22 September 2021 at 10:28 pm #729824
The attached photos are from ornamentation in a US house built in the late 1800s. I’m helping someone who is restoring after some water damage. The two attached photos show ornamentation associated with door casing. They look to me like a casting, perhaps of clay, stuck onto an oak substrate. There are two elements, the scroll / capital, and below it, an acanthus leaf (?). Does anyone know how these were made and how to reproduce them?23 September 2021 at 9:39 pm #729919Sven-Olof JanssonParticipant
For whatever it’s worth:
The change in dimension of the ornamentation appears to differ from the wood behind. My guess – and it’s really a guess – is that the ornamentations are made out of papier maché. This property of deviating from surrounding wood upon changes in humidity, is apparently used as a means to identify the material.
The attached link directs to a paper that gives some insights on how it is used.
Never seen stucco applied to wood, but perhaps…
London, UK; Boston, MA23 September 2021 at 10:03 pm #729923deanbeckerParticipant
Most likely plaster or a mortar . Dont you think. I have found references on the net for large moulding slip moulds that were used with plaster or some such that made the designs . Mostly they were from eastern europe. I think. I don’t know the language in them.23 September 2021 at 10:33 pm #729924
I should give a scale for those photos: Width is about 3″ (7.5 cm).23 September 2021 at 11:32 pm #729928
Our shop used to use precast “plants “ that were cast in rubber mold with wood flour and hide glue.
Before that, they were made with wood flour and linseed oil which was baked in an autoclave. A similar process was made to produce linoleum.
Nowadays CNC reproduction has gained part of the market, as has urethane casting.
Many plants can still be bought through millword suppliers.
One such place is Van Dykes restorers.
Here’s a Capital on the same theme as the one you showed. There are probably other sizes and styles available.
Yours looks like two plants, the ionic capital and the surface decoration under it. The piece over the capital might be a third casting.
Sometimes you can approximate an existing piece by literally cutting and pasting existing purchased pieces..23 September 2021 at 11:44 pm #729934
Here is a urethane casting closer to what you show. There are dozens out there.
Just google Applied molding ionic capital.
Somebody with even modest painting skills can make that look like wood.23 September 2021 at 11:51 pm #729937
Larry, how did you make the wood flour? I find it challenging to make large amounts of sawdust when I need to make a filler and am not sure how I’d make enough fine flour to cast something like this. We want to exactly match what is there. We’re thinking of casting a negative mold from the ornaments that exist, then casting positives from the mold. Plaster seemed like it would be too brittle, but glue and wood flour sounds plausible. It would need to be exceptionally fine and uniform flour, though.23 September 2021 at 11:53 pm #729938
Sven-Olof- Very interesting. I never would have dreamed of papier maché!24 September 2021 at 3:11 am #729949
You don’t make it unless you have a lot of time on your hands, you buy it. I have a tub of it from the last kayak I built.
The principle use I’m aware of nowadays it to mix with epoxy to thicken it for applications in boatbuilding like stitch and glue construction.
Most marine supply places or places that sell epoxy will have it.
It easier to make silicone molds and cast in foam urethane. More durable and quicker, but the old fashioned wood flour and hot hide glue works. Either way, you will have to do some staining or painting. Urethane can simulate wood pretty well if you prime with a flat grey spray auto primer and then brush stain it with dye stain and overcoat with an acrylic stain like General Finishes. Practice on any primed surface.
Edit. Use a couple drops of detergent to get the flour to absorb water.
Add Silica to make it flow better. ( available from the same sources)24 September 2021 at 5:12 am #729960
One other possibility is to use Durham’s water putty , though I see that product as the quick amd dirty solution amd not long term.
It’s plaster based with adhesion for adhesion, flow, and stiffness.
It sticks well to wood and gets stiff in less than an hour.
You just add water.24 September 2021 at 8:21 pm #730062
Thank’s Larry. I like to use Durham’s on the table of my miter box. When the kerfs get bigger than I like, I fill them with Durham’s.26 September 2021 at 5:28 pm #730249EdmundParticipant
Hey Ed!, long time!
There’s obv several ways to produce them, but the cracking makes me think one of the methods mentioned above might have been employed. It’s possible the originals were hand–carved and the pictures show replacements applied later, but without the provenance of the house there’s no way to be sure.
To produce them today, the easiest thing probably is, as mentioned above, to just buy them.
Next easiest depends if you have a CNC or not. You could then either have it make the mold for mass production via the methods mentioned above or have the CNC make them directly out of your preferred material.
If no CNC, you could buy some casting resin and other mold-making supplies and make your own mold. This would be inexpensive, but given the cracks, would take some touch-up work after the fact, and if you’ve never done that kind of work, might take a few tries to get an acceptable result. This obv depends on being able to remove one of the pieces intact, which is not a sure thing.
Most challenging, but imo the most rewarding would be to learn to carve them yourself. Again, the pictures you showed suggest to me that it’s an applique, so perhaps that will make carving them slightly less challenging.28 September 2021 at 9:53 am #730433Benoît Van NotenParticipant
People sanding wooden floor would produce large quantities of fine sawdust. You might try to find one.
Or if you are restoring a house, you might have to do it in this house.28 September 2021 at 3:07 pm #730447
@ETMO It has been a long time! In this particular case, an exact reproduction is desired, so off the shelf is unlikely. I suspect the originals were castings. That approach appeals to me, although I’m not the one who is going to do the work. I’m just helping research ideas. I agree that years have removed the crispness. I think the original could be carefully cleaned, a cast taken, and then a plaster positive could be made. The plaster could be refined with dental tools, bondo, durham’s, and pixie dust…whatever it takes to build up what is missing and sharpen what is dull. Now, take another negative and work from that.
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