5 cyl OHC Radial.

[Brian40]

Hi
The RT has T nuts that are hand fitted to the slots to ensure that zero is maintained. the jigs are centralised by a MT.

The crankcase jig has a adaptor ring to covert from male to female and a master dowel pin indicated by the craft knife.

The second MT fits the lathe to align both jigs on the face plate.

The holes are just to reduce weight.

Always happy to answer questions. Brian.

 

[Brian40]

It's been a long while but I am back in the shop, so this is the latest from you tube.
https://youtu.be/vf8YD7i-6kM
Brian 40

 

[rad45]

Hi Brian There are an excellent set of drawings available from a gent in north Germany, if you decide not to go to the trouble of designing your own.
I know his works as I built one to his design myself.
Jürgen Heinen [email protected]

 

[Brian40]

My apologies for not posting of late my heath has not been at its best , but I have managed to make progress in the shop some of you may have even followed the progress of the radial on the tube.
So to re kindle the flame here is the latest picture of the beast . it still requires pistons and oil pump etc but is coming along nicely

Brian 40

 

[petertha]

Keep up the work & health, Brian. Its looking great!

 

[johnmcc69]

Very nice! Looks great Brian!

Good to see you back at it,

John

 

[NickP]

My apologies for not posting of late my heath has not been at its best , but I have managed to make progress in the shop some of you may have even followed the progress of the radial on the tube.
So to re kindle the flame here is the latest picture of the beast . it still requires pistons and oil pump etc but is coming along nicely
View attachment 113131
Brian 40

Hi Brian, I’m new to this thread (not to mention model engineering as a hobby) but am following along with great interest. Glad to see you’re back at it and hope your health improves for 2020 and on. Cheers, Nick

 

[josodl1953]

Hi Brian, nice to see you back on track.
Jos

 

[bobden72]

Looking smart Brian.

 

[Brian40]

Thanks for the welcome back an all the good wishes.
I think I have the oil pump firmly on the screen now so it's time to push on.
Another view .

Brian

 

[xpylonracer]

With regard to slave rod location on the crankshaft to get all 5 cylinders to be on TDC at 72 deg intervals, there is an Excel file on the net detailing the dimensions needed to achieve even spacing, I have copy somewhere on a disc so could search if needed.

Marcus

 

[Brian40]

Hi Marcus.
To get the angles, I used my CAD program to draw the position of the master rod at each interval, then measured the angle for the new pin position. however it would be nice to confirm my findings.
Thank you for your kind offer.
Brian.

 

[Brian40]

Found a diagram in my file .
Brian.

 

[Michael Rosenbauer]

Hey Brian, impressive work. Looks great. I have never seen a radial with OHC. Is that your design?
Keep on healthy.

 

[xpylonracer]

Brian, simpler to get the files if you join the Radial and Rotary group as follows: https://groups.io/g/RandREngines
Slave rod centres layout by Brian Perkins, Master Slave, Radial Engine Balance.
You may also want to post some photos there of your engine.

Marcus

 

[Brian40]

Hi Michael.
Yes the design is original I think. I need something to keep the brain cells active, I will be 80 this year and need my workshop more than ever. you can find me on you tube search for Brian Hogger I am at the moment doing video number 14 on this build. but don't hold your breath.

Marcus thanks for the information,
Thanks to all Brian.

 

[Michael Rosenbauer]

Thats great, it is also my intension to keep the brain in a better shape.
I almost can do my job without thinking thats why I need a new challenge with 56.
You have my respect.

 

[Brian40]

I have made up a rig to test the pin positions on the master rod all the pistons come up at the correct 72° intervals so that's a relief.
Brian.

 

[petertha]

Hi Brian. Its been a while since I looked at this master rod / link rod compensation angle stuff. I know a lot has been posted on the forum previously, we could probably search for links. I have some of my files before 'the great PC crash' but not all. I still have my step-by-step (graphical) layout methodology, which I pilfered by someone on the old Yahoo R&R forum. I think I can make a PDF of that & post.

I might be remembering this all wrong so we may have to dig a bit deeper. But I seem to recall: assuming equal link rods/pistons/cylinder dimensions & radial layout, you can satisfy one parameter but not both. In other words if you have equal 72-deg layout on the master rod (365 deg /5 cyl) then you will have TDC occurring at 72-deg rotation. However the throw will be different resulting in different compression ratios across the cylinder. If you adjust the angle of where the link rod bottom end pin lays out on the master rod, you can achieve equal CR. But I think TDC will no longer occur at 72-deg, it must occur at some other crankshaft angle. On a glow engine, balanced CR is important if it varies too widely. The gas will fire when it fires, we have no direct ignition control anyways. On a timed ignition engine, I would assume the equal crankshaft angle is more important.

For example the Edwards 5-cyl has equal 72-deg layout, which by itself, results in significantly different CR across cylinders (spiky looking CR plot). But I think the design calls for altering the head shims or shaving the top of the liner lips to compensate. Maybe an Edwards builder can chime in. By contrast another radial I looked at, possibly the Kinner, shows an angular compensated master rod layout & more equal CR compared to master. And the parts are all machined to same dimensions.

'Carl Sorensen' does that sound familiar to anyone? He wrote an article & Excel spreadsheet? That's what I used to adapt into these summary plots. I really should go back & clean up the tools.

 

[Peter Twissell]

The old Yahoo R&R group was saved and is now [email protected]. Carl has been feeling his age recently, so I am now the owner of that group.
Carls spreadsheet is still there. I also created one (available on that group) which can handle up to 9 cylinders and also calculates balance.