Finger engine revisited

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Bogstandard said:
Will the masked man get it done?, or will he fail dismally?,

No problem imho ......... t'will be complete with a day to spare methinks ;)

Very nice work John :)

Dave
 
Dave,

Making them is the easy bit, finishing them off will take the time. I am expecting at least 6 hours finishing work for the baseplates alone, so a bit tighter than you expect.

John
 
John... I really enjoy the retro styling you are doing with these engines. Guru or not (yes to the guru... and don't argue with me!) you do fantastic job of documentation and THAT is appreciated on this board. It gives others ideas on how to do things. Especially us newbs. And for that, Thank You John.

Eric
 
Remember, you reap what you sow. What you put into the lives of others comes back into your own.

Eric, if you learn just one new thing out of the whole post that helps you on your way, satisfaction is guaranteed on my part.

Early start today, got rid of the wife for the morning, stuck the dog into his box with superglue, and put anti personnel mines at the front of the house. NO ONE DISTURBS ME TODAY. Next stop, lunch.

John

 
Bogstandard said:
Not much of a secret really, a cheap and nasty set of carpenters drum sanders. I mount them so that there is a gap of about 1/32" between it and the drill table. I find I can profile all non ferrous stuff in no time, and keep the sides totally square. I usually have a bit of 1/16" plate under the part to get it away from the gap at the bottom. I have been using these for years, and this drum has never been changed yet.

John,

You've thought of this already and there is a very good reason why you don't I'm sure ;D

If you were to put a hole in your 1/16" plate the diameter of the sanding drum, the gap could be submerged and the full periphery of the drum would be available without having to move the plate.

Al

 
Al,

I knew there must have been a better way.

Thanks for that.

I do in fact use four different sizes of drums, so the way I do it is just easier for me. But yours is definitely a better way if just using one size.

John
 
After an early start today, and finished at 9 tonight I am whacked out. Something didn't go quite right, so that held me up for about three hours while I put the bases right. I was forced to do a little bit of climb milling (not recommended) and the cutter jumped out of its slot, so a redesign was called for, the base is now 1/4" narrower than I had planned.

So what really got done?

First thing was that I took the brass out of the pickle and did a polish job on them. Still not quite finished, but can't go any further until the standards and conrods are mounted.

finger2bits16.jpg



I would have liked to have had a wooden base to these engines, with a thin mounting ali plate. But because of time limitations I have gone for 1/2" thick ali plate, again recycled from old factory jig plates. This pic shows the 'brick' of three plates stuck together with double sided tape and has already been squared up. These were then profiled to shape as a block.

finger2bits17.jpg



After they were shaped up, I warmed them up with a blowtorch and left them for five minutes, this allowed them to be split apart fairly easily, and peel the old tape off. As you can see, the bases still have a bad surface finish, from being used for years in a factory.

finger2bits18.jpg



Now starting to look like a finger engine. The bases were flycut on both sides to clean them up, and the mounting holes and counterbores drilled.
The bases still look too bulky, but by putting profiles on the edges will give the illusion of being thinner and lighter.

finger2bits19.jpg


So tomorrow will be to profile, polish and engine turn the bases. Make the conrods (still have no idea what I want them to look like), flat and polish all the bits, and start putting them together to see if they run.

John
 
A quick blast now, earlier than usual. I will be working on these until the early hours to get them completed, but won't be able to post the finished results until late tomorrow, as I have a motorcycle to prepare for a display, with a friend.

So here goes

The crappy and scratched blocks from my last post have been profiled to give a 50/60's look (remember the cinemas from that day, outside they had straight lines and nice clean curves), cleaned up and polished. The top faces will have to be flatted by hand to get a good finish for engine turning.

finger2bits20.jpg



This shot shows how I dress my hard rubber abrasives to give the correct size that I want. They are being taken down to 1/2" from 13mm, that makes it easier for me to layout the engine turning. I am abrading them down on a standard grindstone dressing stick.

finger2bits21.jpg



Two hours, and two bases completed, just one more, a bit of dressing and polishing on the other bits will start to see things coming together and the engines should be finished early in the morning.

finger2bits22.jpg


These WILL be done for tomorrow, so no worries on that score.

John
 
John,

I really like the profiling on the bases :) and the engine turning (which is soon to be tried!) really makes a huge difference. But then you already know that!!

The recipients of the final engines should be gobsmacked! ;)

Can't wait to see the finished article.


Ralph.
 
Sir
Your finger engines are the greatest. I hope to try some soon. I look forward to your updates and pics. Can you give me or include in your posts some of the steps to achieving the finish polished loook of the al and brass. Keep up the good work.

Rick
 
Just got back in, a hard day getting a motorcycle ready, everything up and running.

Unlike my finger engines. Got to 1am Friday morning, starting to assemble, picked up the flywheels and noticed that they were absolutely filthy where they had been bead blasted, and subsequently polished. I had forgotten to send them away for chemi cleaning on Wednesday. A typical mistake, too busy on the build to remember little things like that.

So now the earliest they will be back is Wednesday.

It serves me right for lying to you, these weren't made by me, but my dog Bandit, my new apprentice.

Just joking of course. This commission wasn't for a customer, but myself.
I had to keep it a bit of a secret because John S 1st comes surfing on the site.

At the show today I was going to present one to John S 1st, after 2 years as my internet apprentice, and my first time meeting him, I was going to show him a bit of recognition for how well he has progressed. A second one was going to be given to an engine collector I know, and is displaying at the show, he helps me out when he goes to the States every few months, getting me bits and bobs that I want, it was just to show my appreciation for what he does for me.

The third is still a secret.

So much for being well planned, fallen flat on my face with this one.

I do have a few pre assembly photos, but I am just too tired at the moment to make up a post. I will do it when they are all assembled with flywheels, before they are sent away.

Got to get some sleep now, early start in the morning to go to the show.

Rick,

Did a post late last year about blinging up an engine, I think it might be in the tips and tricks.
Can't remember what was in it, but if it doesn't explain it enough, just let me know and either I or someone else will give you the lowdown.

Ralph,

It is a bit late now for you to read this, but if you do, I will bring some bits to the show for you, for you to try the engine turning with.

John
 
Bogstandard said:
Got to get some sleep now, early start in the morning to go to the show.

It will all come good John, don't fret ;) ............. just enjoy the show ;)


and don't forget your camera ;D

Have a great day 8)

Dave
 
It wasn't until early this morning that the flywheels were picked up, so they will be a few days, but before that I had a re-look at the engine and decided that the conrod looked a bit too heavy still, so just to pass the time, I will show you a few ideas that I had, plus a tip if you want to build your own engine.

This first sketch shows a couple of ideas I had for the conrod, the first was quickly rejected because it was too futuristic to go with this engine, maybe sometime in the future this design will be used. The second one looked promising, so that was the one I went with.
The third bit of the sketch shows how to get the figures right if you want to design and build your own. The centre point of the crankshaft should be exactly the same height as the front pivot point of the conrod. The fingery doodah that you push up and down on can have its pivot point anywhere, just remember that if the finger pad is not on the centre line of the pivot point, you will get a strange 'feeling' as it is operated. The closer the pivot point is to the conrod pivot, the more up down movement will be given on the pad, the lower, the less movement will be required on the pad.
I found that 3" was OK for me between front and back standards centre points. 2.5" or even 6" would work just as well, just depends how long you want the engine to be. It makes no difference to the stroke lengths.
The bit of geometry is showing how to calculate the con rod centre length when using my settings. Just substitute your point centres and crank throw, and find the hypotenuse length of a right angle triangle. There are loads of little programs about that will do this for you, I posted a little one in the downloads section.
If you don't do this calculation, when the crank is vertical, up or down, your front doodah will not be vertical and so you will get wierd throws either way on the finger pad.

finger2sketch.jpg



This pic shows the finished standards. Bearings fitted, a dab of coloured paint to give a highlight and you will notice that I have modified the front of the base on the rear standard to make it 'flow' a bit better.

finger2bits23.jpg



I had already made and finished the conrods, but as I said, they still looked like they needed something else. So I carried on with the teardrop theme and shaved them down a bit. First I hacked a bit away on the miller, and then took to handwork again.

finger2bits24.jpg



A few months ago I couldn't have tackled handwork like this, but now with my new found mobility I can't get enough of it. The shaping again was all done by eye and feel, and takes about two hour for each rod, but to me it was worth it. It is very difficult to get shapes like this on a manual machine.

finger2bits25.jpg



A bit of a closer shot showing the hand profiling, just needs fine dressing and polishing. To me, a definite improvement from the original idea.

finger2bits26.jpg



A rear shot of a rough assembled engine.

finger2bits27.jpg



This is a side shot of the engine with a rough cut conrod awaiting profiling. It is now I really would have liked to have the crank webs shaped in the teardrop style, but it is a bit late in the game for that to happen.

finger2bits28.jpg


Once the flywheels are back and fitted, I can just knock up the correct spacers and retaining plugs for all the pivot points. The reason I won't do it before is that I will try to match them to the flywheel spinner.
BTW, the engines aren't in final shine yet, that only takes a couple of minutes.

John
 
Looking good John :) The recipients should be very, very happy :D

I wish I'd known those type of calc's when I started.... would have saved me hours of testing!
Still, I enjoyed myself doing that too :D



Ralph.





P.S. I got my polishing kit today ;D So tomorrow I see what I can do!!
Then engine turning! ;D
 
Ralph,

Remember, it is the soap that does the polishing, not the wheel. So in the beginning you might need to push a bit harder, so use a harder wheel, on final buff it is just a matter of holding it in the path of the soft flaps. Rather than up and down or side to side, try diagonal, it helps to alleviate the gouges on the not too smooth surfaces. On the last floppy mop, only ever use the chalk supplied.

For the engine turning, do your calculations first. If you need to know, just ask away.

Also, as I said about those bits I gave you, no abrasive needed and WD40 or a bit of paraffin if using them on ali, or WD40 on anything else. It is only there as a lubricant and to stop the end clogging up.

BTW Ralph, remember us talking at the show about a small lathe for small bits, and I told you it wasn't needed. Here is a part I turned up using my full sized four jaw. A big one will always do a little but not the other way around.

Crankshaft-1.jpg


The crankpin is 1mm diameter.

John
 
Thank you John. Duly noted and will concentrate!
That crank.... I'm going to have to practice before I can make one like that! I assume the engine it belongs to is not too big either?

I'm going out to my shop now to flat my baseplate ready for the polishing tomorrow, I'm quite excited about the whole deal! ;D

I'll post the results in 'work in progress ' When I have them to a satisfactory level :)


Ralph.
 
I've never built a finger engine. However, with my burgeoning supply of grandchildren (I'm due my third grandson come September), I suppose I'll have to do four (got a granddaughter too).

I think I'll try for something a bit different. Go up to Hollywood and get one of those realistic fake hands they use in the movies, cut off the forefinger and mount it on a small lever actuator powered by a proper steam engine. Somehow the idea of a steam driven "finger engine" appeals to me.
 
mklotz said:
I think I'll try for something a bit different. Go up to Hollywood and get one of those realistic fake hands they use in the movies, cut off the forefinger and mount it on a small lever actuator powered by a proper steam engine. Somehow the idea of a steam driven "finger engine" appeals to me.

How about a solenoid powered finger engine. That should be pretty easy to do.

Chuck
 
Come on Marv, play the game.

Are you trying to scare your grandkids to death?

John
 
John ,I reckon that Pat Jennings is your next door neighbor and that it's his hand in the photo, and the crankpin is really 5mm diameter!

Giles
 

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