First Engine Build - A Flamelicker

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Cogsy

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Location
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Being that I'll probably never build anything spectacular enough to do a proper build log, I thought I'd share my very first attempt at machining, to show other newbies some idea of the process I went through.

I'm building Jan Ridder's Flamelicker with internal valve, mainly to the plan, but with a few little changes to make up for my lack of skills.

First I machined a 40mm aluminium bar to 38mm O.D. and cut the cooling fins. This was my first go at machining and turned out better than I expected. The instructions call for stainless steel for the cylinder, but the plans say aluminium, so I went with the easier option.

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Then it was bored out to just over 22mm (it was supposed to be exactly 22 but I overshot a little :Doh:).

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Once I'd parted it off, reversed it and faced the other end, it was onto the bench for a photo shoot so I could post a pic of my first part :D

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Too scared to attempt the milling required on my cylinder, I started on the legs for it instead. This was my first go at machining brass and I was pleasantly surprised at how well it machines. In no time at all I had a large pile of very expensive dust :).

After junking the first pair of legs because they looked nothing like a 'pair', I decided to be a bit more methodical.

I turned the bar down to the major diameter of the legs (18mm), then worked out where the first shoulder would be and turned a small area down to slightly over the next dimension.

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Then I turned the rest of the step down and finished it all at the proper size, then repeated for the final 2 steps.

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Once I'd single-point-threaded the end (scary stuff but it worked out ok), I measured it up and parted it off. I couldn't believe how thin the piece went before it actually parted.

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Then I repeated the whole procedure as close as I could, and ended up with two legs that look reasonably similar to each other.

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Once I drilled and tapped the bottom of them, they became my first completely finished parts.
 
Thm:

I am very much enjoying this. You're doing a great job! I am going to follow this thread with a great deal of interest. It is providing me with some great encouragement, because I am totally new to all this too. I really appreciate you posting this up.
 
Looking good Cogsy! If that is your first effort at machining, then you will have a lot to teach the rest of us very soon. Please do keep the build log going.
 
Nice work Cogsy,keep it up mate and enjoy this great hobby.

Best wishes ,Ian (seagar)
Arrawarra.N.S.W.
 
Keep going Cogsy, it looks nice.....I am not any better than you are.

Mario
 
Thanks for the encouraging words everyone. I'm actually a fair bit further in this build than with the log, and I can assure you the quality of construction dips a bit. But I vow to finish this thing!

Next up I 'bit the bullet' and used my mill for the first time to mill flats for the legs and the flat area and slot for the flame to enter. It was very stressful so I didn't manage to take any photos while I was doing it. It will be good enough to work but I made a few errors. I also drilled the 3mm hole for the valve rod at the same time. I had to make small collars for the legs as I didn't drill the holes in the cylinder deep enough.

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Then I whipped up the clevis for the power piston and the pin for the valve out of brass. This was a fun little job, working with 3 & 4mm diameters. The pin for the clevis is steel turned down to 2mm.

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Next I decided to make the valve actuator plate. This is a small collar of brass soldered onto appropriately shaped 1mm brass plate. My soldering skills are lacking and it proved a more difficult job than I imagined.

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I don't want these posts getting too long so I'll split them up a bit.
 
Looking good Cogsy. I pulled a chair and will be following you along.

Vince
 
Next up was a job that I needed much help from the forum with. I needed 66mm of 5mm steel rod turned down to 3mm. After much advice, I used the method hanging 15mm sections out of the chuck, turning that down, then extending the rod another 15mm and repeating. I didn't think about ensuring I didn't rotate the rod in the chuck as I moved it, so I had issues with runout errors. At 45mm long, the rod was getting quite a wobble up, so I reversed it and started from the other end. This method wasn't ideal, but I did get a useable part in the end. Next time I need to do something similar I hope to have a collet chuck (or maybe just source some 3mm rod :p).

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Once the rod was finished, I managed to solder the valve actuator plate onto it - backwards as it turns out :-[. I fixed it once I realised, but lesson learnt - Check The Plans!

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The part for the other end of the valve rod is designed very similar to the valve end, with a grub screwed collar soldered onto 1mm shaped plate and with a small piece of 2mm rod soldered on as well. I made the pieces without much trouble, but I couldn't get them soldered together for the life of me. I could get 2 pieces together, but they'd de-solder and fall apart when I was doing the next one. Eventually I heaved them over my shoulder and came up with a collar/plate assembly turned from 1 piece of brass then filed to shape. Then I drilled it and made a tight fitting 2mm rod, which I then Loctited in place. Take that soldering skills!

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Next episode will be the crankshaft - where things really start to look dodgy...
 
I didn't have a suitable piece of steel for the crankshaft, so I grabbed a piece of mystery metal from the local scrap yard. In hindsight I wish I'd sourced a proper, known, easy to machine grade...

It started out 38mm in diameter, with the shaft needing to be 8mm. Turning it down was a very long process. It didn't machine well at all. Seemed to be very hard to cut and the surface finish is terrible. Here's the main shaft with a bearing test fitted. This is something like 2 hours of machining and sanding/polishing to this point. Notice the horrible finish on the larger diameter.

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My band saw lacks precision (it can cut awesome unexpected curves), so I hacksawed and filed the crankdisc to shape. At this point, the plans call for a small brass spacer to be soldered into a hole in the crankdisc, then drilled and tapped for an M2x0.4 thread, for the big-end pin to screw into. Now we all know I can't solder, and I haven't got the tooling or capability to make an M2 thread. What I did instead was drill and tap an M3x0.5 thread in the crankdisc, then machine a spacer with a 3mm bore and finally make a threaded big-end pin with an M3x0.5 thread to screw into the crank. This part turned out well, but the actual crank looks quite shonky.

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Next up - finally received my graphite for the piston and valve.
 
I got my graphite off ebay and it was described as a 'stirring rod' for metal casting. I don't know if it's the usual grade for machining, but it was only $25 delivered half-way round the world for a 1"x12" rod so I took a chance. It seems to do the job.

Here it is set up ready to go. The black plastic tube is my shop vac, which I ran the whole time I was machining it (quite a bit closer to the work piece than in this photo). I also wore a dust mask as I expected huge clouds of black dust to fill the air, but in reality it wasn't too bad. Any particles that were too heavy for the shop vac to grab just settled on the lathe bed and I vacuumed them up later. My hands turned black but everything else stayed pretty clean (including the white dust mask).

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I couldn't take any in-progress shots as my hands were way too dirty, but here's the completed piston and valve. Notice where the graphite snaps as it's parted off. This happened with all 6 pieces I ended up making.

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Here's a couple of fluff shots of them in the bore, together with the hand-filed conrod I made from scrap 2mm aluminium and forgot to photograph...

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If anyone is interested, I discovered a few things about this type of graphite. For starters, it machines beautifully. I could take massive cuts or tiny cuts and the surface finish was always the same - a smooth, dull grey. As I mentioned, when parting it off, the centre snaps off, always below the face of the part. Perhaps hacksawing would be better if face finish is important.
It's the absolute easiest stuff to tap you will ever come across, and it holds the threads well, but they are fairly easy to strip or pull out completely if you apply too much force on the bolt.
Most interestingly, it seems slightly compressible. The plans say the piston fit should be no more than 0.03mm less than the bore, so I finished the first set 0.01mm larger than the bore and forced them through until the fit was good. As I did that, they took on a noticeable shine that I assume was some sort of compressing/hardening of the surface. After buggering up that set later on, I made another set, this time stopping at 0.03mm oversize. With the rod still in the lathe, I worked the cylinder onto the rod (with much difficulty) and reamed it back and forth as it freed up. All the while being ridiculed by my wife who had come in to drop off a coffee for me and found my actions somewhat comical. Although the fit freed up considerably, it was still too tight, so I measured the bar again. Shockingly, it was still 0.01mm OVERSIZE! I measured in different spots, I remeasured my bore and still the rod should not have been able to fit in the cylinder. The only answer is that it was compressing as it passed through the cylinder. After buggering up that set a short while later (too much force on the threads :wall:) I made a third set. This time I stopped at 0.01mm oversize again and the lapping procedure was much quicker and produced an excellent fit to the bore.
Long story a little bit longer, it's weird stuff to work with but not difficult and makes excellent pistons.

Next will be the dreaded flywheel...
 
Cogsy - seriously I am really impressed. You mention what a pain that mystery metal for the crank is, but boy you ended up with a really good looking component. That's the sort of thing that frustrates the living heck out of me. This engine is coming on great - big thumbs up from me. I really dig your insights on machining these materials too.
 
Thanks for the very kind words Propforward. I think my pictures are a little biased though, that crank looks a lot worse in the flesh. The shaft is good, but the disc has deep 'witness marks' in it. Overall though, the whole thing is turning out better than I had dared hope, and I still plan a bit more polishing.
 
The biggest piece of brass bar I could get hold of measured out at 63mm and the flywheel was supposed to be 64mm, but I figured that would be close enough (in Aussie speak it's "she'll be right"). I hacksawed off a piece and ended up with a curve that my bandsaw would have been proud of - nearly 10mm! So an hour or so of 0.005" facing cuts, then a very light skim of the diameter and I was ready to start.

I got it bored without an issue and turned the spigot in the middle that sticks out past the rim, but I had major problems trying to turn the inner diameter. Using a combination of normal and reverse turning I got something approximately like it was supposed to be. Then I wrapped it in masking tape to protect the finish from the jaws of the chuck, turned it around and faced off the excess thickness. Again the inside diameter was extremely difficult for me to cut effectively, but I did get it done. Once it was finished and I could compare both sides, I was disappointed to see just how different they are from each other. Just as well no-one can look at both sides at once :p.

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To lock the flywheel to the crank there is a 45 degree hole in the middle spigot, threaded M3x0.5, which I assume a grub screw goes in, although the plans don't show a screw. I had to do a bit of googling to work out how to drill at an angle. Because the rim of the flywheel is in the way to start the hole straight and then angle it, I had to make a little jig. Basically, I drilled the appropriate sized hole straight through a piece of 12mm aluminium, then filed the piece to 45 degrees and sized it to fit in the right place on the spigot. Some carefully placed tape held it in place and I mounted the whole thing on the right angle in my drill press. The jig acted as a drill guide and the hole turned out almost exactly where I wanted it. Maybe an endmill would have worked without a guide (I don't know that it would) but I didn't have the right size anyway.

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I originally made a grub screw out of brass, but it can't stick out of the flywheel very much, so it can't have a head on it. At 3mm diameter, the slot I cut for a screwdriver wanted to just snap out all the time, so I remade it in steel instead. I also ground a small flat/groove in the crank where the grub screw contacts, making it much easier to lock the flywheel and reducing the amount of force required on the grub screw threads.

Here's a picture of the flywheel test fitted on the crank, with the bearing posts that I hacksawed, milled and filed without even thinking about taking photos of (milling really stresses me out and I forget about everything else).

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It's getting very close now. I needed to start thinking about a base to mount it on, and a little hunting turned up an old jarrah board that has been laying around outside the shed for the last few years. It doesn't look much in the pic, but I was sure there was an acceptable base lurking inside it.

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I cut the split end off, planed it flat (it was bowed side to side) and hit it with the belt sander. Then a bit of a chamfer, some hand sanding and now I'm waiting for the clear varnish to dry. It looks very different, but I'll wait to post the finished pics til there's an engine bolted to it.

The last piece I had to make was the burner. The plans show a rectangular brass burner which I assume is milled and soldered. Well my mill is out of action til I get a new drawbar and we all know about my soldering skills, so I had to come up with an alternate plan.

I decided a round burner, bored from some 1-1/4" brass would be perfect. Then I turned a lid to suit and bored an 8mm hole through the lid, off to one side.

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Then I drilled a 3/8" brass rod to just under 7mm, and turned the O.D. down to make a tight fit in the lid, for a wick holder. I've made a wick from cotton balls and it seems that it'll work just fine.

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Now it's just a matter of cleaning up the parts as much as possible while I wait for the varnish to dry on the base, then assemble the engine. I'm hoping to be able to post some completed pics tonight :D.

Thanks again for all the words of encouragement along the way.
 
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The varnish dried and my fingers got too sore to polish parts anymore, so I bolted all the bits and pieces together.

It sure was a nice feeling to step back and admire my handiwork for the first time. Without further ado - here's the first pics.

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The wood for the base turned out a treat if I do say so myself, although the whole thing looks better in the flesh than my dodgy photos.

In case you're wondering - Yes, it does run woohoo1. Probably not as good as it is supposed to, but I'm super happy that it runs at all. I'm uploading a video to Youtube now and I'll post it in the 'Finished Projects' area. Technically it's not 100% done - I still need to put felt on the bottom of the base, replace the tacky screws with proper bolts on the bearing pedestals and mill the holes in the flywheel, but I really want to show it now in case I break it.

Thanks yet again for the support guys! Thm:

Cheers,
 
Wow that looks beautiful. Congratulations on getting it running. That was my first engine also, and the only one I gave up on getting running. Maybe I will play with it again, you have inspired me!

Lee
 
Congratulations that is a very nice looking engine and thanks for sharing your build,I really enjoyed following it.

Ian (seagar)
 

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