Arnold building the "Little Blazer"

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arnoldb:
Thanks Ray!

Thank you David - the smile is even brighter today!

Thanks James; yes it's a Dremel chuck on a home-made arbor. I'll dig up some photos and post it in the tools section in a bit, as it is a really handy piece of kit.

Thank you Dean; I think the powers that be is looking down kindly on my escapades; I'm really having a lot of fun in the shop of late!

Stew, thanks mate; I hope today's post meets expectations!

Thanks Nick - much appreciated!

:beer: Rob; it's all your fault for giving me so much :poke: :poke: in the past mate :lol:

Time to tidy up this one :)

I started with the base, which I decided to make from wood for this engine. A bit of Rhodesian Teak trimmed to rough size with the jigsaw:

Sacrilege! - but the flycutter works a treat in trimming down and cleaning up some wood :

I will really have to invest in some proper woodworking tools at some point!

I used a router bit to pretty up the edges of the block; the mill's top speed is a bit slow for routing bits, but it does get the job done:

Just needs some oil and a good rub-down with floor wax now...

On to a 3/4" to 1/2" copper pipe reducer; trimmed up and tidied up in the lathe:

A bit of scrap HRS turned down to a fairly tight push fit in the 3/4" section of the reducer:

The above was needed so that I could clamp the reducer at an angle in the mill vise without squashing it. I only have 5.5mm diameter pipe for a spout, and no 5.5mm end mill, so I used a 4mm end mill to drill the hole for the spout, and then very carefully followed that with a 5.5mm drill bit. A generous serving of cutting fluid was used; copper is one of the less fun metals to machine:

One of the projects I have on the back-burner is an experimental boiler build - and I learned one good lesson from that; It takes quite a bit more heat to re-melt silver brazing that was already done than to do new brazing. With that in mind, I first silver brazed the spout in the reducer, then cleaned the bottom edge and bottom inside edge of the reducer very well with sandpaper, and made a ring from silver solder that fit in there:

Then I liberally coated around the silver solder ring with flux, being careful not to get any flux on the outside edge. The foot plate is some 1.6mm brass that I just cleaned well with sandpaper.

I just carefully plonked the reducer part down in position on the foot plate, with a lump of steel on top to keep it in position, then let it sit like that for a couple of minutes so that the flux would gravitate down onto the brass foot plate as well, then used a blow torch to heat the lot up, concentrating the heat directly on the joint. After a short while I could see some flux bubbling to the outside as it followed the flame, then it went black and then clear, and a second or so later I could see some silver brazing wicking through. I used the flame right around the entire joint to draw the silver brazing through and let things cool down:

I'll happily admit that this is the best bit of silver brazing I've done to date :dremel:

The tank was then dropped in some citric acid to have a bit of a pickle, and I started on the cap for the tank - a simple turning and knurling job:

Wicking was a bit of a problem; I'd used cotton based wicking on Fred the Loco's burner, but when the meths run out the wicking is inclined to smolder and burn off. Amongst my junk prized collection, I have a sheet of fiberglass mat... Some judicious peeling away of fibers was done, and then all aligned and rolled into a kind of string; a bit fiddly, but I got it fed into the spout in the end:

(Now it had more hair than me :coffee:)

I played barber a bit, and filled the tank with meths; A purple glow quickly appeared at the top of the wick, and I tested it:

Earlier while I was waiting for the meths tank to pickle, I'd also thoroughly oiled and lightly waxed the base, So I assembled the lot, and ended up with this:

A puff of graphite powder into the cylinder, a drop of oil on each of the running bits where needed; and a lot of fiddling with wick position; it's a choosy little bugger - but it runs :ddb: :ddb: :ddb:

The second part of the video was taken in my study; in the shop it was 35C and in my study with air conditioning 26C - It seems to like running in the cooler environment a lot better!

A fun, but challenging little project!

Regards, Arnold

Bogstandard:
Fantastic runner and build sequence Arnold.

I just can't believe how fast those ones run, mine just plods along at a few hundred RPM. Yours almost becomes airbourne.

John

madjackghengis:
Hi Arnold, You've got a fine runner there, it sounds and looks great. I was going to ask the purpose of the solder, as the instructions in the magazine article made no mention of it, and my valve "spring" is a piece of copper about 15 thousandths thick, with a radius on its end fitting in the radius slot in the valve, and it holds fine although you can see the valve plate slide up and down a few thousandths when its running, and I was afraid it would cause a bind, when I saw you soldering the two together, but it obviously works well, and causes no binding or loss of vacuum. You definitely proved out the superiority of iron, for the cylinder, and in keeping with the last video posted, I am going to machine an iron cylinder and replace my aluminum one with it, and put an iron piston in it as well. I just finished boring out my latest ali cylinder about five thousands, turned a graphite piston for it, fitted it all together, and it runs, but barely so, and only for a minute or two, as well as being very finicky about where the flame is. I found out a while back, once it is running up to speed and warmed up, it runs best with the flame as far away as possible, so it can get the hottest part, the top, sucked in, but too far will instantly stop it. Kudos for a fine build, a fine log, and a fine looking and sounding engine. I don't think I've seen anyone's build go as smooth and without hitches as yours has unless you kept all the frustrations bottled up inside, and didn't share them with the rest of us :poke: Great Job, and I hope mine runs as well with a better set of bits and pieces. :bang: mad jack

arnoldb:
Thank you John - much more than just for your compliment. I'd like to count myself very gratefully as one of the newbies who has learned a great deal from what you and other experienced machinists/builders have shared!

Thanks Mad Jack. Yes, it is finicky about where the flame is; I had a look, and it runs best when it is sucking a nice blue bit of flame into the piston. Setting the valve was fairly easy; I just tensioned the valve spring plate so that it barely holds the valve against the face, and also manipulated things that the valve is very flat against the face. I didn't spend all that time flat-lapping for nothing ;)

Kind regards, Arnold

Bogstandard:
Arnold,

Only a couple or three years ago, people were having all sorts of trouble getting these flame lickers running, and because of that, at that time, not many were ever built, and a lot of those that were, got thrown under the bench in frustration at getting them to run.

By everyone sharing their info about such things, it seems that anyone who builds one now can get the knowall to make a running engine.

Only by sharing, mistakes and all, does everyone become a winner.

John

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