building a new flame sucker

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madjackghengis:
Hi Nick, all, as a matter of fact, I'm going to be putting a valve set up very much like the poppin on this engine, the only difference will be the means of mounting the pivot, it will work exactly the same. What you said about the cam closing the valve, and letting nature open it, Nick, struck home, and that, along with almost getting it running, using a propane torch for heat, told me I was close, with it almost running, but would never get there with the valve arangement as it was. having the engine supported by an aluminum plate, right behind the head also meant substantial heat was being transfered to the frame without doing any work, so I'm moving it to the other end of the cylinder, which should be an improvement as well. Being a bit larger than "poppin" I'm going to try a piece of .004 leaf gauge, but other than that, it will be a "poppin" valve train all the way, and maybe I get to see it run finally. I've even got a nice piece of the brown stuff already selected and ready to clean up for the base, so it has to work, right? :lol: mad jack

NickG:
I thought you may be able to just make a modified arm / sort of bell crank with roller to sit on top of the cam and therefore close the valve and let nature open it as you say.

Not sure about moving the frame, it may help but I think these engines differ in that it's the hot gas that gets drawn in, once it's in there, more mass will surely help cool the gas. Hope it helps though and your plans to lighten the centre of your flywheel concentrating mass more around the edge is sure to help.

Once you've nearly got it running though you can't be far away. I think utilising a recognised working valve train will give it the best chance and if you've found some nice brown stuff it can't fail! :lol:

madjackghengis:
Hi all, been to the doctor for a couple of days, and gathering wood before that, been a bit cold in the shop, but I've got a good bit done in bits and pieces, so here's where it sits.

With a ten hole bolt circle, and the front end indexed 90 degrees from the back end, I had to make a new mount for the cylinder, and made it from a scrap of stainless I scrounged from a photo printing machine. It was pre-bent, so I just had to cut it to length, cut one side to match the other, drill the hole circle and center hole for the piston to go through, and put some holes to hold the piece of stainless shaft I'm going to use for the valve train pivot, re-using the setup which got sticky when it was sliding the valve up and down.

the cylinder and crank standard mounted, and the new pivot bar mounted, with the bushings pushed out of the deleted parts not used.

another view, showing the pivot bar relationship with the cam and the head

the head end, all cleaned up, ready for the new setup. I broke off a head bolt taking it apart, so I had to weld a bit of stainless rod to the broken end, and extract it, then lap the head surface of the cylinder, lapped the head just for good measure, too.

I was going to find a piece of aluminum and machine out everything that didn't look like valve gear, but thought maybe I'd fettle up this engine a bit, with some shiny parts, made of brass and the like, so I collected my box of brass tubing, and a small .125 bore ball bearing for the cam roller

cutting off the tubing which will be the body of the valve train, to length, squaring both ends.

with a piece of tubing the right i.d. for the bushings, and a small piece of square brass tubing, filed to a fillet for the tube, at an angle putting the end closer to the cam, I'm using a fly tying vise to hold the square tubing while the main tube rests on a graphite square which came out of a water pump which died, and left its body to model engineering. It's a good thermal barrier from the steel table, and cleans off easily, good for soldering on. Everything was cleaned with steel wool before soldering, but my first bit of solder was old and the rosin dried up, so it didn't come out as clean as it should have.

having pressed an .125 pin in the bearing, I'm soldering a piece of tube where the roller goes on the lever arm, the pin to be loctited into the tube later.

Bits and bobs attached to each other, with bushings locktited in the tube, and the roller put in its place, I was going to use the brass channel, but opted for a corner of the brass plate as sturdier, and offering more room for threads.

the brass plate with a tap sized hole in the corner, ready to have the corner cut off on the bandsaw

the cut off corner in a vise, the cut edge being filed straight and cleaning off burrs

rounding off the corner to make it pretty when soldered in place

the triangular piece held in place with some twisted safety wire, ready for soldering to the main tube

having tapped the #0-80 hole in the soldered on brass plate, getting ready to file down the ends of some .062 drill rod to thread for #0-80 for the valve rod, as per the "poppin" set up.

the other end of my tailstock die holder, and the shaft it rides on, fuel pump rod for a Chevy V-8, hardened, mike's out at .500, after a couple hundred thousand miles

threading the first end of the rod

threading the second end, longer, to make enough room for adjusting the valve plate. I had to tighten up my die and get the threads a bit smaller, so everything would fit, now I've got to make some nuts to attach the valve rod to the train, and the valve plate to the end of the rod, and set up a spring to open the valve, so that's the plan for today, and maybe it can be tested when all is done. Thanks for watching, for the advise, and maybe it will run this time around and I can get to the brown stuff, as John wood say. :lol: ta ta for now, mad jack

NickG:
Great work Madjack, am feeling more confident about this now. Can't wait to see more.

Nick

madjackghengis:
Well all, and particularly you, Nick, I've got more pictures to show.

the end of the shop where the brown stuff is piled, this small pile is for the next few days of heat.

having center drilled with a #1 center drill, I then drilled a .050 tapping hole for the #0-80 nuts to be made, drilling the full length of the flutes in both ends of a piece of .250 brass rod, about an inch and a half long, and tapping as deep as the tap will go

drilling and tapping the other end of the brass rod

using a hex 5C collet holder, I set up the brass rod in a .250 collet, with the tap thread length sticking out and a vise stop to set a repeatable placing as I turn the collet holder. I'm taking a total of .100 thousandths off, to end up with .150 hex nuts, in two cuts, .035 followed by .015

taking the second cut on the first end

first end done, deburred, and ready to cut the second end

first cuts on the second end, same numbers

second cuts on the second end, hexes measure out to .150 as desired

using my DRO, setting up to cut off nuts, .100 long for each, with a .045 fin cutting tool

after cutting off the first nut, I can tap deeper and get more thread in the brass rod

tapping deeper to the bottom of the drilled hole, after the third nut was cut off, I'll probably need #0-80 nuts in the future

half a dozen #0-80 nuts ready to be cleaned up, used to lock the valve shaft, threaded already, in place, and to hold the valve to the shaft. I got so excited about getting it in place before dinner call, I didn't take pictures of assembling the valve shaft and valve, but I did get a video, which I am about to download, and see if I can post. It is a running engine now, and ready for some brown stuff to finish off the job. I'm posting this now, as I'm not sure how long the video will take to download, but will post it immediately thereafter. I wish I had gotten some pictures of the valve in place, but you will see it as it operates in the video. :beer: cheers from an ecstatic engineer, watching and listening to my new engine run. :nrocks:

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