The Workshop Progress Thread

[Colin HeseltineParticipant @colinheseltine48622]

Ketan,

The magnetic tape is enclosed within the aluminium strip. The main aluminium backplate is a piece of 25mm x 3mm flat bar. This has fixing counter-bored fixing holes every 200mm and at the same 200mm spacing a pair of 3mm tapped holes, one above and one below the main fixing hole. A 25mm x 2mm cover is then fitted using the 3mm holes. The cover has countersunk holes for the fixing screws. The cover plate has a recess machined down it's length 10mm wide by 1.5mm deep. The magnetic strip sits in this recess. I believe that the magnetic strip could just be stuck to a flat surface as it has an adhesive strip on the back.. The other possibility is to just fit the cover flat over the magnetic strip. Doing this would only lose 2mm depth of travel.

Because the table on the Cowells Mill for example is only 27mm deep I elected to use the backing strip and cover, plus it needed to extend a further 70mm past the end of the table and so required the support. The way I have it installed on the mill I only lose 7mm of rearward travel for the table which is no big issue.

On the Lathe because I needed jacking screws to get the magnetic strip both vertically aligned to the read head and parallel to the lathe bed I again needed to use the backing support strip.

I have had no issues so far with swarf getting between the read head and bar. On the mill the gaps is around 5 thou (0.13mm) and on the lathe it is around 10 thou (0.25mm) This compares to manufacturers tolerance of .1mm-1.0mm.. Because I have the gap so small there is I hope not much chance on swarf being caught between the two faces.

I do not use coolant, the two machines are in my recently newly carpeted office so coolant is a no no. The read heads are IP67 rated, so totally protected against dust and protected against immersion of 15cm to 1 metre.

Regards,

Colin

[Ketan SwaliParticipant @ketanswali79440]

Thanks for the detailed reply Colin.

Ketan at ARC.

[JasonBModerator @jasonb]

Now that I have polished up my balls I feel happy to show them in public, also got the various pivots, levers and links done that transfer the novement of the governor up to teh butterfly valve on the valve chest.

[Ian S CParticipant @iansc]

That's a fine pair of balls you have there Jason, should be quite uplifting.

Ian S C

[JasonBModerator @jasonb]

Thanks Ian

With the ball done it was time to make a start on my cocks, cut from 5/8 sq brass.

Plus a bonus photo for Andrew J

J

[Ian S CParticipant @iansc]

Those balls would make good decorations for the Christmas Tree.

Ian S C

[ianjParticipant @ians]

Thought I would share with you a short video of my Hit & Miss engine running.

It's The Farm Boy built from Jerry E Howell (USA) plans using bar stock ( Aluminium from local Non Ferrous scrap yard) most of the other material I already had. The only castings are the fly wheels which I had cast locally using a partly machined one I purchased from the Home workshop ads as a pattern, It involved cutting two gears which was a first for me

It's running using a minimag Co. coil & miniature ignition module, a 70%/30% mixture of colemans fuel/methanol.

I think I'm hooked on hit & miss engine now !!

**LINK**

Ian

Edited By JasonB on 19/12/2015 13:16:45

[JasonBModerator @jasonb]

Looks to be running well but would be nicer with some sound. I think the Farm Boy is by far the nicest of the barstock hit & miss designs, are you intending to give it a lick of paint?

J

[ianjParticipant @ians]

Jason,

Yes I intend to paint it .I'm thinking sateen finish dark green.

There's a reason for no sound. At the moment there is a tight spot between the two gears and it makes an annoying squeaking sound, I'm hopping this will disappear after a bit of running in?

Ian

[JasonBModerator @jasonb]

Some people put a bit of valve grinding paste on the gear and run them in that way, not tried it myself though.

I don't think the farm boy has it but several of the hit & miss engines that I have done have the end of the timing gear stud turned eccentric to the shaft so you can just rotate it slightly to adjust the mesh of the gears

Edited By JasonB on 19/12/2015 13:32:18

[JasonBModerator @jasonb]

Seems I have spent most of the weekend playing with my cocks but I'm happy with the outcome.

They started life as some salvaged 5/8" sq brass and were carved from that with just the spout thread being a soldered on piece (no room for a die)

And a pic of the tapered reamer used to form the conical hole which was turened at the same setting as the spindles which were lapped in with 600g powder and seems to pass the blow test.

[Neil WyattModerator @neilwyatt]

Like both of those (engine and taps).

Neil

[Anonymous]

Having spent part of yesterday slogging away on the Bridgeport machining heatsinks for a client this evening I was able to construct another Heath Robinson setup to machine the water pump spigot for the bypass valve:

The spigot is machined to length and diameter, drilled though and then opened up to form a flat bottomed hole, using a home made D-bit. Finally the outside is screwcut 3/8" BSP. This is a rare chance to use the small faceplate – it's not that well endowed with slots. Despite the helpful sticker giving a top speed of 1200rpm the machining was done at a more sedate 260rpm. Now that everything is set up it shouldn't take long to swap over castings and machine the other two water pumps.

Interesting to see the nifty cocks made by JasonB, and the strange brass swarf. For the water pumps I need to make some elbows, which will need silver soldering. The elbows will only see warm water, so could be brass, but I wondered about gunmetal. My normal supplier of gunmetal states that it is leaded. i know that using lead based solder prior to silver solder is bad. So does that mean that leaded gunmetal may not silver solder properly? This question will gain importance when I get around to the other boiler fittings, some of which will definitely be seeing steam.

Andrew

[JasonBModerator @jasonb]

Andrew, just seen your post, must have missed it earlier. The cylinder that I showed earlier and that you have seen in the flesh is leaded bronze SA660 and soldered OK, same with a lot of the fittings on my Fowler. Can you not drill round the corner of your elbows and therefore make them from solid, I managed to do that on teh drains and always do it with the cast elbows that I use on the hit & miss engines.

More Baubles as its christmas, this time the cylinder lubricator, the valve was done in much the same way as the drains, just a quick regrind of the form tool and I had made the third spindle at teh same time as the others so could use the same taper reamer. I did make my own ball this time, 1.25" dia and hollowed out.

Also plumbed up the drain cocks

Those with a keen eye will also spot that the governor drive pullies and belt are in place and I can confirm that it is a working governor

J

 

Edited By JasonB on 26/12/2015 20:26:30

[Anonymous]

Looking good Jason – where are you getting the designs from? Are they on the drawings or to your own design? I was wondering why nobody had picked up on my question. It was beginning to look like no-one was reading the 'Workshop Progress' thread, which would be rather ironic given the recent fisticuffs bemoaning the lack of engineering input on the forum. From a combination of sources it looks like silver soldering LG2 should be no problem. I don't understand what you mean by drilling round the corner?

Apart from mucking about with the PathPilot installation on the CNC mill today I also machined to length and rolled a new front wheel rim to replace the duff one. Here are the home made rolls and said new rim:

I've also cleaned up the large scrap aluminium plate ready to be used as a jig for building the wheels. The plate was cheap from my normal aluminium supplier as I asked for a minimum size, didn't care about thickness and most of all didn't care about gouges. It's win-win, they can get more than scrap price and I get it much cheaper than normal.

Andrew

[John Stevenson 1Participant @johnstevenson1]

Andrew,

More details please of the rollers.

How do you get the ring out after rolling and what thickness is the rim you rolled.

[JasonBModerator @jasonb]

Andrew, I'm working from some photos of an original engine taken by another forum memmber, (you may have seen his full size one at Fornsett or in ME recently) and also the odd photo found on the net. I have drawn it all up from these at 2/3rd scale and it will be featured in ME along with a full set of drawings.

 

On your fittings would it not be easier to use bronze bar as its a bit harder than gunmetal and readily available in various round bars? By drilling around the corners I wa srefering to drilling in from each end of the elbow so the holes meet in the middle and hopefully don't come out the other side. That is how the drain cocks were done

As were these elbows & tee

Edited By JasonB on 27/12/2015 07:58:56

[KWILParticipant @kwil]

Andrew, LG2 silver solders fine

Jason, those fittings look great

[Anonymous]

After wasting a good portion of the day trying to get tool offsets working in PathPilot I managed to salvage something by marking out, drilling and tapping (1/2" UNC) the fixing holes on the jig plate for my traction engines wheels. Only the holes needed for the front wheels have been done so far, but they'll keep me busy for quite a while.

Andrew

[Anonymous]

John: The rolls were specifically designed for rolling the rims of my traction engine wheels. The rolls are a bit over 2" diameter and the gears are 13 teeth, 5DP. The front rims, as seen in the picture, are 3" by 1/4" and the rears are 5-1/4" by 3/16". To simplify the design the rolled metal goes down under the mill table. A CAD model showed that there was enough clearance on the front wheels (14.5" OD) to do this. Again to simplify the design the rolled rims are simply opened up enough to clear the rolls to remove them and then allowed to spring back.

In the event I didn't roll the rear rims on these rolls as somebody on another forum kindly offered me the use of his larger geared rollers. The rolls were originally intended to have deep grooves to roll the T-rings, but I got these laser cut in quadrants to be welded together, so the grooves were never machined.

The rolls exist as a CAD model so drawings are available.

Andrew

[Anonymous]

KWIL: Thanks, that three people saying it will be fine silver soldering LG2, so I'll stop worrying about it.

Ok, I understand about the drilling now, that's what I was going to do, except that I'll probably use a ballnose slot drill to get a nice smooth transition at the bend. This is what I want the elbows to look like:

I don't see how I can make them from solid without a lot of filing to get a nice smooth finish round the bend as it were! It should be simpler to silver solder two parts together? For scale the OD is 3/4".

Andrew

[JasonBModerator @jasonb]

Isn't that what you have a CNC machine for I've seen some very nice fittings CNC'd from solid.

I'll sketch out how I did the Fowler elbows which are similar as I did not do a straight forwards mitre joint.

J

[John Stevenson 1Participant @johnstevenson1]

So when are we going to get you over to the dark side then Jason ? 

 

[Edit ] Forgot the smiley.

Edited By John Stevenson on 28/12/2015 13:20:14

[JasonBModerator @jasonb]

Well if you have got a spare machine knocking about John, you owe me a favour

At least I will have the advantage over you of being able to draw the part I want to make

Edited By JasonB on 28/12/2015 13:26:47

[John Stevenson 1Participant @johnstevenson1]

Ouch, that was below the belt.

 

Email sent.

Edited By John Stevenson on 28/12/2015 13:31:28

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