Terra cotta

I now have my kiln back in my home studio after removing it from the gallery basement which seemed like the ideal place for it at the time I bought it. So it’s set up now at home where it’s much more convienient to monitor.

I fired a couple of older raw clay original models with complete success, including the Astor Place subway beaver model which was just 1/4″ less tall than the inside of the kiln with the lid closed.

I’m considering “converting” the Art Deco D5 model into a terracotta line, here’s the original clay model that I fired in the kiln a year ago after making the rubber mold for casting it in interior cast-stone and concrete:

 

In order to “convert” it to enable making them in fired pressed clay, I would have to make a positive cast in rubber and then make a 5 piece plaster mold of that positive rubber cast. The idea of the rubber positive is the rubber is soft and “gives” so that pulling a hard plaster shell mold off it, undercuts slide right out easily.

Once I have the positive rubber I can make molds from that as needed, making one to start with. When the plaster mold is dry then the clay can be hand-pressed into it, allowed to stiffen slightly, removed, dried completely and then fired in the kiln.

One thing with the “converting” is that  in the processes there is about a 5% shrinkage of the clay from wet to dry and another 5% shrinkgage during firing for a total of about 10% or 1″ loss per 10″ which on this panel will result in it being about 2″ less wide and maybe 1-1/4″ less tall.

I think this fall/winter I’m going to do this.

Actually, I decided to go ahead and order the $200 worth of mold rubber I need to make the replacement mold for this since the original mold rubber by Quantum Silicones that I used in 2007 to make the first mold turned out to be total  garbage. Hopefully this weekend if the rubber arrives before Friday I will have the master cast all set up and ready to mold Saturday.

I should have enough left over from the two gallons added to the left-over rubber I have on hand to make the positive mold too- on Sunday if all goes well.

At least with this I can get the process started, I don’t have any molding plaster on-hand to make the press-mold with though, and the regular cast stone is not suitable for this as it hardens up extremely hard and is not absorbant as the molding plaster is.

I might just get a bag sent to me  UPS as I don’t want to order a pallet load of material right now.

 

 

 

Various

I have  the Nashville clients’ project finished, with the last two crates shipping in the morning, and the city pool projects’ concrete panel finished as well.

The concrete pool panel turned out to be a major pain unlike any other! and to think, this is a donated sculpture and it was to be a simple matter to cast the concrete into the mold I made. After casting the first one there were two things I didn’t like, one was it had a lot of fair sized air bubble holes on the surface, the other was the acid stain I’ve used so well on many concrete casts absolutely looked all wrong for this bas relief- way too dark.

Ok, so I decided to cast another one and use a different stain, same story there, lots of holes on the surface and the other stain didn’t look right either!

So I cast a third one, this time I decided to nix the stain and go with an integral concrete color, but this one too despite my best concerted efforts also had a lot of holes in the surface! Concrete will always have some no matter what you do, but this went beyond the definition of “some.”

So I re-examined the whole process to see what may have changed, then  I figured out there was only one thing I had changed from the usual and that was making use of my large powered concrete mixer to mix up the dry material. I thought about how that worked and realized it was almost certainly fluffing up the sand and Portland cement enough it was putting lots of air into it.

So the 4th try I mixed the concrete up the normal way I have for years- by hand in a rubber tub, and I decided since panel #3 was not quite as red as I was hoping for, and that I had not used the maximum amount of color yet, that I would go ahead and add two bottles of it to the 12 quarts of water for the 150# of concrete to get it a little darker.

The product can be used one bottle to 60# of concrete, I used one per 75# and kept it a little less than the maximum but more than the 1-1/2 bottles I used for #3.

Now that it cured for a couple of days I took the cast out today and it came out good, a small amount of tiny air bubbles as normal/usual and certainly nothing like what I had with #1, 2 and 3. It looks like it will turn out to be a pleasant red terracotta color when it’s fully cured and dry.

So now we know- stay away from any mechanical mixing of even the dry ingredients! I knew to stay away from mixing the wet concrete that way, but it never dawned on me mixing the dry ingredients would cause issues.

 

Hopefully in a few days I can get a photo of the panel, meanwhile my right middle finger is feeling better, after having been banged a month or so ago and the nail turning black and blue, it was half replaced by the new nail when you guessed it- it was smashed again the other day wrestling the over 100# plaster mold for the pool cast down the  stairs, I lost my footing a bit and tipped towards the stone wall and of course that finger was the one that was between the mold and the stone wall and was half scraped along the rough stone and half smashed

So here it was shortly after:

As if that wasn’t enough torture for the week, while casting the concrete I wear rubber gloves, but this time I didn’t notice the left middle glove finger tore open and as I was moving my hands around the rubber tub mixing, the fingernail caught right up against a small bit of hardened concrete and broke a small piece of nail off.

Just lovely, now both middle fingers are messed up for now!

Hopefully next weekend I can get back to the Butterfly child/Mulcaster building model, I’ve not worked on it for a while and need to finish it, but right now the thought of having these two fingers in gritty wet clay is not a good idea.

R.S. project: Nashville

A client who purchased an Art deco era theater and adjacent former store building recently contacted me for sculptures to install on the former store building. The one story brick facade of the store building was in very poor condition, enough that the facade had to be removed due to a bulge in the brickwork, and then be re-mortared back in place.

The building’ name panel was preserved but the terracotta shield above it was cracked and missing a corner of it. It was decided to replace the broken shield with an Athena keystone (the nearby street names have a Greek theme, and there is a replica parthenon in Nashville as well) Also to be added was the Webster Hall griffin panel shown below in acid stained concrete being prepared for crating to ship:

 

 

Athena is  pictured below:

 

 

Butterfly child 1152 progress

Still very busy this week too trying to get other things done between the almost constant every other days rains and now the end of summer, the least of which is re-doing the brakes on my car which required several trips to NAPA and yet more to order a couple more parts, the other is finishing up a large mold for a concrete cast for the city pool building- they already started demolition on the old place and will start construction soon so my concrete cast has to be ready for installation.

Last but not least is I switched over to a new computer system running Linux Mint and setting that all up.

I did a bit of work on this today adding more flowers, a little work on the head and some on the lower right wing, I need to bring the head out more and angle it more downward too yet but it’s progress.

Mulcaster building “Butterfly Child” panel

The Mulcaster building was once located at 1156-1162 (incorrectly designated as 1297 according to one source) Third Avenue, NYC (demolished ca 1965) on it’s facade was this spandrel panel, probably more than one:

Dates: ca. 1885
Dimensions: 25″ x 28″ x 7 1/2″

Located in the Brooklyn Museum, Gift of Mr. and Mrs. Benjamin Frost.
Description: Pressed, fired red terracotta rectangular plaque with head of youth, a butterfly-boy or girl sipping nectar from blossoms through a straw.

I decided to make my version of this 19″ high, 22″ wide which is the same proportion but a little smaller and this begins with the box form for the shape:

Nr 169 Gargoyle first cast

I made the first cast this morning from the new mold, the mold was not terribly difficult to work with but it’s very large and since the plaster shell of it is fresh it still has about 5 to 6 gallons of free water in it that has to evaporate out, meanwhile the extra weight of the water adds about 50 pounds of excess dead-weight.
I still need to cast a master to store away for future use in replacing the mold, and one for a client’s order today as well.
It took 4 gallons of water in two 5 gallon buckets mixed with the cast-stone to make enough slurry to fill the mold.
Those full 5 gallon buckets are heavy as hell to lift with the wire handle they come with, it’s about 68# each when full and I filled 2 up for the cast of the other gargoyle Nr 170 that I did yesterday not remembering exactly how much it would take. I had mixed up 2 full buckets as my notes from the last time I cast one of those indicated it took 4 gallons of water and I couldn’t remember if that was to completely fill the mold up with some left over, exactly the amount needed, or if was short, so I used 4-1/2 gallons of water to be on the safe side and those buckets wound up taking 50# and then some of the cast-stone. I wound up with almost half a bucket full left over, fortunately I was able to use part of it elsewhere on the spur of the moment.

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The first cast in the Old Limestone Grey finish.

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Gargoyle Nr 169 model

The mold was removed from the clay model last night, it was difficult to pull the rubber off since it was pretty thick/stiff in places it needed to be and a lot of undercuts and keyhole areas, the original unfired clay model mostly surviced the mold making process, only the curled tail broke off but it was a fairly clean break and it can be repaired so that eventually- I hope- when I buy a larger kiln I can try firing it.
Nr 170 did not survive the mold making process but that’s ok, I have a plaster master from it and the mold.

The models were all made from Georgie’s “Three finger jack” clay which is a cone 8-10 high fire clay, this model if I ever get to firing it will have to be slowly pre-heated around 200 degrees F for quite a while, and then very slowly fired probably over a couple of days time and then slowly cooled down under a powered-on slow schedule rather than having the kiln shut completely off at final temperature.

Nr 169 Gargoyle shell

Now I will be working on building the supporting shell for the mold today.

I just finished all of the required sections and at the moment I’m waiting for the last/bottom section to harden fully before taking the mold apart.
I decided to do the plaster shell in the modelling studio instead of the basement because with the rubber and the board the model is around 120# and that’s a bit much to try and manhandle through three doorways and then down a narrow flight of stairs.
The first picture was taken around noon, the last one around 7 PM so it’s easy to see how making ashell like this takes about a day.

Nr 169 gargoyle

I started the mold for this this morning, so the progress on that is happening, the rubber portion should be finished late tonight.

Now the rubber portion of the mold is completed, having used up 3 gallons of the compound. I ordered 4 gallons knowing that like the first one it would take more than the single 2 gallon kit, they run $200 each so this one model used up $300 worth but I have enough left over now to replace 1 or possibly 2 small corbel molds that needed replacements for a long time.
The next step is building the complex plaster support shell for this, I figure about $100 worth of materials there to complete the mold plus my time, so it’s easy to see how this size model takes around $400 in materials alone just to make the molds for, it’s easy to see why I no longer just make molds automatically of new models untill there’s a firm purchase for the cast. In this case the model was finished in 2007, had I made the mold back then it would have sat around unused for the last 6-1/2 years before even selling the first cast.
The rubber portion has an unknown shelf-life purportedly being many years, but even without being used at all the rubber eventually will chemically break down, weaken and have to be replaced at some point.

Public School 168 gargoyle Nr 169

At this time I am working on setting up this model for the mold as a client has purchased a cast.

This model was made along with four others in Dec 2007 but at the time only one had been molded, the other three awaiting specific paid orders to make the molds for due to the costs involved.
The photo shows the model being set up, the red/brown material is a non-hardening wax/oil based clay and this design needs four so called dividing shims so the rubber mold will be able to open around these undercuts. The tail curl has a hole through it, so in order to remove the mold from that a dividing wall has to be placed inside that hole so the mold can open like a coat around it. Same goes for the ears and the head/neck.

Hard to believe this has been sitting stored away for 6-1/2 years, and that it also has not been damaged since it is very soft still raw unfired, but dry clay. He weighs around 90 pounds and I have had him on a dolly in the studio, out in the front parlor, back in the studio, off the dolly under the table, and then finally down in the basement where with great difficulty I wrestled it down the stairs (keeping in mind the fragility) and now I had to wrestle him back UP the stairs to do the mold. Once the rubber part is completed he has to go back downstairs- AGAIN! to build the plaster shell since that work is so messy.

Two new designs to become available

A client tentatively wishes to purchase a couple of at present designs that do not have molds available for them, one is one of the four Public School gargoyles and the other is the sitting winged lion after those on 90 West Street- both models completed a few years ago but never molded due to lack of any serious interest in them.
These two should be available very shortly.

Just for sharing/education I thought I would describe how I usually find the scales of things from photos, which I do a lot for my sculptures.

Here’s one wall of the map room in the NY Public Library, I already know it’s 34 feet wide because I found that fact in an article, so I would first look around for something of known size, if an adult person is standing there you can use a rounded out 6 feet for the scale, in this case the only known size is the width of the room.

Now I want to find out the size of the corbels in that cornice or entablature at the top of the wall, but notice the round top pseudo window in the center means that cornice is broken and there are none across that space to count, so I made a red box across 6 adjacent corbels, briefly moved it over to the pseudo window and could tell that space would have had 6 corbels across it.

I counted 9 corbels on each side, plus the 6 comes to 24 total spanning 34 feet, 34 ft x 12 inches = 408 inches, divided by 24 corbels means each is spaced 17-1/2 inches center to center, now we’re cooking because we have a measurement to use for all the rest:

Now I imported a cropped, lightened up and slightly desaturated to reduce the shin of the gold- enlarged version of the picture into CAD software, and after scaling the picture properly using that 17-1/2″ measurement I was able to begin making measurements of landmarks to start with:

The good thing is the original picture was taken pretty straight-on, and with a minimum of paralax angles caused by taking a photo looking up at something tall, there is a little here because of the height of the ceiling, but one can get reasonably close enough measurements with this that using a little fudging will get it accurate enough for this use.

If I lacked the room width to begin with, that EXIT sign and that wall clock would be the second choice for scaling off in CAD, because those exit signs are a pretty standard size and can be determined with a search, the wall clock too but it’s a little less likely to be any standard size, but most of them around this size would be around 16″ across- it would be my last choice to scale from if I have other choices.

We see the wood cornice with the corbels is 3 feet 3″ high, the coffers in the photo due to the angle of view give us the illusion they have height we can measure just like the cornice- they do have heigh, but if we were to measure that coffer from this photo going from the top of the dark cornice up it would be wrong due to the angle- the measurement that way is actually from the projection of the cornice’s edge towards you at the camera which is measuring the room length not the coffer’s depth- thats the optical illusion one has to be careful of when scaling off photos!

I was able to extract 4 more measurements above the coffers and if one looks carefully there is another optical illusion between the two 6-1/2″ measurements because that section of the ceiling projects horizontally towards the camera just like the coffers are.

The top measurement of 1 foot 11 inches is another major molding, a concave repeating molding with beed and fluting designs, it sits on top of a 6-1/” tall egg & dart molding, the other 6-1/2″ molding is a Greek styled leaf design.

We also can see the green painted wall is 7 feet 1 inch from the wainscot to the cornice bottom, the pseudo window is 8 feet wide, and the shield over it is 2 foot 9-1/2″ wide.

So in just a few minutes we have the majority of the measurements needed, the rest can be found with other photos, and whatever is missing can be guessed at with reasonable accuracy.

This photo would provide the square coffer’s width, we can assume that one IS square and determine it’s other measurement front to back, the one to the left of it would be the same front to back, it’s width can also be found in this photo and it’s rounded corner approximated easily although very hard to see here- there is a quarter round DOME above the pseudo window and that shield is not directly over that pseudo window as it appears- another optical illusion- it’s actually several feet closer to the camera, this also tends to make the measurement of that ( 2 foot 9-1/2″ ) a little incorrect because it is closer to the camera/viewer than the wall where the cornice is, but the camera is far enough away the error is really minimal here.

I also discovered when I lightened up another photo of that cornice- between each corbel there is a lion’s head carving, and each one is holding the end of a swag which curves along the bottom of each corbel which can be seen in the above photo.

So that is the method I came up with years ago.