Tibetan Water River Horse XL: Tail-to-Rump Connection

MPF Conservation assessed the Jantzen Beach Carousel in 2018, and subsequently treated three horses and several decorative objects from the carousel.

This page is about the carousel restoration treatment for “Tibetan Water River Horse XL” (hereafter called Tibetan) from the Jantzen Beach Carousel, and shows treatment on Tibetan’s tail-to-rump connection.

Note: Throughout MPFC may switch from flash to non-flash images,
because we are trying to show the best image of the treatment.
Videos to recap the processes are located at the bottom of this page, and on Vimeo.

Tail-to-Rump Connection

Tibetan’s tail was loose from his rump. When moved touched it felt as if it would sheer away at its connecting point. MPFC performed initial inspections by running magnets over the tail’s connection points in order to ascertain the probable cause of the problem. Both tests provided information which allowed us to postulate the presence of metal wraps, nails and rotten wood.

Below, the last generations decorative paint prior to our excavation; this is a beautiful painted dappled patterning, and we were sorry to for the necessity of paint removal!

MPFC decided to carefully remove the paint around the tail-to-rump connection using a non-damaging monofilament wheel, which spins at high speeds and lifts paint while leaving the wood intact.

Once the tail-to-rump connection was visible the problem became clear. There was catastrophic rot in the rump and well as severe damage from both nail repairs and the introduction of metal bandages over the compromised area. Metal oxides combined with fungi, bacteria and water (from cracks in the surface paint) causing the historic tulip poplar to petrify and turn to rubble.

Once the paint was removed, thin copper cladding and tin strips revealed, along with many nails. Uncovering the cacophony of old repairs was the precursor to the discovery of extensive structural damage beneath the patches.

Mitchell carefully began the painstaking extraction of the dozens of rusting box nails, above. This was slow work!

The cladding was slowly peeled back.

The actual tail-to rump connection was exposed, above.

When the cladding was removed, the rotting, petrified surface woods were exposed, showing a mummified mess.

Initial measurements were taken while the tail was still attached. Later patterning / mapping of the original trajectory of the tail tenon, the mortise, and the connection occurred.

Tibetan’s tail tenon was extracted from the mortise, revealing rot and rubble deep in the mortise.

Tibetan’s tail tenon rot extended into the carved details of his tail, all of which were covered by cladding, above. Note the many many nails still in the tail.

Mitchell pulled large rusting construction nails from the tail, above, presumably used in the last few decades to hold the tail in place. Construction nails are not appropriate nails for this application.

Mitchell began mapping and calculations of the rump’s contours around the disintegrated tail mortise, above.

These would be invaluable when the area was excavated and rebuilt.

Above, a clear vinyl tracing and map was created of Tibetan’s original tulip poplar slab laminations. These planks were part of the formation of the torso structure. It was important to be able to identify their original position.

Tail-to-Rump video to give you special effects, above!

Mitchell used a specialized boring jig which could be preset and conform to the original mortise, above.

The mechanism attached to the rump by clamping to a temporary bendable plywood fence Mitchell built attached to Tibetan’s rump. The plywood fence also acted as a determining line for the plunge saw blade which would ultimately excavate the rotting rump materials.

A second vinyl tracing/map of the intended are of excavation was created, right. These clear overlays, one on top of another, assisted him in the proper placement of his cuts.

Above, before the final cut to remove the blocks, Mitchell used gap filling glue and hard picks to fill enough holes so the blocks would not become a pile of unrecognizable rubble when removed.

The picks were left to cure in place overnight, then trimmed, left.

Mitchell created a plaster mold of Tibetan’s rump within the confines of the cutting fence, above and right, both for historical record and also to assist him, as necessary, during the carving phase.

Mitchell began excavation of Tibetan’s rotted rump by using the plunge saw which was guided by the temporary fence, image one above. The excised chunks were removed, saved and laid out to act as three dimensional models for the recrafting process.

We wear masks because of the potential mold associated with many of our projects.

Tulip poplar blocks were created with a grain pattern compatible with surrounding historic wood grain. These blocks would eventually become the new rump section. They were slowly and methodically contoured, while loosely fitted in the cavity, as the rump assembly evolved, and were completed during the tail fitting, below.

Note: This was not all performed at once in a linear fashion, though we show these grouped together. Instead, Mitchell moved from tail to rump as the new parts evolved or had to cure.

Mitchell repaired the internal shrunken blocks of the substrate using gap-filling glue and a hardwood shim, above, allowed it to cure then trimmed the hole for the tenon.

Tenon fitting, left, while a terrified baby water snake looks on; Mitchell reassured him it was all right! Unlike working on a cabinet, there is a certain amount of connection made when working on the life-like beings.

The new tenon was laminated to fit the historic mortise using veneer. Veneer was wrapped to the proper dimension, glue applied, and then the veneer was clamped during curing using hose clamps, not shown.

Mitchell cut the damaged butt join of Tibetan’s mid-tail section from the body of the tail in order to replicate the tenon and top part of the tail, above.

After seeing the way Patriotic Jumper XL‘s tail was constructed, he chose to replicate Parker’s manner of connecting two blocks in his repair. He chose stainless steel pins to join the historic bottom of the tail to what would be a new tulip poplar replacement, shown above and right, as Parker did.

The stainless steel pins had to be fashioned to penetrate the new poplar by creating pointed nibs.

The tulip poplar was chosen for compatible grain structure and direction for the new replicated part. Holes were marked and drilled on both the historic tail and the new poplar block, above.

The historic tail section was prepped and glued onto the tulip poplar block, above.

The new “tail” was set into a table anchored jig and held tightly clamped in stasis for 72 hours while curing.

Mitchell placed the new “tail” into a bench vise and began shaping the block into the top of the tail, above.

A drilling jig was created for these tails to hold the repaired tail in the exact original angle of the historic tenon of the mortise bore.

Mitchell bore through the fresh material to set the tenon, above.

Mitchell carved the terminating tip of the tenon to a precise diameter where wood-to-wood contact was tightly compressed when inserted into the mortise.

The deeper mortise below the rump “chunk” that was created in the historic substrate was also filled so that when the final deep drill was performed for the tail tenon to be finally inserted into the new and old parts, the mortise would be snug, above.

The vinyl overlays or maps were now coming in handy for marking final placements on the new poplar chunks, example shown left.

Mitchell again used the boring jig to drill the final tenon-to-mortise bore into the new rump blocks and into the restored historic interior planking. The procedure was successful. the outer rump bore now matched the interior which allowed the new tail tenon to reach deep into the depths of the rump, assuring strength for the tail and also making certain the tail angle was identical historically.

Above, the cutting fences were removed from Tibetan’s rump.

Gap-filling glue was brushed into the cavity, and the fresh tulip poplar rump infills (chunks) were set into position, one at a time.

Holes were filled with hardwood picks both around the rump inset and some in the inset area, above, prior to the top half inserted.

The tulip poplar chunks were additionally secured with vintage brass wood screws, shown above and below, by creating a countersink through the new poplar and into the historic rump, then plugged with hardwood plugs and leveled.

A small additional bit of tulip poplar was added above the tail, shown above and below.

Mitchell shaped the rump block and the final image above shows the shaped blocks with a tail tenon being fitted.

1lb platina shellac sealed the new wood to minimize shrinkage during the application of gesso and new paint.

A final fitting of the new top tail into the completed rump before shaping, above.

Slight modifications were performed on the tail mortise stump, however, the fitting was a success! Wood to wood contact was achieved.

Mitchell was able to locate the exact angle of the tail relative to Tibetan’s rump and set a line onto the fresh tail section for carving.

Mitchell began shaping Tibetan’s fresh tail stump, above. Patterns and images taken allowed the fresh tail top to be a good replication.

The tail tenon was fitted for a screw hole, above. This is important, because in future if any work needs to be done to the tail then a simple screw can release the tail for repairs. NO glue will be used in the final tenon fitting. This is the type of reparation that all the horses should have, to make future issues an easy fix.

Mitchell marked the line of the tenon placement for the screw to work properly, left. The screw hole was eventually fitted with a wood plug, not shown.

Note: Originally Parker intended for this to be the way the horses were repaired, and we have seen other slight indentations that indicate a fitting like this one, though some have been covered up in incorrect repairs.

Above, Tibetans’ tail top after the bulky portions were removed. Final shaping of the tail was performed using several tools, including a veining chisel to replicate Tibetan’s hair strands.

Mitchell brush coated the tail top and all the exposed wood areas with one more coat of 1lb shellac until paint could be applied..

Below, several videos that recap this process (and are also posted on Vimeo):

Tail-to-Rump 1

Tail-to-Rump 2

Tail-to-Rump 3

Tail-to-Rump 4

Tail-to-Rump 5

Tail-to-Rump 6

Below, two more pages that discuss other repairs on Tibetan Water River Horse XL: