ESE's works engine tuner

**OopsClunkThud** · 12th December 2016, 05:49

You can also cut a hemisphere on a knee mill with the head set at an angle. The combination of the angle and cutter determine the radius of the hemisphere. The diameter of the cutter equals the chord length.

**jasonu** · 12th December 2016, 06:38

Originally Posted by G Jones

I may have posted this before - can't remember - whether it's necessary to follow piston radius or not for squish - it's what I wanted to do with our TZ350 - don't have easy access to cnc - so found a way to get it done with what i did have available...

I like that method. Very 'bucket racing'.
To do mine I hand ground a piece of my (at the time) employers carbide (or was it tool steel I don't remember) into the shape of the dome that I thought was correct and used it to cut the shape. I then used carborundum paper to sand it smooth then brasso to do the final polish. Right or wrong it seamed to work OK.

**G Jones** · 12th December 2016, 08:17

Originally Posted by jasonu

I like that method. Very 'bucket racing'.
To do mine I hand ground a piece of my (at the time) employers carbide (or was it tool steel I don't remember) into the shape of the dome that I thought was correct and used it to cut the shape. I then used carborundum paper to sand it smooth then brasso to do the final polish. Right or wrong it seamed to work OK.

Always more than one way to "skin a cat"

I looked at and thought about this for quite a time - then realized I'd got the ideal radius cutting tool in the rotary table - looks a bit cack but does the job very well - more important to get it repeatable with the twin engine - you want both to be identical... - you wouldn't want to see the tooling I made to put circlip grooves in RD250 cases to use for TZ350...

**adegnes** · 12th December 2016, 11:39

The forming tool way is nice, cause then your not restricted to a hemisphere shape!

If anyone's curious to know what's going on with the Spx, I've ordered some urethane resin and will be making new engine mounts with cast in bushings. Crossing fingers for that to soak up enough vibration to keep my carb happy. Video coming.

**adegnes** · 12th December 2016, 22:35

More from your favorite entertainer!

did you cheak the otherside of the crank as it looked like it was going up and down in video , hard to see

**wobbly** · 13th December 2016, 06:40

Only one small step from famous to legendary Frits.

**adegnes** · 13th December 2016, 06:49

Originally Posted by Frits Overmars

Thanks for the credits Alex. You'll make us famous yet

.

:

Originally Posted by mr bucketracer

did you cheak the otherside of the crank as it looked like it was going up and down in video , hard to see

I'll have to recheck it. Thought that if one side is running true - both sides are good. If the shafts aren't bent(could be the case here).

**wobbly** · 13th December 2016, 07:43

Never assume - its just an error just waiting to be revealed.
The pin can be " cocked " in a web hole, or both ,especially with a crank that moves as easily as that one does.
If it moves like that when applying hardly any force, imagine whats going to happen at 14,000 rpm.
Only fix for a shitter like that is to Tig the pins after truing,special stepped pins, or bin it.
The only way to ensure pins, or webs arent " cocked " when pressed together, is to use a die set that keeps all the faces parallel.

**adegnes** · 13th December 2016, 07:55

Originally Posted by wobbly

Never assume - its just an error just waiting to be revealed.
The pin can be " cocked " in a web hole, or both ,especially with a crank that moves as easily as that one does.
If it moves like that when applying hardly any force, imagine whats going to happen at 14,000 rpm.
Only fix for a shitter like that is to Tig the pins after truing,special stepped pins, or bin it.
The only way to ensure pins, or webs arent " cocked " when pressed together, is to use a die set that keeps all the faces parallel.

True true.
I've told the owner of the crank that I highly recommend he get a new one. I mean I could probably bend it out of true with just my hands.

**F5 Dave** · 13th December 2016, 12:14

Working on the principle of the stopped clock that's dead accurate twice a day: the bendy crank is probably true , we'll, sometimes. . . Is 'often' acceptable?

**jonny quest** · 14th December 2016, 01:31

That could be your vibration problems. Crank isn't true

**adegnes** · 14th December 2016, 02:34

Originally Posted by jonny quest

That could be your vibration problems. Crank isn't true

Hmm... Could be. I've indicated both sides of the Spx crank though, within 0.01mm

But just to get this straight

, if I measure no runout on one side, and the shafts are not bent, is it possible for the other side to be out of true? It's relative and all that.
When I'm indicating one side and I can't get it true I assume that it's cocked on the pin, hit one side to see if it gets better/worse and work from there. Usually does the trick.

**wobbly** · 14th December 2016, 08:06

Yes it easily possible to have one side read zero, and the other wave about at 0.03 - as you say if the pin isnt true
in the crank wheel bore - I see this all the time.
Have you checked the crank, now its been installed and run.
Could be miles out if the press fit isnt sufficient.

Thread: ESE's works engine tuner

Thread Tools

Thread Information

Users Browsing this Thread

Bookmarks

Bookmarks

Posting Permissions