5 Cylinder radial (winter's project)

[chuck foster]

george your going to be finished before winter even starts!!!

fantastic work as always :bow: :bow:

chuck

 

[ninefinger]

.... The only thing I'm not sure of at this point is whether to make the return side pump a little bit bigger (one tooth more on the gear), that way it will always be ahead of the oil supply.
George

Definitely a good idea to have the scavenge pump be larger than the supply. As the oil is collecting in the sump it will be full of bubbles. If the pumps are of equal size then the sump will become your oil reservoir and you will run out of oil in your supply tank. Common practice is to have the scavenge pump something like 50% larger to handle the extra air entrained in the oil. Perhaps instead of a different tooth count make the gears wider for the scavenge pump side?

Excellent build so far - I'm going to use your energy as inspiration for me to get going on my build.

Mike

 

[ShedBoy]

That sure is purty George.
:bow: :bow: :bow: :bow: :bow:
Brock

 

[CMS]

Extra clean work!!! Oh, hows the new mill working out???

 

[hobby]

Hi George,

As always, excellent workmanship,

I'm chiming in here to say,
Thankyou for the sequential step photos of the various operations, the way you have put these together, makes for a very good learning demonstration.

To just see a part already made, holds no educational product, but to see that part being made through the various steps, helps us to see how to machine difficult parts by breaking them down to bite size steps.

Keep up the great work...

 

[gbritnell]

Hi CMS,
I have the new mill in pieces in the basement waiting to be cleaned up and reassembled.
I will then be ordering new digital readouts for it so I'm looking at about 2-3 weeks before I'm back in business.
George

 

[steamin]

George, what brand of DRO are you planning to buy ? I purchased a SHARS on ebay for my mill and it is great. I just purchased a second one for my Hardinge HLVH lathe. Check them out. For what they can do you can not beat the price. Larry
PS: Happy Thganksgiving

 

[Admiral_dk]

Any chance for an update - I've really been looking forward to the next chapter in this odyssey :bow:

 

[gbritnell]

As many of you know I took on a job building hit and miss engines for the Ministeam company out of the Columbus, Ohio area. I am just finishing up the 5th engine since November, 2010. There was a break in the building process while they were waiting for updated drawings for one of the Galloway engines. It was at this time that I started making parts for the radial. I had already completed the drawings over last winter. I intend to get back on the radial shortly and would like to have it finished up for the NAMES show in April. One of the holdups is the cam gear that I designed into the engine is a 64 pitch, 60 tooth internal gear. Stock Drive Products has it listed in their catalog but every time I call on it they say it's back ordered and they won't have it for 4-6 weeks. This was about 9 weeks ago. My buddy has a slotting head for his milling machine so if worse comes to worse I could try and make my own.
Anyway thanks for your interest and I will certainly update the group as soon as I start making some more parts.
George

 

[petertha]

Hi George. I got looking at your valve layout as a reference to a drawing I’m working on. I was mulling over increasing my valve angle from 20 deg to 25 & got wondering about the implications of this steeper angle – pushrods then act on the rockers at a higher angle as they originate from center, more cam throw to get the required valve movement, pushrod flexing…. Heady issues outside of my league.

Other (non-scale replicating) model radials Ive seen appear in the 15-25 deg range. Eg the Edwards-5 plans show 20 deg & 0.093”dia drill rid pushrod. Overlaying some lines on your drawing, looks like you chose about 30 deg, is that correct? Any comments on this, or is it a no-biggey issue?

Also, (if I understand correct) your rocker perch’s are also swiveled outboard a bit. So the pushrods would meet them at a higher tangent angle yet vs if they were in-line = parallel to the crankshaft? What does this accomplish or intend to do on your design?

What is your plan for pushrods & ball ends, sockets & such?

 

[gbritnell]

Having just finished the 1/4 scale Galloway I was working on I got back to the radial build.
There is no order to parts making and while looking at the drawings I thought the master rod would be next. The first three pictures show the usual steps, picking up the edges with the edge finder, center drilling all the holes and then drilling to the required size. For the .125 dia. rod pin holes I first drilled through for a 2-56 thread. This was followed by a .120 drill and finally finished with a .125 drill. For the wrist pins you're probably asking why they were drilled and not reamed, well the .125 dia. holes had to extend .010 into the far cheek so that when the pins are screwed in place they would have a true location and not rely on the threaded hole. For this type of operation I use a new drill and with the .120 pilot hole it comes out dead on .125.
gbritnell

 

[gbritnell]

The remaining holes were drilled and reamed and the width of the small end of the rod was cut. I try to plan my cuts so that I always have some stock to clamp to.
The rod was then turned in the vise and the center area was cut out.

 

[gbritnell]

Next up was to remove the remaining stock from around the crank hole leaving a .016 wall. The bottom area was roughed out first then the rod was supported by a .281 drill and and rotated to remove the remaining stock in a radial fashion. You can see the small facets which will be filed out later.

 

[gbritnell]

Before tearing everything off the table an setting up the rotary table I cut a piece of stock to size and drilled and reamed for the slave rods.

 

[gbritnell]

The table was cleared and the rotary table set up. The first thing to do is find the center. I put a piece of round stock in the holder to roughly get the center then do the final dialing in with the indicator. The fixture block was set on the table and located into the large dowel pin hole with a .375 brass plug with a taper turned on it. I find that this is accurate enough for rotation milling of small parts. The fixture block was then clamped down.

 

[gbritnell]

The block was then indicated parallel with the X axis and the handle was set to -0- and a reference line marked even with any close number. The rotary table has a movable pointer but it's on the side away from the handwheel so it's just easier to make my own mark. The purpose of setting the block square is because the sides of the rod are tapered and this gives me a reference for rotating to the proper angle.

 

[gbritnell]

The part was then bolted down using the hollow dowels to locate both the crank end and the wrist pin end. The main diameter was cut while staying shy of the tapered beam until the radius number was established. Once I had the final reading for the desired diameter I rotated the table until I could 'paper' the cutter to the beam. With that radius cut I put a .25 dia. ball mill in to cut the 30* step down to the beam.

 

[gbritnell]

A .125 endmill with a small radius on the corner was used to cut the 'I' beam step in the upper part of the rod.
The final 4 pictures are of the finished master rod. Tomorrow I will make the bushings and wrist pins and finish up the slave rods.
gbritnell

 

[b.lindsey]

George,
After too long a while of not having enough time to spend here on HMEM, its finally nice to be able to read and follow some projects again. I went back and reread this one from the beginning yesterday and just wanted to say its as awesome, informative, and educationsl as always. Am really looking forward to seeing this one develop. Thanks for sharing your immense talents with us :bow:

Bill

 

[CMS]

Nicely executed procedure, as usual. I too have a 1/4 scale Galloway kit that I purchased from Dick Shelly about two years ago. His failing health prevented him from getting around much so his wife and son handled most of the dealings. Very nice people. Hope to see one of you Galloway builds posted on here one day.

Craig