Cemetery Memorial Restoration Procedures

The old style 2-4 inch thick stone that is broken in half at the center as shown here:  (This writing has been rendered largely obsolete by the use of certain approved properly applied epoxy glues, but some principals hold true. For instance if you wish a better repair glue and pin the stone too, but your drill holes should be larger than normal leaving space to include the epoxy around the pin.)
 

As you can see the task here is to put the two parts back together so that they appear to be a part of one stone again. In the process we will need to set the stone upright instead of leaving it in a leaning position and also bond the two broken parts together. It could be said at the outset that the stone broke in half due to the thinness of the stone and because the stone is leaning badly. But the specific cause was probably the result of being struck by a falling tree or limb or perhaps another reason. Stones that are 6 to 12 inches  in thickness of quality Granite rarely break in half unless subject to very violet circumstances, but this stone is only about 3 inches thick and made of a form of limestone which is a softer stone.  Older Stones of the nineteenth century were rarely thicker than four inches. While one could simply straighten the base and place the broken top back on the bottom half that would be a temporary fix and would result in failure with the slightest vibration. The solution will need to be addressed from two approaches.

 The base must be leveled and maybe set in a 40 lb bag of Quickset Concrete or an approved mix of about 1,000 PSI 2 parts white Cement type N, Four parts Hydrated Lime, & 8 Parts Sand all mixed as any other concrete mixed and set below the ground. The procedures provided for the use if Concrete do not hold the endorsement of the Sons of the Confederate Veterans and other historical commissions do not endorse the use of Concrete because of the lack of historical look and other reasons. Also the hardness of concrete when not used below the frost line can crush the stone. They and others tend to say just reset the stone upright and pack the soil around it. Soft Brick braces may be used to help keep the stone upright. At no time should concrete be set above ground and ideally should be used and set at least 12 inches below the ground level to lessen the impact of  the differences in temperatures of the concrete and the original stone composition in the heating and thawing of normal weather patterns.

 The two halves must be cleaned at the fracture seam and bonded with the latest efforts and materials to yield a sustainable upright strength. Here again there is more the train of thought presented.  Some use an Epoxy called **Sikadur 31 (thickest) to the Sikadur 35 (thinnest version) to bond the stone.

But continuing the drilling and pins procedure the tools needed for the above repair are as follows: Carpenter's level, a shovel and a rake, a stiff plastic bristle brush and maybe some other non-acidic of alkaline cleaning supplies, a good quality portable Hand Drill (or use a drill press if one is available) with a drill depth stop set at 2 1/4 inches, a minimum of three 5/16" diameter titanium diamond or concrete drill bits, carpenters measuring tape, and a lead pencil with a sharp point, plastic pail for mixing a 40 lb bag of concrete. Enough water for one or two 40 lb bags of concrete. 
The materials needed are: three tubes of exterior grade epoxy glue, one tube of concrete bonding cement and sealer for filling the fracture, one or two bags of Quickset Concrete,  three 5/16"  by 4" stainless steel or galvanized steel pins. 

To repair the above stone on site one should remove the top half and set it out of the way temporarily. The area around the base is raked clean to get at the base and soil. The soil is pulled back from the base for about a two square foot area or enough to be able to set the base upright and level. This may require digging out as much as the top 4" or more of soil with the shovel. When enough soil is removed to straighten up the base go ahead and stand the base upright & straight taking care not to stress the base joints by applying too much pressure to the straightening effort. If the main stone is loose from the base and moves back and forth you will need to set the main stone into concrete thereby replacing the sloppy base joint. If the base is tight against the stone and it becomes clear that the stone cannot be straightened by a small amount of effort then dig out more soil. Repeat this until the base is loosened enough to be straightened. Now dig out more soil around the base to make a place for the concrete to bond to the base and increase its size and strength. Next using the carpenters level check and adjust the bottom half accordingly to get the stone standing perfectly upright so that it no longer leans toward the ground. Be sure to check the plumb upright from two corners to be certain the stone is upright and not leaning back, to the front or to the side. A bag of quickset concrete is then mixed and poured into the dug out area around the base to anchor the base and the bottom half of the stone. When finished the soil is raked back into place to cover the base of the stone as it was before. Wait thirty minutes until the concrete is set enough to proceed without loosening the stone. Of course one may need to modify the instruction above for a stone that was set shallow in the ground. In such a situation set the stone base deeper into the ground than it was before.  At the opposite spectrum when the stone is set abnormally deep into the ground it may need to be dug up and set in place with less depth. However, modify your procedures above as needed according to the depth of the stone. If you remove the stone be sure you line it up in the same place it was before. Never move a stone without an original drawing of its exact place in the cemetery even if that is not the place where the stone was originally set. It would be a disaster to historians and laws may be broken to place Joe Blow's stone next to John Doe's in error. Old cemeteries rarely have perfect rows for the graves and memorials. Clustering families in group burials was more important to our ancestors than perfect order.

Now that we have the base half well anchored in concrete in the ground and standing upright we must turn our attention to bonding the upper half to the bottom half at the fracture line. First give the two halves a quick inspection looking for superficial cracks. If these are found then special attention will be required for that. For the sake of this discussion we have found the two halves to be sound and ready to proceed. To work with the stone you will need to clean the fractured surface of both the bottom and top half. Take the brush and scrub the fractured face of both pieces until they are both free of debris and clean enough to set tightly together and support the glues. Use other cleaning supplies if needed but use no harsh acid or alkaline cleaning compounds. 

Next we will measure and drill three holes into the face of the fracture of the base half and three matching holes are drilled into the upper half of the face of the fracture. The drawing below depicts that process. Afterward the pins are set in place in Epoxy Glue to support the two halves. These three holes in each half will be 1/4 inches deeper than the length of the pins in this case 2 inches into each stone half. Therefore the hole depth must be 2 1/4 inches.
The holes must match up or the two fracture lines of the stone will not set together properly.  The pins will be bonded into the stone halves with Epoxy glue to insure a long term outcome. If there is loose slop or the pin depth is not enough the upper half of the stone will fall or a large crack will show between the two halves leaving room for future failure.  I must add here that accurately drilling six 2 1/4 inch depth holes with 5/16 bit in hard stone is no easy feat. A drill press works much better than a hand drill for this process because the process can be stabilized and set up as a fixture. If it requires a drill press one would remove the stone from the cemetery. In that case first put into place a temporary marker with the vital stone inscription. Afterward one could proceed to the site where the drill press is set up. Also before removing the stone from the cemetery one will need to notify the proper cemetery authorities so that permission may be granted and an accounting for the whereabouts of the stone is available at all times.

Proceeding as if we are repairing on site the first task in drilling the holes is to measure and mark the place to drill the three pin holes in the upper half and lower half.. The two outside pins will be placed two inches from the outside edge. The other pin will be placed in the center of the fracture. So take a carpenters measuring tape and measure two inches from the edge of the top and bottom for both the top half and the lower half. Next take the tape and measure across the thickness of the stone to get the center of the hole. Mark with the lead pencil the point that is in the center of the stone fracture but two inches from the edge. For the center holes measure the width of the stone and mark that point and then center that point by finding 1/2 of the thickness of the stone. Now measure the last outside pin hole 2" from that edge and center and mark the point. Do that on the upper stone half and the lower half. These pin holes must match up and be the right depth or the top of the stone will not set on the fracture properly to close up the gap. If one is unsure of the markings a good way to check that is to break apart an old black or blue ball point pin and touch the gooey inked end to the marked points of the upper half. Then carefully set the upper half down straight on the lower half. This should cause the ink from the upper half to mark the same point on the lower half as your previous marks there. Be careful with this. If you use too much ink or you do not set the stone parts together correctly you will smear the ink over the original marked holes instead of confirming your markings.

Next drill the holes making certain the drill is held steady and in a manner that will cause the holes to be straight up and down. If you can find a jig fixture for this in a hardware store this will be easier. Drilling the holes is probably the most critical task. One error here and the effort will be lost. First set the drill stop to 2 1/4 inches to get the right depth. After the holes are drilled and the scrapes are cleaned away it is time to test our fit. Take the pins and set them into the pinholes into the lower half of the stone. Next take the upper half of the stone and set that down onto the pins in place much like the drawing above. The two parts should come together tightly and without sloppiness. If they don't then you may need to later apply more epoxy if there is too much slack in the sides of the pin holes. If the hole depth is not proper the two parts will come together leaving a gap. In that case go back and drill the holes to the proper depth. If the stone comes together but is off center and the fracture does not match then you must correct that by making  the holes larger in the bottom half. You might consider using a size larger drill bit to correct that. Now that we have the two halves fitting together remove the pins and apply the Epoxy glue to the pin holes in the lower half using about 1/2 tube of glue in each hole. As quickly as possible set the pins into the holes on the bottom half making certain they are set 2 inches into the pinholes and not 2 1/4. 

Last we will need to apply the bonding cement over the surface of both the upper fracture and the lower fracture to seal out the water from the break. This must be done quickly so that the epoxy for the pins is not past its hardening prime. Next fill the three upper pin holes with epoxy and set the upper part of the stone on the lower half. Work it down on the lower section making certain the excess glue is wiped up and does not bleed down on the inscription or face of the stone. 

And viola we have the result shown at left. Well not quite. The image shown at left is actually a computer graphic stone restoration of Elizabeth (Fine) Coffee, 1809-1882, wife of Calvin Coffee. Gilbreath-Morrow Cemetery. The original stone still stands broken in the cemetery as shown in the first picture above. If you look closely you can see the imperfections of the computer graphic restoration detail. I have not tackled the actual repair of this stone because there are so many of these broken stones that this is just one of many on my list of future repairs I hope to tackle.

 

 

 

 

 

**Suitable commercial substitutes for Epoxies are "Bons One Duropoxi Epoxy" Part A & Part B. Mixed at 50/50. Tenax DOMA 10 Part  A & B  Epoxy.