How To Repair Terracotta Pots

Terracotta is a hard, fired dirt that's reddish-orange in colour, and is commonly used for making pots and garden features. This textile has been used by human civilisations for centuries, dating dorsum to the times of ancient China, Greece and Arab republic of egypt, a testament to its usefulness.

Dissimilar plastic pots which degrade over fourth dimension with exposure to sun'due south UV rays, terracotta pots can terminal for decades, and are a natural textile, making them far more than sustainable to use.

The disadvantage of terracotta is that it is brittle, and tin can cleft if dropped or exposed to freezing temperatures. That shouldn't deter sustainable gardeners though, because terracotta tin can also be repaired, extending its serviceable life considerably.

In this article we'll explicate the various ways that cracked or broken terracotta tin can be repaired.

Can Terracotta Be Glued Back Together?

Well-nigh terracotta pots and garden features can exist repaired fairly easily using modernistic adhesives, as they produce very structurally sound gum joins in this material.

Two dissimilar types of adhesives are be used for repairing terracotta, and each has its advantages and disadvantages.

1. Ii-part epoxy adhesive – products such as Selleys Araldite Super Strength Epoxy (Australia), Loctite Epoxy Agglutinative, J-B WELD Epoxy Agglutinative, 3M Scotch-Weld Epoxy Adhesive (US)
   
2. Landscaping-grade exterior construction adhesive, also known as landscape block adhesive – products such as Selleys Liquid Nails Landscape (Commonwealth of australia), Loctite PL 500 Landscape Block Adhesive (Usa).

So, the question is, which to use?

Two-part Epoxy Adhesive for Terra cotta Repairs

The two-part epoxy adhesives are meliorate for smaller jobs, as it typically comes in a 24mL syringe, or 35mL (2×17.5mL) tubes. It is too amend for croaky items, as it can be forced into a crack more than easily than mural construction agglutinative. For cracked terracotta, utilize epoxy!

When using two-part epoxy, choose the super-force formulations that accept 24 hours to cure, they create a far stronger bond than the faster curing 5-infinitesimal varieties. The longer curing varieties give you lot more working time to glue everything together and align all the pieces together if they're not fitting perfectly. In contrast, with the fast setting epoxy adhesives, in one case you've mixed the glue, there isn't much working time earlier it hardens! It's best to work without having to rush when carrying out these repairs!

Listed below are the features of 2-part epoxy adhesives:

• Dry Clear
• Form a very strong, rigid, durable bond
• Very high h2o resistance, but non for use below the water line
• Can be used for gap filling, the surfaces don't need to fit closely
• Good chemical resistance
• Heat resistant
• Clamping is recommended to reach a stronger bail

Landscape Construction Adhesive for Terracotta Repairs

For larger jobs, exterior mural construction adhesives are a better choice as they comes in large tubes for use in a caulking gun, which hold around 400g. Weight for weight, this adhesive is much cheaper than ii-part epoxy. It's typically used for installation of cement paving stones, securing block walls and capstones, stabilising and strengthening interlocking masonry walls, and for bonding brick, stone, timbers, concrete, metal and wood.

Using a large tube of adhesive for a pocket-size job is not very efficient, though the tubes tin exist capped to exist used at a later time, but they don't continue forever in one case opened.

Additionally, a caulking gun is required to use tubes of construction adhesive, but they're quite inexpensive, just a few dollars, and a expert quality one will last forever.

Listed below are the features of exterior mural construction adhesives:

• High flexibility for coping with seasonal conditions extremes which result in movement.
• Weather resistant bail, only not recommended for permanent water immersion applications.
• High temperature resistance, so the bond won't crack.
• Tin can bridge small-scale gaps when bonding irregular surfaces
• Non corrosive.

I of import disadvantage of outside landscape structure adhesive is that it tin't be painted over.

How to Repair Cracked or Cleaved Terracotta in 5 Easy Steps

In this case, we'll be repairing an unglazed terracotta bird bath pedestal, which is quite large, thick and heavy.

It's important to note that neither two-part epoxy adhesive nor landscape construction adhesive tin be used in applications where the joint will exist nether water permanently or for prolonged periods of fourth dimension, and both are not suitable for use in aquariums or beverage (drinking) h2o systems.

If a bird bath basin for case was cracked, since it holds water and birds drinkable from it, these adhesives would not be suitable. In such applications, aquarium grade silicone sealer would need to be used, it'southward what is used to gum the glass panels of fish tanks together. In such applications, it must be aquarium grade silicone sealant, as the bathroom and roofing grade silicone sealants comprise toxic chemicals added to impale mold, fungi and bacteria.

Step one – Clean and Dry the Surfaces to Be Joined

If the joining surfaces of the broken pieces are dingy, they demand to be cleaned for the adhesive to class a good bond:

How to clean materials beingness glued with two-part epoxy adhesives:

• Clean and dry surfaces to be glued.
• If necessary, wash with water, then allow to dry.

Notation:

If dirt remains on the surfaces to be glued together and can't be removed past washing, scrub them with a soft nylon brush while washing. Don't use a wire brush, as terra cotta is soft, and the wire brush will remove material, destroying the tight fit between parts.

Leave the pieces to dry thoroughly in the sun, it'southward best to wait for as long equally that takes, considering moisture may affect the performance of adhesives.

How to make clean materials being glued with landscape structure adhesives:

• Make clean and ensure surfaces to be glued are sound, dry and free from oil, grease and loose powdery textile.
  
• If necessary, employ mineral turps (turpentine) to clean the surface, then permit to dry.

With either adhesive when repairing cracked terracotta that has not come up apart:

• Make clean the crevice and the surrounding area on the outside and inside surfaces, removing any loose dirt or debris, so it doesn't contaminate the glue bring together and weaken it.

Make clean glue joints ensure that the strongest bond is achieved between pieces.

Step 2 – Pre-fit Parts to Exist Joined and Mark Them for Easy Alignment

Depending on the nature of the repair task, sometimes pieces will obviously fit dorsum together only one way, simply if there are multiple pieces, or if a symmetrical item is broken in two, alignment may not exist then straightforward.

Earlier any glue is applied:

1. Test fit the pieces together.
   
2. Draw an alignment mark using a pencil. A simple line that crosses both pieces volition suffice. Don't printing likewise hard, as you'll want to erase the line afterwards!

If in uncertainty, brand a test marker on the item in a discrete, not-visible location such equally the underside, then endeavour to erase it with a pencil eraser.

A mark drawn with a HB pencil allows quick and precise alignment during gluing.

Step 3 – Set up the Adhesive

Follow the steps outlined below to prepare whichever adhesive will be used.

How to gear up two-part epoxy adhesives:

1. Syringes – snap out cap from plunger and advisedly cut the sealed tips at the finish of the syringe tip.
   Tubes – pierce each tube with spike institute in top of its own cap.
   
2. Manipulate equal parts of both liquids onto a make clean disposable surface. A piece of cardboard works well, or a modest sheet of drinking glass works for a non-disposable option that can be scraped clean and re-used indefinitely.
   
3. Mix both parts together thoroughly.
   
4. Depending on the conception, the instructions on the label may recommend leaving the mixed glue for v-x minutes, and then mixing it again before applying.

   Check the instructions for the product being used, every bit faster drying epoxy glues set faster too, with less working time. The glue used hither is a 24-hour epoxy and the mixed glue remains usable for 1 60 minutes at 20°C.

Two-office epoxy consists of a resin and a hardener in a dual syringe dispenser, or in two separate tubes.

How to prepare exterior landscape construction adhesives:

1. Cut the tip of the cartridge and fit the nozzle
   
2. Cutting the stop of the nozzle to a suitable size opening (approximately 5mm)
   
3. Insert the agglutinative tube into caulking gun.

An inexpensive caulking gun is required for applying the large tubes of construction adhesive

Step 4 – Apply Glue to Broken Edges or Crevice

Gum is applied to the cleaved pieces, which are so fit together using the alignment marks drawn in pencil earlier to line them upward precisely.

With cracks, they can be opened with gentle force per unit area to create a gap to force adhesive in.

When the pieces are fitted together, glue will squeeze out of the join, that is inevitable. Both glues have their specific clean upwardly directions listed below.

Using two-part epoxy adhesives:

1. Utilize mixed mucilage to both surfaces of task, and so bring together.
   
2. Hold join in place using tapes or weights if necessary. Do not apply undue strain to bail for 6-8 hours as this will clasp out to much of the glue and weaken the joint. Maximum force reached afterward 24-72 hours when using a 24 hr epoxy adhesive.
   
3. make clean up whatever backlog gum runoff with a cloth soaked in acetone (or nail polish remover), or carefully scrape off running gum to minimise smearing.

Handy tips for using two-function epoxy adhesives:

• For maximum working fourth dimension, mix in small quantities. Large quantities advance the curing process and reduce working time.
  
• To extend product life replace caps immediately after apply. Ensure you lot wipe backlog from nozzle with a tissue (dipped in acetone or nail smooth remover if necessary) before replacing cap.
  
• When using the tube variant, ensure you replace the correct cap on the correct tube. Placing the wrong cap on the wrong tube will crusade the tube to harden. Caps and tubes are colour coded to help.
  
• To remove product subsequently it has cured (hardened), mechanical action (scraping or sanding) is recommended. Since the product is chemically resistant, solvent volition NOT dissolve this product.
  
• Allow for longer bonding times in colder weather.
  
• Clamping recommended for a stronger bond. Don't use too much force as this will squeeze likewise much gum out, weakening the join.
  
• Bail strength will soften above lxxx°C only strength is retained when temperature returns to normal.
  
• To reposition the bail in one case cured, cheque that the item is rut resistant. If safe, heat the detail slowly, e.yard. in an oven, to at least 150°C. The production volition soften and liquify slightly. Scrape off any excess then reposition the articulation carefully using advisable condom equipment. Allow the particular to cool downward in the right position. The product will reharden once returned to room temperature.

Using landscape structure adhesives:

1. Using the caulking gun, use 'dobs' or 'beads; of adhesive of advisable thickness to ensure sufficient contact and spread between both surfaces. To minimise 'squeeze out' use at to the lowest degree 12mm in from edges.
   
2. Immediately bring surfaces together before product forms a skin (within 5 minutes) and employ sufficient pressure to spread adhesive between both surfaces.
   
3. Practice not wipe excess 'squeeze out'. Expect until production cures and them remove excess by trimming with a sharp blade, but avoid cutting into the bond. Whatsoever adhesive that has dripped onto other surfaces can be cleaned with a cloth soaked with mineral turpentine, merely don't clean the surface of the glue join with it.
   
4. Leave undisturbed until adhesive cures sufficiently. Do not place any load or stress on the join for 24 hours.

Handy tips for using landscape construction adhesives:

• If repositioning materials, fresh adhesive must exist applied to reach bonding.
  
• Working time is 10 minutes. Ensure surfaces are brought together before this time.
  
• Spilt or smeared adhesive is best left to cure and so remove by chafe.

Applying glue to both surfaces to be joined. Here the epoxy agglutinative is being applied to the lesser half of the bird-bath pedestal. Any backlog glue runoff dripping inside is not a problem.

Epoxy adhesive being applied to the summit department of the bird bath pedestal.

Pieces fit together, no clamping was necessary due to the weight of the pieces themselves. Gentle force per unit area was applied to ensure they were seated and both parts were aligned past the pencil mark drawn beyond them. Backlog fresh epoxy glue runoff can be carefully scraped off without smearing information technology besides much, or cleaned with a cloth dipped in acetone (or smash polish remover). Don't scrape off excess construction agglutinative, information technology must be left to dry!

Pace 5 – Clean Up Dry out Glue

Once the gum had dried, any drips and runoff need to be cleaned up and removed , otherwise they can look unsightly.

The bird bath pedestal is left for 24 hours for the glue to attain maximum force. The vertical line across the join on the correct-hand side is the alignment mark fatigued with a pencil. The glue join is darker and there is some glue runoff that needs to exist cleaned upward.

Clean Upward for two-role epoxy adhesives:

• Uncured (unhardened) product may exist removed with acetone.
  
• Cured (hardened) product tin be scraped, and can softened with heat to make scraping easier.
  
• Cured (hardened) product tin be sanded using sandpaper and a sanding block.

Clean Up for landscape construction adhesives:

• Uncured product may be removed with mineral turpentine.
  
• Cured (hardened) production can exist removed by mechanical action such every bit cutting or scraping. Remove excess by trimming with a sharp blade, but avert cutting into the bond.
  
• Cured (hardened) product can be removed with a silicone remover (such equally Selleys Silicone Remover)

In the example below, I used a fibroid 80-dust sandpaper to sand away the dried epoxy adhesive. The material had a rather fibroid finish, so I was able to use a adequately coarse grit sandpaper. For terracotta with a effectively finish, something like a 220-grit may be more appropriate.

Use an aluminium oxide sandpaper, it's are suitable for all materials and is long-lasting, garnet-based sandpapers are only suitable for woodworking.

Sand away remaining mucilage with aluminium oxide sandpaper

The terra cotta dust from sanding shown below tin be gathered, and mixed with epoxy mucilage to fill in any large gaps yet visible in the glue join. Mix epoxy equally described previously, add enough terracotta dust to make a paste, apply to whatever gaps, allow to dry, then sand once again. This step is optional, and I only left the mucilage join as information technology was later on sanding it smooth.

Sanded glue join to remove excess epoxy gum, the bring together line is barely visible.

Here is the repaired birdbath, fix to be set up in the garden.

Fully repaired bird bath pedestal adjacent to its water bowl

The assembled bird bath looks neat, and easily bears the weight of the bowl on top,

The assembled bird bath is almost equally skilful as new!

Birdbath repaired and in identify, exam filled with some h2o, which is why the bowl appears darker, and ready to be filled with h2o.

Birdbath filled with water, to brand sure it balances well, them emptied, it all looks skilful!

Here's a screenshot from a move-sensor trail camera video I use to monitor if any birds are visiting the h2o. A pigeon and silvereye enjoying the bird bath on a hot summertime'southward day!

Cutting Corners…

No matter how much a technical writer lays out instructions on what to utilise and how to perform a certain chore, some people want to cut corners or attempt to practice things on the inexpensive, resulting in disappointment and wasted money.

To explicate the 'whys' with some scientific discipline to dissuade any recklessness, I've included this section.

What Is the Difference Between Interior and Exterior Construction Adhesive?

Mural construction agglutinative is not the same as interior structure adhesive, they are completely unrelated adhesives with completely different backdrop.

Hither are two extracts from the materials rubber information sheets for two such products.

The first is an interior construction adhesive, information technology'southward a polyurethane-based adhesive, and the ingredients are listed for comparison.

SELLEYS LIQUID NAILS RAPID CURE

3. Limerick Information
Chemical ENTITY CAS NO PROPORTION
iv, 4′ – diphenylmethane diisocyanate (MDI) 101-68-8 ten – xxx % (due west/w)
2,iv – diphenylmethane diisocyanate (MDI) 5873-54-one 10 – 30 % (w/w)
Morpholine, 4,4′-(oxydi-2,1-ethanediyl)bis- 6425-39-4 1 – x % (w/w)
Benzene, 1,1′-methylenebis[two-isocyanato- 2536-05-2 <one % (w/due west)
Ingredients adamant to be non-hazardous or below reporting limits Balance
____________
100%

The second is a landscape construction adhesive, for outdoor utilise. It is Not a polyurethane adhesive, and every bit such, the ingredients are completely different.

SELLEYS LIQUID NAILS LANDSCAPE

3. COMPOSITION Information
CHEMICAL ENTITY CAS NO PROPORTION
2-Butanone, O,O',O"-(methylsilylidyne)trioxime 22984-54-nine 1 – 10 % (westward/w)
Distillates, petroleum, hydrotreated middle 64742-46-7 ane – ten % (w/due west)
ii-Butanone, O,O',O"-(ethenylsilylidyne)trioxime 2224-33-1 <one % (west/westward)
1,ii-Ethanediamine, Northward-[3-(trimethoxysilyl)propyl]- 1760-24-iii <1 % (w/w)
Ingredients determined to be non-hazardous or beneath reporting limits Rest
____________
100%

The only similarity is in the proper name of the product, but that's where the similarity ends, they are non interchangeable.

Practice use interior construction adhesive to repair terracotta.

Why Can't Epoxy Adhesives Exist Used in Drink Water Applications?

Two-role epoxy should never be used in applications where drinking water will be in contact with the glue, either for humans, other animals or fish swimming in it. Firstly, the glue will neglect if immersed for prolonged periods of time or permanently underwater, merely the hardened glue is a form of plastic at present banned form utilize in drinking vessels.

Everyone remembers the heath concerns and news headlines that hit worldwide in 2008 over food containers made with BPA plastics and metal drink bottles and cans lined with BPA, and how this chemic leached into food and beverages, poisoning people. Bisphenol A (BPA) and is known endocrine-disruptor, information technology's a synthetic estrogen (xenoestrogen), so information technology mimics the hormone estrogen causes hormonal imbalances. In beast studies, researchers have linked developmental exposure to diverse serious health concerns, such as reproductive harm, increased cancer susceptibility, and abnormalities in encephalon development and fat metabolism.

Now, guess what i one-half of 2-part epoxy resin conttains? Looking at the ingredients list below, it's Bisphenol-A (BPA), so, wear gloves when using it, and don't use it for potable water applications.

SELLEYS ARALDITE SUPER Force EPOXY
Agglutinative – PART A

3. COMPOSITION Data
Chemic ENTITY CAS NO PROPORTION
Bisphenol-A epoxy resin 25068-38-6 >sixty % (west/west)
Bisphenol F epoxy resin 9003-36-5 10-30 % (w/w)
Ingredients adamant to be Non-Hazardous Balance
____________
100%

SELLEYS ARALDITE SUPER Force EPOXY
ADHESIVE – Function B

1,2-Ethanediamine, N,Northward'-bis(2-aminoethyl)- 112-24-3 <10 % (westward/westward)
one,3-Propanediamine, N'-(3-aminopropyl)-North,N-dimethyl- 10563-29-8 <10 % (w/w)
Ingredients determined to be Not-Hazardous Balance
____________
100%

Is Glue Solitary Sufficient to Repair Terracotta?

Nigh terracotta pots and garden features tin be repaired adequately easily using appropriate modern adhesives, which tin can create very structurally sound glue joins in this cloth.

It'southward merely when fastening very large pieces of broken terra cotta that bear very heavy loads that boosted support is required. This is commonly washed by drilling and wiring the pieces together to brace them, and gluing them, simply this is a tedious process and the final result looks unsightly.

To drill and wire terracotta together, a serial of holes are drilled in both pieces of terracotta using a narrow diamond drill (drinking glass and tile drill bit) around 3 – 5mm (one/8" – 3/16") thick. They are used for drilling holes in bathroom tiles and can be purchased from a hardware store.

When using an electric drill, if information technology's a hammer drill, don't utilise the hammer drill setting which is used for drilling masonry such as concrete and brick, only set up it to the regular drilling setting otherwise information technology will smash the terracotta, information technology's a soft material.

For most terracotta items in the garden, glue lonely is sufficient, as long as the correct ane is used for the job.

Source: https://deepgreenpermaculture.com/2021/02/28/how-to-repair-broken-terracotta-pots-and-garden-features/

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