Longboy's "PARTNERS" Model Engine! (Webster Twin)

[Longboy]

I've been looking at my iconic Webster periodically the last couple years. With an idea in mind.....

What if Joe Webster designed a twin version? Not too many horizontal gas engines favored in the forums beyond hit and miss. This fall was the year to develop that concept with just enough recognizable pieces, that all can see the inspiration for the PARTNERS engine was sourced from Joe Webster's model favored by beginner machinists world wide!

A short build log to follow!

 

[Longboy]

The crankshaft at the back of the parallel frame members mounts on top with a pair of caps. Here trying out some thin wall Oilite bushings. Not working well. They would not stay in place and walk out from under the cap. Tightening down the cap so they stay would gall the crankshaft. Replaced with roller bearings then.

 

[Longboy]

Most moving components for Partners are within the frame rails. These Tecumseh points set bolt on here and the insulated connection to the battery passes thru the frame just in front of the crank web. A flat spade connect for the wiring.

 

[a41capt]

I love it! Another vision of this iconic first engine. Now, maybe it’s time for me to take on the “Wetster”, a water cooled version, and perhaps even a twin like yours!
I’m looking forward to the rest of your build notes.

John W

P.S. I used roller bearings on my Webster build!

 

[Longboy]

Keeping the frame from being an inch longer with an up to 4 in. dia. flywheel plus to not crowd out components near the cylinders, the flywheel is turned 90 degrees with a pair of .5Mod, 20T helical gears. The MXL timing set is 20/40T and the 20 has plenty of room on the crank. Flywheel bearing carrier is off set from center of engine to give the desired alignment clearance for the sprocket.

 

[Longboy]

To get all the shaft components on one shaft up front, the engine would be wider by about 3/4inch. Distributor drive, two cam lobes, cam drive sprocket, and points trigger cam. As it stands, Partners is only 3/16in. wider at the crank bearings than the Webster adding a second shaft here.

 

[Longboy]

The two shafts split the driven necessities that make Partners run. A pair of 32P 24T Nylon gears space the shafts apart to clear the flange on the cam sprocket as the second shaft behind drives the distributor and triggers ignition points. Shaft collars secure some thrust movement of the shafts in their bearings at the outside frame. Flats for #6 set screws for the sprocket and gears only. Cam lobes and points trigger cam need variable positioning on shaft for timing.

 

[Longboy]

Cylinder heads and valve blocks are recognizably Joe Webster, custom to the needs of Partners of course. Some eighth inch aluminum angle support the distributor body over the frame. Its drive shaft and brass gears between the inside frame and cog drive belt are there thru the miracle of the "just fits" theory!

Crank webs are 12L14 steel anchored to the crankshaft with #10-32 set screws.

 

[Longboy]

The ex. valve stem and the camshaft are at the same horizontal level. I'll be using these "hanging crows", to transfer the cam lift to the valves.

Profiled on a bar of Delrin before copy to brass, the ex valve is set back 3/8 in. from the fulcrum. The cam lobe sets back an inch from the valve stem. To gain the desired .080 to .100 in. lift at the valve, 5/8 in. diameter Delrin round stock was used for the cam lobes.

A side view on the relationship of the lifter bar, cam to valve.

In brass.

Mounted then to the front end plate and installed to frame.

 

[Longboy]

My home grown fuel mixers working well. Using a pair on Partners. Easy to make. No throttling. Engine speed varies by fuel/ air mixture.

Using # 14 needles. Seats drilled #55. 10-32 brass machine screws and 3/8 x 3/4in. alum bar stock for body.

One thing irritates me. You can not buy a package of sewing needles in any one size. Seems they are sold only as variety packs of assorted sizes.

 

[Longboy]

Plumbing up some fuel supply with half inch copper tube. To get any kind of volume at this diameter, a couple of tees extend the capacity right under the frame.

Complete with filler neck and outlets to the mixers.

Four nylon pipe straps hold fuel tank in place. Partners has a slight downward rake to the front for flow to the pickups.

 

[Longboy]

The PARTNERS engine completed and running. Come back this weekend for its premier with the beauty shots and video! ... Dave.

 

[Longboy]

Betcha there are a half dozen here following this log that have built the WEBSTER.

Betcha another ten have used ideas from an engine built from plans in their own scratch builds.

And I bet a few have taken a second look at an established plan and expanded on the original model in homage to its developer.

Thank you Joe Webster where ever you may be! Over ten years and about fifteen gas engines, remembering where it started....... going from Stirling builds to gas!

PARTNERS started last week of Oct. Completed middle of January.

Another's idea becomes a custom build.

Video follows. Thanks for coming by! Dave.

www.youtube.com/watch?v=BKkpuezJAYw&t

 

[CFLBob]

Dave - I'm in awe of this. Starting in October and having it running by January is amazing. A very neat engine; runs great, sounds great, doesn't wander off the table.

Like most people, I built a Webster as my first IC engine, only it took me darned near a year and it never ran as nicely as this. I originally thought you started when the thread started on Feb. 4, which would be totally insane. I'm not sure I could identify, order and have received the gears alone in that little time.


Bob

 

[Longboy]

Thanks Bob. Horizontal engines need less ballast to weigh them down to keep them from jumping around on the table. Low center of gravity and the power strokes are across the table instead of 90 degrees to it. Items like the gears show up from China around 15 days. Not bad with the disrupt in material backlogs. You are still involved after your Webster. Joe definitely left his mark in the hobby. ... Dave

 

[a41capt]

Dave, nice nice, nice! Really love the homage to Joe Webster. I too have built a Webster and after I complete the Pioneer I’m currently working on, I think I’ll start on a “Wetster”. Water cooling, propane fueled, and electricity generating!

thanks for sharing your vision,
John W

P.S. Another Arizona boy

 

[Longboy]

You are welcome John! "Wetster" to be a breath of fresh......water for you! Got a DC motor for the generator in mind?

 

[a41capt]

You are welcome John! "Wetster" to be a breath of fresh......water for you! Got a DC motor for the generator in mind?

I have a small 12 volt motor scavenged from a rechargeable drill that met a terrible fate when it fell from the roof of my Mormon Lake cabin while I was building it…. I figure it’ll do for charging cell phones or my iPad!

John W

 

[ShopShoe]

Lots of moving parts to watch on this one. Great job on figuring out how to turn the original Webster into a twin.

Your build speed on this is also incredible.

Congratulations and Thank You for posting.

--ShopShoe

 

[Longboy]

Thanks ShopShoe. Retirees have the time to make the builds proceed quicker. Time line seems to work for me week to week.