Author Topic: Hick Crank Overhead engine  (Read 14237 times)

Offline AVTUR

  • Full Member
  • ****
  • Posts: 244
  • West of England
Re: Hick Crank Overhead engine
« Reply #15 on: September 10, 2019, 07:07:41 PM »
The decorative feature on the top of the standards is a poor example of the casters' skills. It was one reason why I put the castings aside a few years ago.

I am not sure how, or even if, I am going to correct them. They have already been sharpened up with a file during fettling.

AVTUR
There is no such thing as a stupid question.

Offline Jasonb

  • Full Member
  • *****
  • Posts: 9466
  • Surrey, UK
Re: Hick Crank Overhead engine
« Reply #16 on: September 10, 2019, 07:45:32 PM »
I think I would mill off the raised vertical details and then go a bit deeper over the whole area. Then machine up a couple of flat strip to fit that can have a series of grooves cut into them and stick them in place with JBWeld. This gives nice square ends unlike the ball nosed cutter option.

Offline Johnmcc69

  • Full Member
  • ****
  • Posts: 792
  • Erie Pa., USA
Re: Hick Crank Overhead engine
« Reply #17 on: September 10, 2019, 07:48:46 PM »
That's a shame. Cool little feature.
 I like Jason's idea about using a ball end mill there.

 Good progress though!  :ThumbsUp:

 John

Offline AVTUR

  • Full Member
  • ****
  • Posts: 244
  • West of England
Re: Hick Crank Overhead engine
« Reply #18 on: September 16, 2019, 12:40:05 PM »
After getting them shot blasted I have been giving the standards much thought. So much so that I put pen to paper (fingers to keyboard) so that I do not confuse myself. In the manner of a student to puts the longest, most complex equations into his/her presentation of work to hide the fact that he has done nothing, my ramblings are as follows:

The front standard has two bosses for the piston rod guide.

Function
1.   To hold the crankshaft assembly
2.   To locate the piston rod by means of a guide block
3.   To hold the governor spindle bracket
4.   To hold the rocker shaft

Fit: Datum 1 - Horizontal plane provided by base of standard, Datum 2 - Vertical plane provided by face of rear edging on standard, Datum 3 - Vertical plane of symmetry. These planes are orthogonal.
1.   The height from base to plummer block face must be 5.125” ± ?”. The faces must be flat and parallel.
2.   The shelf on the inner face of the standards must be flat for the governor spindle bracket mounting collars.
3.   The face of the piston rod guide bosses must be flat and square to the standard base.
4.   The face of the rocker shaft bearing pads must be flat and square to the standard base.
5.   Holes in bases and for plummer blocks must square or parallel to the datums.

Form is all important, looks count for everything. As far as possible both standards should be identical. I would like to have kept the finish as cast but the casting was so poor. Therefore I think they will be machined all over except for the large recessed surfaces which will remain as cast. I want to keep the height of the edging from the outside recessed surface constant if possible. The finished results may be shot blast again. The frieze at the top of the standards must be prominent. I do not intend to think about them for the moment but I like Jason’s suggestion.

Inspection showed that some dimensions are tight, importantly the height of the standards, while others allow quite a lot of room for machining. There are no critical undersize dimensions. However the rear standard is twisted with the bottom of the right leg forward of the left by about 0.030”.

Machining sequence will probably be as follows:
1.   Mount standard outer face downwards on milling table, using shims to account for the twist in necessary, and skim inside edging to provide Datum 2.
2.   Skim rear of base pads and top platform
3.   Face top and bottom of shelf for governor spindle bracket, rocker shaft bearing pads and top of base pads.
4.   Turn over and mount Datum 2 face against table (again using a suitable block of metal) and skim front of base pads and top platform.
5.   On front standard face piston rod bracket bosses.
6.   Clamp both standards together back to back using spacers and super glue if necessary.
7.   Mount vertically with feet upwards on an angle plate. [Think about Datum 3].

This is as far as I have got recording my thoughts. However it has given me the clarity to start work on the standards.


I have made some progress with the pump parts. The pump should be finished next week and I will give details.

I have also made the all important build stand.

AVTUR
There is no such thing as a stupid question.

Offline AVTUR

  • Full Member
  • ****
  • Posts: 244
  • West of England
Re: Hick Crank Overhead engine
« Reply #19 on: September 22, 2019, 06:53:53 PM »
It has been a week of puzzlement and progress.

I have decided on the machining sequence for the standards which as follows:
1.   Mount standard outer face downwards on milling table, using shims to account for the twist in necessary, and skim inside edging to provide Datum 2.
2.   Skim rear of base pads and top platform
3.   Turn over and mount Datum 2 face against table (using a suitable block of metal) and skim front of base pads and top platform.
4.   On front standard face piston rod bracket bosses.
5.   Clamp both standards together, front edging to front edging, using some thickness spacers, shims and super glue if necessary. Use two clamps that sit inside the castings. Make sure that the top platform and the inner faces of each standard coincide. Check distance from inside edging to inside edging which should be constant (±0.010”?).
6.   Mount assembly vertically with feet upwards on an angle plate using same thickness spacers and two sets of clamping bolts. Make sure, taking numerous measurements, that the mean line between inner faces is square to the base of the angle plate. This gives Datum 3.
7.   Skim just enough metal off the underside of the feet to give nice flat surface. This is Datum 1.
8.   Skim sides of base pads.
9.   Drill mounting holes in base pads.
10.   Remove from angle plate.
11.   Mount assembly vertically with feet downwards on the angle plate using same thickness spacers and two sets of clamping bolts. Make sure the feet are firmly against the milling table.
12.   Skim the plummer block faces to height.
13.   Drill the holes for the plummer block and governor spindle bracket holes.
14.   Remove from angle block and separate the two standards.
15.   Mount standard outer face downwards on milling table, using shims to account for the twist in necessary [as operation 1] with Datum 1 parallel to the intending cuts.
16.   Face top and bottom of shelf for governor spindle bracket, rocker shaft bearing pads and top of base pads.
17.   Drill and tap stud holes [see below] for the rocker shaft bearing pads.
18.   Finish.
19.   NOTE. The drilling of holes for the piston rod guide bracket will be left for the moment. Likewise the decorative machining.

Geoffrey King used screws and nuts to hold the bearing pads to the standards. I feel it would be nice not the break the cast surfaces of the standards so I intend to use studs.

I hope to start machining the standards this coming week.


I have finished the water pump except for tidying up and polishing. None of the parts present any real problems.

I reduced the size of the spanner hexagon on the screw caps from 2BA to 3BA because it looks nicer. Because they were held by the thread I used an old filing rest that was made many years ago for a smaller lathe. If I tried to produce the flats by milling the cap would have unscrewed from the fixture so scrapping my work. Even so the caps had to be kept in place by a small bar mounted in the tailstock when I did the filing (see attachment).

I do not like turning long small diameter rod so I decided to produce the collars on the pump columns by silver soldering short sleeve over a rod and then turning back the excess metal and solder. The collar/rod gap for the capillary flow of the solder would be fixed by centre punch marks on the rod.  I have this technique very successfully in the past with stainless steel rods and sleeves. It appeared to work this time with mild steel but when I turned off the excess the punch marks were very visible, they had not filled with solder (see attachment). Much puzzlement – I can only think that they too deep for capillary action to work (mild steel being softer than stainless) or the wetting by the solder of the steels is different. The second attempt, this time raising a large, clumsy bur on the ends of the collars worked

AVTUR
There is no such thing as a stupid question.

Offline AVTUR

  • Full Member
  • ****
  • Posts: 244
  • West of England
Re: Hick Crank Overhead engine
« Reply #20 on: September 29, 2019, 06:56:23 PM »
Slow but steady progress has been made.

I am machining the standards in the following stages:
1.   Mount standard outer face downwards on milling table, using shims to account for the twist in necessary, and skim inside edging to provide Datum 2. DONE.
2.   Skim rear of the feet and top platform. DONE – This was interesting since the clamping twisted the legs (see attached sketch) giving an odd rear face of the feet. Not a problem but a warning.
3.   Turnover and mount Datum 2 face against table (using a suitable block of metal) and skim front of base pads, DONE, and top platform, NOT DONE – I decided that this was not required.
4.   On front standard face piston rod bracket bosses. DONE.
5.   NEW STAGE – Front face against the table with suitable packing, correct the rear face of the feet. The finish was not good. The surface was slightly smeared which could suggest a blunt cutter, an end mill.
6.   Clamp both standards together, front edging to front edging, using some thickness spacers, shims and super glue if necessary. Use two clamps that sit inside the castings. Make sure that the top platform and the inner faces of each standard coincide. Check distance from inside edging to inside edging which should be constant (±0.010”?). CHANGE OF PLAN – I could not understand why I was clamping the two standards together. This is typical of carpentry and represents a lack of faith in repeatable machining. It struck me as being very cumbersome with too many clamps. The only possible gain would be the top platform heights might be the same. If you did them individually any difference in height of the crankshaft could be corrected when the plummer blocks were machined.
7.    Mount the standard vertically with feet upwards on an angle plate using same thickness spacers and two sets of clamping bolts. Make sure, taking numerous measurements, that the mean line between inner faces is square to the base of the angle plate. This gives Datum 3.DONE - for the rear standard [the front standard has yet to be machined]. I took the angles of the inner edges to set the datum (see attachment). Since I felt the part seemed very springy the top clamp was as close as possible to the feet.
8.   Skim just enough metal off the underside of the feet to give nice flat surface. This is Datum 1. DONE – Because of the above observations I did this slowly and carefully using a good sharp end mill, lowish cutter speed, low table feed speed and light cuts. It took time but I am happy with the result.
9.   Drill mounting holes in the feet. DONE – The hole in both legs comes out very close to the web of the structure. So more machining and a picture next week
10.   Skim sides of feet. DONE – I could not do the full face because the top of the angle plate was in the way. They will be finished off with a file.

The rear standard has been removed from the angle plate. The front standard and finishing the non-decorative machining on both is the next job. I would like to think that this will be done within the week, but next week is going to be busy.

AVTUR
There is no such thing as a stupid question.

Offline AVTUR

  • Full Member
  • ****
  • Posts: 244
  • West of England
Re: Hick Crank Overhead engine
« Reply #21 on: October 06, 2019, 06:05:30 PM »
I have had a busy week outside the workshop.

As for machining the standards, it has been a case of two steps forward and one step back.

I skimmed the feet of both standards flat to give a good Datum 1. After successfully drilling the fixing holes (4BA clearance) in the feet of the rear standard I lost Datum 3 on the front standard. The holes were in the wrong place. I plug them with phosphor-bronze rod held by quick setting epoxy glue and re-drilled the holes. I am not totally happy but I understand why Geoffrey King slotted the mounting bolt holes in the plummer blocks (at least he foresaw the difficulty in keeping a vertical datum through the crankshaft).

The next difficulty became obvious when the holes were drilled. They are far too close to the main web of the casting (see attachment, only one this week); yet more machining. I have abandoned my elaborate work plans since they have served their purpose with the remaining non-ornamental machining operations are relatively simple – facing the top platform, drilling the associated holes and producing clearances and flat surfaces for fixtures. I have started doing the latter on the front standard. The bosses for the piston rod guide bracket will be drilled during assembly.

On Friday I just sat at my bench, looked at these castings and just wondered; would it have been less hassle to have made them from bar stock? If so, would they be carved from a single lump of metal or fabricated?

It is a short write-up this week and next week is likely to be similar. Like anyone who has a good workshop others want to give you work. I only consider neighbours and good friends (family live miles away). A friend’s job has been on the shelf for a couple of months and I cannot ignore it any longer.

AVTUR
There is no such thing as a stupid question.

Offline Admiral_dk

  • Full Member
  • *****
  • Posts: 3752
  • Søften - Denmark
Re: Hick Crank Overhead engine
« Reply #22 on: October 06, 2019, 08:29:00 PM »
Well, progress is progress - even if it is not as fast as we could wish for ....

Offline AVTUR

  • Full Member
  • ****
  • Posts: 244
  • West of England
Re: Hick Crank Overhead engine
« Reply #23 on: October 14, 2019, 11:48:39 AM »
A week of progress and I have even done some work on the “foreigner”.

Facing the platform top of each standard and the shelf underneath was simple. The heights of the platform tops from the base are within 0.002” of each other and 0.007” to 0.009” below the drawing. The latter can easily be corrected, if required, when machining the plummer blocks. The holes for the governor spindle bracket, in the shelves were drilled. Geoffrey King used captured screws for the plummer blocks, I do not understand why. Therefore I am replacing them with 8BA studs; their holes were drilled and tapped. On inspection I found that these had half broken through on the underside into the side of the web (see attachment). No problem since I am using studs, but it would make the use of captive screws very difficult.

The webs at the feet have been machined back to give clearance for the 4BA fixing nuts. I can now just about get them in and possibly tighten them. Access for my smallest 4BA spanner is too cramped and the spanner is too long to swing between the two standards (see attachments). There are a number of options:
1.   Carve out more room – I am loathe to do this, everything will just get messier.
2.   Use 4BA nuts with 5BA flats – I know such screws are available but whether nuts are?
3.   Buy another 4BA spanner and modify it – Will probably have to do this anyway.
4.   Use 4BA screws instead of studs and tighten them from the underside of the bedplate. The tapped holes in the bedplate would have to be drilled out – This may present assembly difficulties.

Tomorrow I should finish the non-ornamental machining with the skimming and drilling of the mounting for the rocker spindle bearings. The tolerance on their location is tight so I have produced a simple datum plate that would have bolted onto the feet had the screws not fouled the webs (see attachment).

My shopping list for Friday’s quick visit to the Midlands show is rapidly increasing.

AVTUR
There is no such thing as a stupid question.

Offline AOG

  • Full Member
  • ****
  • Posts: 730
Re: Hick Crank Overhead engine
« Reply #24 on: October 14, 2019, 02:44:26 PM »
If you have a 4BA tap you can make nuts to of what ever size you need. If you don’t have a hex block you can use a pair of full size 4BA nuts to put in the facets or even go with square nuts..

Tony

Offline Jasonb

  • Full Member
  • *****
  • Posts: 9466
  • Surrey, UK
Re: Hick Crank Overhead engine
« Reply #25 on: October 14, 2019, 03:12:33 PM »
Easiest to drill out and tap some 5BA nuts with a 4BA tap

Offline AVTUR

  • Full Member
  • ****
  • Posts: 244
  • West of England
Re: Hick Crank Overhead engine
« Reply #26 on: October 15, 2019, 07:15:24 PM »
Tony and Jason – Many thanks for the suggestions.

I found I had a 4BA – 6BA spanner pressed out of steel plate. Such spanners are just asking to be modified. After quite a bit of careful filing I am now able to tighten all four nuts without having to do further work on the standards. The 6BA end has been cut off so that I can swing it between the standards.

AVTUR
There is no such thing as a stupid question.

Offline AVTUR

  • Full Member
  • ****
  • Posts: 244
  • West of England
Re: Hick Crank Overhead engine
« Reply #27 on: October 25, 2019, 01:14:51 PM »
This is really an aside and not a progress report.

Since starting the build of the model I have been trying find out something about the engine and company.

Hemingway Kits give a little bit of information on its web site:
The model is 1/12 scale of a 10NHP engine shown at the Great Exhibition in 1851. The original engine’s cylinder would have had a bore and stroke of 9” and 22.5” with a 90” diameter flywheel.
Hick, Hargreaves & Co. was formed in 1845 when John Hick, who had a foundry in Bolton, went into partnership with William Hargreaves.

Grace’s Guide (summary):
1845 – John Hick went into partnership with William Hargreaves at Bolton
1855 – Stopped build locomotives to concentrate on large marine engines
1866 – Were making engines using the American Corliss valve gear
1868 – John Hick retired
1889 – William Hargreaves died and the business became a limited company
1892 – Became a public limited company. By 1894 they had made over 1,100 Corliss engines of up to 2,000IHP.
1908 – Took out a licence to build Uniflow engines
1911 – Started making diesel engines
1918 – Were making high vacuum condensing plant
After 1945 – Diversified into electrical generation, food processing and oil refining
1968 – Acquired by the Electrical and Industrial Securities Ltd
2002 – Was a part of the BOC Group
The guide has some pictures of large marine and mill engines. Their entries are fully referenced and I intend to take a look at copies of The Engineer at Bristol Reference Library before Christmas.

The works records were deposited with the Bolton Library in 1980 and 1982. Although one of the largest collections they do not feature on the Bolton Library and Archives website (I feel  this says something about our present culture). The collection appears to be indexed at the top level, engine orders, drawings, correspondence etc, but no feature. Like the Bristol Reference Library, the documents are stored off site. I have been in difficult email contact with them for over two months. The archivist, who is part time, has not got a clue what I am looking for and I live 200 miles from Bolton. I think this will require a lot of emails and patience. However, fortunately, the records exist.

A progress report is following in the next few days.

AVTUR
There is no such thing as a stupid question.

Offline AVTUR

  • Full Member
  • ****
  • Posts: 244
  • West of England
Re: Hick Crank Overhead engine
« Reply #28 on: October 30, 2019, 08:10:47 PM »
I did not post a progress report last week since very little work was completed. I have now settled in to a work pattern where more than one item is being made (often two at the same time, one in the lathe and the other in the mill). In addition I have had a session of making tooling and fixtures such as filing buttons and a form tool.

The bearing pads on the Standards have been milled flat and the holes for the Rocker Shaft Bearing screws drilled and tapped. I managed to do the holes without breaking through the front skin of the Standards. I also found I had an 8BA bottom tap that actually cut to the bottom of the hole so all four holes now have a thread depth of about 1/8” (I was going to grind the tip of a bottom tap to achieve this but sometime in the dim and distant past... ).
I started on the Rocker Shaft Bearings as if they were glands – Mount a suitable length of bronze rod in the lathe, face end, turn back the diameter (which, if it was a gland, would engage in the cover) and drill and ream the main hole. Transfer to the mill to drill the fixing holes, using the main hole as datum, and shape the flange. Then return it to the lathe to part the item from the rod. Finally file the flange to shape. This was a disaster. First the bronze rod decided to attack the rather blunt lathe tool. After the tool was re-sharpened I made progress although the milling cutter had to fight. Strangely parting off was nice and easy. The bronze has a silvery colour so it could have been aluminium bronze which I have met before. On inspection the part was nothing like the drawing, I had lost control of the hole positions. Thinking about this I realised that on such a bearing the position of the shaft relative to the mounting holes is critical. The general shape is not important. Using a different rod of bronze, a phosphor-bronze I think, two good pads were made. These are now loosely fixed to the Standards with the Rocker Shaft between them.

After the success with the bearings the Footstep Bearing was made. The final filing to shape is awaiting some filing buttons (really waiting for a nice windless day to use the propane torch).

The Governor Spindle and Collar have been produced. The Spindle is a simple length of rod. I decided to increase the diameter of the collar from 3/16” to 1/4” since the 10BA x 1/16” grub screw worried me – 3/64” metal thickness struck me as being too thin. In the end fitting the grub screw was easy although I will have to modify another screw driver.

I am splitting the work into “heavy engineering” and “controls”. I have started on the Plummer Blocks and the Short Rocker which should be the subject of the next progress report. In addition more fixtures and tools will need to be made soon.

Finally my shopping trip to the Midlands show was generally successful except the only 5/16” diameter steel balls (for the governor) I could find were stainless. If anyone knows of a source of mild steel balls please let me know. Otherwise I will have to try drilling stainless balls (stainless may look out of place anyway).

AVTUR
There is no such thing as a stupid question.

Offline AVTUR

  • Full Member
  • ****
  • Posts: 244
  • West of England
Re: Hick Crank Overhead engine
« Reply #29 on: November 19, 2019, 07:13:54 PM »
This should have been posted ten days ago but various things and telephone calls prevented me from doing so before I went on a week’s holiday to the sea-side. To make amends I have attached a holiday postcard (I hope no one will be offended – it has nothing to do with models).

My worries about the stainless steel balls for the governor were groundless. I did what I should have done when I got them home from the Midland show – see if a file cuts one. Yes, it was not too hard. There was then the thought on how you held a ball. Mentally I designed a nice little chuck for the lathe before realising that a ball might be held in a simple collet chuck without it slipping when drilled. Again this worked so a 10BA hole was drilled and tapped in two balls without difficulty. It is nice to have an easy success.

The Small Lever has been finished. The arm and boss were silver soldered together some weeks ago. I took the opportunity to re-drill and face one end of the boss after drilling and tapping the governor balls. The other end of the boss was faced using a mandrel and super-glue to hold the part in the lathe. It was then filed to shape and a tapped hole with a small counter bore drilled in the boss for a 10BA x 1/16” grub screw.

The Plummer Blocks have been made. One casting, rather wide, was supplied which had blow holes in the base surface. The largest was about 1/8” deep. The other block was produced from a cast block of gun metal (I think this was supplied instead of an actual casting). Geoffrey King used square headed 9BA bolts to hold down the Caps. These were trapped by their heads in a groove machined in the base of the blocks. Thinking that this is unnecessarily complex I intend to use 9BA studs Loctited into the blocks. Making the blocks was simple enough but one had to ensure that the blow holes remained hidden and did not break into the side of the block.

I apologise for the heavy shadow on the progress attachment. The photograph was taken in a cold dark workshop.

My trip to the Bristol Reference Library to look at old copies of “The Engineer” was mostly successful. I will post something when I have had a good look at what I copied (the print is very small). I must also have a look at Julius de Waal's design for the engine. Both of these will be left until the next spell of cold weather.

AVTUR
« Last Edit: November 19, 2019, 07:19:16 PM by AVTUR »
There is no such thing as a stupid question.

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal