I have created a Gallery which can be accessed by clicking on my Traction engine avatar and will place various files related to the build there.

One thing that cropped up in the earler thread was the cost of materials. I have prepared a Bill Of Materials, the second page of which is a “shopping list” of what should be required in the way of materials, fixings, etc for the engine. Pricing these up against the current M-Machine metals price list, Modelfixings Website and a couple of websites for the springs and O rings the cost as of today should come in just under £60.00 which compares quite favourably wth the Stuart V Twin kit at £169 and that for a smaller 7/16″ (11mm) bore engine.

Note as my engine is only likely to get the occasional short run I have taken the “for display” option and used 6082 (HE30) aluminium for the main Y shaped standard and bearing block but pricing is based on using brass for a working engine. I allowed for 300mm lengths of the smaller section material and suitable 25mm increments of the larger items. This should hopefully morph into Kelsey over the next few weeks.

Also in the gallery I will keep an updated PDF of The Drawings which will be added to when more parts have their 2D working drawings produced from the current 3D modeled parts.

I have tried to keep cutting tools to a minimum but these are likely to be most of what will be needed to make the engine

From Top Left

6mm and 3mm diameter 3 or 4-flute milling cutters

Small countersink bit

Spot Drill approx 4mm dia (Centre drill will do)

M3 and M2 taps, preferably spiral flute but traditional 3-piece sets will do

M2 and M3 Dies

On the Right

1.6mm Drill bit (M2 tapping size)

2.0mm Drill Bit (M2 Clearance)

2.5mm Drill Bit ( M3 tapping size)

3.0mm Drill Bit ( M3 Clearance)

6.0mm drill bit if drilling main bearings

5.8mm Dril and 6mm Reamer if reaming main bearings. See subsequent text

2.8mm Drill and 3mm reamer if reaming Pivots and end covers. See subsequent text

Depending on the chosen steam/air connections a suitable tap & die will be needed and can also be used for the piston rod gland nut if fitted. See subsequent text.

Note that those who have a good selection of imperial equipment may want to substitute the 3mm and 6mm diameter material with 1/8″ and 1/4″ in which case 5BA taps & die will be needed and the M2 threads can be replaced with 8BA

Good to have you onboard Jim.

Well it seems the forums gallery is not going to be the best place to post the drawings as the links will be broken each time I post an update so I have not placed them under the “workshop” section of the forum which can be found on the blue bar at the top of the page or just go straight to the item by clicking here.

I have laid these ones out a bit differently to my other sets of drawings where I tend to use the parts centre line as the datum, instead I have use da corner or edge which should make it easier for those with limited equipment, as I will show in the build.

Talking of showing there will be a lot of photos which I feel can convey more than a lot of words if some of those engineering words are new to the reader. So far I’ve about 60 images and not even finished the second part!!

………..Cont

With all the drilling done the next job is to form the cutout which gives clearance for the crank thus keeping it a slow as possible for a shallow propshaft angle if used in a boat as well as keeping the centre of gravity low. Use some marking blue or in this case a sharpie so the scribed lines show up and put the shank of the 6mm drill bit into one of the holes. Bring the blade of a tri-square up against the drill shank and that gives the correct position to scribe your line, repeat for the other two.

The waste material can then be sawn out keeping about 1mm from the lines. I used a hacksaw to do the two shorter cuts and then managed to get a junior hacksaw in to cut the long edge. The part can then go back into th emill vice against the stop and a 6mm milling cutter loaded into the collet. Using the same co-ordinates that positioned the two 6mm holes the three edges can be milled to final size.

You could call the part complete at this stage but it looks nicer if the external corners are rounded over, I have shown a 5mm radius for all of these. Although they could be milled with the aid of a rotary table I doubt many beginners will have one so good old “filing buttons” can be used. These are nothing more than a piece of rod with a diameter twice that of the required radius and drilled to match so 10mm diameter in this caseand drilled to suit the hole which is 3mm this case. Drill deep enough to make two buttons about 4mm wide which can either be sawn or parted off. Pause the parting cut part way through to remove any burrs on the edges. Anything will do for the buttons that is to hand, I used 10mm mild steel but any metal will do and larger can be turned to 10mm diameter.

Saw of 25mm or so of the 3mm silver steel that you bought for the engine to use as a pivot for the buttons and slip it through one if the holes and then place a button on either side. To stop the buttons falling off I wind a small piece of masking tape around each end of the pivot rod.

The filing action should be in line with the base plate not across it. Start with the file fairly vertical and as you cut bring the handle down so the file is almost flat at the end of the cut.

As you reach the 5mm radius the file will start to roll on the buttons which stop it taking off mor emetal than wanted so just work your way around until it rolls in all positions after which th ecorner should look like this

A strip of emery cloth backed by the file can be used for that final pass. The inner curves of the cut out will be a bit more fiddly as you can only use the end of the file, however some roughing out can be done with the file across the work making sure not to go too deep and score the buttons.

I have shown the top edges of the plate with a small radius, the is best left until the other parts are in position as you may not want to have the radius run all round. So at this stage the first completed part should look like this.

The Standard

A first glance of the drawing for the standard on page 3 may look a bit daunting and I have only put a few overall dimentions on it. However the latest version of the drawings have now been uploaded and the budding builder can see that I have broken the job down into several stages all with their own drawing detailing that stage.

Looking at the BoM you can see I have specified 1/2″ x 2″ flat brass bar for a working engine or the same size in 6082 aluminium for a shelf queen. The 4″ length suggested will also provide material for other parts so the first thing to do is saw off a piece a little over 80mm which is the overall size for initial machining shown on drawing 4

The drawing also shows the initial machining height as 50mm which is what will be tackled first.

It should go without saying but for those new to the hobby that a mill vice should be set parallel to the tables axis, this is best done with a dial indicator against the fixed jaw so that the needle shows the same reading as the vice is moved from one side to the other. I’m also assuming that the mill is reasonably trammed eg the spindle if perpendicular to the table both sideways as well as front to back. The same applies if doing it on the lathe, set the vertical slide true across the lathe and the fixed vice jaw horizontal.

Take a measurement accross the 2″ width of the bar, deduct 50mm from that and half the remainder and that is what needs to come off the first side, in my case the bar measured 50.9mm so 0.45mm.

Making use of one of the factory edges set that against the bottom of the vice, Load the 6mm milling cutter and lower the mills head (or raise the knee) until a couple of mm from the top of the bar. Gently bring the cutter down to touch the work, lock the quill and zero the height dial or readout.

Raise the head and move the cutter clear of the work, lower back down past zero to 0.45mm and machine the top face of the bar, I used three passes of about 4mm width each. A sharp cutter should produce minimal burrs, if not find a sharp one. The brass can be cut dry but a little paraffin or WD40 applied to the aluminium will help with the finish.

remove the metal from the vice and measure the remaining width and note how much neds to come off to arrive at the desired 50mm, I’d like to say this was skill but more luck on an initial cut.

Put the metal back in the vice with the freshly machined face down. Lower the tool by the amount needed to come off and machine the top face. You now have a 50mm wide bar with sawn ends

There are two ways to deal with cutting the ends, the bar could be held flat and the side of the cutter used to machine the end which I often do but I’ll show the other option which would be more suited if using the lathe. Put the metal in the vice with one sawn end facing upwards and just nip it up, use a tri square against the newly machined edge to check it is vertical and when happy tighten the vice, a light behind can make it easier to tell if there is any gap between work and square.

If doing it in the lathe then you can either hold the work in a 4-jaw, or in a vice mounted to a vertical slide. Again use a square to line up a previously machined edge, light cuts as there is a fair amount of stick out say 0.5mm max. These methods could also have been used for the earlier cuts and also the work to come.

Use the 6mm cutter again to just clean up the first end, then put that on the bottom and clean up the other end. Take a measurement of the length and then make one or more passes to arrive at the final 80mm. I had about 1.4mm to come off so did a pass at 1mm deep then a second at 0.4mm deep.

Cont………

…… Cont

Rather than start the other holes on an angled surface it will be easier if the two top corners are milled to 45degrees first. Set the work in the mill vice using something to set the angle. I am using a digital angle block but a set square out of a school geometry set will do.

Load the 6mm milling cutter again and bring it down so that one of the teeth just touches the corner and zero the height scale.

The top corner can now be milled flat to a depth of 8.1mm, I did in in 2mm passes then a final 0.1mm finish pass. Repeat for the other corner

Reset the work at 45degrees but this time with the bottom corner also touching the stop. Relocate the 3mm offset position which you made a not of the handwheel setting for and come sideways 30.9mm. Spot and drill 3mm until you feel the holes meet, repeat for the other side by flipping the work front to back.

The last pair of holes are done again by mounting the work at 45degrees but this time with one of the angled faces against the stop. sideways offset is 44mm, repeat for the other side.

Next time I’ll cover drilling the other holes that come in from the front and rear faces.

The final few holes are drilled from the other side so turn the part over and locate against the stop, move 35mm in Y and 40mm in X. Spot, drill 2.5mm for a depth of 8mm and then tap M3 using the tap guided so that the hole is as true as possible.

The two 3mm holes can be spotted and drilled 3.0mm to the required depth to meet the passages

Much like the other side this one can now be milled all over to bring the part to the final overall thickness of 12mm and thus ensuring the regulator face is suare to the hole for it’s pivot shaft.

At this stage the builder has the option to just leave the whole standard at 12mm thick or reduce the thickness to leave just the cylinder and regulator contact areas and a ring around the crankshaft hole proud of the surface. This is how to go about the machining if you choose the second option.

Starting with the easier regulator side first mount the job in teh 4-jaw chuck and set the regulator pivot hole to run true. I’m using a sprung centre in teh hole but the long length of 3mm material on teh BoM will also do. Rest the Dial indicator anainst the end of teh rod and rotate the chuck by hand making adjustments to the jaws until th eneedle hardly moves. The work is resting against the two reversed jaws so that will stop any wobble affecting teh readings and also the thickness of teh cuts.

A standard turning tool can be used (right) but if you really want that “cast look” then something with a bit more radius to leave a filler in the corners works best. Either a HSS tool ground with a rounded end (middle) ort an insert with more corner radius such a sthe one shown with 0.8mm radius (Left)

Touch the tool against the face of teh work and zero the cross slide dial, move clear and start the lathe.

Feed in the top slid 0.5mm and start facing the work, stop as you get near the 17mm diameter and zero the cross slide dial. Take a measuerment and work out how much more needs to come off then start the lateh again and using the handwheel dial take what was needed off.

Back out the tool and put on the final 0.25mm depth with the topslide and take one smooth cut right upto the 17mm dia edge.

The other side is set up in a similar way getting the crankshaft hole to run true, as the hole is larger I use a morse taper centre in the hole with it’s “blunt” end supported by the tailstock centre. Put a couple of Sharpie marks about 28mm from the diagonal corners as the turning wants to stay within those lines.

Swing teh tool around a bit and this time have the work turning as you put on the two cuts while at the same time feeding in with the cros sslide, this will “ramp” the cutter down to depth. You can see I have an area 4-5mm wide all around the 12mm raised boss.

To be continued.

Any questions, comments,etc or am I talking to myself?

Must admit I had missed your second comment as it fell between two postings and we don’t get the warning hear that other posts have been made while typing. Though we don’t seem to get many comments on builds here a syou probably know from your own posts.

As i don’t mark out much the sharpie marks can help to know you are in the right sort of position, I was also working from a preliminary drawing with all the holes on it so a lot easier to make a mistake.

But I try to put a few tips and reasons why I do things the way I do into these builds in the hope they will be useful to others. Sometimes I have to think twice as there is little point in my using tools that a lot of beginners may not have so need to go back to basics. If it were not for that I think the engine may be running by now but it’s not far off.

Thanks I forgot to mention about the packing, will go back and add something.

If they look as good as your other one then it will be worth the wait!