Materials: Leather Soft Fill (LSF), Sub-patch Material (HAP), Leather Bond Adhesive (LA-1), Velour Fast Dry Adhesive (63), Leather Cream Fill (LCF), Deep Fill (DF11), Heavy Duty Repair Compound (HD), Leather Vinyl Repair Compound (LRC), Sub-patch Adhesive (HH66), Spatula (GR870), Tweezers (TW6) , Chill Bar (CB), Triclean (TC).
NOTE: If the damage is stitch-related, for example a loosened stitch, skip these repair techniques and consult the section “Blind Stitch Sewing Methods”.
Step 1: PREP CLEANING
A. Use Triclean (TC) w/ nylon brush or a scotch brite pad.
The prep cleaning of the Leather is a vital & essential part of the whole repair process. This not only improves the look of the finished repair but also ensures maximum adhesion.
First, clean thoroughly with Triclean prep cleaner (TC) to remove all dirt, wax and silicone contamination. Spray a wet coat of triclean then use a nylon brush or a scotch brite pad to scrub completely, take extra time on the stitching and leather creases. Repeat for optimum results.
Some leathers have a protective coating. Use 600-grit sand paper with Triclean (TC) to wet sand. This helps to break the surface tension of the protective coating which can cause peeling if not removed. Apply Triclean (TC) again and wipe clean with a clean lint free towel or a paper towel.
Step 2: SUB-PATCH (when needed)
A. Select sub-patch material: Sub-patch material (HAP) or Fine mesh (FM) .
B. Select sub-patch glue: Sub-patch adhesive (HH66) , Leather Bond Adhesive (LA-1), Velour adhesive (63)
When a hole penetrates the leather all the way through to the foam insert a sub-patch. Use Sub-patch Material (HAP) or a piece of Fine Mesh (FM) (apply masking tape to one side of the fine mesh for reinforcement and to keep adhesive from adhering to the foam).
Cut the sub-patch slightly greater (at least ¼") than the diameter or length of the hole, in order to adhere to the edges of the repair area. Insert it between the foam and the leather with a palette knife or tweezers. Replace any missing foam to level out the repair area. Adhere the sub-patch with Leather Bond Adhesive (LA-1), Velour adhesive (63) or Sub-patch adhesive (HH66). Dry completely to ensure maximum sub-patch adhesion before the repair process. A hair dryer or low temperature heat gun can speed the drying process. Be careful inserting sub-patch so as not to cause a bump in the repaired area.
Step 3: REPAIR
Select method:
1) Heat cure repair (requiring a heat gun or a mini-iron for curing).
2) Air-dry repair (low heat repair)
Although it is much quicker to work with heat-curing products, most leather surfaces are thin, which requires constant temperature control of the surface (to much heat will shrink and wrinkle the leather). Use heat-cure repairs on thick leather surfaces structural damage where strength is needed, or when the hole has completely penetrated the leather.
In all other cases (scratches, topcoat damage, creases, etc), repair by using products that do not require heat. Remember, use air dryer to speed up the drying/curing. Be careful not to overheat the surface.
TIP: To control the temperature of the leather, place your hand near the repair. If your hand can not take the heat, neither can the leather.
AIR DRY REPAIR - LEATHER
REPAIRING SCRATCHES AND NICKS (LCF, LSF, SFF)
Several filling products can be used for this process, each offering different filling capacities.
1) Always sand scratches or nicks first. Wet sand with Triclean (TC) using 600# or 320# sandpaper. After sanding, check to see if any filling is needed.
REPAIRING SMALL-TO-MEDIUM DAMAGES (LSF, DF-11 or LFF)
Fill the damaged area with a coat of Leather Soft Fill (LSF), this air dry medium filler sands easily. Use only 600# sandpaper.
Use a pallette knife when applying all products. Apply in thin layers, allowing for drying between coats.
A lightly moistened paper towel may help to spread the all products before they have thoroughly dried. Instead of sanding filler, lightly use Triclean (TC) to feather out the edges.
REPAIRING LARGE DAMAGES (LFF, DF-11)
Fill the damaged area with a coat of Deep Fill (DF-11) (can not sand) or Leather Fix Fill (LFF) (can be sanded with 220# sandpaper after drying). These air dry water base fillers are used for deeper scratches.
1) First apply a thin coat of Leather Bond Adhesive (LA-1) inside the repair area. Allow to dry.
2) Apply the leather filler in thin layers, allow to dry between coats or use a hair dryer to speed drying. Make sure to spread well over the edges of the damage when applying. Use a palette knife when applying all products. A lightly moistened lint free paper towel may help to spread the filler.
3) Topcoat with a thin layer of Leather Cream Fill (LCF). Dry completely.
REPAIRING SURFACE CRACKS
Since most surface cracks are the original color coat that is cracking and not the leather itself. Following these four steps can eliminate a majority of the existing cracks.
Step 1: Apply Triclean prep cleaner (TC) to the cracked surface, wet sand with 220 to 600-grit sandpaper (severely damaged surfaces may require 100-grit sandpaper). Apply more triclean as needed. Sand down to bare leather if needed.
Step 2: Wipe Triclean prep cleaner (TC) over the entire sanded area with a clean moist cloth or lint free paper towel to remove excess residue.
Allow the surface to dry before proceeding. Drying time may be accelerated with a hair dryer.
Step 3: For cracks in the leather, apply a leather crack fill (LSF or DF-11) with a palette knife. Air dry (use a hair dryer to speed drying) and then softly sand the surface to smooth the edges or use triclean with a palette knife to smooth edges.
(For large cracks, use the “Repairing Scratches and Digs” process explained above.)
Step 4: Cover the surface with one or several coats of Leather Cream Fill (LCF). This puts a final smooth skin coat on the surface to match the look and feel of the repair with the surrounding surface. Apply with a palette knife or just wipe on with a paper towel. Apply several very thin layers over the repair on the surface. Let air dry, or use a hair dryer to speed drying.
HEAT CURE REPAIR - LEATHER
1) Heat Cure Process: same as vinyl repair
NOTE: Leather repair compounds start curing at 350 degrees with a maximum temperature of 450 degrees. How much heat the leather can with-stand will determine the heat gun setting.
a) Glue in sub-patch material if needed.
b) Fill repair with Heavy Duty Repair Compound (HD) using palette knife.
c) Heat compound until it turns clear. Keep heat gun moving in a slow circular motion. Immediately press with chill bar to produce a flat repair and to pull the heat out of the repair so more compound can be applied. Re-heat repair and press with grain pad or grain paper.
d) When using a mini iron, Lay the Teflon Mat (TM) over the area and cure the compound by ironing it with medium pressure back and forth until the compound is cured. (Curing time depends on the thickness of the compound.
IMPORTANT: Before removing the “Teflon Mat,” apply the aluminum Chill Bar (CB) to the Teflon mat to cool the repair and keep the Mat from sticking.
Step 4: Sealing
Spray Flex Primer (95FA) or Aerosol Flex Primer (AFP) over the repair to seal and improve the surface for adhesion of the color. Aerosol Spray Grain (ASG) can also be use to seal the repair with a pebble grain effect.
Step 5: Texture
This process may not be required if a heat-cure repair was performed (Graining Pads can be used for the texture). However, when required, the following options can complete or improve the texture of the repair.
OPTION 1: For medium texture, spray the repaired piece with Water Base Spray Grain (S-3) or Aerosol Spray Grain (ASG) (water-base). For a smooth grain texture, spray with Water Base Spray-on-Grain (W-2). Use a Preval Sprayer for S-3 and W-2. The distance that the spray grain applied, determines the size of the pebble grain. This is option is very useful in the case of problem problems with matching the new texture to the original. To apply, simply spray the new texture over a wide area in and around the repair, even texturizing the entire piece if desired.
OPTION 2: Apply a coat of Leather Gel (LG) . After allowing 30-60 seconds of drying, wet a grain pad with water and press the graining pad onto the repair area and hold. Remove the pad and check grain. Re-apply the graining pad as long as the product has not dried. Or you can repeat the whole process if desired.
Step 6: Color
To color the piece, consult the Applying Color section of the training manual.