Attachment to boiler

At the base of the column there is the problem of joining a glass column to the 3A" pipe nipple on the boiler and you will require the services of a machinist to solve this problem for you. Glass-to-metal joints are always tricky, so four different arrangements are shown in Figures 8 (a), (b), (c) and

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3/4 " nipple

Standard taper joint

Standard taper joint

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3/4" nipple

Ball & socket joint Compression joint


(d). In the first case (a) a teflon O-ring makes the seal between the base of the column and a brass adapter specially made with a groove on the top plate to match the groove on the end of the glass column. A clamp is necessary to hold the two halves together, the top one being a ring which the glassblow-er must include before he fuses on the O-ring joint.

The next (b) requires the glassblower to fuse a 34/45 standard taper joint to the bottom of the column and the machinist to make a corresponding female half of the joint from brass. The angle of the taper is 21/z degrees. A thin teflon sleeve must be used between the metal and glass in this joint, identical to the one between the top of the column and the stillhead.

The third (c) glass-to-metal joint uses a glass ball at the base of the column (size 5%0) which nests in a brass socket, made by your obliging machinist. A thin gasket of teflon film produces the seal between the glass ball and the brass socket, or you can use a teflon-based plumber's grease which comes in a tube like toothpaste.

The fourth and last adapter (d) uses a specially made compression fitting. It has the advantage of being able to use a glass column cut off square at the bottom, which is much cheaper than using a glass standard taper or ball joint. The compression fitting, which is similar in size and principle to the sort used to attach the tailpipe under a sink, must be made by a machinist. This joint, using a compression fitting, is our personal preference.

The chances are, after reading the above, and after hearing that the cost might be around $1,000 for a glass column, you will opt for one of the metal designs. For this reason we have not gone into more detail.

Making Your Own Wine

Making Your Own Wine

At one time or another you must have sent away for something. A

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