Colin Binnie's Workshop Jottings

Couplig Rod Jig

A little while ago I published a sketch of this device (Model Railways 1972/73 I think) but perhaps it will bear repeating.It is inspired by the draughtsman's beam compass and has two (or more) stepped locating columns which are adjustable along a rod (1/8'' dia in my case). The steps on the columns are the most commonly used frame and crank pin diameters. In use the appropriate diameters are entered into the frames and the columns locked. A pair of brass or bronze collars are dropped over the crank pin diameter. Each collar has a saw cut in the side which freely accommodates a piece of mild steel strip between the collars. A wipe with flux on the joints, a tiny piece of silver solder laid in place and a quick toasting and it's done. If the collar diameter is made the length of the rod bosses they can subsequently be filed to represent the more common split brass rod ends. I am not sure if that last sentence is all that clear so I have made a thumbnail addition to the sketch. This is a truly indispensible device which is easy to make and use. Colin B

Cranks into Wheels

Take '1gauge' iron wagon wheels or castings and modify them. I usually do this by drilling the axle hole oversize. Turn a top hat bush to restore the axle hole to size and with a large enough brim to file into crank shape. Drill holes for crankpins. File to shape round crankpin holes Press crankpin into bush with ample surplus on back. Cut spoke away locally to clear the surplus crank pin. Assemble, lubricated with Araldite. Final shaping between spokes with two part car body filler. Colin B PS That is the basic method but these make it easier 1.Make the bush from rectangular stock held in the four jaw, to reduce the amount of filing. 2. A simple washer shaped jig to drop over bush with a hole at crankpin position for getting all holes at same throw. 3. Make a pair of buttons(top hat bushes without a hole) One of large end of crank/ axle hole diameters and the other of small end of crank/ crankpin diameters. Use as filing guides when shaping cranks.

Cutting Hook (1)

Cutting Hook (2)

Draw Plate

The draw plate merely consists of a hole of the desired shape in a piece of steel through which is drawn a length of soft wire. In doing so the wire takes on the shape of the hole. Since we are talking half round wire we need to produce half round holes in the drawplate. The attached sketch should explain but I will add a few extra words. To make a half round hole we merely clamp two pieces of steel together and drill a few holes of the desired sizes along the joint. These holes need only be about 4 or 5mm deep. If we invert the top piece so that the plain face lies across the holes we have our half round holes. Take the bottom piece and with the corner of a file put in a tapered lead to the hole. Be a bit careful and leave about 2 or 3mm of the hole untouched. Rub off the burrs and job is done. Put in a piece of copper or soft brass wire of about three quarter the finished half round diameter and nip it in the notch. Oil the plate and pull the wire through. Do a bit more than you need. Repeat the dose, nipping the wire a bit tighter each time. By now you should be knee deep in half round wire. Use it for making beading, split pins, handrail knobs etc. The shaped wire can be stretched to get even smaller sizes but that is another method and another story ! Mild steel is quite good enough for our quantities of wire. My first draw plate was made from an old square door handle spindle. When it does wear out remember that there are the unused half holes in the top plate. Merely file in the leads to these half holes and transpose the blocks. Apologies for crude sketch and hasty notes but I am in the midst of trying to teach my computer manners. Colin B PS One of our requestees asked for the sketch to be put wherever it is that digest readers can access it (or was it something to do with monkeys and nuts). Would some kind soul oblige?

Gears and Gearing

Hexagon pins etc.

Rolling Mill

The Rolling Mill merely consists of a pair of old ball races screwed to a fairly solid lump of metal.  One ballrace is mounted on a fixed bush, the other is mounted on an eccentric bush.  A pair of simple pillars with holes in them act as guides.  In use the tool is put in the vice, the end of the wire from the reel is threaded between the rollers and nipped by adjusting the eccentric. Grip wire in pliers and pull steadily. In goes round wire out comes flat strip. So simple that you will make yards more than you will ever need. The strip used in the scrolled railings (see: Scroll Tool, below) is rolled from 1mm wire but I have rolled up to 1,5mm copper and 1mm soft brass wire. Note that even copper comes out as hard springy material. (Handy for brake gear etc).

Scroll Tool
(Including making of scrolled railings)

The scroll tool can be made from brass. Turn a thing like a screw with an oversized head and put in a slot with a junior hacksaw. File head to scroll shape as shown. Put tool in pin chuck,  Put flat strip in slot and wind a scroll. To do fancy ones with twisted centres tape a bit of card to the bench.  Put a pair of marks on card.  Grip strip with two pairs of pliers using marks as guide.  Twist strip.  Discard strip because twisted section is too long or too short.  Modify pencil marks on card. Twist strip to right length. Repeat ad nauseam. It may be easier if a simple pair of twisters are made from a couple of bits of strip with slots in the centre. .

The scroll tool can be used for making regular scrolls as shown in picture of coach balcony railings below.

To finish off the Twisted Scroll (see diagram below), make two pencil marks on the card the length of the twisted section. Mark the length of the finished scroll (*)  Take spare piece of strip and put scroll on one end.  Put scroll end against one finished length line. Cut the plain end to length against the other finish line.  Now unroll the scroll and mark the starting point of the scroll on card. Check that you can now wind scrolls of consistent correct lengths.  Now you can repeat the scroll winding on the twisted strips. Finally use a pair of fine nippers to remove the straight bit where the inner edge of the scroll was held in the scroll tool.

For assembly I use a block of wood with lolly sticks cut and pinned in place to act as guides. Wooden clothes pegs are useful clamps. Soldering is done with a fairly large iron of about 60W.  With a large iron the joint is made instantly and the iron removed before adjacent joints collapse.  A small low power iron takes so long to raise the joint to soldering temperature that the whole job approaches soldering temperature at once. I hope that explains what is actually a very simple job. Colin  B

Soft Jaws

When doing wheels I use a soft jaw chuck. This is surprise, surprise, a chuck equipped with soft jaws! When I have to hold something like a wheel I can turn a recess into the jaws to suit the wheel and know that when I grip the wheel it will run truly. Before I had the proper soft jaws I used these soft jaw adapters. See sketch. The machining sequence is then:- Turn register in jaws about 0.6 mm deep and blank diameter.. Face one side of wheel blank and turn outside of blank to outside     diameter over flanges for about half thickness of blank. Make note of settings and repeat on all blanks. Close jaws and trim register to suit the newly machined flange diameter Hold blank by flange diameter. Face to wheel thickness and note settings. Machine tread, noting settings. Centre and drill for later reaming. Repeat on all wheels. Machine relief into wheel face noting settings. Repeat on all wheels. Reverse in chuck. round off flange. Ream hole with stop on reamer for press fit on axle. Colin B The adapters are useful for holding all sorts of things where a register can help locate the work.

Small Drills

Small Pipe Bender

Soldering

Tee Sections in Brass

Here are three simple ways of making brass tee any one of which should occupy no more than twenty minutes. 1. Fold up from sheet. Soften brass sheet by heating to red heat. Quench or allow to cool naturally,doesn't matter. Clean up. Fold double and nip joint in vice. Straighten folded edge. Put back in vice and fold bottom flanges. Run soft solder into crease and trim flanges. OR 2. Fabricate. Take the brass strip that is to form the stem of the tee and bend the ends at right angles. Lay it on the strip that is to become the top of the tee. Anoint with flux and silver solder Trim flanges. OR 3. Mill from solid. Colin B PS Methods 1 and 2 produce soft brass tees that can be formed into fancy shapes. Method 3. will probably be from free machining brass which is more rigid. There are dozens of other ways of making tees but if you only need short lengths these are the obvious ones.

Wire Rings