32x40 H Gas engine

[Brian40]

Thanks for the O ring info I had made a note of that from reading your other builds.
so its the cam!!! the blank was turned between centres so I can return later to form the bearings etc but for the moment it was left at base circle diameter for max strength.
After forming the blank, it was on to the mill to cut away the base circle to produce the cam. that put the pucker factor up a bit I can tell you.


Brian.

 

[Brian Rupnow]

I have found that when cutting cams I can hold my breath seven or eight minutes at a time, just like those pearl diver guys in the south Pacific!!

 

[gus]

I have found that when cutting cams I can hold my breath seven or eight minutes at a time, just like those pearl diver guys in the south Pacific!!

Hi Brian,

Thats true. Thought I would die with cam cutting after losing 6 cams. Must be the breath holding that cut oxygen to my brains.:rant:

End of the story.Gus became ''cam smart''. The endmills must be very sharp and the brains even sharper.

Weather turning warmer there.

 

[Brian40]

I think the worst part is that I now have to wait until the engine is finished to se if it's all ok I will have nibbled my fingernails down to the elbows by then.
Now on to the sub assembly that carries the cam bearings --the oil pad for the cams-- and the drip feed oilers.
Never a dull moment 30 odd drawings done and a lot still to do. let alone the parts.
Thanks for the support. Brian.

 

[Brian Rupnow]

You will find, (or may know already) that unless you are aiming for extreme high performance, cams on four cycle engines are very forgiving.----and that's a good thing!!!---Brian

 

[Brian40]

Just a few more photo's showing the cam sub assy in the rough. the flat plate between the camshaft supports will be the mounting for the two drip oilers, one for the cylinder an the other for the big end.

Brian

 

[Brian40]

Not a lot today just milled out the shaft clearance and the pits for the cam lube felts Just to cold in the shop.

Brian.

 

[Brian40]

Next job on the list was to mount the cam sub assy and fit the oilers. the pipe work will come later
I also have made a start on the carb. and have ordered parts to make the on demand gas valve so things are really starting to move.

Brian.

 

[Brian40]

Yesterday was a big day ,the valves where put in and the rockers made.
At last it starts to look like a engine. the spark plug is ordered and the gasket material for the head so it wont be long before I can try the compression, carburettor is under way and the diaphragm for the on demand gas regulator has been ordered. It's all go in the shop at the moment.

Brian.

 

[gus]

Hi Brian.

Propane is a cleaner fuel for our DIY Engines. Please advise source of gas demand valve drawing.
Gus planning build a small 4 stroke engine using propane gas after Howell V-2.

 

[Brian40]

Hi Gus
This is the company that I am getting my plans and parts from
http://www.model-engine-plans.com/engineplans/bookshelf/demandvalve.htm

I do not know what the max size of engine this valve will cope with but I am going to give it a try
my engine is 32 cc .

Brian.

 

[RonGinger]

That setup using the 1-2-3 blocks as a clamp is a great idea, I will remember that one, thanks,

 

[Brian40]

Hi Ron
I use this set up all the time it's accurate and gets the head nearer the table so there is less flex in the column.
If you look at the early posts in this thread you will see lots of examples of it.

Glad you like it Brian.

 

[Brian40]

Limited shop time today it's just to cold but made some progress on the carb.

Brian.

 

[gus]

Hi Gus
This is the company that I am getting my plans and parts from
http://www.model-engine-plans.com/engineplans/bookshelf/demandvalve.htm

I do not know what the max size of engine this valve will cope with but I am going to give it a try
my engine is 32 cc .

Brian.

Hi Brian,
Thanks for vendor info. Best to buy this vendor, plan and diaphragm. Bought V-2 engine plans came from same.

 

[Brian40]

Not a lot done today to cold again, Coming up to 75 years old and feeling it, drilled the idle mixture holes and made the main ventury ? had to make the tool to cut the internal curve. Perhaps tomorrow I will make the mixture adjustment components ,!!

 

[Brian Rupnow]

Brian--That engine is turning out to be a real beauty!! What material did you cut your gears from? It looks like aluminum. I am surprised at your age. For some reason I thought you were much younger, probably in your middle fifties.--Not sure why. I tend to form impressions by people from their posts, and I am often surprised.

 

[Brian40]

The gears are 5083 alloy same as the crankcase etc, carb body is 6082.
I also am happy with the appearance of the engine it's nice to build something different from the run of the mill motors . at least any problems are all of my own making.
Time creeps up on all of us, I keep fairly active and sail most of the summer, but long stints ( over 12 hrs ) tend to make me tired so I leave the wife in charge and have a nap. after all she is only 72.

Regards Brian

 

[Brian40]

Made the mixture controls today and started on the outer end plate

slowly-- slowly. Brian.

 

[Brian40]

Not a lot of shop time today, but got the front plate done with the idle screw. and an air filter to stop Elephants falling into the engine !!!
Hopefully one more day will see it done, all we have to do then is wait to see if it works gas carb jets are massive compared. with those for liquid fuel so we will only know when the engine it test run what is going to work.

Brian,