# Interesting flame licker



## Alex (Jul 17, 2007)

It has a really interesting valve design.


www.heetgasmodelbouw.ridders.nu/Webpaginas/pagina_happer_inw_schuif/inw_schuif_frameset.htm


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## rake60 (Jul 17, 2007)

I built that engine with an aluminum cylinder and could not get it to run.
Just yesterday I was able to get my hands on a cast iron bar end to try
it again using the correct material.  So far all I have done is the 
cylinder.  It's still needs some cleaning up.  This picture was fresh off
the mini-mill.





It will be some time before it's done.


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## Alex (Jul 17, 2007)

Looking good. Interesting to see it run later, I'm sure it will.


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## BMyers (Aug 5, 2007)

Rake,
I started on the same one today, this is my first venture into flame lickers. Do you lap the bore ? How close do you fit the piston to the cylinder ?


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## rake60 (Aug 5, 2007)

I cut the piston for a snug but movable fit to the cylinder, then coated the
cylinder bore with plain toothpaste to act as a lapping compound and 
worked the piston through until it had a free sliding fit.

As I said this was my second attempt at this design.
When I was taking the original model apart I somehow damaged one of
the ball bearings.  It's on hold until my next shopping spree to the hobby
shop...


I'm still trying to make a running version!


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## Alex (Aug 6, 2007)

It'll be interesting to follow the progress of your engines. Don't forget to take pictures.


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## shred (Aug 6, 2007)

Anybody tried a 2-cylinder flame licker, a-la Dos Pyros (http://www.stirlingsouth.com/richard/DosPyros.htm)?  They say a lot of the low power, tough-starting issues are solved with that.  I've toyed with the idea of making a horizontally-opposed 2-cyl version, but never got much beyond thinking about it.


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## Bogstandard (Aug 8, 2007)

Hi Rick,
How did you drill the 2" long 2mm hole in the side, all my 2mm drills are exactly 2" long so nowhere to hold onto. I suppose I could silver solder an extension on and take it very gently.
I have been looking at this design for a while now but never having built one I was a bit dubious of starting it.
Then Shred put the link to Dos Pyros, et voila!, why not make a twin cylinder version to see if it would run better.
So did all the calcs last night, saw what bearings I've got in my stash. a quickie call to a friend who works nights to get a lump of something heavy for the flywheel. 7:30 this morning 3 lumps of bar end in what looks like stainless but 50% heavier were delivered, 2 pieces to learn how to machine it, the last to make the flywheel. Nice having friends in the aerospace industry. Just got to hack some cast iron out of sash weights and we are away. If it doesn't run, very little lost, salvage what I can and do something else, not the end of the world.
All I have to do is decide whether to have the cranks at 180deg or 90degs apart, any comments would be useful.
Will start it next week after finishing rebuilding my piston valve engine.

John


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## rake60 (Aug 8, 2007)

I used a #47 bit.  It's .0785" or 1.9939MM 
I drilled as far as I could with the bit chucked properly then extended it 
out to where I was just barely catching it in the chuck to finish the hole 
through.  It just made it through, but cast iron drills freely and the full 
length of the hole is supporting the bit.


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## Bogstandard (Aug 8, 2007)

Many thanks Rick,
I will be drilling in the miller, I will see how I get on, but I think I will keep the silver solder on the horizon, just in case I bottle out.
The main problem being in the UK is that kids nowadays aren't taught the old imperial system, and metric is starting to get a strong foothold, so I have to work in three different types of drill sizes, fractional inches, numbers and letters plus metric, very confusing at times, so if I start to drift towards metric, let me know and I will try to moderate my Eurolanguage.

John


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## rake60 (Aug 8, 2007)

My company works internationally.
I see German prints that the only thing I can understand are the numbers
(divided by 25.4)  :wink:   My model size taps and dies are all metric and
the local suppliers are stocking the metric hardware to support that.
My micrometers and calipers are still Imperial but I have a feeling that 
my grandson's will be metric.


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## tattoomike68 (Aug 8, 2007)

I am fine with metric or imperial, I use vernier calipers that read both directly.

5/16" (.3125) is just a butt-hair under 8 MM  (.315) A few sizes are close enough for the gals we go out with.  :wink:


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## Bogstandard (Aug 12, 2007)

Rick,
Drills were too short, couldn't get thru the last 8mm piece, so ended up silver soldering 1" extension on, worked a treat, both cylinders drilled, just got the boring to do.
How is yours going on?

John


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## rake60 (Aug 12, 2007)

Mine is still pieces in a box on the holding shelf.
I need to get back to it soon.  I still haven't bought the replacement 
bearings I need for it.
So many plans and so little time...


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## Bogstandard (Aug 12, 2007)

I know exactly how you feel, I still need a couple more engines to put on a display in about four weeks.
My problem in the past is that I have given all my engines away, so now I've got nothing to show.
So I am hoping this licker I am building will be working by midweek and then I think I will build a smallish turbine for something a bit different, no plans, but who cares, just build something and hope it works.

John


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## Bogstandard (Aug 13, 2007)

I can see a couple of techie solutions coming on, not just for this engine but can be used elsewhere.
This engine calls for a couple of bits of 2mm rod to be silver soldered together at right angles. This is how I did it using a strip of plate and a couple of small magnets.







The joint already has a loop of solder wire draped on it, just a bit of flux and heat and the job was done.






Sorry about the quality of the pics, until I have had my tenth cup of coffee the world is a blur.
The next one is about how I produce an accurate cylinder bore, especially this one as I am making a matched pair. Up to 14mm I would just wack a machine reamer thru it and call it job done, but these had to be bored. On these I drilled a 16mm thru hole and finished off all other jobs on the cylinder, the boring is the last operation, just in case the other ops distort the material
Before I do anything I will make a go/no go gauge out of brass, turned to 0.001" undersize, then on the end 1/2" I will remove a further 0.004", this is the "go" part. Bore out until the "go" part just fits in the bore and the "no go" won't. This is the time for very fine boring and continual checking until the 'no go" just fits into the bore. Then swap them over in the chuck, turn the speed down to the slowest on your machine and use the gauge as a lap to true up the bore, I use my own home made diamond lapping paste on cast iron but the fine lapping paste used for grinding in engine valves will do (do not use diamond on soft bores such as brass and aluminium). Using this method both of these bores are within 0.0005" of each other and there is no detectable taper.






This is just to get the bores true and parallel, the pistons are machined to fit the bore and later lapped to the bore to get a perfect fit.

John


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## shred (Aug 13, 2007)

I find hundreds of uses for good magnets in the shop.  If you know somewhere to get old PC hard drives from, they usually contain a couple very very strong magnets (as well as some nice bearings and parts) inside.


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## Bogstandard (Aug 15, 2007)

I will just explain a comment that I made in my last post about not using diamond lapping paste in soft cylinders.
Diamond lapping paste is now becoming readily available and people are thinking it will solve all their lapping problems, nothing could be further from the truth. It is fine with hard cylinder bores and soft laps but not with soft bores like plastics, brass or aluminium.
Normal grinding paste actually breaks down into smaller pieces as it is being used and can usually be washed off the finished bores with no problem.
With diamond lapping paste the diamonds embed themselves into the lapping faces, if you look at the brass bar that I used you will see the small diamond bits embedded in the surface, but because the lap is softer than the bore it will only embed itself into the brass, so effectively turning the brass into a very accurate round diamond file. In fact I will start off by embedding the diamond into the soft lap by forcing the paste into the surface with a piece of hardwood. I will reuse this lapping bar again by just turning off the old diamond finish.
So basically the diamonds will embed themselves into the soft wall cylinders and continue to act as abrasives thru the life of the engine and will cause premature failure.

John


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## gilessim (Aug 19, 2007)

How would one go about cutting that groove on the cam of dos pyros without c.n.c.?


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## Bogstandard (Aug 19, 2007)

Giles,
I have never seen it done or ever attempted anything like that, but rest assured grooves like that have been around since at least the mid 1800's, maybe a lot earlier, and I don't think they resorted to a CNC machine.
If it can be drawn, there is most probably a machinist artisan somewhere that can make it manually, and do it in his sleep.
Many years ago I was involved in the development of the first 3 1/2" linear reading hard drive, called 'The Penny', with a massive 47mb capacity. The chap who made all the parts for this is my good friend, and he is one of these people who can look at a problem and find a way to make it by hand. He comes in very handy when I hit a problem with my machining.

John


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## BMyers (Sep 19, 2007)

Here is my progress so far, I dont like the burner, so I think I will design my own


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## Bogstandard (Sep 19, 2007)

You have done a wonderful job on that. Very well engineered.
When I built mine as an experimental platform I found that the burner position as shown on the drawings just would not work with any reliabilty.
Before you go into making a new design burner have a look at my posts on this engine, even the designer recognises that my position of the burner is more efficient.
Lots of luck getting it to run.

John


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## Cedge (Sep 19, 2007)

John
The diamond lapping compound comments are well heeded. Oddly, a friend and fellow collector and I were discussing the need to lap the cylinders of my current project and he sent me a link to an interesting source for lapping compounds.  The product is called "TimeSaver Lapping Compound" and comes in a numbe rof grades. It is made to degrade during the lapping process, becoming a polish and then an inert non abrasive material.  Supposedly it allows for lapping without worrying about having to chase stray bits of grit when the job is done. 

You can read all about it at http://www.newmantools.com/lapping/time.htm . It appears that it might have some interesting potential for hobby use. 

Steve


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## Bogstandard (Sep 19, 2007)

Steve,
That looks like a good product, if it does all it claims.
The test kit sounds a good idea, the quantities that we use that should last a lifetime. Shame it is not available in the UK otherwise I would try some.
I have used something similar, and that I think had a bicarbonate of soda base, but it was only used for very fine lapping and washed away with water.
No prices shown though.

John


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## Bogstandard (Sep 20, 2007)

Hi Ian,
I have contacted Jan over the last week or two and found him very helpful, he explained to me the total working of the flame licker and put my mind to rest as I was getting very unexpected results.
A very knowledgeable man. He will be a great asset to understanding how these engines work.


John


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## BMyers (Feb 17, 2008)

Is it possible to have too much flame for these engines to run ? Is too much heat as much an issue as too little?


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## Powder keg (Feb 17, 2008)

I've not built this engine. But, on the fire eater I built, more fire makes it run faster. If you are having troubles make sure everything is friction free. The new piston I made is .0005 looser than I wanted and it runs great! If i remember right, the timing is better Retarded?

Good luck, Wes


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## Lew Hartswick (Feb 18, 2008)

OK so we have 2 cyl opposed and a 2cyl inline. Anyone for a flat 4? 
  ...lew...


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## bentprop (Mar 7, 2008)

I built this engine too,but couldn't get it to run.I have a feeling the contra piston in mine is a bit loose.I'll get a roundtuit one day,and make a new piston.I used cast iron for the pistons in a steel cylinder.


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## rake60 (Mar 7, 2008)

Welcome to HMEM bentprop.

I've built that engine twice now over the past 2 years.
Neither one of them has ever run. : 

I'll keep trying at mine and best of luck to you with your own.

Rick


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## Bogstandard (Mar 7, 2008)

Bentprop,
I think your statement has solved the problem for you.

This engine relies on the carbon content of the cast iron cylinder and pistons for its lubrication and running qualities. Also the bores need to be lapped to a glass like finish and the pistons slide thru like silk.

Lew,

When eventually I get a bit of time, I already have plans for a four or six cylinder boxer configuration engine. The stumbling block is the method of heat input to the engines and getting it the same to each cylinder. I managed to get the twin running by critical placement of the meths burners, but this would be almost impossible to achieve using more cylinders. I have the plans for a micro bunsen burner system and hope to develop it to give repeatable output for each cylinder. 

John

Two links to my twin build

http://www.homemodelenginemachinist.com/index.php?topic=212.0

http://www.homemodelenginemachinist.com/index.php?topic=350.0

It might answer a few questions for you.


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## gilessim (Mar 8, 2008)

I've nearly finished one of these and I'm having some doubts because I used SS for the pistons and cast iron for the cylinder , I only had an 8" length of 35mm cast iron to start and it seemed a shame to cut it down for the pistons ,I had 2 go's at them but now they are a nice gas tight fit ,they both move together with the suction ,any ideas that this will work or not with the heat?

Giles


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## Bogstandard (Mar 8, 2008)

Giles,
The only way is to suck it and see.
Jan was fairly clear about using the right materials for building his engines, because of the different expansion rates. I don't know what the difference is between the two materials you have used, but maybe expect a bit of trouble.

Don't forget to warm up the cylinder first, I use a blowtorch for 30 secs. Otherwise you will spend ages trying to get it going by the heat being transferred thru from the burner.
That is the most frustrating time, trying to get the burner in the right position.

John


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