Aren't you afraid that the cast flywheel will come apart when you rev them up?
Air compressor engine
- Thread starter stevehuckss396
- Start date
Help Support Home Model Engine Machinist Forum:
Aren't you afraid that the cast flywheel will come apart when you rev them up?
- Joined
- May 27, 2010
- Messages
- 2,999
- Reaction score
- 1,171
Hi Steve,
Would love to your engine started,running and roaring away.
Regards
Gus Teng.
waynesmotors
Member
- Joined
- Oct 24, 2012
- Messages
- 7
- Reaction score
- 0
Hi Steve
I havn't had any trouble with flywheel coming apart. I put gov. on my engine to keep them from running
to fast. But I have had gov. to stick on first time start up and the engine would run away. They will jump
kindy high if you don't bolt them down. I don't see how fast I can make a motor run I try to see how
slow I can make it run.
Wayne
I havn't had any trouble with flywheel coming apart. I put gov. on my engine to keep them from running
to fast. But I have had gov. to stick on first time start up and the engine would run away. They will jump
kindy high if you don't bolt them down. I don't see how fast I can make a motor run I try to see how
slow I can make it run.
Wayne
t.l.a.r. eng
Well-Known Member
- Joined
- Feb 9, 2009
- Messages
- 81
- Reaction score
- 14
Pressure cast flywheel that expired on a 3-1/2 horse Techumseh years ago when I was a kid.
Engine modified ;D
I can still hear how sudden it stopped! My finger was on the carb throttle until the expanded cooling shroud knocked my fingers away from the carb.
Learned a few things that day. A sand cast scares me even to this day.
Later in life started blowing up steel things drag racing.
Engine modified ;D
I can still hear how sudden it stopped! My finger was on the carb throttle until the expanded cooling shroud knocked my fingers away from the carb.
Learned a few things that day. A sand cast scares me even to this day.
Later in life started blowing up steel things drag racing.
Lakc
Well-Known Member
Pressure cast flywheel that expired on a 3-1/2 horse Techumseh years ago when I was a kid.
Engine modified ;D
I can still hear how sudden it stopped! My finger was on the carb throttle until the expanded cooling shroud knocked my fingers away from the carb.
Learned a few things that day. A sand cast scares me even to this day.
Later in life started blowing up steel things drag racing.
Sounds like a lesson well learned. However, as small as some of the cars are today, no reason you cant adapt a flywheel off something like a 3 cyl Chevy sprint or the like...
never thought of that. i'll look into it after the starter gets here.
johnny1320
Middle aged Member
- Joined
- May 15, 2013
- Messages
- 149
- Reaction score
- 16
Hi Steve how about a decompression valve like on the old Cummins engines the push tubes had a washer (flange) in the middle with a fork that would hold the intake valve open, crank her over and release the compression, larger singles have it built right into the cam and centrifugal force disables it. just an idea.
very cool modifications! i think you need to get rid of the ugly flywheel and machine and anodize a custom one! you could try using a model airplane 12v starter. all you need is a cone in the front of the engine in place of a prop spinner.
if you have not already sorted out your copper pipe oxidation, here is my experience with it. i have a little experience making jewelry out of brass, bronze, and copper. in order to join pieces, we used hard silver solder which melted at temperatures above 1000 degrees F, so the metal would get considerable oxidation on it, and the flux would crystalize all over it and it looked like crap. we then dropped it in a "pickle" solution which was basically acid. it would clean all the oxide and flux off in a few minutes and leave an etched appearance on the metal. i have experimented with using vinegar with good results. mix white vinegar with a little bit of salt and some H2O2(hydrogen peroxide). if you leave it in too long(several hours) it will start to dissolve the copper! leave it in for a minute or two and rinse it. if there is more black oxide on the copper leave it in a little longer. then sand the extra solder off and polish it up!
if you have not already sorted out your copper pipe oxidation, here is my experience with it. i have a little experience making jewelry out of brass, bronze, and copper. in order to join pieces, we used hard silver solder which melted at temperatures above 1000 degrees F, so the metal would get considerable oxidation on it, and the flux would crystalize all over it and it looked like crap. we then dropped it in a "pickle" solution which was basically acid. it would clean all the oxide and flux off in a few minutes and leave an etched appearance on the metal. i have experimented with using vinegar with good results. mix white vinegar with a little bit of salt and some H2O2(hydrogen peroxide). if you leave it in too long(several hours) it will start to dissolve the copper! leave it in for a minute or two and rinse it. if there is more black oxide on the copper leave it in a little longer. then sand the extra solder off and polish it up!
I have a starter and it wouldn't turn it over. ry drill and that wouldn't do it. Then I did the electric drill and it ripped the chuck right off the drill. I bought a starter for a 20 HP briggs stratton but it spins the wrong way. I am going to make a flywheel and then an idler gear between the flywheel and starter to reverse it. Shes a mean one.
I think it has more to do with where you are applying the starting torque. When you pull the rip cord on a briggs your not pulling right at the center of rotation like a RC starter does. If I get a couple gears on there the starting torque will be a few inches off center line of rotation and crank a lot easier.
She's 8.5:1
johnny1320
Middle aged Member
- Joined
- May 15, 2013
- Messages
- 149
- Reaction score
- 16
Most small single cylinder engines have decompression lobes on the camshaft it opens the exhaust valve just slightly just before tdc and when it starts it is disabled by centrifugal force. As I said before in case you missed my post Steve. Should be easy for a man of your talent
Most small single cylinder engines have decompression lobes on the camshaft it opens the exhaust valve just slightly just before tdc and when it starts it is disabled by centrifugal force. As I said before in case you missed my post Steve. Should be easy for a man of your talent
I doubt I need it. Just need the right starter
Well i read through all this and you sir are a legend! I want to see and hear this thing run, so heres a bit of a tip that i hope helps you out: You can pull the starter you bought apart and make it run backwards, basically set the body of it 180 degrees out should do the trick. We get a few home repairs we have to un-do like that at work (motorbike mechanic by trade) they usually have locating lugs on them to make sure you put them together right, you can just grind them off or do what my customers do and force it on regardless... :/
Anyway, give it a shot, depends on the starter but if its the usual permanent magnet type, 180 degrees out should reverse the rotation. If its the other type a little rewiring will reverse the direction.
Anyway, give it a shot, depends on the starter but if its the usual permanent magnet type, 180 degrees out should reverse the rotation. If its the other type a little rewiring will reverse the direction.
The motor rotation is not the problem. When the motor spins it throws out the starter gear. It has to spin in that direction to toss out the gear. Thats just the way it's built. It's no big deal I just need to redesign. I think what i'm going to do is make a flywheel with the correct teeth, mount the starter to work, and make a camshaft to reverse the direction of the engine. I have another project that has been moved to a higher priority until I find a chunk of steel large enough to make a flywheel.
Dang thought they might have a sprag/one way bearing setup, sounds like they are a small car setup. ah well signed up here now will patiently await seeing this thing live, always looked at air compressors and wondered, can't wait to see you finish it
Oh also if you run into needing valve seat cutters again, mikesxs.net sells a set for motorbikes, $130 ish for the kit, should do the trick for what you've done here, too late now you made some if your own, even better!
thought they might have a sprag/one way bearing setup, sounds like they are a small car setup. ah well signed up here now will patiently await seeing this thing live, always looked at air compressors and wondered, can't wait to see you finish it Oh also if you run into needing valve seat cutters again, mikesxs.net sells a set for motorbikes, $130 ish for the kit, should do the trick for what you've done here, too late now you made some if your own, even better!
Last series of postings were 2 months ago. I hope there's more to this compressor-to-engine conversion.
I got into this forum after the conversion was started, and I have many questions regarding the thoughts behind many of your construction and machining methods. I have learned by looking at the pictures and reading through all the postings, explanations, etc. Most of my questions will now be out-of-context. Sorry.
For example: Back towards the beginning of the conversion, you needed to machine intake and exhaust valves, and you made them by silver-soldering the stem and head together, then machining them to dimension. I also watched through the attached a video showing the construction of the valves. You used "soft" solder, which has a lower melting point than "hard" solder. When the engine is running, wouldn't the exhaust gas passing by the soldered joint on the exhaust valve, melt the solder, and cause a disaster if the valve pieces became separated? I'll ask more questions later.
Can't wait for the the final chapter.
Good luck with the rest of the conversion.
Frank
EDIT: Totally got my question wrong regarding solder type. I should have asked why the higher melting point alloy of silver solder wasn't used. The reference to "soft solder" is a total mistake.
Steve was kind enough to clear up this question in a later post.
I got into this forum after the conversion was started, and I have many questions regarding the thoughts behind many of your construction and machining methods. I have learned by looking at the pictures and reading through all the postings, explanations, etc. Most of my questions will now be out-of-context. Sorry.
For example: Back towards the beginning of the conversion, you needed to machine intake and exhaust valves, and you made them by silver-soldering the stem and head together, then machining them to dimension. I also watched through the attached a video showing the construction of the valves. You used "soft" solder, which has a lower melting point than "hard" solder. When the engine is running, wouldn't the exhaust gas passing by the soldered joint on the exhaust valve, melt the solder, and cause a disaster if the valve pieces became separated? I'll ask more questions later.
Can't wait for the the final chapter.
Good luck with the rest of the conversion.
Frank
EDIT: Totally got my question wrong regarding solder type. I should have asked why the higher melting point alloy of silver solder wasn't used. The reference to "soft solder" is a total mistake.
Steve was kind enough to clear up this question in a later post.
I will ask this question to the forum members again. I originally asked a similar question back in March 2013 but didn't get any answers.
The set-up:
I have read about many of these compressor-to-engine conversions. Most of these become Hit-and-Miss type-engines, and most become demonstration engines at shows, like Cabin Fever Expo. So, you convert the compressor and make a running engine.
The questions:
Can these compressor conversions do real work? The above conversion outlined by Steve, certainly looks like it has the cajones to do something useful besides just burning gas. Many conversions come close to having the bore and stroke of some of the antiques, so these conversions must be at least as powerful as some of the old engines. Are these original compressors-now-engines built strong enough to do consistent work? Will the bearings last, will the con-rods hold up under loads, etc.
Generally, are air-compressors designed to be stronger than the equivalent-sized, bore and stroke, gas engine?
Just wondering....
Frank
The set-up:
I have read about many of these compressor-to-engine conversions. Most of these become Hit-and-Miss type-engines, and most become demonstration engines at shows, like Cabin Fever Expo. So, you convert the compressor and make a running engine.
The questions:
Can these compressor conversions do real work? The above conversion outlined by Steve, certainly looks like it has the cajones to do something useful besides just burning gas. Many conversions come close to having the bore and stroke of some of the antiques, so these conversions must be at least as powerful as some of the old engines. Are these original compressors-now-engines built strong enough to do consistent work? Will the bearings last, will the con-rods hold up under loads, etc.
Generally, are air-compressors designed to be stronger than the equivalent-sized, bore and stroke, gas engine?
Just wondering....
Frank
Hello Frank!
That was not soft solder, that was sil-flo Silver solder. It's melting point is just south of 1000 degrees F
