My AJ Reeves Bolton Triple Expansion Engine

[suctionhose]

For what it's worth, I make my studs from socket head screws, high tensile bolts or commercial grade bolts having sufficient plain shank.

Cut the head off, hold the threaded portion in a split, threaded bush in the 3 jaw or locknut into a tapped hole and cut the short thread on the plain shank.

Nice rolled thread for the nut. Plain shank rather than that horrid 'studding' of today. Tight fitting thread in the casting (to suit the tap you own).

Grade 12 is not for carbon steel dies. The M5's M6's I would screwcut. Small stainless studs - a die in the tailstock is fine.

[dalboy]

Whilst I agree with some of the comments about "It is your engine you do what you want" from a personal point of view it would bug me if it did not look right for a steam engine whether a copy of an original or one that someone has designed as a running model.

I am enjoying your build and always look out for any updates that you post

[simplyloco]

Jan 1, 2023 10:04:56 GMT dalboy said:

Whilst I agree with some of the comments about "It is your engine you do what you want" from a personal point of view it would bug me if it did not look right for a steam engine whether a copy of an original or one that someone has designed as a running model.

I am enjoying your build and always look out for any updates that you post

I appreciate your comments. As has been suggested elsewhere, when I have time I can always replace the bolts should I feel the need, but in the meantime I save a great deal of time and effort.

[simplyloco]

Cylinder Bottom Covers



A four jaw chuck and a rotary table are required to complete these. I've done the 4 jaw work this morning, but the profiling will have to wait until the next rotary table setup. Here's some pics







These three were quite easy, it's the next bit that was tricky!







Switching to the 4 jaw chuck. I used the 7/32" reamer to give me some idea where to locate the cover. The jaws just touched the work enough to hold it and the reamer was withdrawn.







The cover is not very thick, so a pair of parallels have to be found that fit the supporting role. I have a box of wavy parallels that were just the job! Once the cover was knocked onto the parallels it was clocked up with the reamer in place.







All done, waiting for profiling and drilling. A good morning's work!

[simplyloco]

Drilling the Covers using a Dividing Head


We are not visiting family until this afternoon, so a quick two hours in the workshop was called for! I haven't used one of these since 1977, so I approached this little job with some trepidation. I needn't have worried, as it's just like riding a bike...

I had to look this up as I had forgotten how to do it!



Dividing heads can cost thousands, but this is a cheap Chinese plate (£42 for a set of 3) bolted on to my not so cheap Vertex rotary table. You can see two brass movable arms: these determine where you will land up after each hole!



The result. 12 equally spaced holes which will fit in any position on the cylinder - unlike centre punched ones...!



One down, five to go! I will use them as templates to drill and tap the cylinders.



Proof of the pudding. Bottom cover drilled 2.6mm on same setup.

[simplyloco]

Cylinder Bottom Covers - Last two



Just a repeat of the last post except that the last two covers have some holes missing on the PCD, so I had to be careful to 'lose' them in the right places! Here are a few pics.



This bottom cover has two holes missing fore and aft. leaving the others symetrical about the centre line. I made a guide arbor and stuck the top cover on with Loctite and positioned it by eye!







When the bottom covers are fixed in place I'll machine the edges to size parallel with the body. I'm getting a real buzz now and I'm champing at the bit!

[simplyloco]

Profiling and fitting the bottom covers.



They fit! I will next machine the cover ends to size. When that is done I can get the flanks in the right place to line up with the big cast legs.

[simplyloco]

Completed the Main Body, then Disaster Struck!


I have now profiled the covers, tapped the major M2.5 holes, fitted them top and bottom, and here's the result. I now know what it is going to look like and I am well pleased. Unfortunately, you will see in the last two pictures where I went wrong and it isn't adjustable...😱

Here's pretty!



Bottom covers in place but all is not what it seems...



I machined the flanks and edges in situ, leaving a few thou clearance for the carbide slot drill. I'd just returned from my monthly eyeball injection, and obviously didn't leave myself enough time to recover, and didn't notice that the cutter had crept out of the collet!



This is the result. Thanks goodness the error is underneath, and the cladding will hide it. Only you lot know that the error is there: don't tell anyone!

[mbrown]

Bad luck! But it happens to all of us. Maybe we need a new thread on "how to cover up your bloopers as painlessly as possible"....

You engine will still look a treat.

Malcolm

[simplyloco]

Jan 6, 2023 19:46:27 GMT mbrown said:

Bad luck! But it happens to all of us. Maybe we need a new thread on "how to cover up your bloopers as painlessly as possible"....

You engine will still look a treat.

Malcolm

Thanks Malcolm. Thank goodness I can hide this blooper. I intend this to be a legacy showpiece!
John

[ettingtonliam]

Just sweat some brass blocks into the grooves, and file flush. As we used to say in Ireland 'Sure, it'll be grand.'

[simplyloco]

Machining the Stands (Legs)


There are six legs: four singles and two attached to the condenser. Today I'm looking at the singles.

They are tapered in almost every direction, and setup accuracy and consistency is the key to success. For this you need a fixture of some sort.

Here are some pics. As it's Sunday I only worked on one leg today. Oops! What am I saying...!



Here's the completed fixture. It's a piece of 10mm thick alloy plate, accurately machined square. There are two 5.9 mm holes on the exact centre line, about 30mm apart. The leg face that is fixed to the plate has two M6 tapped holes in the machined datum face.







I don't have a robust end mill long enough to complete the other end, but matters not as the unmachined part is redundant and will be removed.







Success! It is supposed to be 4 29/32" long, so I have half a thou in hand. 🙂

[flyingfox]

Greetings Malcolm, good work on the engine, perhaps you would like to build mine when yours is finished?
I noticed you are machining the columns individually and wondered if the six (4 + 2) columns could have their lengths machines together? This seems to be the critical length.
Also, not sure if you noticed the set of machined cylinders and base on eBay at the moment.
Regards
Brian B

[simplyloco]

Machining the Stands (Legs) - Continued



Not much to show for an afternoon's work - but I can assure you it was occasionally hair-raising as my tools are getting blunt and consequently rubbing on the work. When this happens the cutter has to be stopped before withdrawing or it will dig in- as it did today..!

Just two pics. I have just concentrated on making to length only: the head sizes will be determined when it is bolted onto the main body and sits on the machined base.

Condenser next!


BTW, who is this Malcolm who is building a triple as well? Come out, wherever you are!
John

[simplyloco]

The Condenser with legs


I received the new, razor sharp carbide cutters for aluminium from APT this morning, so I made a start on the condenser. I set the part up on the bed, against two dowels that I insert into strategically placed holes, thus ensuring squareness. The tool bits are magical, with no binding. However, I was a bit careless with my hands as the following will show...



This 12mm cutter (£25.00) is bright, shiny, and very sharp!







It is provided with this little plastic piece to protect the sharp edges when setting up, and also protects one's hands.







If you forget to use it, you get what you deserve: a chunk taken out of your knuckle!

I'm gonna take another little rest and turn some pistons, it's safer...

[springcrocus]

Oops! Like you, I've got plenty of workshop battle-scars.

Regards, Steve

[dalboy]

I think most of us have battle scars if like me they just will not stop bleeding due to medication I am on. I did wonder where the other legs went too. I know that you mentioned the condenser earlier in the thread. Keep going and avoid the sharp edges next time

[simplyloco]

Engine Bedplate


A productive two hours in the workshop today. I'm waiting on some bits for the condenser - copper tubes, brass plate and a 4-5" micrometer - so I have put it to one side. The bedplate is the next obvious thing to make. It has a lot of 'meat' on it, and I am reluctant to remove metal just for the sake of it. We'll see what it looks like when I've finished this stage.



#



The base was given the once over with a big file to get it as near flat as possible. The six faces were then given a light skim to provide a datum for the next op- skimming the base.





Turned over and clamped onto the 321 blocks and machined flat. The first pass wasn't enough as there was a casting lip on the LHS which had to be removed.





Turned over, clamped down onto the bed and machined all round. The drawing specifies just a 1/16" drop from the machined face, but I'll leave it as it is for the time being.





Sitting pretty on machined surfaces. I'll machine the main bearing slots tomorrow.

[simplyloco]

More Bedtime!


Surfaces and edges are now to correct height and width. Centreing up was made easier by the use of a parallel against the work and the two dowels inserted into the bed. The waggler is some handy gadget!





Before I started I checked the relationship of the stands to the cylinders and the bed. There has to be a precise gap of 1.25" between the guide bar faces and to my pleasant surprise it all fits together in the right places!







To depth but not width as yet. These APT cutters are super!

[uuu]

Looking good.

But - and I hate it when people do this, but I'm going to do it anyway - I'd have had more clamps. There, I've said it. I just get really nervous about things (the work or the cutter) moving during milling, so I'm a belt-and-braces man.

Wilf