, Class 1 and A-A-3097 Type II, Class 1.

Key Product Details

Full property data for every grade in the series is in the Pacer E Series technical data sheet (PDF). The data sheet covers grades and package sizes beyond what we currently stock. Of the E Series, Chemical Concepts carries E-5, E-40, E-100, and E-1500.

Tensile Shear Strength by Substrate

Tested per ASTM D1002. Where the table reads substrate failure, the part broke before the bond did.

How Wicking a Cyanoacrylate Works

A wicking grade is applied after the parts are together, not before. At 2 to 10 cP E-5 has roughly the flow of water, so capillary action pulls it into a tight seam on its own. That’s the opposite of the normal CA sequence and it’s what makes this grade useful.

• Clean both faces before assembly. Oil, grease, mold release, and cutting fluid all block the bond, and once the parts are together you cannot get at the joint to clean it.
• Assemble the parts and position them where you want them. The joint needs to be closed and in final alignment before any adhesive goes on.
• Touch a drop to the edge of the seam. Capillary action draws it in along the joint line. One free-falling drop covers roughly one square inch of bond area.
• Watch where it travels. Water-thin CA does not stop at the joint you aimed it at. Keep it away from threads, bearings, bushings, and cosmetic faces, and mask when you need to.
• Work flat where you can. On a vertical or overhead seam E-5 runs down the part rather than staying at the joint.
• Let it fixture for 1 to 5 minutes before handling, and give it 15 to 30 minutes to reach 80% of full strength before loading the joint.
• For a gap wider than .002 in, wicking will not bridge it. Step up a grade instead of adding more adhesive.

Fixture and full cure both move with temperature, relative humidity, bondline thickness, and the substrate pair. Test on actual parts before you lock in a production process.

Choosing a Viscosity in the E Series

All four grades are the same ethyl cyanoacrylate chemistry. Viscosity is what changes, and it drives how much gap you can bridge and whether the adhesive stays put.

Steel shear runs highest at the thin end of the series, which is worth knowing if you have the fit-up to use it. For a true gel that will not move at all on an overhead joint, see Pacer RX-50M Gel. For porous, acidic, or contaminated substrates where any standard cyanoacrylate struggles, Pacer’s RX Range Extended series is the non-surface-sensitive alternative at the same viscosities.

Performance in Production

• At 2 to 10 cP E-5 wicks into a closed joint by capillary action, which lets you align and clamp the part first and bond it second. On press-fit and slip-fit assemblies that removes a whole step.
• 2700 psi tensile shear on steel is the highest in the E Series, matched only by E-40 and well above E-100 at 2400 and E-1500 at 2200. If your parts fit tightly enough to use a wicking grade, you get the strongest steel joint in the family.
• .002 in gap capability means fit-up has to be genuinely close. This grade bridges nothing. Loose parts need E-40 or E-100.
• Fixture in 1 to 5 minutes and 80% of strength in 15 to 30 minutes, the same as the rest of the E Series.
• Plan for migration. Water-thin CA travels along seams, into threads, and onto finished faces, and it will run straight down a vertical surface. Fixture flat, mask what matters, and use less than feels right.
• 15% volume shrinkage and M 75 hardness are both the highest in the series, and elongation is under 2%. This is a hard, rigid, brittle bond. It is not the pick for joints that flex, peel, or see sustained vibration.
• Zero outgassing at 10^-6 mmHg, 8.6 x 10^12 ohm-cm volume resistivity, and a 3.98 dielectric constant. The resistivity and dielectric figures are the highest in the E Series, which matters on vacuum and electrically sensitive assemblies.
• Available in a 5 gram bottle, the only grade in the current E Series offered that small, which suits precision work and trial quantities.

Common Applications

• Wicking into close-fitting joints after assembly
• Press-fit and slip-fit part retention
• Hairline crack repair in plastic and ceramic
• Small metal part bonding on steel and aluminum
• Rubber to metal and rubber to plastic bonding on tight-fitting parts
• Bonding assemblies you cannot take apart to apply adhesive
• Bottle dispensing at the bench or feeding automatic equipment
• Work calling out MIL-A-46050C Type II, Class 1 or A-A-3097 Type II, Class 1
• Vacuum and electrically sensitive assemblies, based on the published outgassing and resistivity data

Available Sizes

The 5 gram bottle is sold in case quantity. Call us if you need a single bottle for a trial and we’ll work something out.

Related Products

• Pacer E-40 Instant Adhesive (30-70 cP), one step thicker, .004 in gap, highest tensile and impact in the E Series
• Pacer E-100 Instant Adhesive (80-120 cP), general purpose middle grade, .005 in gap
• Pacer E-1500 Instant Adhesive (1300-1700 cP), thickest grade in the E Series, .010 in gap
• Pacer RX-50M Gel, a true gel for vertical and overhead joints
• Pacer Premium Acetone Accelerator, speeds full cure through larger gaps
• All cyanoacrylate instant adhesives

Frequently Asked Questions

What is Pacer E-5 used for?

Pacer E-5 is used for wicking into close-fitting joints that are already assembled. At 2 to 10 cP it flows about like water, so you position and clamp the parts first, then touch a drop to the seam and let capillary action pull it in. That makes it the grade for press-fit parts, slip fits, hairline cracks, and anything you can’t take apart to apply adhesive. It’s sold in 5 gram, 20 gram, and 1 lb bottles.

What does wicking grade cyanoacrylate mean?

A wicking grade is a cyanoacrylate thin enough to be drawn into a closed joint by capillary action, so it goes on after assembly instead of before. Wicking grade, penetrating grade, water-thin CA, and thin super glue all describe the same thing. The tradeoff is that it bridges no gap at all, so your parts have to fit within about .002 in.

How much gap will Pacer E-5 fill?

Typical gap capability is .002 in, the tightest in the E Series. A wicking grade has no body, so it will not bridge a visible gap and adding more adhesive does not help. If your parts do not fit that closely, move up to E-40 at .004 in, E-100 at .005 in, or E-1500 at .010 in.

What materials does Pacer E-5 bond?

Pacer E-5 bonds plastics, rubber, metal, and ceramic. In ASTM D1002 testing it gives 2700 psi tensile shear on steel and 1600 psi on aluminum, and on ABS, nylon, rigid PVC, and SBR the substrate fails before the bond does. EPDM comes in at 100 psi. For porous, acidic, or contaminated surfaces, Pacer’s RX Range Extended series is the non-surface-sensitive option.

Is Pacer E-5 stronger than a thicker cyanoacrylate?

On steel, yes. E-5 gives 2700 psi tensile shear against 2400 for E-100 and 2200 for E-1500, because a thinner bond line carries load better than a thick one. That only holds if your parts fit closely enough for a wicking grade to work. A thin adhesive in a loose joint is weaker than a thick adhesive in the same joint, so match the grade to the fit-up rather than picking on the strength number alone.

Will Pacer E-5 run on a vertical surface?

Yes, more than any other grade in the series. At 2 to 10 cP this is essentially the viscosity of water and it will run straight down a vertical face and wick into places you did not intend. Fixture the part flat, mask cosmetic surfaces, and keep it clear of threads and bearings. For vertical or overhead work use E-1500, or RX-50M Gel if it cannot move at all.

Does Pacer E-5 meet MIL-A-46050C?

Yes. Pacer lists E-5 as meeting MIL-A-46050C Type II, Class 1 and A-A-3097 (Commercial Spec) Type II, Class 1. Class 1 covers the thin viscosity band, which is why E-40 also falls under Class 1 while E-100 is Class 2 and E-1500 is Class 3. If your job needs a certificate of conformance, ask for it when you order.

How should Pacer E-5 be stored, and what is the shelf life?

Refrigerate unopened bottles at 40F (4C) for best results, then let the adhesive come up to room temperature before opening. Opening a cold bottle pulls condensation into the material. Once opened, store in a cool, dry location. Stored that way, expect a one year shelf life.

Questions on Fit

Questions on fit for your bonding process? Call (800) 220-1966 or email [email protected].