Sunday, October 2, 2011

Masking Tape "Band-aid" Tutorial

I've been experimenting with using masking tape to "splint" small or delicate metal clay pieces that have had accidents for repair. Pictures are with dry, pre-fired clay, but I have also used this method to join pieces that broke after firing.

I apologize for some of the slightly blurred photos, but I would appreciate any and all feedback on this!

Step 1: Assess Damage

This break is kind of cool looking to me, but not what I was going for. Is this fixable or is it better to start over? Are there clean breaks? yes. Got all the pieces? yes. Are there other delicate areas to be aware of during repair? yes, the other spokes. Ready to play doctor? Yes? see step 2.

Step 2: Tape offending piece (tape is sticky side up like fly paper)
For a piece with multiple breaks, join the smallest pieces with water and paste to form a larger unit that is easier to handle when dry.

Step 3: Position pieces
Use the tape to pick up and align the pieces. Like a bandage on a cut, orient the tape so it overlaps more than just the area of the join.

Step 4: "Tacking" the join with paste

The tape will let you open up the join to apply paste, and holds them in correct alignment while the paste is wet. I have put taped pieces on a griddle set to 200F degrees to dry with no ill effects. The adhesive on the tape seems to soften a little, but it leaves no residue if allowed to cool before removing the tape.

Update:  On fired pieces I use oil paste for low profile join. For joins that gape a bit, Overlay paste (dries hard & quickly, can be torch fired) and lump clay.

Step 5: Reinforce join with syringe or lump clay
 With the tape supporting the repaired side, piece can be handled safely from the other side.

Step 6: Remove tape
 Excess paste that does not stick to the tape can be removed with brush or file.

Depending on the repair (ex. filigree) have left the tape on to be fired off. Sometimes the join needs to be fired for stability before being reinforced with additional clay.

Step 7: Face lift!
 Check the front of the piece to see if repaired areas need refinement from the front.

Finished cogwheel spinners!