Repairing Loose Cast Iron Joints

Procedure code:
572502S
Source:
Outdoor Sculpture Manual - Cpb
Division:
Metals
Section:
Ornamental Metal Castings
Last Modified:
06/16/2015

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We’ve reviewed these procedures for general consistency with federal standards for rehabilitating historic buildings and provide them only as a reference. Specifications should only be applied under the guidance of a qualified preservation professional who can assess the applicability of a procedure to a particular building, project or location. References to products and suppliers serve as general guidelines and do not constitute a federal endorsement nor a determination that a product or method is the best alternative or compliant with current environmental regulations and safety standards.


Part 1—General

1.01 Summary

A. This procedure provides guidance on inspecting, tightening and repairing connections of cast iron features that have become loose or are deteriorated.

Note: This procedure should be performed on an as-needed basis based on the results of semi-annual inspections.

Part 2—Products

2.01 Materials

A. Nuts and bolts of appropriate sizes to match existing or as required. Use AISI 316 stainless steel or bronze connectors where possible.

B. Mineral spirits, naval jelly, etc. as required for removing deteriorated paint and corrosion. For guidance on paint removal from wrought iron, cast iron and steel, see 05010-05-R, 05010-16-R and 05010-17-R.

C. Sandpaper and/or steel wool as required to remove corrosion.

D. Molten lead

E. New cast or wrought iron, etc. for welded repairs.

F. High quality, paintable caulk

2.02 Equipment

A. Wrenches, pliers, screwdrivers

B. Welding equipment

C. Stiff bristle brush

PART 3—Execution

3.01 Erection, Installation, Application

A. Simple loose connections:

  1. Locate loose joints and bolts, nuts and screws, etc.
  2. Carefully remove loose connectors and clean them of all corrosion and loose debris using sandpaper, steel wool, or a stiff bristle brush. Clean holes and surfaces of feature as well.
  3. Reinstall connectors in original location and tighten connections which are functional.

B. Deteriorated connections requiring replacement screws/bolts:

  1. Remove connectors which are severely deteriorated and frozen, for replacement with new.
  2. Determine the number and size of required new connectors.
  3. Clean holes and surfaces of feature of all rust and loose debris.
  4. If hole has corroded, redrill as required to standard bolt or screw size.
  5. Insert new stainless steel or bronze connector as required to secure connection.

C. Wobbly newel posts or similar features:

  1. If entire assembly is wobbly, carefully dismantle feature. Mark pieces as required in inconspicuous spot for easy reassembly.
  2. Inspect center threaded rod or anchor pin(s) and remove from setting hole in base.
  3. Clean base of rod or pin of all corrosion and loose paint. Blow-out hole with air blast to clean out debris.
  4. Repaint base of rod or pin as required before placing it back into setting hole and packing hole with molten lead.
  5. Backprime all pieces of feature and reassemble.
  6. If required to restore and/or improve stability of newel, weld small wrought or cast iron tabs at base of newel (two tabs per face).
  7. Thread small stainless steel or bronze screws or bolts through tabs into masonry base and fill holes with molten lead.

D. Seal all seams with high quality, paintable caulk. Note: Do not use concrete to fill any voids. Do not seal weep holes or drainage holes.

E. Paint feature as required. For guidance on painting cast iron, see 05010-13-S and 09900-07-S.

Last Reviewed: 2017-08-13