Simple Recipes For Making Compatible Repointing Mortar, Historic Masonry
Repair Mortars, Stucco and Plaster using deGruchy's Mortar.

Panel #1

Common Bond in Brickwork

Upper: Modern, stiff mud, wire cut standard 7-5/8
          face brick pointed with mortar struck flat or
          as a flush joint to show aggregates

Mortar Mix: 1 part Mortar G #DGM 200                   (brown/grayish)
                1/4 part washed coal flecks, (or
                 medium grade slag bits).

Lower: Historic, stiff mud, wire cut smooth
          Philadelphia Brick, an 8-1/4 face brick with
          Buttered joint

Mortar Mix: 1 part Mortar F #SCG
                 1/4 part marble dust screenings

Finish Tools- 3/8" slicker, 1/8" slicker, 1/16" slicker
                

Carolina variegated sandstone pointed in a Beveled Ridge joint

Mortar Mix: Mortar G #DGM 50

Finish Tools- 3/8" slicker, 1/2" slicker
                 

Variegated siliceous Iron stone pointed in a Raised and Ruled White Ribbon joint over a neutral colored background mortar brushed flat

Background
Mortar Mix: Mortar G #DGM GRAY

White Ribbon
Mortar Mix: 1 part NHL 3.5
                 2-1/2 parts sharp, well graded and
                     then screened white sand.

Finish Tools- 1/2" slicker, Wire Duster and 1/2" ribbon jointer and a loop

Diopsidic sandstone (Serpentine-like (green) pointed in a Cobweb Ribbon (cobweb also Serpentine-like (curves)!)

Mortar Mix: Mortar G #DGM GRAY

Finish Tools- 1/2" slicker, Wire Duster and 1/2" ribbon jointer and a loop

Limonitic sandstone (yellowish brown) pointed in a Grapevine Stone joint, (not to be confused with the commonly named grapevine joint in brickwork where in that case an incised 1/8 line is impressed into the wet mortar when striking with a grapevine jointer tool.)

Mortar Mix: 1/2 part Mortar G #DGM 100
                1/2 part Mortar G #DGM 250
                 (greenish ochre-brown colored)
                

Finish Tools- 1/2" slicker, 1/2" Stone Grapevine Jointer

Appalachian Bluestone (a sedimentary sandstone) pointed in a **Beveled Ridge joint which had the yellow sand aggregates exposed for a weathered appearance

Mortar Mix: 1 part Mortar G #DGM 100                  (light brown/mud colored)
                1/4-1/2 part sharp, well graded yellow
                concrete sand
(Inclusions of lime chunks were also added along with the sand aggregate to duplicate the imperfection often seen in weathered mortar where the original lime slaking left bits of calcium hydroxide not fully broken down in the putty and where weathering reveals such bits. This denotes a "hot mix was used and fresh slack lime had sand added then used immediately). Mix NHL 3.5 and water, let it harden a week and break it up to add small bits.

Exterior, weathered, (by exposing aggregates) brown coat plaster (AKA stucco, render). Inclusions of lime chunks (see note above) were dashed into the wet plaster

Mortar Mix: 1 part Mortar G #DGM 100                  (light brown/mud-colored)
                 
                 1/4 to 1/2 part brown concrete sand

Tools for Panel 6- 3/8" slicker

Tools for Panel 7- Stucco and Harling trowels, Churn brush and garden hose with water to expose aggregate the next day.

Pennsylvania's Rockhill Granite, (trappe rock), pointed in a **Beveled Ridge joint which had the reddish/brown sand aggregates exposed for a distressed and weathered appearance

Mortar Mix: 1 part Mortar G #DGM 100                  (light brown/mud colored)
                 1/4-1/2 part brown concrete sand                  1/8 part medium grade slag bits

Finish Tools- 1/2" slicker, Churn brush and garden hose with water to expose aggregate the next day.

Philadelphia's Chestnut Hill Stone (Wissahickon Schist), pointed in a **Beveled Ridge joint

Mortar Mix:  1 part Mortar G #DGM 250                   (greenish ochre-brown colored)
                  1/4 part mica fleck inclusions
                   added to simulate the
                   Pennsylvania's Schuylkill River sand
                   which has naturally occurring shist
                   fleck inclusions.

Finish Tools- 1/2" slicker, Churn brush

Note to those in Mt. Airy Region of Philadelphia- The above mix, or substituting DGM 200, is a good match for most Wissahickon Schist repointing work needed on buildings built before 1940.

Note that often in Overhung Ridge pointing of snecked rubble stonework, the head joints can be perfectly perpendicular with the horizontally level bed joints or the head joints are angled from the level bedding plane. From a distance this joint appears to make the semi-squared stones seem more squarely shaped. It also makes the joints look a lot like a ribbon joint, which they are not. Although no painted lime lines or additionally material is added on the surface of the ruled lines, the tightly compressed flat area of the Overhung Ridge joint typically dries lighter than the trailing and ruled edge which is scraped away to bleed into the surrounding texture of stone. This gives the appearance of a painted ribbon joint, but is not to say that in some instances pencylling was not still carried out. In Chestnut Hill, Philadelphia many original Overhung Ridge pointed buildings throughout Germantown Avenue and all the surrounding side streets can still be viewed.

The grapevine joint in stonework is a protruded bead. Easton, PA

This Landenberg, PA farmhouse was repointed and one large brick chimney was completely rebuilt. Color code deGruchy's DGM 50 mortar. Stone joint style is "Brushed Back" using a wire duster tool.

Note- All the photos depicting Color code "DGM 50" is what can be used to replicate this off-white color that we have also called "Standard Cream Color" in the past. Everything required except water and mixing is already in a bag of deGruchy's mortar. However, regular yellow mason's sand that meets ASTM C-144 specifications and NHL 3.5 could be mixed on site to also reproduce this color, or a shade very close to this color at a lesser cost. A mason can use yellow, brown, white or any other sand that meets ASTM C-144 specifications to achieve a similar hue to that of the sand color when using a Natural Hydraulic Lime as the binder.

Log Chinking, Ye Alde Calk, Mend The Gap Between Brick / Stone and Frames