My very first Webster Petrol IC Engine

[vcutajar]

Good progress Gus. Moving along at a steady rate. Keep it up.

Vince

 

[AussieJimG]

That's coming along just fine.

 

[gus]

Been an easy/relaxing morning,fitting in the gudgeon pin made from Nachi Drill Stem, piston mini oil tube,drilling the con-rod small end oil hole and turning the the Cylinder Oil.
Cylinder Oiler done and installed with needle valve. Used aluminium from scrap bin.
Oil drops appeared to be well controlled.Been a good day with no rejects/scrapping.

Will move on to make Intake/Exhaust/Carb Manifold next week. Never done one before and definitely not this miniature. The mini tappet valves worry me.
Will take sweet time to make manifold.

After this will make fixtures and dividing head and mandrel to cut the 25T pinion gear for the timing gear train.Again another worrying job.OK Gurus.Your expert advice requested.
For this very first job may go brass or aluminium.

 

[AussieJimG]

That cylinder oiler looks good

Jim

 

[errolf2]

I have used these hone they give a brilliant finish
http://www.brushresearch.com/product-line.php?line=1
Good Luck
Errol

 

[Brian Rupnow]

Gus---There is a trick you should be aware of when you go to machine the valves. I have posted about this before, but I can't remember where now. If you try and turn down the full length of valve in successive passes, once the diameter is reduced close to where you want it, the material will start to deflect away from the cutter, causing major headaches----This is assuming you are holding the work in a 3 jaw chuck without a tailstock center. The trick is to turn only about 1/4" of length down close to the desired diameter, maybe .001 to .002 larger than finished diameter. Take note of the numbers on your crossfeed dial, then back out and turn the next 1/4" of material down. Keep doing this until you have the valve stem to the correct length, then polish to size with fine emery paper. By doing it this way, you can avoid the deflection which is sure to happen otherwise and cause you grief. I think it was George Britnell who gave me this advise when I built my first i.c. engine. Make sure that you have the part that the valve stem fits into machined and finish reamed to size before you make the valves--That way you can keep trying for fit without "unchucking" your valve and lose concentricity with your chuck.----Brian.

 

[AussieJimG]

And further advice I got from George Britnell is that it is only the part of the valve stem that slides in the guide that needs to be spot on for size.

Jim

 

[gus]

Gus---There is a trick you should be aware of when you go to machine the valves. I have posted about this before, but I can't remember where now. If you try and turn down the full length of valve in successive passes, once the diameter is reduced close to where you want it, the material will start to deflect away from the cutter, causing major headaches----This is assuming you are holding the work in a 3 jaw chuck without a tailstock center. The trick is to turn only about 1/4" of length down close to the desired diameter, maybe .001 to .002 larger than finished diameter. Take note of the numbers on your crossfeed dial, then back out and turn the next 1/4" of material down. Keep doing this until you have the valve stem to the correct length, then polish to size with fine emery paper. By doing it this way, you can avoid the deflection which is sure to happen otherwise and cause you grief. I think it was George Britnell who gave me this advise when I built my first i.c. engine. Make sure that you have the part that the valve stem fits into machined and finish reamed to size before you make the valves--That way you can keep trying for fit without "unchucking" your valve and lose concentricity with your chuck.----Brian.

Hi Brian,

Thanks for the tip. Am about to machine the tappet valve today or tomorrow.
Valve blocks marked out and will be done today. 8:15am Monday 17 now.
Taking my sweet time to do a good job. Will post.

Been wondering how to machine the tappets since day 1 .

Thank You again. Brian is like my Guardian Angel watching my every step.
You may not believe it. 1960 Flew off my first 50cc Yamaha Motorbike while stamping on brakes to avoid hitting a cyclist who suddenly crossed my path from a side lane w/o warning.:wall::wall::wall: Gus flew into the air did a somersault and landed firmly on his feet.Gus was not a gymnast!!!. Could have died or badly crippled. Two middle age bystander came out and ask Gus where I learnt this Chinese Martial Art. ha Ha Ha.

 

[gus]

I have used these hone they give a brilliant finish
http://www.brushresearch.com/product-line.php?line=1
Good Luck
Errol

Hi Errol,

Thanks.

 

[Art K]

Gus,
I have to admit to not using the George Britnell method of turning a valve, or even knowing that method even existed at the time. I was building my version of the Upshur vertical single. I turned the valves in the 3 jaw between centers sanded the high spots with a 6 inch scale behind it and when I got close used a fine stone and with a micrometer to check the finished the size, then turned the end off to length. lots of starting and stopping the lathe.
Art

 

[Swifty]

Following along Gus, progress so far looks great. Don't let cutting the gear worry you, approach it with a positive attitude and you will have no trouble.

Paul.

 

[gus]

Following along Gus, progress so far looks great. Don't let cutting the gear worry you, approach it with a positive attitude and you will have no trouble.

Paul.

Hi Paul,

Thanks for the support.

Just cannot imagine gear cutting would come back staring at me after 52 years.Timw flies and Gus is now 70 and very healthy.
Was taught gear cutting in one simple lesson and went on to cutting gear blank and mount on mandrel and mill tooth by tooth. Glad to say Gus finished cutting a gear with all 32 teeth.
Some of trade school class mates had 31 1/2
or 32 1/2 teeth.:wall::wall::wall:

 

[gus]

The intake/exhaust valve manifold to 10 hours to saw,mill,drill,ream and skim.
Foto shows the 1" x 1" x 3/4" little monster.
Will take a break away from "Webster" to thread 200 pcs of studs for the "Nuts & Bolts" Supplier
at S$2 per pce. Some production plans and Work Instructions required to make these parts good looking fast and labour saving. Have to work smart.

S$400 good money to buy some tools.

 

[Brian Rupnow]

Looking good Gus. Damn, that's a big sparkplug you've got in that thing.-Is it out of a car?

 

[gus]

Looking good Gus. Damn, that's a big sparkplug you've got in that thing.-Is it out of a car?

Hi Brian,

Hard to buy small spark plugs in Singapore.Still trying. There is one outlet in the net but he does ship to Singapore. Will try out the PortaPack Grass Cutter
Stockist.Believe they have small plugs. Or try out the aeromodel engine stockist.
Meanwhile make do with the monster plug.:wall::wall::hDe::hDe:

Will be moving on to cutting the tappet valves. How I go about lappping to seat with valve guide?
Drilling the 0.040 hole on valve stem looks formidable.Plan to jig drill.

Please advise on both.

I have Webster sitting on my Canon printer.
Looks more like a beloved pet.

 

[Brian Rupnow]

Best way I have found to get a good valve seal is---Cut a VERY small seat area ---not larger than .010 to .015". Cut the seat at 90 degrees included angle and cut the valve face at 92 degrees included angle. This will essentially give you a "line contact" between the valve face and the top of the seat (farthest away from the combustion chamber.) Use a 600 grit lapping paste, and be VERY careful that its only on the face of the valve and the seat. You DO NOT want to lap the stem into the guide. Shove the valve through the valve cage and grip the end of the stem with a pin vice. Hold a slight pressure between the valve and the valve cage and roll the pin vice back and forth between your thumb and finger, lifting the valve off the seat and back down again every 4 or 7 semi-rotations to pull fresh lapping compound into place. How long do you do this?--If you have lead a good clean life, then 15 to 20 semi rotations may do it. If, on the other hand you have lead a wicked sinfull life like myself, you may have to do it until your thumb and finger get numb.--And then do it a bunch more times!! I find getting valves to seal properly to be the hardest part of building an i.c. engine. Others have no problem.---And the worst part is, you won't know whether or not you have a good seal until you get the whole damned engine assembled and see if it has compression or not. As far as drilling a hole for the keeper---Man up, Gus!!! That's easy---In fact I find it a heck of a lot easier than trying to machine a microscopic groove for an e-clip. Do use a very small center drill to start the hole, and do keep the RPM really "up there" with lots of lubrication.---Brian

 

[gus]

And further advice I got from George Britnell is that it is only the part of the valve stem that slides in the guide that needs to be spot on for size.

Jim

Hi Jim,

Thanks for the expert advise. With this rrquirement met,I guess the engine will run much quieter.

Need your expert advise. How do I upload on YouTube? This is to facilitate
uploading movie shots of "Webster" when it gets started and running.Will be months away.

Right now machining the valve guides.Your advice was J.I.T.(just in time).
The Webster has taken me into untried territories. Never done any parts so miniature and yet precise.


Regards,

Gus.

 

[Brian Rupnow]

If you find out how to upload to youtube, let me know. Sometimes I can, most times I can't.

 

[gus]

Valve guides done and installed. The intake/exhaust valve manifold now looks authentic with valve guides intalled.
Did reaming to accept tappet valve stem.
Next will be the miniature tappet valves. Going in with fingers cross.Am prepared mentally to have some contributions to the scrap bin.

 

[gus]

With all the expert advice given and taken.First Tappet valve was finished and thought machining same was nail biting. Same took an hour to turn.Manifold assembled with inlet valve.

OK gurus. How to drill the teeny weeny hole for cotter pin.