Improved Cleat Installation Method Over the years I have experimented with several techniques for installing internal cleats through the f-hole, always looking for a method that is both reliable and easy to control. This revised approach makes positioning the cleat much more predictable by using temporary magnets, an exterior mold, and a small amount of CA glue to hold the clamp in exactly the right orientation before the permanent woodworking glue is applied. The result is a cleaner installation with better control over the cleat's placement while minimizing the frustration of working inside the instrument through such a limited opening. - Glue the cracks: Glue the two cracks and allow them to align securely before installing the cleat.
- Make the cleat: Prepare the cleat to the correct size and shape for the repair.
- Make an exterior mold: Create an outside mold that matches the arch of the top so the repaired area is properly supported during clamping.
- Secure the mold: Tape the exterior mold onto the top so it does not move while the cleat is being installed.
- Mark the clamp angle: Draw a line on the cleat to show the angle where the clamp will need to attach.
- Drill the cleat: Drill a small hole through the cleat so it can be held and guided into position.
- Add temporary tape: Use double-sided tape, or a folded piece of tape, and attach it to the center of the cleat.
- Secure the magnet: Add a very small drop of glue to help hold the tape to the damp cleat and the magnet to the tape.
- Guide the cleat with wire: Use a wire to hold the cleat while slipping it through the f-hole.
- Attach the interior magnet: Place a small magnet onto the taped area of the cleat and allow it to dry.
- Capture the magnet: Use an exterior magnet to capture the magnetic field of the interior magnet and control the cleat from outside the instrument.
- Remove the wire: Once the cleat is controlled by the magnets, remove the guide wire.
- Adjust the cleat angle: Move the cleat with the exterior magnet until the angle is correct.
- Prepare the clamp: Put a small amount of CA glue onto the clamp and slip it into the violin.
- Attach the clamp to the cleat: Push the clamp against the cleat, then lightly tighten it so the CA glue can dry and hold the clamp in the correct position.
- Remove the exterior magnet: Once the clamp is attached, remove the outside magnet.
- Remove the interior magnet and tape: Take away the interior magnet and temporary tape before the final gluing step.
- Check the placement: Confirm that the cleat will end up in the correct position before applying the permanent glue.
- Apply woodworking glue: Use a Q-tip to spread woodworking glue onto the cleat.
- Clamp the cleat: Move the cleat into place and clamp it firmly against the exterior mold.
- Allow to cure: Wait 24 hours for the glue to dry fully.
- Release the clamp: After the glue has cured, gently wiggle the clamp until the CA glue bond releases.
- Complete the repair: The cleat is now installed inside the violin without removing the top.
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First Repair Method:This violin came in with a crack along the right side of the top. Fortunately, the crack lined up well, so it could be glued without opening the seam. After bringing it back together and stabilizing the area with an outside mold, the next step was to reinforce it with a larger cleat installed through the f-hole. That part takes a bit more care, using a combination of magnets, a clamp, and some careful positioning to get everything aligned properly. The goal was to secure the crack solidly while keeping the repair as clean and unobtrusive as possible. Violin Top Crack Repair with Internal Cleat (Through f-hole)- Assess the crack: The crack on the right side aligned well, so there was no need to open the seam.
- Glue the crack: Bring the crack together and glue it, ensuring proper alignment.
- Stabilize with an outside mold: The next day, reglue the upper portion of the crack using an outside mold for support.
- Prepare a large cleat: Make a larger cleat for reinforcement and soak it in water so it can conform slightly to the surface.
- Pre-shape the cleat: Allow the cleat to warp slightly so it bulges in the center, helping it seat properly when clamped.
- Mark the alignment: Draw a line on the cleat to reference the angle of the clamp for accurate positioning.
- Set a reference line: Tape the outside mold to the top and add a piece of tape with a line marking the crack position so alignment can be quickly checked during setup.
- Set up the tools: Use a sharp, thin knife to handle and position the cleat, and a bent wire with a magnet to hold the cleat in alignment with the clamp foot.
- Practice the placement: Do a dry run to work out the alignment and positioning before applying glue.
- Position the clamp: Insert the clamp through the f-hole and place a small drop of CA glue on the clamp foot.
- Guide the cleat into place: Fish the cleat in through the f-hole, using the knife to guide it into alignment.
- Engage the magnet: Place a magnet on the outside to hold the cleat against the clamp foot.
- Remove the knife: Once the cleat is held in position, carefully withdraw the knife.
- Release the magnet: After the CA glue sets, remove the magnet so the cleat remains in place on the foot.
- Glue and clamp the cleat: If alignment is correct, apply glue to the cleat and clamp it against the outside mold.
- Remove the clamp: The next day, gently wiggle the clamp free from the cleat.
- Seal the crack: Apply a small amount of clear varnish to protect the crack from dirt and moisture.
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This is the method I use when installing a larger cleat through a violin f-hole. Each individual piece can fit through the opening, but once assembled, the cleat would be too large to pass through as a single unit. On a cello, I would normally install a larger cleat as one piece, but that simply isn’t possible through a violin f-hole. By staging the cleat and clamp separately and aligning everything during a dry run, it’s possible to get a solid reinforcement in place while still working within the limits of the instrument. |
