Entablature Steam Pumping Engine

[Rivergypsy]

Thanks, Maryin - I'll soon have some pics of the connecting rod with it's straps and bearings, hopefully

 

[Rivergypsy]

At last - more progress!

I've had the CNC running a bit more lately, making blanks for some of the next parts I've got modelled - the sliding collar for the governor, the tops of the feed pump pillars, and one of the links for the feed pump motion. I had some 30mm dia stainless, and milled the first op, before going back to the lathe, parting them off, and the finish machining. The only part complete is the governor collar, but hopefully the rest will be done by tonight

I'm also aiming to get the side ops done on the governor lever asap too - itching to get some motion work linked up here, so I'll have to go back to SW and get modelling again, as I've nearly finished making what I've done so far...

 

[Rivergypsy]

Here we go - a bit more progress made yesterday, with the side op on the governor lever getting done. It was a tad bit twitchy (me, rather that the work, lol) around the fork, but got there in the end. :hDe:

Initially I left it on the two supports while I started cleaning it up with file and emery, and the hacksawed off the tail support, and got that filed to shape. I'll carry on tonight to get it to 800 grit, and then remove it from the remainder of the billet.

I did get the feed pump gab lever done too - first op on the CNC from 30mm dia bar, then parted off, before holding on the boss with a 5/16 collet and facing to length, and drilling and reaming for the 3/16 bore

Next step to second op the tops of the feed pump pillars, get bushes in them, and get a shaft made... Oh, and hopefully the fork to carry the governor lever too

 

[Rivergypsy]

Just a quick question for you all, but I'm pondering flywheel materials - I know traditionally it's SG iron, but as I'm probably going to leave the engine in bare metal, I'm wondering if to go for steel. It'll be a lot of milling, as the billet comes out at 14kg, but tempting...

Any thoughts, please?!

 

[idahoan]

How about a nice slice of Durabar?

 

[Rivergypsy]

I've had a look for Durabar in the UK, but no luck. Thanks for the idea though, it does look nice to use.

I keep worrying that although iron is easy to machine, the colours won't match...

 

[idahoan]

I didn't realize that you were in the UK I thought that Thor Labs was a US company.

I used to work on photo mask aligner (OAI) that used a Thor Labs actuator for the theta movement.


Dave

 

[Rivergypsy]

Ah, sorry about that - they're all over the shop, lol

 

[Rivergypsy]

A bit more progress yesterday - here's the tops of the feed pump columns in place, with brass bushes, stainless shaft, and the link to pick up the gab end of the eccentric rod

 

[Generatorgus]

Hi Dave, I have to plea ignorance here, I've ignored your fantastic build here simply because I had no idea what entablature was.
I've seen entablature engines and love them, just never heard the term, in fact, I've contemplated an electric type in that style (much simpler) for years now, way before I got my machines.

At any rate, I'm just catching up and your work is beatiful, I just can't say much more.

You can bet Ill be following!!!

GUS

 

[Rivergypsy]

Hi Gus,

Many thanks for you kind comments, and glad you like it so far!

I know what you mean though, it's an unusual name. I'd heard of table engines before this, but I guess this is an earlier name for them. As soon as I saw Gentrys etching of the engine in the plans, that was it - hook lline and sinker, lol.

What sort of layout had you planned for your electric engine? Just a thought, but if you had a brushless linear motor or solenoid hidden in the cylinder...

Thanks again though,
Dave

 

[Generatorgus]

Dave, I'm thinking the electric engine will be solenoid powered.
Not sure about the layout yet, I have to have a few more sessions with my butt up against the wood stove.

GUS

 

[Rivergypsy]

I guess the only thing with solenoids is the clonk as they hit full travel, although you may be able to damp it to a degree. If you went brushless though, it would be silent Windings within the cylinder, and a piston made from thinwall stainless tube stuffed with opposing disc magnets...

 

[Generatorgus]

Dave,
Back up to my last post (or this post, I just figured that out) and take a good hard look at my avatar.
Tattered clothes, unshaven a beer in my hand....I think I'll stick to the simple unrefined solenoid theory, although, I always thought something like you suggest might make one hell of a cannon.

This is the last one of a few electric models I built.
All of the major components were salvaged from an ancient crating factory of major electrical manufacturer, including the cherry base.
The solenoids were from a magnetic starter in that building, flywheel from cart(really tough to turn..hard iron.)
The solenoids fire 180 and the only noise is from my sloppy fits in all of the linkages.
Engine frame is hand bent sheet metal angles silversoldered.
An old worn out Atlas lathe was all I had at the time and I used it only for the flywheel, the flywheel wobbles anyway, my trademark.

With the triggering contacts on each side, you can fire one or both cylinders and it is variable speed.

GUS

 

[Rivergypsy]

Now thats cute, I like it!

I know what you mean, but it's just the thought of a silent engine that I like. If you get the urge to go brushless then give me a shout and I'll see what I can do to help you, mate

 

[Rivergypsy]

Btw, your avatar? If I grumbled I'd be the pot calling the kettle black ;o)

 

[Generatorgus]

Dave,
"Silent engine", even though I collect and do minor repair on antique generators I'm in kindergarten electrically, (we only got up to transistors when I was in college and the computer we had was larger than my shop), but if I get a wild hair, yeah you'll hear from me.

 

[Rivergypsy]

Here's a bit more progress from the weekend. I finally got the governor lever cut off of the remainder of its billet, fettled up, and fitted to its pivot in a nice running fit. Found a stainless dowel too - nice not to have to make all the pivots!

At the end of last week I got the top of the governor arm pivot CNC'd to shape, including the profiled slots in the sides for the arms which I did with a 3mm slitting saw. I then milled the back off, before tapping M4 in the base (using the 1.6 pivot holes for alignment), and then mounted it on a M4 set screw in a lathe collet to turn the finial. Fiddly work, as it was doing its damndest to chatter, but with some sharp HSS and then hand blending/scraping, I think its come out quite nicely.

Last night I started fettling the governor arms (cnc'd from 3mm gauge plate, and then held in a collet to turn the ends down to 2.5 dia), only to find that the slitting saw I'd used to cut the slots in the pivot had too big a radius and the arms wouldn't quite go where they should, so yet again it was another needle file session to ease them into place. One done, one to go tonight... :wall:

There should be some 3/4" 316 stainless balls turning up today, so hopefully I'll get those drilled and bonded into place today ;D

What I've been using for some of these joints, which I'd whole heartedly recommend, is Araldite AV170. It's a heat cure single part epoxy, which cures at 160deg for an hour, but the bond strength beats the anaerobic adhesives we have here hands down. Well worth a try!

I'll have to get another camera, or my IPod repaired so that I can get some more machining pics again soon too, but in general I hope work will be speeding up on this, as (and I can't quite believe it myself) I've just been given a Colchester Chipmaster for my home workshop... woohoo1woohoo1woohoo1

 

[Rivergypsy]

And a bit more - the eccentrics are up to Op1, so shortly I'll be skimming the back of of them and then holding in a collet for the back turning. Hopefully tonight the governor arms, will be mounted too - just waiting for the epoxy to dry on the balls...

Here's a bit more of the modelling on the feed pump too - it's not quite in proportion yet, but heading in the right direction I think. There's another question though - I've only got stainless here for the pump bodies, but will it look odd with stainless pumps either side of the cylinder???

 

[Rivergypsy]

Governor nearly done - just two links to do...