my attempt at Rupnows imperialized ridders flame eater

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werowance

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so I wanted to try to make my second engine, I am still learning a lot and am sure I will make plenty of mistakes, (already have). I decided to try Brian Rupnows imperialized plans for Jan Ridders Flame eater since I dont have hardly any metric cutters or drills.

so to start with I found a piece of scrap aluminum to cut the base out of. it was free but had been bandsaw cut on all 4 edges so I had fun squaring it up. came out nice and the holes drilled and tapped just fine

I also want to thank Brian for answering all my stupid questions. hes been a great help to me so far

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Next I took some more scrap aluminum and glued 2 plates of the proper thickness together with locktite, allowed to dry over night and then started milling and drilling to shape. my last project of a pair of kant twist clamps came in very handy to keep then held together. I wanted them cut in a pair so that the bearing holes would be drilled and reamed together. I guess you would call it a line bore? at any rate that came out very well in my opinion. took a little pencil torch to break the locktite bond and they came out in a pair just like I wanted. also the bearing holes I couldn't have asked for better. they are a press fit but not extremely tight. I had to heat the aluminum just a little and had the bearings in the freezer for about 15 mins. I was able to push them in by hand fairly easy and once they came back to room temp they were held in place tight and would not budge. but not so tight as to deform the bearings.

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next would be the thing that fooled me the most. the fly wheel. I really thought it would be the funnest part of the build and easiest. turns out so far to be the most agrivating. its my first time cutting bronze and this stuff is gummy like cutting copper. it wants to dig in and pull and the edges want to roll out. but this log of bronze was dirt cheap on ebay and I have a lot of it.

so after cutting off a slice of it in the bandsaw, I chucked it up on the out side and cut about half the wheel on the lathe. also center drilled it. leaving the outside slightly large and the inside cuts slightly small.

to make the center hole exactly the right size for the crank shaft, I made a dbit out of some of the same rod I cut for the crankshaft (forgot to make pics of the crankshaft build)
I chucked that in the lathe and used a little emory cloth to smothe down the shaft and to also make it ever so slightly smaller so the reamed hole hopefully would be a good tight but still sliding fit.
and that's what I got. I could push the crank shaft in but had to give it a little twist with light preasure to get it on the shaft.

after that I turned it around and faced the other side and brought down the outside lip a little closer. but I just could not hold it in my 3 jaw because I didn't have enough material. so I made an arbor to hold it and switched to my er32 chuck. just doing all this took me forever.

once I had both faces cut properly and then I brought down the outside the correct dimension. left it on the arbor and transferred it to a er32 mounted on my rotary table. from there I drilled all the holes and then stood the table on its side and drilled / tapped the set screw holes.

all of this took me at least 2 weeks. (that's night funtime in the garage 2 weeks-not a full time job 2weeks)

glad that parts over with

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I used a piece of old hydraulic ram shaft to make the cylinder supports from. this stuff cuts pretty easily. I figured it would be hard as a rock but actually I think it was better than regular cold roled steel.

not many pics of that but you will see the final product in my next post with all the parts I have so far assembled.

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and last, some pictures of all I have made so far. I didn't have any pics of the crank shaft, but its made from left over rods from a printer / scanner. not sure of the steel alloy they are but cut easily. the crank face or throw or whatever its called was a piece of 12L14. I was worried about silver soldering to it but the 2 pieces solderd up just fine.

after assembled I have it the spin test - Ridders suggests I think 2 min of free spin as a test of the fly wheel. I came in just short of that 1min 58 seconds. I'm thinking a little more spinning will free it up even more I hope

this is about a months work for me so far so its looking like maybe next Christmas I will have an engine lol.

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not much progress. having some hvac issues at home so very little fun garage time. but I cut a piece of 303 stainless, faced both ends and barely cut the skin off of it last night. I thought 303 was supposed to be easy machining stainless. this is pretty darn hard. took no time to smoke the cutting fluid using carbide to cut it. guess I need to slow the chuck speed down some? feed rate is very slow.

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Just a little tip---The engine I built has a 316 SS cylinder. I find that it is just horrible to get it to run. There is a great difference in the thermal conductivity of stainless steel and cast iron. I think perhaps my engine would have ran better with a cast iron cylinder. I have never had a great deal of luck with Jan Ridders designs. They seem to work just fine for him, as he has videos posted of them running. I however have a difficult time getting consistent runners when I build his designs.---Brian
 
not much done so far got it drilled and bored out. tried using my carbide boring tool but it was to flexi and lots of chatter so switched to a homemade 1/2 inch boring bar. basicly a pice of 1/2 drill rod with a angled cross drill at the end with a set screw in the tip. the cutting tool is a broken high speed drill ground to shape. no pictures of that tool.
I'm up to cutting the cooling fins. that's not been fun. my parting tool isn't as wide as the drawing called for, the drawings said the size was typical so I could have made it slightly different and I wish I had because trying to shave off .014 of the edge of a parting cut makes the carbide insert deflect a lot. ill have a lot of file work to get these in better shape.

and then last, the paper towel sticking out the end is the dumbest thing I have done so far. after I bored it, I said wonder if my brake hone will actually fit in this bore. well it did, so I said lets see what one or 2 passes look like while its there. well it went thru the other end and expanded. now I cant get it out until i am ready to unchuck it. grrrrrr. what an idiot i am. so the paper towel is stuffed in there to keep it from flopping around until unchuck time.

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finished the fins, and parted it off last night. now to make an arbor for it and get it on the rotary table.
and while I'm thinking about it, laps - I have made a few from brass and understand how they work. but brass is expensive, aluminum I would think might be to soft and I was thinking I have some 12L14 leaded steel laying around close to size. what about a lap made of it? its definitely softer than the stainless the cylinder is made of. do you think it will be still to hard to expand properly or it might scratch things up to much?

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Following along this build ��
 
not much accomplished in the garage this weekend. tilled, mowed, mulched. great spring weather Saturday. even got a little sunburned. and then back to freezing temps last night.

got the cylinder almost finished honing, will do that last bit after I cut the intake slot in it to help debur it. almost finished the arbor to put it on my rotary table. I hope to have that done tonight. then fun times for me trying to square up the rotary table. that will likely take me an hour or more. I have yet to achieve that trained eye that some seem to have who can sit a vice or rotary table on the slide and have it almost perfect just by eyeballing it. I'm a little tap on this side, then another tap on the other and repeat over and over.
 
Does you rotary table not have the key-slots in the bottom? Any rotary table I've seen has. You simply make a stepped key, half of which into the rotary table base and half of what fits into the slot in your milling table. Use a counterbored shcs to hold the key into the rotary table base permanently. Then you have instant alignment every time you set the rotary table on your mill.
 
it does for verticle (rotary table laying on its back flat with face pointing up but not horizontal.
and on the verticle it only has a place for 1 key on 1 end of it thus it still wiggles to much. I will double check that tonight to make sure its not just missing a key. but if memory serves there is only 1 place. and on vertical also, there is only 1 bolt hole to mount it down which annoys me as well, horizontal you have 2 holes 1 on each side.

I wish it were like my compound for my lathe bits. keyed on both ends.
 
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