1/4 Scale Rider-Ericsson Pumping Engine

[b.lindsey]

I worked some on finishing up the displacer yoke castng Friday and yesterday got the shoulder bolt made to attach it to the flywheel support bracket. Today I hope to work more in the ID of the power piston though there is slight list of household duties of the non-machining variety to be accomplished as well. Hopefully there will still be so time in the shop too!!!

 

[b.lindsey]

With all the senior design capstone projects to be completed by this Thursday, the machine shop has been busy so not a lot of machine time for me. I did however finish the install of the cylinder liner into the cylinder casting today Photo 1 actually shows the lower end of the liner inverted so as to apply a generous amount of JB Weld. This area will mate with the lower machined ID of the casting. Once this was inserted and lined up, the upper ring was similarly coated with epoxy and then the whole liner was tapped into place with a soft face hammer and a block of plastic to insure even force all around. Photo 3 shows the liner in place after cleaning off the excess epoxy from the upper joint. I'll let it cure overnight and check for water tightness tomorrow though I don't expect any leaks. Neither is the liner coming out anytime soon

 

[lazylathe]

Looks like it is starting to come together now Bill!!!
The liner fits perfectly and you should have no leaks there! ;D

Have you decided on a paint scheme for it yet?

Andrew

 

[b.lindsey]

Andrew,
Not fully decided yet but leaning towards a dark maroon color though the firebox will likely be a high temp black. Hoping to add some pinstriping too...maybe gold or silver. All black seems a bit boring but will have to search and see what I can find in a maroon color...definitely want it to be more red end of the scale rather than blue or purple. Thanks for following along!!

Bill

 

[b.lindsey]

It has been a slower week as far as progress as other things took precedence, but looking forward to a productive weekend. Most of the work on all the castings is done now, so its down to the bar stock items, links, etc. I did get a little done on the power piston last evening...facing to length, grooves in the face as per the print, and the notch at the top for packing (photo 1). Concurrently, I have been working on a version of SandyC's burner for his 3" vertical boiler, though I made the main body out of a chunk of brass as one piece rather than copper pipe with a bottom plate (photo 2). The deflectors, gas jet carrier, and mixer tube will be made this weekend and silver soldered together. Ordered the orifice yesterday from McMaster and it should be in by Monday. Still looking for a suitable ceramic material on this side of the pond, so if anyone has any ideas on that it would be appreciated. Finally the various pieces of brass stock have been cut for the linkakges needed and will be working on getting them machined today and over the weekend as well (photo 3). Hope to pick up the pace some and get this one finished by the end of May or early June at the latest.

 

[b.lindsey]

Before leaving work yesterday I milled all the link pieces to length and located and drilled the holes (photo 1). More on these tomorrow though. Today I finished the parts for the burner body and goet them silver soldered and cleaned up on the outside. This is shown in the next three photos.

 

[b.lindsey]

Before setting up to work on the linkage parts, there was some rotary table work required to finish up the power piston casting so I worked on this most of the afternoon. This is actually one of the more intricate parts of all of the castings, Today's efforts are shown in the photos below

 

[b.lindsey]

Finally for today, I made the nut that will attach the piston rod to the piston and whoch acts as a guide for the displacer piston' Its not thresded yet to the 1/2-20 required...I'll do that monday at work. Tomorrow I will begin machining the linkage parts.

 

[b.lindsey]

Yesterday did see some progress on 3 of the 5 linkage parts. The other two I will work on today at work as time permits. The two power piston links had to be flycut down to a thickness of .18" from the .250" thick brass stock but once that was done, the side reliefs could be gang cut as shown in photo 1. Photo 2 shows both of these after that operation. Though not the most efficient method, the face reliefs were cut with a ball end mill on each side of these two links. As noted, not the quickest way to do this but more secure on the little Sherline where this was done (photo 3). Finally the slightly longer and full .250" thick displacer yoke link was done similarly. All three of the links are shown in photo 4 after these two operations. Radiusing the ends of all of the links will be done together once the other two 3/4" thick links are completed to this same stage. Hopefully the orifice for the burner will arrivei today so it can be installed.

 

[lazylathe]

Great update Bill!

A question:
I see you used a ball mill to cut the face reliefs.
In the next picture it looks like you swapped cutters and now have 90 degree corners.
Any reason why you did not just use one cutter for the whole operation?

Andrew

 

[b.lindsey]

Andrew, the 90 degree square sides were cut as shown in picture one. The radii on these side edges will be formed when the ends of each link are machined "round". In photo 4 the upward faces (and opposite sides as well) were done using the ball end mill, so that there will be a radius curving up to the flat face(s) of the still to be rounded ends of the links. Hope that helps...if not will post a picture once they are completed.

Bill

 

[b.lindsey]

These pictures show the roughing out of the wider links...milling the center slot, the rounded side reliefs and the squared off end reliefs. I will put the radii on each end of them tomorrow.

 

[b.lindsey]

I did get the radii cut on the three thinner links today, then buffed them tonight at home. Those are shown below.

 

[ProdEng]

Nice to see how the links where made, thanks.

Jan

 

[lazylathe]

Thanks for the last close up Bill!
Now it makes sense!!!

Gorgeous work as usual!!

Andrew

 

[b.lindsey]

Glad that helped Andrew. They actually look better than they do in the pics, but before assembling, I may try polishing them a little more. I need to get some more use out of that little Foredom buffer anyway, but since I have never been big on polishing things, I'm learning as I go. Hopefully will have more to show later today or this evening.

Bill

 

[kustomkb]

That's some nice work you're doing on your latest project Bill.

I am enjoying following your speedy progress.

 

[b.lindsey]

I had a little time this morning to get the wider 3/4" links radiused on the ends. Photos 1 & 2 show the set-up used which was basically the same for the flat links...two close fitting pins spaced at the center distance for each of the various links with the end to be radiused centered with the rotary table and spindle then bakcing off the desired radius (which in all but one case was .250"). Actually I backed off more and gradually worked closer to the desired radius taking relatively fine cuts each time. With the wider links I had to shim under the elevated end opposite the fork as shown in the second photo. All in all it worked well and seemed a safe and steady way to go about it. The sacrificial aluminum piece looked more like swiss cheese once done but it served its puspose. The last two photos show the two machine finished fork links. Buffing will be done tonight. The small side radius on the faces of the forked ends is a result of the brass bar stock which came with slightly radiused edges but this is cosmetic and won't have any effect on their function.

 

[b.lindsey]

Thanks Kevin, we must have been posting at the same time. Um....compared to the Briggs build most anything is fast but this has been a most enjoyable project so far. As i noted at the outset, this one has been on my "most wanted" list for like 13 years or so, and I've had the castings for over a year. Thankfully the build is going a bit more rapidly.

Am expecting another shipment of goodies today from McMaster which should finish out the materials needed. Some stainless rod for the pump, some 3/8" hex 12L14 for the various shoulder bolts that have to be made, teflon packing for the power piston, and the 3/16" square steel for the displacer yoke.

BTW if any of you that are planning on building this one need a 1/2" x 3" dowel pin for the crankshaft or a 1/4" SS ball for the pump, let me know as I have 4 and 24 extras respectively what with minimum package quantities and all.

Bill

 

[b.lindsey]

The power piston has a cap that fits on the top of it to form a groove for the packing material. Not having any '060 brass handy i made it instead frome a larger piece of brass...turned and bored to size on the lathe, then drilled for the attachment screws and routed out for the clearance of the link attachment bolts usint the rotary table on the mill. Rather than returning to the lathe to part off the .060" washer like part, i cut it off instead on the RT with a slotting saw which worked very well. It all fit well together and still has a nice fit in the cylinder.

Will be working on a few more smaller parts this weekend including the shoulder bolts now that the 3/8" hex stock is here.