A Table Engine Tale

[Ramon]

This project, a Waller Table engine from circa 1880, began around 1998 when the original model, designed by Anthony Mount, was published in Engineering in Miniature.

It was decided to make it one third larger which would give a flywheel of 12" diameter and an overall height including plinth of just under 17".

It's all made from spare material - or should that read material going spare - obtained whilst I was still working. Apart from the flywheel, which had the rim milled from a flame cut blank and the spoke holes put in at work all other machining has been done at home. Work has been carried out in fit's and starts over this time - up until a couple of years ago it was just parts languishing in a box but since then it's been erected and slowly worked on at various stages. As such it's very much been an 'infil' project then but hopefully it won't be too long before it's up and running. Currently work is ongoing on the motion gear with the last week seeing some progress on the piston/conrod/big end parts. I don't have too many pics but here are a few that will give some idea of work to date

The base and entablature are machined from steel plate. The pads for the columns are separate. Turned from square stock they have spigots that locate holes in the base and are held in place with Loctite then the 'fillets' are applied using JB Weld epoxy steel to give a 'casting' effect. Likewise the hold down bolt pads. All edges are machined/filed at an angle in an attempt to simulate a draft angle.

The columns are straightforward turnings all the radii formed with form cutters made from ground flat stock.

The cylinder is a composite one with all parts made from a rather tough cast iron cut from a redundant power press baseplate.

The valve face was fixed to the cylinder using a couple of 8 BA caphead screws and plenty of JB Weld. This stuff has great strength and a high temperature resistance that will easily take dry steam though this engine will probably only ever run on air.

JB is a bit runny and slumps a bit so plenty has to be applied but once cleaned up after twenty four hours curing the effect is reasonable enough

I guess that will give an idea of it's early days - I'll post some more later if you would like and gradually bring it to date.

Hope this is of interest to someone

Regards for now - Ramon

 

[steamer]

Cool Ramon! I like it!

Keep it coming!

Dave

 

[tel]

Yes, beautiful work Ramon - keep the flow going!

 

[lazylathe]

Looks like it is going to be a great engine when completed!!

Love the use of JB Weld for the fillets, very original!'

Keep the pics coming as you go along!!

Andrew

 

[MachineTom]

Nice work, well thought out, a great piece for sure when complete, garage jewelry. Look at Devcon epoxy it has iron dust in it, plenty thick compared to JB weld, can be milled and tapped.

 

[Ramon]

Hi guy's, thanks for the kind comments.

I have used Devcon Epoxy Steel Tom, you're quite right it is much thicker and is infact what I used on the flywheel spokes and hub. These areas are as yet unfinished hence the rather rough look. JB Weld, which can also be machined, has a slight advantage in having a higher temperature resistance but having said that this will only ever get run on air. (It's also a lot less expensive!)

The pics of the crankshaft outrigger pedestal bearing show the 'test piece' to see if it would give a reasonable impression of a casting. I was quite pleased with the result and am sure that once painted the effect overall will be convincing enough

The base and pedestal are cast iron and the bolt pads are steel

This is the initial 'gluing up' - perhaps that might be better phrased as the initial bonding - the base is held by two c'sink screws

The finished item and the bearing caps made in the same fashion. The bearing is a split one but is unsoldered at this stage

I've found this simple 'self pressurising' clamp made from a piece of 10SWG (1/8) piano wire to be the ideal thing when soldering the two halves together

The crank web was milled from solid rather than adding the small web by soldering.

The milling was done on the rotary table after drilling and reaming the two holes for shaft and pin. The part is not just held by one clamp BTW - which is a definite 'no no' - but is located on a pin in the sub plate.

After finishing the web was Loctited and cross pinned to the shaft and the crankpin done likewise. The flywheel was found, at this stage, to have a slight wobble so it, being too big to swing in the Myford, was set up on the mill and the bore enlarged. A keywayed sleeve located by two grub screws fits over the shaft which, after the valve eccentric position has been finalised will also be Loctited.

About this time last year after eventually erecting the box of bits it was exhibited as work in progress at a local show. After that event I spent about a month on it drilling and tapping most of the holes and finishing off the port face and the steam chest parts and finally making the cross head standards to bring it to the stage as shown at the start of the thread. The standards are steel with the guides made from cast iron, let in and fixed with JBW. The slots were milled after bonding and the lower faces then brought square to the slots.

The steam inlet boss was silver soldered to the steam chest and the steam exhaust manifold though threaded was JB'd to make it a permanent part of the steam chest.

Another year and another show and a decision to try to at least have it running for next year has seen some more work in the last few days so the next 'instalment' I guess really will be 'work in progress' Tomorrow - if thing's go right I should have the piston coupled up to the big end and something moving at last if only by hand power ;D

Regards - Ramon

 

[pete]

Ramon,
That's a huge amount of very well done work. Your calculator must be getting a real work out. Anthony Mount has the rare ability to pick very nice looking, unusual engines, and also work out and design all the details to end up with a functional engine. Your bar stock parts will be hard to tell from the actual castings other than they will look a lot better. IMO, That's going to be a really beautiful engine when it's finished.

Pete

 

[Brian Rupnow]

Beautiful "Work in progress".---Brian

 

[SBWHART]

Great work Ramon

Stew

 

[steamer]

Looks great Ramon. Castings are sometimes more of a pain to deal with than bar stock.

The setting up of the cylinders on my launch engine took a while and involved lots of lead shims and wedges to get the first cut...got better after that....but was a chore.
Dave

 

[GWRdriver]

I really do love to see projects done this way. It takes time and effort and bother but the results are worth it IMHO . . . this is my kind of model engineering. Well done so far!

 

[danstir]

Great job and some different techniques that I can add to my "maybe this will work" list.

 

[peatoluser]

Great project to follow. I like your piano wire clamp. Another technique to add to the armoury.
there's always something to learn on this forum. thanks for posting

peter

 

[Ramon]

Hi guys, thanks for all your kind comments - it's nice to hear that some feel that there is something worth bearing in mind for their future use too.

Regarding the build up of this engine let me say that whilst I have no hang ups about spending money on my hobbies (and I certainly have no desire of appearing to be controversial here) sometimes I do question the 'value' of some castings, their cost seemingly out of all proportion to their size and complexity and in many case their actual 'need' to be superfluous. In most cases I'm convinced, and I'm sure many will feel likewise, that with some considered thought, a careful bit of machining and the help of something like the JB Weld most can be replaced convincingly to a reasonable degree not only at a considerable saving but to a high degree of satisfaction to boot.

Following on from the previous post my best laid plans began to go awry when my wife felt my interests would be better served on a shopping trip to Tescos than in the workshop I tried to convince her otherwise but you know how it is : .... It seemed to go downhill from that point but at last I'm pleased to tell the piston is moving up and down in sequence with the big end

Here's some pics of the progress

The 27.0mm bore was honed using a three stone brake hone to smooth out the machining marks to leave a uniform 'scratched' surface

The piston is .05mm down on the bore and the packing is square section PTFE yarn. On previous engines I have found this to give an excellent seal but with very low friction - certainly if the engine is only ever run for display purposes and with a very long working life. The groove for the packing is .05 wider than the nominal section and the depth .05 less. (section in this case is 3/16" square)

First job was to make some radius forming cutters for the various 'ball ended' sections. These were made from Gauge Plate (Ground Flat Stock) (GFS from now on). The very slight top rake was milled on the angle set by eye but about 2-3 degreees and the radius milled in by an appropriate sized end mill plunge cut downwards moving inwards .5mm at a time to ensure a good finish. Side rake was milled and backing off on the sides done by file. Heated to a good bright red they were quenched in oil and left un-tempered. The only 'sharpening' carried out was to run a flat stone across the top rake. I have no T&C grinder just a couple of offhands 8" and 5"

This is the lower cross beam that spaces the con rods in the initial stages. The three cross holes have been drilled in situ on the lathe using a cross slide drilling attachment.

Forming the central boss using one of the cutters. The front edges of each side of the cutter is set at centre height which because of the top rake brings the outer radius slightly below. Obviously a true ball is not formed but it's close enough for the task in hand

The tapers were cut next to be followed by forming the ball ends (no pic of that op) but this is how they looked before final parting off

Parted off and ready for finishing off

They were held in a split collet quickly turnd from a scrap of ali the small end resting in a smaller hole 'socket' and the part gripped by the cental ball. The radius cutter was brought gently in to play to finish the ends.

I have just hit the post button instead of preview : so perhaps abit more later tonight

Hope this is of interest
Regards Ramon

 

[maverick]

I too am a fan of form tools. It may seem like extra work but once the tool is finished the parts appear
almost like magic. The part you turned has a clean sharp appearance that will complement the rest
of a very nice engine. Great job on a fantastic build.

Regards,
Mike

 

[Ramon]

Here's a bit more of an update but this time I'll try not to hit the post button too soon

I decided to make the coupling rods composite rather than try to turn the whole thing from solid. It was much easier this way and a lot less swarf to be made. The little ends were turned using another radius tool to shape the ends then held in the dividing head on the mill to mill the flats and the cutouts. It was then returned to the lathe for the spigot to be turned (4.0mm) and parted off.

The bearings were split and soldered then set on a spigot for milling the rebate. This was the first time I had used this method and wasn't quite ready for the central raised taper caused by the cutting angle on the bottom of the slotting drill to be so prominent. It was quickly solved by cutting the radius in a series of steps one turn at a time from one side then reversing but making the first move a half turn then full turns to double up the number of flats. The image is not very good but should give an idea

The lip on one side was milled off to the centre line then it was rotated 5 degrees for facing to length and applying the taper.

The rods were turned from 8.0mm stock down to 6.5mm and each end tapered by two cuts at 1 degree then a half degree. By leaving the central portion flat it could be turned round in the collet chuck for the other end. The bellied shape was put in using a very smooth file and emery finishing off with wet and dry with paraffin (kerosene) as a lube followed by a final rub with a Garryflex abrasive block.

The ends were Loctited in using 638 high strength retainer and a single pin put in just to be sure. I took several pics of this op in case anyone is interested in making pinning invisible - well as near as you can - but heres the result - the R/H one is after the initial filing and the L/H after emerying. If you'd like a fuller description let me know.

Heres the cross beam and big end after pinning too. This has been pinned in the centre of the boss. The pin doesn't go right through, just into the far wall of the other side of the hole.

Finally there a set of parts to fit

Which has brought the engine to this state

Today has been spent making studs for the valve chest so tomorrow work begins on the valve gear. The new compressor has arrived though so time needs to be spent on plumbing that in which will interupt the flow abit.

Back a bit later then, in the meantime I hope I'm not overdoing this - if I am please give me a shove in the right direction, I won't be offended

Regards - Ramon.

 

[user 4756]

Hi Ramon,

Absolutely fantastic as always! :bow: :bow: :bow:

Please don't ask if anything you produce is 'of interest', we all hang on your every word! Thm: Thm:

Ideas spread from your pictures and descriptions!

I use old files for form tools, held against the handrest like using a woodchisel. Nothing as big as this though but similar to the form around the cylinder. Just grind the end level with a bit of rake then grind out the shape from each front corner which gives a left and a right hand tool. For those who want to try it, for god's sake remember to put a handle on the file, the tang will take no prisoners if it catches. Keep a low speed and good pressure on the workpiece; cuts beautifully!

Looking forward to the next installment!

(Miranda says if you are too slow we will come and visit! :big

PS for everybody else. That's worse than the Jehovah's Witnesses! :big: *discussion* *discussion* *discussion* *discussion* *discussion* *discussion*

Andy

 

[pete]

Ramon,
If anything, Your underposting in my opinion. High quality work speaks for itself and I can look at yours all day.

Pete

 

[peatoluser]

Yes, I'd certainly like a fuller description of how you 'invisibly' pin, as it were. mine nearly always seem to be visible, especially when I don't want them to.
thanks in advance

peter

 

[bearcar1]

Ramon, that is absolutely, without a doubt, some beautiful work. Please do not think for a moment that you are over-posting. Lots of pictures and a running editorial is what makes things interesting. I enjoy fine work as much as the next guy, but there is just something lacking when someone posts one single picture and basically says "here's what I built". However, actually reading about the trials and tribulations of what a builder had to go through in order to reach the final destination is, shall we say, priceless. You have certainly given me some new, ways of doing things, to think about. Thank you.

BC1
Jim