Borderer Piston valve version

[RReid]

That is a good looking crankshaft, well done! Numbering parts & location as you've done with punch marks is a good plan and a simple method.

[Team ricky]

Cheers chaps

It’s certainly the tricky part of the build ! That and getting the cylinders spot on


I made the two outer bearings today and mounted them to check the crank spins and is true and I’m pleased to say it’s absolutely spot on ! No dial movements at each end and central journal spot on too !


Just ordered a bit more bronze to make the central bearing - it’s a bit more involved as it’s split prior to machining which im looking forward to …

Just ordered some bolts too as making a load slows down the more important jobs

[Team ricky]

Here’s all bearing blocks and shell bearings made

Crank spins over great with clamp pressure on the bearing caps, Im sure it will be great when bolted too!

I might make some oil cups later or machine the flywheel

[crueby]

Shaping up nicely!   

[Team ricky]

I took the plunge and did the ports

Milling the slots was good but the tricky bit is drilling the holes through to the cylinder….

I milled a flat spot as per the drawing and used my dremmel to get the paired holes going at the correct angle , then just pistol drilled them so I had a feel for when the drill was ready to break through, I don’t think a pillar drill would be good on a 2mm hole breaking out at an angle on an interupted cut !

Worked a treat got the holes spot on …

[Team ricky]

On to the rods

Because of the crankshaft bearing CL height is 3mm higher than drawing I have to reduce all rods by 3mm

Not a huge deal but the drawings again not giving the dimension breakdown as you would probably produce the part ! Plus Imperial so a pain as always…

If anyone is good with imperial I’m looking to have a length for the rod blank (drawing shows to CL of Gudgeon pin)

A total overall length would be good to have when parting off ect …. The dimension would be minus the rectangular base (separate part)

I’ll then drill and tap the centre of the rod and fixture it to the rectangular base and maybe silver solder too…

The top rod features I can complete on the mill and rotary table !

[Admiral_dk]

I'm with Jason on this one. Take a Calculator and do all the calculations - then choose a reasonable Metric equivalent. Jason often use 24mm to the Inch.

Bevare that shorter Rods has bigger angles during the movement - so test extra for Interference !!!

Per       

[Team ricky]

Yes it’s worth it at this stage!

I thought about the angles and figured taking relief from the bottom of the standard would be a quick fix if there was any binding!

That would need a little off the cross slide too

If it looks like a major problem I can re-make the collums to eliminate the crank line relationship error well not so much error as it’s the only dimension that gives the crank clearance to the base plate….. I’m still totally stuck as to how this is incorrect on the drawing but hey ho !

[Michael S.]

If I understand correctly, you may need to lift the cylinder block up.
Maybe the 4 columns don't need to be remade and you can extend the columns with specially made-to-measure discs. I noticed that the columns are not flush with the base plate. It is always a problem when the thread does not go all the way to the edge. Then the threaded hole must be enlarged a little more above. with the countersink drill or you can then use discs to create the necessary increase.

Michael

[Team ricky]

Hi,

Yes the collums were not tightened down in the picture ! They do tighten and register but as you say 4 spacers could be a simple fix , im probably happy to complete one rod, make one standard and cross head and try to see how the geometry goes , I do like your idea as I have material left over so it would be seamless pretty much !

[Michael S.]

I had to do it like this before and made the pane a little bigger and rounded it off at the top. I think it looks like it's part of the design and is less noticeable.

Greetings Michael

[Team ricky]

Excellent solution


I did make the standards/trunks and one gland bottom cover, all snaps on registers and a good fit !


I maybe need a tap for the gland side but not deciding yet on a metric solution to save cost on tools all the time … m8 probably is best here

[Team ricky]

Here’s a bit more done ✅

Top and bottom coveres fitted

Trunks fitted too .. Hopefully I’ll do the big end and try a rod out !

One thing that is wierd on the plan is it calls for a 5/16 thread on the underside of the top covers, I can’t think of any reason for the thread ? It’s effectively the gap where the piston nut lives at TDC

[Team ricky]

A little more done today


Does not look like much but I made both big ends ready to accept the rods which I’ll through bolt and silver solder I think 🤔

They are a little tight to spin so choice here between running in and slowly adjusting the bolts afterwards (long run)

Or because I went with 7.9 reamer and 7.9 crank I could use the 5/16 reamer I brought and get 7.95 for the bearing , probably the way forward……!

[Team ricky]

A little more done today , I made one rod completely minus the 3mm and trying it in its hole all seems good !

I’ll make a cross head and give it a full test before making a second, Should be fine but you never know….
The rods are mild steel as per drawing so I’ll definitely try the nickel plating on these parts