# Mill Engine



## deeferdog (Jun 19, 2019)

I have started work on a new project, a horizontal steam engine designed by Mr Harold E Benson. The plans are free, metric and have been well drawn by J.A.M. DeWaal of New Zealand. Here is the link  http://www.vapeuretmodelesavapeur.com/telechargements4/.
 The engine is quite large, nearly 700mm in length. This will be a bit of a relief over the last engine as it required a lot of M2 tapping and I felt more like a watchmaker than a hacker machinist. These plans call for a twin flywheel arrangement but mine will have to make do with one as that is all I have at the moment and funds are tight, plus I'm in the doghouse for a bit of an overspend on tooling so it behooves me to keep a low fiscal profile  and let the storm clouds blow over.
My cast iron flywheel is quite a bit different from the one in the drawings, in a previous life it was probably a flat belt drive pulley in a shearing shed, I got it for a few dollars from an Op shop a while back. It just fitted into my lathe, I made a stub axle and press fitted it into the hub. This was later drilled and bored to the correct diameter and machined off in the mill. Most of the turning was done with a boring bar turned upside down and the lathe run in reverse as that was the only way I could get at it. I expected that the cast would be diamond hard because of the age, in truth it turned like butter silk and was an absolute joy except for the MESS!  In the end it turned out quite well and I was pleased with the result. The pics tell the story better than I can.  More later. Cheers, Peter.


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## deeferdog (Jun 27, 2019)

Next to the crankshaft. These are not my favourite thing to make, over the years I've tried various methods, all of which ended up with a case of the wobbles that required a bit of  discipline to bring into line. The plans called for this one to be fabricated, Loctited and pinned but if I had had the material on hand I would have preferred to cut it from solid as I have had more success that way than any other. One thing for sure, I was not going to silver solder it together. To those who can do it that way, I salute you. My attempt was so distorted as to be unusable. To make the cranks I had a small piece of 25 x 25 mild steel, not the preferred material but this is on a tight budget so it would have to do, the shafts would be cut from 15mm round bar. For once, everything went reasonably well, after press fit assembly with Loctite and left to cure overnight, I pinned the shafts and cranks using 4mm nails press fitted in with Loctite and machined off. The final result was about 200 microns off and some persuasion was needed to improve on that. So far, so good.  Next the main bearings. Cheers, Peter


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## deeferdog (Jul 2, 2019)

Before going on to make the main bearings for the crankshaft, I decided to construct the base of the model. I used a piece of 6mm aluminium plate 767mm x 260mm, a seriously large piece of metal to handle in my small shed. There is only limited work to be done on it, mainly the cutting out of the sump for the crank to turn in. The cutting was done using a 16mm ruffer milling cutter and proved fairly easy to do but it took a long time to set up in the machine. The next problem was the edge of the plate, this needed to be 20mm.  Firstly I tried epoxying 20mm x 6mm bar to the sheet, total failure. Next brilliant idea was to fasten through with 3mm countersunk screws. This looked dreadful so in the end I used 20mm x 20mm x6mm angle and bolted this to the plate and radiused the edge using a router trimmer and CT wood bit. Much filling with bog and sanding produced  a reasonable base in the end and I think it will look OK when painted, it was a lot more messing around than I anticipated,

















 furthermore, because the piece of aluminium had been guillotined from plate it has a slight curve across its width, I'm sure that will come to haunt me in the coming weeks. The plans call for the base to be elevated on a timber stand. I made this from some Spotted Gum hardwood flooring that I had lying around. The two pieces were dowelled together but not glued, then screwed down onto two cross pieces forming the feet. Four coats of varnish and this was finished. The supporting posts in the plans are simply round pipe but I think that they can be made to look a bit better than this, I'll have a think about it and show the results in the next post, Cheers, Peter.


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## deeferdog (Jul 4, 2019)

To make the posts for the base, I decided that because the Mill engine was from the Victorian era I would try to add that flavour to the model. I cut six pieces of  20 x 20 x 1.6 mm square tube to length and set up my mill. I firstly wanted to put some stopped chamfers on the posts and this is quite easy on my machine as I have adjustable electric stops added to the X axis of the table. Once the distance is set, each post is placed in the vice and the 45 degree radius bit traversed back and forth on each edge. Next I decided to "vein" the posts as this adds a lot of charm, I think so anyway. The process is similar to stopped chamfering but this time using a 3 mm bull nose bit. Two veins were added to each side of each post, this sounds quite time consuming, in fact it is very quick if electric stops are used on the traverse, additionally I have used a dynamic braking circuit on the X axis DC motor, this ensures that the motor stops almost instantly when the power is removed and ensures good accuracy. When the posts were finished, the most laborious part was the cleaning up and polishing. I used 600 grit wet and dry paper on the surface plate with a spray of kerosene and oil to remove any surface scratches, then polish on the wheel. They are a bugger of a thing to hold but I got the job done in the end. I think they look quite good. In the next post I will show the making of the brass and teak bases for the posts and the fitting to the base. Cheers, Peter


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## a41capt (Jul 4, 2019)

This looks very interesting. I’ll have to try the reverse trick if I’m forced to use my Enco 9” lathe in the future!

I like your solution to the standoff posts as well. Very nice!

As for silver soldering, if you don’t need high temperature resistance, buy the lower temp silver solder instead. When higher operating temps are expected, just make sure and use plenty of the correct flux on the cleanest surfaces you can produce. If possible, a clearance of .001” to .002” will allow a better flow, at least that’s what I was taught in high pressure gas school in the Navy, and relieving a channel to place a piece of solder between the pieces to be joined ensures an even flow after temperature is achieved.

Looks like a nice project, and I'll be following along!

John


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## deeferdog (Jul 5, 2019)

Thanks for the comments John. To finish the supporting posts I thought they needed a plinth to stand on. I cut some 3 mm brass bar into squares, milled the edges and drilled a 8 mm hole in the centre. I ran around each one with a radius mill then polished them. Squares of Teak timber the same size but 10 mm thick were cut to place under the brass plate. I used 8 mm threaded rod for the bolts going through the posts. It is easier to see the results from the pictures than me describe the assembly. The top nuts on the engine bed plate will be changed for brass at a later date. The whole became very rigid and strong when the nuts were tightened which it will need to as I am starting to realize that this will be a very heavy model when finished. I'm sorry the photos are a bit out of sequence with the text, I am having all sorts of difficulties with this site that has never happened before, possibly it is because I'm getting older but not wiser. More later, Cheers, Peter.


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## a41capt (Jul 5, 2019)

Wow, very decorative! This’ll be a beautiful piece when you’re done Peter.

I’m still a newbie after about 20 years with my equipment, and you’d think I’d be better at prettying things up with my years of woodworking and cabinetry. The plain and simple truth of the matter is that I build my metal projects for function more than beauty and I can’t quite break that habit. I’m just starting on building Henry Ford’s “Kitchen Sink” engine, and I can’t think of a more cosmetically ugly engine. I guess I just love the beauty of the engineering!

John W


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## retailer (Jul 6, 2019)

Good to see the crank did not cause you any grief, it looks like a reasonable sized engine which will need a reasonable sized boiler or is it going to run on compressed air.


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## deeferdog (Jul 6, 2019)

Hi retailer, this engine has a 76 mm piston (three inch) and a stroke of 100 mm (four inches), I haven't done any calculations but I think it would be a real steam hog and certainly too big for my tiny air compressor. My immediate aim is just to finish it, then it will probably sit alongside the beam engine (pictured) I made a while back. It is also a very large model, so I'm hoping they will complement each other. Historically they were two very important styles of steam engine during the Industrial Revolution.


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## retailer (Jul 6, 2019)

That beam engine looks fabulous it must be very satisfying to complete something to that standard.


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## deeferdog (Jul 6, 2019)

Thanks retailer, I really appreciate your comments. I made the Beam engine not long after starting out with this hobby and I sure learned a lot when I was building it. I got a lot of help from the members of this forum which is why it is my favourite. I put up quite a few posts during the build and if you would like to know more, you can find them here. https://www.homemodelenginemachinist.com/threads/bolton-12-beam-engine-from-scratch.26462/   Cheers, Peter


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## deeferdog (Jul 8, 2019)

Now that the base and engine bed has been sorted I could turn my attention to the main crankshaft bearings. There are three of these, one either side of the crank and one near the flywheel. My model will only have one flywheel. The bearing housings were cut from 25 mm thick aluminium bar to a finished size of 75 x 50 mm. I glued all three blocks together with super glue and machined, drilled and reamed all as one piece, then broke them apart.  The bushes I made  from brass and these were press fitted with Loctite into the bearing blocks, then an oil gallery drilled down from the top of the block through the bearing. These will be fitted with little brass spring ball bearing feeders after painting. The underside of the blocks were drilled and tapped with two 10 mm holes each and then the whole assembly, bearings and crankshaft, was aligned and bolted to the engine bed. I attached the flywheel and would like to report that everything spun like a delicately balanced gyroscope, but of course it didn't. Not really tight but certainly stiff, I connected a battery drill to the other end of the shaft and after 20 minutes or so, with lots of oil, everything freed up and I was reasonably pleased. If I was to do these again I would bore the bearing holes rather than drilling and reaming, I think the result would have been better. Here are the pics, hope you enjoy. Cheers, Peter





View attachment 110116
View attachment 110116


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## deeferdog (Jul 9, 2019)

The big end journal bearing is the split type. I made the bushing from brass and press fitted it into a 25 x 25 block of aluminium which was then machined to size. A couple of saw cuts with the slitting saw on the mill and the piece was made. I drilled an oil gallery through the cap and bearing in the same fashion as the main bearings.and 











 will shim the bearing to the correct tolerance on the final assembly of the engine. The plans call for 14 mm bar fro the connecting rod, but as I only had 12 mm on hand this would have to do. I threaded this M12 into the bearing block and left the rod slightly longer than called for, this will be cut to the correct length when the crosshead yoke is fitted to the other end. Polished the bearing and fitted. Looked pretty good, starting to get a feel for the model now and think that it might possibly be one that I finish. Cheers, Peter


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## deeferdog (Jul 14, 2019)

The little end of the connecting rod connects to the crosshead through the crosshead yoke. The little end is a block of aluminium with a bearing. It is attached to the connecting rod by press fitting into a 12 mm hole and pinning. Two things were important during the making of this, firstly that the distance between the main bearing journal and the crosshead pin be accurately established and that the crosshead bearing and the main bearing be aligned in the same plane before drilling the little end pin. The pictures explain it better.


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## deeferdog (Jul 15, 2019)

The design of the crosshead on the plans, I thought it looked a bit ordinary and could do with some improvement. I kept the basic idea of the crosshead slide, made out of brass, but changed the style of the supporting pillars and slides. The finished result looked terrible, I sure hadn't improved anything looks wise and I wasn't convinced it was going to work all that well. I bit the bullet and started again. I decided that the crosshead slide should be steel with proper bearings and these would slide on 12 mm bright steel bars, this being the best that I had lying around. The supports for the slides I made from 12 mm aluminium bar with the end being larger and bored to later support the stuffing gland end of the cylinder. This time everything came together, at least to my mind, and with things in place I thought it looked quite good. The bearings were a little stiff on the slides and I think this is due to the overall alignment and height of the various parts. I will wait until the cylinder and the piston rod have all been made before checking and shimming as necessary. I hope these pictures compliment the text and things are made a little clearer, Cheers, Peter.


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## deeferdog (Jul 16, 2019)

Well, onward and upward as they say. This model is starting to occupy nearly all my free time and mutterings can be heard about leaking shower taps and a retaining wall that needs repair. Possibly tomorrow, more important things first. The cylinder for this engine has a 76 mm bore and the plans suggest using steel pipe, however 76 mm ID x 88.9 mm OD is a standard size in aluminium round tube and by using this I would not need to bore the cylinder, something I was not looking forward to, it would really push the limits of my machines. The internal walls of the tube are very smooth and seamless. The roundness I just had to accept, when the piston is made I will lap as necessary. Setting the over 160 mm long cylinder up in my lathe took quite a while as I do not have  any means of supporting it. Taking extremely light cuts I managed to machine the end to size but I set it up in the mill to square off the ends and bring the overall length to specifications. The milling of the inlet and outlet ports was straight forward, all in all there wasn't a whole lot of work required. The cylinder end was a different matter. Made from a chunk of 100 mm round bar it took all morning of boring and turning with endless checking of the measurements. This item is a press fit and I almost never seem to get these quite right, either too sloppy or the opposite. This time I left the cylinder 0.02 mm oversize, popped it in the freezer for 30 minutes, added Loctite to the end cap, brought the two together under the press, and gently pressed away. Perfect. So, things are starting to take shape. Ratting around in the junk box has revealed a piece of bronze cored bar that might be good for the piston, we'll see. Turning a blind eye to the retaining wall, I went inside for a drink. Cheers, Peter


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## deeferdog (Jul 19, 2019)

Time to work on the opposite end of the cylinder, two flanges need to be constructed, one bored and press fitted to the cylinder body, the other becomes the head of the steam engine. I cut two pieces of aluminium, bonded them together with super glue and marked out the bore hole. Using this centre I then marked the radius of the top and cut away the waste on the band saw. Next I drilled a 10 mm hole through the centre of both and using this hole as a pivot, carved the radius slowly against a spinning 12 mm long series end mill. I saw this technique on Youtube some time back and it works well, just remember to work against the rotation of the mill. The two flanges were still bonded when the holes were drilled for the head bolts but then separated so that one was tapped for M12 and the other enlarged to 12.5 mm. Both received a quick facing skim, then the flange with the tapped holes was bored to be a press fit on the cylinder using Loctite. Everything went well, so now the cylinder is complete with only the stuffing box at the other end to make. Photo's, as always will help with the explanation. If anybody is reading these posts, please feel free to add any comments. Cheers, Peter.


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## johnmcc69 (Jul 19, 2019)

Looking good!

 John


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## Cogsy (Jul 20, 2019)

You're a braver man than me to do that radius like that! I've done similar to shape conrods and small bits, generally with some hard stops so it can't completely spin the part if it grabs, and I've had it grab on occasion. Maybe it's easier to control with a larger part but I'm just too scared to try it. Nice job on it though - turned out great.


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## a41capt (Jul 20, 2019)

I too am impressed with you pulling off that radius cut on the mill! I may have to give that a try, but like Cogsy says, with some type of a hard stop so it doesn’t get away from me.

I’m really liking what I’m seeing on this engine. I especially like the treatment on the con rod big end!

Looking good engine, and being BIG I’m doubly impressed!!!

John W


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## John Antliff (Jul 20, 2019)

As long as you do the radiusing using conventional milling and NOT CLIMB milling you should be able to control the job without any grab taking place.   Do it the wrong way and you will result in driving the  job around the pivot with most likely a broken end mill and seriously dented pride!  The hole and pivot need to be intimate i.e. no slack.


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## deeferdog (Jul 21, 2019)

I have to admit that when I did the radiusing I didn't think too much about it grabbing. I worked carefully, conventionally milling and only took small cuts. After reading what Cogsy has said about his experiences I can sure see the sense in setting up stops. I guess the similarity is holding a piece of steel in the drill press and wondering if its going to grab. It's only after it has, and nearly broken your hand, that you start to think that clampling it first might have been a good idea. Thanks for all the comments, Cheers, Peter


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## deeferdog (Jul 22, 2019)

On to the stuffing box which, as everyone knows, is a very old fashioned device for preventing steam pressure from escaping out of the cylinder around the piston rod. All the machining was brass, a metal that is lovely to turn but terrible to clean up after, the chips get right into the guts of the lathe! Enough whinging, fairly straight forward job, slightly changed the dimensions to suit what stock I had on hand. As an example , the plans call for a finished size of 52 mm and I only had a piece of 50 mm round bar so 50 mm finished it became. It doesn't fit into anything so no problems. The stuffing box cap was made from the same bar and the the six holes drilled using the RT. The box itself is attached to the cylinder with four screws from the inside, everything secured with Loctite.  Finished off the day by replacing the washers in the shower taps even though I know they will only last a couple of months as the tap seats are absolutely shot, what a bugger of a job that is going to be to fix. Advance  to the piston tomorrow. Cheers, Peter.


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## Cogsy (Jul 23, 2019)

deeferdog said:


> Finished off the day by replacing the washers in the shower taps even though I know they will only last a couple of months as the tap seats are absolutely shot, what a bugger of a job that is going to be to fix.



Peter, if the taps seats are too chopped up to use one of those cheap seat recutters you can buy from Bunnings, and they're set into the wall and hard to change, there is another easy solution. About 10 years ago I went to a plumbing supplier (Reece's Plumbing over here in WA) and bought a kit to repair damaged seats. It's basically a tool which screws into where the tap normally does, and it bores the throat of the seat to the correct size, then taps the bore of the seat. You then remove the tool and screw in one of the supplied stainless steel seats into the new thread and reinstall your tap with a new washer. From memory the kit cost me around $60-$70 but it's far cheaper, and simpler, than masonry work. 

Engine is looking great by the way!


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## deeferdog (Jul 23, 2019)

Thanks Cogsy. I've been warned that the re-cutters sold by Bunnings can do more damage than good. I didn't realize there was a better quality alternative available so I'll pay Reece a visit, possibly after I do the retaining wall. Does it ever end? Thanks for your interest, Cheers, Peter


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## deeferdog (Jul 23, 2019)

At last the piston, and at 76 mm diameter it was going to be a bit of a beast, I had a piece of cored bronze that was 80 mm so I decided to use that and put an aluminium centre in. The bronze was beautiful to turn and the centre was made as a press fit and once  again pushed in with good old Loctite 263. Possibly the purists will be aghast at this mix in metals for the piston due to the dissimilar expansion rates but this will be basically a static model that will only ever be run on air so I think it will be OK. It's all I've got anyway. I cut a groove for an O ring, bored and tapped the centre M12 and threaded a piece of 12mm bright bar for the connecting rod. This too was Loctited into the thread in the piston. For once I got a lovely fit, slides up and down the cylinder and makes puff puff sounds, I think it will run OK without an O ring should I decide to go that way, we'll see. Some pictures and then on to the valve chest. Cheers, Peter.


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## retailer (Jul 24, 2019)

Looks like it is full steam ahead for you on this one - it's coming together nicely.

On the subject of the bathroom taps - if you go the route of tap seat inserts then do not use the nylon washers supplied with the kit for the hot tap, hot water flowing through the tap causes the washer to soften and compress and it will soon start to leak, use a fibre washer instead.


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## deeferdog (Jul 25, 2019)

Thanks retailer, I'm rapidly becoming an expert in tap washers, the variety is mind boggling, all of which have proven useless. So, on to things at which I have had more success, steam engines. As I mentioned in the previous post, the steam chest must now be addressed. This part of the model is the most complex as the chest is comprised of six separate parts. The first, the gallery block fits against the cylinder over the upper and lower inlet holes and becomes the manifold to distribute the incoming and exhausting steam. I cut the block from a larger piece of aluminium with the slitter and machined the various faces as per the drawings. The holes were drilled mostly in the correct places, mistakes were made but were able to be corrected. The two end holes that are necessary for the inlets to be connected, simply plugged and machined off rather than tapping and fitting a screwed plug, this made the whole thing a bit simpler. Probably I spent more time figuring out the drawings than in the making of the piece. The plans are good and well drawn but some of the views are confusing, however I am easily confused. Pictures as always to assist in understanding this convoluted text, to those who are still with me on this build I not only thank you but also salute your endurance. Finish off the chest in my next post, Cheers, Peter.


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## deeferdog (Jul 28, 2019)

The completion of the steam chest was reasonably straightforward necessitating the making of three sides and the top and bottom. Some close fitting is required here and hand finishing with a file was needed to make the parts look the part. A broken tap didn't help, M5 and it broke on withdrawal, always the worst case in my opinion. I messed around with it in the usual fashion in the forlorn hope that I might be able to extract the stump but this ain't the movies so in the end I just ground it flat and left it be. The lid will feature a fake screw in that location. (That should  trigger a bit of muttering.) When it was all finished and fitted it looked remarkably close to what the designer had drawn, which is not always the case with my work. Pictures submitted as usual. I am looking next at the slide valve made from a solid lump of brass. The designer must have a lot more money than I have so that will have to be changed. I'll show how in the next post, Cheers, Peter.


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## johnmcc69 (Jul 28, 2019)

I'd say it looks like things are moving right along peter, nice work.

 John


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## deeferdog (Jul 29, 2019)

Thanks for the comment John. On to the vexed topic of the slide valve. I say vexed because the finished external dimensions of this piece are 52 x 32 x 30 mm which is a fair lump of brass and where I live, brass is difficult to buy and expensive plus I promised that this engine would be made largely with what I had on hand. I decided to make the slide from aluminium and fit a brass "shoe" on the face that slides against the gallery block. I fastened the shoe to the valve using four bronze dowels, pressed and Loctited into the aluminium block, then faced off. The dowels were small pieces nipped from the end of a bronze welding rod. The whole of the slide was then finished as per the drawings. The valve stuffing box I made as a smaller version of the cylinder one which was a departure from the plans but I thought it looked better, and I used 8 mm bright bar for the slide valve connecting rod. Everything came together in various levels of harmony when I did a test assembly. Good. Later I will do the permanent fitting of the valve chest to the cylinder and make any adjustments as necessary. My adjusting tool of choice is a hammer. More pics, have a good day to all who are reading this, Cheers, Peter.


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## champ2run (Jul 30, 2019)

I am thoroughly enjoying your skill and ingenuity. Impressive to say the least. Looking forward to the run. Ted.


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## deeferdog (Jul 31, 2019)

Thanks for the praise Ted, thoroughly undeserved but I love it anyway. The engine by now had passed the half way point and some decisions need to be made concerning the painting, even though this will take place when the model is finished. Some parts can be described as a sub assembly and painted as such without being disassembled, the cylinder-valve chest being one case in question. I decided to fully put this together in a permanent manner and the first job was to locate the gallery block to the cylinder. This is secured by four M5 socket head screws but I think it needs more than that. I epoxied it to the cylinder using the Chinese Araldite rip off from Banggood. (Excellent results, less than one third the price.) The sides and bottom were assembled using Cyberbond flange sealant. I have had good success with this product, unfortunately it is expensive and is sold in great big tubes with hardly anything in it which does nothing to generate warm feelings toward the company. At this point I checked the other parts of the engine, mainly for fit and accuracy when assembled. The slight curve in the base plate was causing a few deviations that I knew would cause the machine to run tight, so I stiffened the underside with two steel bars under the crosshead and a full steel plate under the main bearings of the crankshaft, this all helped but the final analysis will have to wait until the first run. Next will be the eccentric for the slide valve, my dear wife would say that I was the perfect person to make eccentrics but I won't enter into that. Pictures to make all this clearer, Cheers, Peter.


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## peter2uat (Aug 1, 2019)

I've read that you can remove broken steel screws/taps with a stiff & hot Potassium alum [KAl(SO4)2] solution which will eat away the steel and leave the aluminum intact. That's the crystals we use as Deo sticks or to desinfect/stop bleeding small wounds (after shaving) and may be found as "alum powder" in the spice section of grocery stores for pickling veggies/fruits. Drug stores/pharmacies could be another source.
Peter


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## peter2uat (Aug 1, 2019)

There is some similar and much cheaper product - *Loctite RTV Red* at $ 5 for 80ml which has the added benefit of being heat resistant too.


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## deeferdog (Aug 4, 2019)

Thanks for the tips Peter, I'll try the Loctite when the Cyberbond is finished. The making of the eccentric wasn't my finest hour. The drawings advocate making it in two parts, the outer flange being a separate item that is attached with a fastening. This method allows the eccentric ring to be made as one piece and just slipped on I decided to stick with the way I had made them before, that is as one piece with a split eccentric ring. The ring making went OK but the actual eccentric was a pigs ear. I miscalculated the offset, never a good start, and after an hour or so of clunk clunk clunk offset turning ended up with an eccentric shaped piece of scrap. I just couldn't face the prospect of doing the same thing again, so the second time around I set the roundstock up in the mill and bored the shaft hole the offset distance from centre, then turned the hub in the lathe and soldered it to the eccentric. How's that for cheating! Actually, it turned out so well that all future eccentrics made be will be done this way. Only thing left to make is the valve rod end and the valve guide, I'll do that in the next post. Thanks for reading, Cheers, Peter.


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## deeferdog (Aug 7, 2019)

The final parts of the engine are now starting to come together. The eccentric coupling was a smaller version of the connecting rod one and for the intermediate bearing I used one of the posts I made for the discarded version of the crosshead. Setting up the eccentric involved making sure the slide valve uncovered each port equally in its travel, then the steam chest cover was buttered up and screwed down. For the piston ring I used an O ring. It was too large so I shortened it until both ends just touched when fully home in the groove. Buttered up and attached the head. Added inlet fittings, connected air and after a bit of adjusting of the eccentric position on the crankshaft the engine snorted and came to life, albeit briefly. Quite pleased. Now to pull it all to bits for the painting, lagging the cylinder and tweaking the assembly. All that in the next post, how exciting. Cheers, Peter.


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## deeferdog (Aug 7, 2019)

Here is the link to the first run of the mill engine. .    Cheers Peter


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## Picko (Aug 7, 2019)

I'm following Peter. Nice work and photos, and runs nicely too.

Cheers John


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## deeferdog (Aug 11, 2019)

Still a bit tight John, will be better after tweaking which I will do after the painting. The whole engine was disassembled down to the main sub assemblies and washed in hot water and detergent. The hole in the flywheel (needed to access the grub bolt when it was a transmission pulley) was filled with bog and ground down. After a coat of primer I applied three coats of Brunswick Green to the engine and base and Heritage Red to the flywheel. I just use spray cans and I'm no expert but I was happy with the result. After the paint had cured most of the fastenings were replaced with stainless steel as I don't like my nuts and bolts painted. I reassembled everything and paid a lot of attention to alignment and fits, I think it will run much smoother when I fire it up again, which I will in the next and final post of this Mill engine. Only the teak lagging to fix to the cylinder and a bit of brass bling to go. Onward and upward, Cheers, Peter.


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## deeferdog (Aug 14, 2019)

Finally, the final post but one for this engine. The assembly went well, a couple of shims here and there to improve the various alignment issues, mainly the three main crankshaft bearings, they were drilled and reamed as one unit, but next time I would bore them, also I think that they would have been better made from steel rather than aluminium. On the cylinder I used double sided tape to affix the teak lagging, then lightly sanded and finished with three coats of gloss varnish. The brass hoops were cut from an old fire extinguisher, polished up and slipped on like an old fashioned bicycle clip with a bit of super glue to assist. I had an old brass lamp in the gash box so I took the base off and added it to the cylinder head for a bit of bling, the Victorian era being quite partial to bling. A bit of oil here and there with a few tweaks of the eccentric and it puffs away quite nicely on 15 psi or so of air (see next post for the video). So, there it is, Mr Benson's Mill Engine. Well worth your consideration if large steam engines are your thing, the last photo shows it alongside the beam engine I built some time back, I think they make a nice pair. Hope you have enjoyed reading about this construction as much as I have building it. Thanks for all the comments and your time. My next project is the boiler. Cheers, Peter.


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## deeferdog (Aug 14, 2019)

Final. Link to the run, operating on 15 psi air.   Cheers, Peter.


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## johnmcc69 (Aug 14, 2019)

Really great work peter! A fine companion to your beam engine!
 Looking forward to the boiler build & the steam up.

 John


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## Picko (Aug 14, 2019)

Looks and sounds great Peter.

John


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## bobden72 (Aug 15, 2019)

Runs and sounds very nice, just don't like the Allen bolts should be hex or even square nuts.  Love the decoration on the end cylinder cover.


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## deeferdog (Aug 16, 2019)

I agree with you. I'll swap them out for studs and nuts one day. Cheers, Peter


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