A Combined Toolholder and Traveling Steady

for turning down long pieces of steel tubing to make reamer pull tubes

. Tap 8-32, 2 places, for screws to secure toolbit in place

0.130"

. Tap 8-32, 2 places, for screws to secure toolbit in place

0.130"

Set Screw Dimensions

tap 6-40 for adjusting screw to advance tool bit

5/16' deep x 0.260" deep slot to take a 1/4* square toolbit (shown by dotted line).

tap 6-32 for set screw

«« NOTE: This hole should be .made at an early stage in the ¡making of this device. When the toolbolder/steadyrest is done, this hole takes shop-made bushings which are bored to take whatever size of steel tubing you may need to turn down to make a reamer pull tube of a particular size.

tap 6-40 for adjusting screw to advance tool bit

• NOTE: Not critical. 3/4" sq. is Tine, but 7/8" sq. would be okay too. Bill's happens to be 3/4" x 0.838". Make from cold rolled steel or similar.

5/16' deep x 0.260" deep slot to take a 1/4* square toolbit (shown by dotted line).

• NOTE: Not critical. 3/4" sq. is Tine, but 7/8" sq. would be okay too. Bill's happens to be 3/4" x 0.838". Make from cold rolled steel or similar.

Rifling Machine

tap 6-32 for set screw

«« NOTE: This hole should be .made at an early stage in the ¡making of this device. When the toolbolder/steadyrest is done, this hole takes shop-made bushings which are bored to take whatever size of steel tubing you may need to turn down to make a reamer pull tube of a particular size.

Before you can ream a drilled barrel, you will need to make a steel tube of a suitable size for the caliber of barrel you are making. This pull tube, as it is called, is silver soldered to the reamer, and serves as both reamer shank and oil delivery tube. Now obviously turning down a 30" length of 1/4" OD steel tubing to say 0.230"<f> is not a job one would normally relish having to tackle However, the tool shown above makes it easy, and is simple to make.

The device mounts in the lathe toolpost, carries its own toolbit, and acts as a travelling steady. Make a bushing with about 1 thou clearance on the particular piece of tubing you have to turn down to size. Once you get the bushing made, and bfore you go any further, check that it will slide nicely along the full length of your piece of tubing.

This device steadies the tubing, while the toolbit within the device cuts it down to the desired size. Set up with bushing on center height of lathe, and leading the toolbit slightly; adjust the toolbit so its cutting point is at exact dead center height on the tube, and set so as to bring the tubing down to the desired size. A little cutting oil wiped onto the tube before you start the machining operation is also a good idea.

Very few of the dimensions shown are critical. You will want to measure a few things about your own lathe/toolpost/toolholding system, and then draw up something similar that will fit your equipment.

As Bill says on the video, he found the idea for this device in Model Engineer Magazine, but he does not recall in which issue, or who the author was. I believe the idea is from Alan Mackintosh, and if so, the article was in M.E. for April 19th, 1974, page 403. Alan Mackintosh is also the designer of the pantograph engraving machine detailed in my book The Machinist's Second Bedside Reader (US$21.95), along with a number of other ideas in that book and in The Machinist's Bedside Reader ($19.95).

IN-HOUSE GUN DRILL SHARPENING

Machinist Bedside Reader

these are the various title cards from the video

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