Trimless Letter & Trim Cap Adhesives

Chem-Set TrimLok UV adhesive system for trimless letter and trim cap channel letter bonding

UV Cure Adhesives for Trim Cap Channel Letters & Trimless Letters

The Chem-Set™ TrimLok™ system is a two-product UV and methacrylate lineup for channel letter fabrication. UV3206 LV wicks into tight seams by capillary action and fixtures in 5 to 20 seconds under UV light. UL607 clear structural adhesive builds the rear seam on trimless letters. Together they replace solvent cements, cyanoacrylates, and two-part urethanes on acrylic, polycarbonate, PVC trim cap, and aluminum returns.

Used for trim cap bonding on face-lit and halo-lit channel letters, and for trimless letter assembly on SDS Automation ChannelBender and Trimless LetterForm builds. The cure is optically clear, so the bond line stays invisible behind a lit face.

5 to 20 sec UV cure1,050 to 1,450 psi shearSubstrate failureOptically clearAcrylic, PC, aluminum

+Which Adhesive Do You Need
Chem-Set TrimLok UV3206 LV channel letter UV adhesive in 2 oz, 8 oz, and 1 liter bottles

Flagship

TrimLok UV3206 LV Ultra-Low Viscosity UV Adhesive

2 oz, 8 oz, 1 L  |  SKU: CCA-TLUV3206LV

  • Wicks into tight seams by capillary action, no squeeze-out on the face
  • Cures in 5 to 20 seconds under 365 to 395nm UV light, no clamping
  • Optically clear, 100% solids, no yellowing behind LEDs
  • One-step bond and seal on trim cap channel letters
  • Instant fixture on trimless letters, then reinforce with UL607
UltraLok UL607 clear structural adhesive 50 ml cartridge for trimless channel letter seam reinforcement

Structural Seam

UltraLok UL607 Clear Structural Adhesive

50 ml and 500 ml cartridges, dispense-gun ready

  • Applied along the rear seam of trimless letters
  • 1,050 to 1,450 psi overlap shear, substrate failure on every pair tested
  • Holds strength from -55°F to 250°F
  • Excellent humidity, water, and UV resistance
  • Easy 10:1 mix through a static mixer

Short version: trim cap letters need UV3206 LV only, since it bonds and seals in a single pass. Trimless letters need both, UV3206 LV to fixture the joint in seconds and UL607 to build the structural rear seam. The Trimless Letter Kit bundles both with the dispenser and nozzles.

+Trimless Letter & Trim Cap Bonding Processes

Trimless Letters: Wick + Reinforce

Acrylic faces bonded to aluminum returns on near butt joints and very small bonding areas, including SDS Automation LetterForm and ChannelBender builds.

Trimless channel letter bonding diagram showing UV3206 LV wicked into the acrylic face and aluminum return seam with UL607 reinforcing the rear seam

  • Dry fit the return to the grooved acrylic face, check seam alignment
  • Wick UV3206 LV into the seam with a needle tip, let it fully penetrate
  • Cure per section under UV light to fixture instantly, no clamping
  • Run a UL607 bead along the rear seam for the exterior-grade build

Trim Cap: Weld + Seal in One Step

Polycarbonate or PVC trim cap bonded to acrylic and polycarbonate faces on face-lit and halo-lit channel letters, including small bonding areas.

Trim cap channel letter bonding diagram showing UV3206 LV bonding polycarbonate trim cap to an acrylic letter face

  • UV3206 LV bonds and seals the trim cap to the face in a single pass
  • No second adhesive, no mixing, no dispense gun
  • Wicks into micro-gaps without messy squeeze-out
  • Cures clear, no shadow line behind an illuminated face

+Sizes, Specs & Performance Data

TrimLok UV3206 LV

Property Typical Value
Chemistry One-part UV cure acrylic
Appearance Optically clear, 100% solids
Viscosity 50 to 100 cps
Cure Method UV light, 365 to 395nm (395nm recommended)
Cure Time 5 to 20 seconds per section
Shear Strength Over 1,000 psi on polycarbonate, substrate failure
Substrates Acrylic, polycarbonate, PVC trim cap, aluminum
Packaging 2 oz, 8 oz, and 1 L bottles

Download the UV3206 LV technical data sheet

UltraLok UL607 Clear Structural Adhesive

Property Typical Value
Chemistry Two-part structural methacrylate
Appearance Clear resin, clear activator
Mix Ratio 10:1 by volume
Working Time 6 to 9 minutes
Handling Time 14 to 18 minutes
Full Cure 24 hours. Sets in 2 to 3 hours at 77 F
Hardness 50 to 60 Shore D
Modulus at 1% Strain 81,000 to 86,000 psi
Elongation 5 to 10%
Service Temperature -55 F to 250 F
Substrates Acrylic, polycarbonate, ABS, other plastics, and metals
Application Dispensed through a static mixer
Shelf Life 12 months stored at 40 to 78 F
Packaging 50 ml and 500 ml cartridges

Download the UL607 technical data sheet

UL607 Overlap Shear Strength (ASTM D1002)

Every substrate pair tested failed in the substrate, not the bond line.

Substrates Shear Strength Mode of Failure
ABS to aluminum 1,450 psi Substrate failure
ABS to ABS 1,375 psi Substrate failure
Plexiglass to Plexiglass 1,275 psi Substrate failure
Polycarbonate to polycarbonate 1,150 psi Substrate failure
Polycarbonate to aluminum 1,150 psi Substrate failure
Acrylic to aluminum 1,050 psi Substrate failure

Data from the UL607 technical data sheet. Confirm against the current TDS for your application.

+Which UV Light Do You Need

The light decides your cure speed as much as the adhesive does. Stronger, higher-quality UV output cures more adhesive, faster, over a wider area. A cheaper light means smaller sections and more passes for the same cure. Stay in the 365 to 395nm range, and 395nm is the sweet spot for this adhesive.

Light SKU Level Best For
Handheld UV Flashlight CCH-TLUVLIGHT-HAND Entry Compact paddle light, single LED. Spot work, touch-ups, low-volume runs
Gun-Style UV Light CCH-TLUVLIGHT-GUN Production Pistol grip, tripod-mountable for fixed distance and wide cure radius. Daily letter work
AUV Cool Cure 395nm AUV-FLM1011 Spot Cure Dialed-in 395nm output, direct spot curing. Fastest cure of the three

Shop tip: if cure speed feels slow or inconsistent, check your UV light output and wavelength before you change the adhesive or the process.

+Channel Letter Bonding Kits

Every kit pairs UV3206 LV with the right UV light and safety glasses, so a shop can open the box and start bonding. Kits ladder from a low-volume trial up to full production.

Kit Adhesive Light Best For
Starter Kit 2 oz UV3206 LV 2 oz Handheld flashlight First trial run, proving the process on a set of letters
Starter Kit 8 oz UV3206 LV 8 oz Handheld flashlight Same bundle, more adhesive for steady low-volume work
Mid-Range Kit 8 oz UV3206 LV 8 oz Gun-style light Shops running letters every day
Pro Kit 6x UV3206 LV 8 oz AUV Cool Cure 395 High volume, with a price break on the pro light
Trimless Letter Kit UV3206 LV 2 oz plus UL607 50 ml Handheld flashlight Trimless builds. Adds dispenser and 5 mixing nozzles

All kits include UV safety glasses. The Trimless Letter Kit is the only one with UL607 and the dispensing hardware, since trim cap letters do not need a second adhesive.

+Why Shops Are Switching

Each of the three traditional options gives something up once the letter goes outside and gets lit.

Chemistry Where It Falls Short
Cyanoacrylates Not rated for long-term outdoor exposure. Brittle, no flex for expansion and contraction. Yellows over time, and it shows through a lit face.
Solvent Cements Reformulated blends bond weaker and slower. Will not bond polycarbonate trim cap. Crazes acrylic and cures inconsistently.
Two-Part Urethanes Need dispense guns and mixing nozzles. Slow cure ties up fixtures and slows throughput. Little strength in the thin seams letters actually have.

TrimLok replaces all three. Structural strength on aluminum, polycarbonate, and acrylic. Optically clear, so the bond line stays invisible behind a lit face.

+Channel Letter Adhesive FAQ

What is the best adhesive for bonding trim cap to a channel letter face?

UV3206 LV bonds and seals polycarbonate and PVC trim cap to acrylic and polycarbonate faces in a single pass. It wicks into the seam by capillary action and cures in 5 to 20 seconds under a 365 to 395nm UV light, so there is no clamping and no second adhesive.

Why will solvent cement not bond polycarbonate trim cap?

Solvent cements work by softening and fusing the plastic, and polycarbonate does not respond the way acrylic does. Reformulated blends also bond weaker and slower than older versions, and they can craze acrylic and cure inconsistently. UV3206 LV bonds both substrates without relying on solvent attack.

What adhesive works for trimless channel letters?

Trimless letters use two products. UV3206 LV wicks into the near butt joint between the acrylic face and the aluminum return and fixtures it in seconds. UL607 is then applied along the rear seam. On acrylic to aluminum it tested at 1,050 psi overlap shear with substrate failure, meaning the acrylic gave out before the bond line did.

Does TrimLok work with SDS Automation trimless letters?

Yes. TrimLok is used on trimless letters built on SDS Automation ChannelBender machines with Trimless LetterForm coil, where the acrylic face is grooved around the perimeter and the return seats into the groove. The very small bonding area and near butt joint are exactly what UV3206 LV is formulated to wick into.

What UV wavelength does UV3206 LV need?

Stay in the 365 to 395nm range. 395nm is the sweet spot for this adhesive. Higher-quality UV output cures more adhesive, faster, over a wider area. A weaker light means smaller sections and more passes for the same cure.

Will the bond line show through an illuminated face?

No. UV3206 LV is 100% solids and cures optically clear, so there is no solvent haze, no shrinkage, and no yellowing behind LEDs. That is the difference from cyanoacrylates, which yellow over time and show through a lit face.

How does UL607 mix and dispense?

10:1 by volume through a static mixer. Working time is 6 to 9 minutes, handling time is 14 to 18 minutes, and it fully cures in 24 hours. At 77 F it sets in 2 to 3 hours. Heating to 120 to 140 F for 15 minutes accelerates the cure. Below 55 F the cure slows down.

Can UV3206 LV replace what my shop is running now?

TrimLok is often considered when shops are evaluating solvent cements, cyanoacrylates, or two-part urethanes for channel letter work. Verify performance against your own substrates, seam geometry, and exposure conditions before switching a production process. Our adhesive specialists can help you set up a trial.

+More Lines for Sign Shops
Line What Sign Shops Use It For
High-Bond Tapes VST and VHB acrylic foam tape for panel, trim, and face attachment
Rivet Tape MacTac GS rubber transfer adhesive for sign, plaque, and panel mounting. Instant grab, no cure time
Structural Adhesives Methacrylates and epoxies for metal, composite, and panel bonding
Bonding Fasteners Adhesive-bonded studs and nuts for backs and mounting hardware
Silicone & Caulk One-part adhesives and sealants for weather sealing and general assembly
All UV & Light-Cure The full UV adhesive category beyond the TrimLok system

Questions on your letter build?

Tell us your face material, return material, and seam geometry, and we will point you at the right adhesive and the right UV light. Email technical sales or call 1.800.220.1966. Full system details are in the TrimLok flyer.

Chem-Set TrimLok UV adhesive system for trimless letter and trim cap channel letter bonding

UV Cure Adhesives for Trim Cap Channel Letters & Trimless Letters

The Chem-Set™ TrimLok™ system is a two-product UV and methacrylate lineup for channel letter fabrication. UV3206 LV wicks into tight seams by capillary action and fixtures in 5 to 20 seconds under UV light. UL607 clear structural adhesive builds the rear seam on trimless letters. Together they replace solvent cements, cyanoacrylates, and two-part urethanes on acrylic, polycarbonate, PVC trim cap, and aluminum returns.

Used for trim cap bonding on face-lit and halo-lit channel letters, and for trimless letter assembly on SDS Automation ChannelBender and Trimless LetterForm builds. The cure is optically clear, so the bond line stays invisible behind a lit face.

5 to 20 sec UV cure1,050 to 1,450 psi shearSubstrate failureOptically clearAcrylic, PC, aluminum

+Which Adhesive Do You Need
Chem-Set TrimLok UV3206 LV channel letter UV adhesive in 2 oz, 8 oz, and 1 liter bottles

Flagship

TrimLok UV3206 LV Ultra-Low Viscosity UV Adhesive

2 oz, 8 oz, 1 L  |  SKU: CCA-TLUV3206LV

  • Wicks into tight seams by capillary action, no squeeze-out on the face
  • Cures in 5 to 20 seconds under 365 to 395nm UV light, no clamping
  • Optically clear, 100% solids, no yellowing behind LEDs
  • One-step bond and seal on trim cap channel letters
  • Instant fixture on trimless letters, then reinforce with UL607
UltraLok UL607 clear structural adhesive 50 ml cartridge for trimless channel letter seam reinforcement

Structural Seam

UltraLok UL607 Clear Structural Adhesive

50 ml and 500 ml cartridges, dispense-gun ready

  • Applied along the rear seam of trimless letters
  • 1,050 to 1,450 psi overlap shear, substrate failure on every pair tested
  • Holds strength from -55°F to 250°F
  • Excellent humidity, water, and UV resistance
  • Easy 10:1 mix through a static mixer

Short version: trim cap letters need UV3206 LV only, since it bonds and seals in a single pass. Trimless letters need both, UV3206 LV to fixture the joint in seconds and UL607 to build the structural rear seam. The Trimless Letter Kit bundles both with the dispenser and nozzles.

+Trimless Letter & Trim Cap Bonding Processes

Trimless Letters: Wick + Reinforce

Acrylic faces bonded to aluminum returns on near butt joints and very small bonding areas, including SDS Automation LetterForm and ChannelBender builds.

Trimless channel letter bonding diagram showing UV3206 LV wicked into the acrylic face and aluminum return seam with UL607 reinforcing the rear seam

  • Dry fit the return to the grooved acrylic face, check seam alignment
  • Wick UV3206 LV into the seam with a needle tip, let it fully penetrate
  • Cure per section under UV light to fixture instantly, no clamping
  • Run a UL607 bead along the rear seam for the exterior-grade build

Trim Cap: Weld + Seal in One Step

Polycarbonate or PVC trim cap bonded to acrylic and polycarbonate faces on face-lit and halo-lit channel letters, including small bonding areas.

Trim cap channel letter bonding diagram showing UV3206 LV bonding polycarbonate trim cap to an acrylic letter face

  • UV3206 LV bonds and seals the trim cap to the face in a single pass
  • No second adhesive, no mixing, no dispense gun
  • Wicks into micro-gaps without messy squeeze-out
  • Cures clear, no shadow line behind an illuminated face

+Sizes, Specs & Performance Data

TrimLok UV3206 LV

Property Typical Value
Chemistry One-part UV cure acrylic
Appearance Optically clear, 100% solids
Viscosity 50 to 100 cps
Cure Method UV light, 365 to 395nm (395nm recommended)
Cure Time 5 to 20 seconds per section
Shear Strength Over 1,000 psi on polycarbonate, substrate failure
Substrates Acrylic, polycarbonate, PVC trim cap, aluminum
Packaging 2 oz, 8 oz, and 1 L bottles

Download the UV3206 LV technical data sheet

UltraLok UL607 Clear Structural Adhesive

Property Typical Value
Chemistry Two-part structural methacrylate
Appearance Clear resin, clear activator
Mix Ratio 10:1 by volume
Working Time 6 to 9 minutes
Handling Time 14 to 18 minutes
Full Cure 24 hours. Sets in 2 to 3 hours at 77 F
Hardness 50 to 60 Shore D
Modulus at 1% Strain 81,000 to 86,000 psi
Elongation 5 to 10%
Service Temperature -55 F to 250 F
Substrates Acrylic, polycarbonate, ABS, other plastics, and metals
Application Dispensed through a static mixer
Shelf Life 12 months stored at 40 to 78 F
Packaging 50 ml and 500 ml cartridges

Download the UL607 technical data sheet

UL607 Overlap Shear Strength (ASTM D1002)

Every substrate pair tested failed in the substrate, not the bond line.

Substrates Shear Strength Mode of Failure
ABS to aluminum 1,450 psi Substrate failure
ABS to ABS 1,375 psi Substrate failure
Plexiglass to Plexiglass 1,275 psi Substrate failure
Polycarbonate to polycarbonate 1,150 psi Substrate failure
Polycarbonate to aluminum 1,150 psi Substrate failure
Acrylic to aluminum 1,050 psi Substrate failure

Data from the UL607 technical data sheet. Confirm against the current TDS for your application.

+Which UV Light Do You Need

The light decides your cure speed as much as the adhesive does. Stronger, higher-quality UV output cures more adhesive, faster, over a wider area. A cheaper light means smaller sections and more passes for the same cure. Stay in the 365 to 395nm range, and 395nm is the sweet spot for this adhesive.

Light SKU Level Best For
Handheld UV Flashlight CCH-TLUVLIGHT-HAND Entry Compact paddle light, single LED. Spot work, touch-ups, low-volume runs
Gun-Style UV Light CCH-TLUVLIGHT-GUN Production Pistol grip, tripod-mountable for fixed distance and wide cure radius. Daily letter work
AUV Cool Cure 395nm AUV-FLM1011 Spot Cure Dialed-in 395nm output, direct spot curing. Fastest cure of the three

Shop tip: if cure speed feels slow or inconsistent, check your UV light output and wavelength before you change the adhesive or the process.

+Channel Letter Bonding Kits

Every kit pairs UV3206 LV with the right UV light and safety glasses, so a shop can open the box and start bonding. Kits ladder from a low-volume trial up to full production.

Kit Adhesive Light Best For
Starter Kit 2 oz UV3206 LV 2 oz Handheld flashlight First trial run, proving the process on a set of letters
Starter Kit 8 oz UV3206 LV 8 oz Handheld flashlight Same bundle, more adhesive for steady low-volume work
Mid-Range Kit 8 oz UV3206 LV 8 oz Gun-style light Shops running letters every day
Pro Kit 6x UV3206 LV 8 oz AUV Cool Cure 395 High volume, with a price break on the pro light
Trimless Letter Kit UV3206 LV 2 oz plus UL607 50 ml Handheld flashlight Trimless builds. Adds dispenser and 5 mixing nozzles

All kits include UV safety glasses. The Trimless Letter Kit is the only one with UL607 and the dispensing hardware, since trim cap letters do not need a second adhesive.

+Why Shops Are Switching

Each of the three traditional options gives something up once the letter goes outside and gets lit.

Chemistry Where It Falls Short
Cyanoacrylates Not rated for long-term outdoor exposure. Brittle, no flex for expansion and contraction. Yellows over time, and it shows through a lit face.
Solvent Cements Reformulated blends bond weaker and slower. Will not bond polycarbonate trim cap. Crazes acrylic and cures inconsistently.
Two-Part Urethanes Need dispense guns and mixing nozzles. Slow cure ties up fixtures and slows throughput. Little strength in the thin seams letters actually have.

TrimLok replaces all three. Structural strength on aluminum, polycarbonate, and acrylic. Optically clear, so the bond line stays invisible behind a lit face.

+Channel Letter Adhesive FAQ

What is the best adhesive for bonding trim cap to a channel letter face?

UV3206 LV bonds and seals polycarbonate and PVC trim cap to acrylic and polycarbonate faces in a single pass. It wicks into the seam by capillary action and cures in 5 to 20 seconds under a 365 to 395nm UV light, so there is no clamping and no second adhesive.

Why will solvent cement not bond polycarbonate trim cap?

Solvent cements work by softening and fusing the plastic, and polycarbonate does not respond the way acrylic does. Reformulated blends also bond weaker and slower than older versions, and they can craze acrylic and cure inconsistently. UV3206 LV bonds both substrates without relying on solvent attack.

What adhesive works for trimless channel letters?

Trimless letters use two products. UV3206 LV wicks into the near butt joint between the acrylic face and the aluminum return and fixtures it in seconds. UL607 is then applied along the rear seam. On acrylic to aluminum it tested at 1,050 psi overlap shear with substrate failure, meaning the acrylic gave out before the bond line did.

Does TrimLok work with SDS Automation trimless letters?

Yes. TrimLok is used on trimless letters built on SDS Automation ChannelBender machines with Trimless LetterForm coil, where the acrylic face is grooved around the perimeter and the return seats into the groove. The very small bonding area and near butt joint are exactly what UV3206 LV is formulated to wick into.

What UV wavelength does UV3206 LV need?

Stay in the 365 to 395nm range. 395nm is the sweet spot for this adhesive. Higher-quality UV output cures more adhesive, faster, over a wider area. A weaker light means smaller sections and more passes for the same cure.

Will the bond line show through an illuminated face?

No. UV3206 LV is 100% solids and cures optically clear, so there is no solvent haze, no shrinkage, and no yellowing behind LEDs. That is the difference from cyanoacrylates, which yellow over time and show through a lit face.

How does UL607 mix and dispense?

10:1 by volume through a static mixer. Working time is 6 to 9 minutes, handling time is 14 to 18 minutes, and it fully cures in 24 hours. At 77 F it sets in 2 to 3 hours. Heating to 120 to 140 F for 15 minutes accelerates the cure. Below 55 F the cure slows down.

Can UV3206 LV replace what my shop is running now?

TrimLok is often considered when shops are evaluating solvent cements, cyanoacrylates, or two-part urethanes for channel letter work. Verify performance against your own substrates, seam geometry, and exposure conditions before switching a production process. Our adhesive specialists can help you set up a trial.

+More Lines for Sign Shops
Line What Sign Shops Use It For
High-Bond Tapes VST and VHB acrylic foam tape for panel, trim, and face attachment
Rivet Tape MacTac GS rubber transfer adhesive for sign, plaque, and panel mounting. Instant grab, no cure time
Structural Adhesives Methacrylates and epoxies for metal, composite, and panel bonding
Bonding Fasteners Adhesive-bonded studs and nuts for backs and mounting hardware
Silicone & Caulk One-part adhesives and sealants for weather sealing and general assembly
All UV & Light-Cure The full UV adhesive category beyond the TrimLok system

Questions on your letter build?

Tell us your face material, return material, and seam geometry, and we will point you at the right adhesive and the right UV light. Email technical sales or call 1.800.220.1966. Full system details are in the TrimLok flyer.

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