This is the bore in the head stock housing that receives the quill. Note that it is not necessary to bore out the diameter and sleeve it. The bore is simply roughened with hand tools.

Since the spindle bearings are contained inside of the quill, heat will be generated causing the quill to expand. The head stock is not likely to expand as quickly. For this reason is necessary to allow extra clearance between the quill and bore to avoid seizure due to heat. Here the quill has been sprayed with a release agent that builds up a coating thickness on the order of .003 of an inch.

Here the quill has been inserted into the head stock. The exposed perimeter of the molding area has been sealed using foam weather strip and STF rapid curing material. The quill has been checked for squareness to the positive side of the head stock. Note also the injection ports indicated in the side of the head stock by protruding plastic tubing.

Moglice is mixed and injected into the void with a caulking gun. The injection process is started at the lowest point and progresses upward until the Moglice flows out the vent at the top.

The elevating screws for this 14 ton head stock were also rebuilt using Moglice. The babbitt in the old steel nut housings was melted out. The nuts were then bolted in position, the screws which had been re-chased are inserted through the nuts and centering rings that pick up the outside diameter of the screws were used to align the screws parallel to the positive sides of the head stock.

By pushing the screws axially through the nuts, the total clearance or backlash was determined. The screw was then positioned in the center of this clearance. Temporary threads on the back of the head stock were molded with STF material. This allows for the screws to be screwed out of the nut far enough to be sprayed with a release agent and then screwed back into the nut without the screw hitting the internal surfaces of the nut, which would damage the coating and contaminate the adhesion surface with the release agent.

The ends of the nut are sealed with modeling clay and the Moglice is injected. The main bore and all four nuts were injected in one day.

The next day the nuts were removed from the screws by warming them slightly and then trimmed. The measured backlash was the desired .002 of an inch. It is possible to mold large nuts with less than .0005 of an inch clearance. Again, be careful of temperature rise as heat from heavy loads can cause a nut to seize. Please see our engineering handbook for more details on the replication of nuts.

This is a view of the finished bore after removal of the quill. Please note that no boring, scraping or honing is required on the Moglice surface. This procedure saved the cost of building up and re-grinding the quill, of boring out the head stock, of sleeving it and especially the headache of trying to match machine the quill and bore. And certainly boring an accurate hole in the head stock would have been much more difficult and would have required further disassembly of the head stock.