Going to start this section for some info of RD machine work and things I had to self teach me...Now I'm older I want to share this 2stroke branded mind of mine to share as much of it as I can for others to learn and carry the torch as I would say...
When I lost my dad 10 years ago, I realized I could have learned more from him and made me mad at myself for not asking him.
This is my way of honoring him through the rest of my life! :patriot:
Chuck
Team Scream Racing LLC
Joshua brought me his Daytona engine to start going through a performance rebuild/build for a RD hotrod saturday night rides.
He did a teardown of the engine and he bought a Vapor Honing blast machine this year and has Vapor blasted everything clean, very pretty and ready for machine work.
He can post here if he wants business for us RD builders.
(https://photos.imageevent.com/supertune/joshuard400/large/IMG_1725_1_.jpg)
I'll cover more about boring cylinders later. I'll put up a little here on his 2V0 Daytona cylinders.
One of the first things we saw was cylinders were 2 different bore sizes, the left was .0055 loose clearance standard 64.00mm bore and the right a loose .007 clearance @64.50mm bore. :eek: :umm:
The 64.50 was worn so bad from running .007 piston clearance it wouldn't clean up at 64.75mm so they both got bored to 65mm in my Rottler boring machine.
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_165724.jpg)
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_165717.jpg)
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_180843.jpg)
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_180824.jpg)
Rottler boring machine video.
Sorry for the sound noise, been really hot in Florida, *95 +, and I had the big wall fan on....(will turn it off next time)
https://photos.imageevent.com/supertune/joshuard400/20190824_165638.mp4 (https://photos.imageevent.com/supertune/joshuard400/20190824_165638.mp4)
The next thing I was concerned about was the condition of the decks of the top of cylinders, looked pretty beat up over the years.
Did a quick measurement of the deck heights and seen they were not the same, so we're thinking they could be a mis-matched set?
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_181007.jpg)
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_180945.jpg)
Time to set them up in the mill for some machining of the decks.
I have a CNC made fixture I mount on the mill table that holds both cylinders at once and square to the base gasket.
Next I use a quill dial indicator and get fixture straight and have some long 8mm allan bolts to tie cylinders down to fixture.
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_184636_001.jpg)
Video
https://photos.imageevent.com/supertune/joshuard400/20190824_184642.mp4 (https://photos.imageevent.com/supertune/joshuard400/20190824_184642.mp4)
Mounting bolts to the fixture.
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_185116.jpg)
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_190703_1.jpg)
Took the first cut of .003 in, didn't even touch the shorter cylinder...
https://photos.imageevent.com/supertune/joshuard400/20190824_191230.mp4 (https://photos.imageevent.com/supertune/joshuard400/20190824_191230.mp4)
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_191320.jpg)
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_192242.jpg)
Cut another .003 thousandths...
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_193018.jpg)
Almost there! .002 more.
(https://photos.imageevent.com/supertune/joshuard400/large/20190824_194116.jpg)
Finally got it good enough not to be an issue. ;D
https://photos.imageevent.com/supertune/joshuard400/20190824_194009.mp4 (https://photos.imageevent.com/supertune/joshuard400/20190824_194009.mp4)
I'll post some more on some other stuff soon!
Chuck
Marvelous work!
Thanks Chuck, this is going to be a great thread!
:notworthy:
I did a pair of RZ heads and this is some of the things it takes to do this kind of work...
Like a Daytona 2V0/3J7air cooled one piece are harder to machine.
With these air cooled heads, I machine them in half and cut like a single normal RD head or any head that uses a center sparkplug in the head.
I start by cleaning the headgasket surface and lap the head with some 220-320g wet N dry with some mineral spirits on my granite plate.
Next I will measure the sparkplug seat and write down the number on the head, measure both and then ready to head to the mill and spot face the sparkplug seats to set height and square to the headgasket surface.
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190820_171722.jpg)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190820_171453.jpg)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190820_171457.jpg)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190820_171505.jpg)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190820_171509.jpg)
I now mount the head in the mill to spot face the sparkplug seats. This will give me a '0' register height once mounted on the lathe spindle when time to machine head, squish and chambers.
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190816_163211.jpg)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190816_164031.jpg)
I mill the shortest number first, once it spotfaces clean, I '0' out the digital height readout.
Now move to the taller height and mill it to the '0' height. now both are exactly the same '0' height.
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190816_164104.jpg)
Lookin good Chuck!
Would love to see some pics of my topend on here :whistle:
Quote from: pdxjim on August 25, 2019, 08:18:27 PM
Lookin good Chuck!
Would love to see some pics of my topend on here :whistle:
Yours will come up too!
Video of the mill running to do the spotfacing, this is the other RZ old race head I did for another job about the same time.
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190819_105935.jpg)
https://photos.imageevent.com/supertune/rdheadmachining/20190819_105945_1.mp4 (https://photos.imageevent.com/supertune/rdheadmachining/20190819_105945_1.mp4)
Time to start milling the deck surface.
Here's your shot Jim...Your LC in the mill! :eek:
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190706_122700.jpg)
Back to the RZ heads...
Somehow the sound is lost in uploading to my hosting site? Stupid computers... :umm:
https://photos.imageevent.com/supertune/rdheadmachining/20190816_185920.mp4 (https://photos.imageevent.com/supertune/rdheadmachining/20190816_185920.mp4)
Sound is back on this next video!
https://photos.imageevent.com/supertune/rdheadmachining/20190816_184709_1.mp4 (https://photos.imageevent.com/supertune/rdheadmachining/20190816_184709_1.mp4)
Then I'll use the single cutter for the .005 final pass after doing the rough milling with a smaller flycutter to take .020 a pass as it usally takes about .045 to .050 to get them down to be able to work with the squish band cutting as they are cast into the head and are all over the place with runout.
https://photos.imageevent.com/supertune/rdheadmachining/20190819_114408.mp4 (https://photos.imageevent.com/supertune/rdheadmachining/20190819_114408.mp4)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190819_114345_026.jpg)
Here we go for the next setup...The lathe work!
Mount and true in my sparkplug spindle I made in a collet 5C chuck.
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190706_122638.jpg)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190706_122650.jpg)
I'll go and check/measure my piston size that I'm going to use for the build the head is going on and go .030 more to use for the O.D. of my outer
bore of the squish cut. This gives me room to overbore the cylinders another 2 overbores at .25mm overbores. (.010 each)
I'll also check and set the lathe quill angle to + 1* degree over the piston and almost 2 degrees on a cylinder head that is going to be or use a O-ring seal rather than a headgasket. O-rings are real sensitive to not enough angle to keep the hot compression gases away from the o-ring
SET SPEED of the spindle NOW! VERY IMPORTANT!!! if you turn it on with a high speed setting...you can get hurt and or destroy a customers head or both!! :bang:
I can run it about 95-110 rpms in my lathe. 8)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190817_164122.jpg)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190819_100003.jpg)
Watch out for that head swinging!! :eek:
https://photos.imageevent.com/supertune/rdheadmachining/20190817_163526.mp4 (https://photos.imageevent.com/supertune/rdheadmachining/20190817_163526.mp4)
Now is the time you have to set the O.D. and the step in the head you will have to check with a mockup on engine and solder check to determine how deep the squish step needs to be, like when I go and do Joshua's head with a short deck height, his will be a little deeper as will a o-ringed setup when you lose a thick headgasket!
Jim, Another glory shot of your LC head!
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190706_105908.jpg)
Once the squish bands are cut to spec's... now have to machine the bowl out to set the squish ratio and the final compression ratio which is determined by the outer bowl diameter (determines how wide the squish band is) and head final CC volume.
Time for the next step...
Going to show you something that is a really cool tool I made.... :righteous: as no one ever showed me when I was learning.
Here's goes, I'm showing my secrets to all of you that are into this art of 2stroke workings.
(https://photos.imageevent.com/supertune/rdheadmachining/large/20170512_140706.jpg)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20170512_140714.jpg)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20180523_200838.jpg)
Another few shots for almost famous PDXJim and his LC!
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190707_180632.jpg)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190707_180650.jpg)
(https://photos.imageevent.com/supertune/rdheadmachining/large/20190707_180701.jpg)
Ok, getting late now you got to see a really cool tool!!
I made it with many holes to move in and out to control the bowl radius and works on all sizes of chambers, used this tool making custom domes for my monster twin cylinder 1200cc and 1400cc jetski engines at 95mm and 100mm bores!
Last Video for the night...
https://photos.imageevent.com/supertune/rdheadmachining/20190820_152228.mp4 (https://photos.imageevent.com/supertune/rdheadmachining/20190820_152228.mp4)
wow Chuck, I see why you cut the Daytona heads in half now.
:clap:
:metal:
So let's take this a bit further in theory...
Once you get the head cut, you then have to CC the head volume to get the compression ratio in your target range if running on pump gas or race gas...
You will always have to figure in how big the bore is as that can make a big difference in the final compression ratio
Here is the formula to reach this factor...we need to know how big the engine displacement is.
We have to know what the displacement of the engine is, specifically 1 cylinder.
Take the bore size and multiply by itself.
Example a RD350 at 65.00mm of bore and a stock stroke of 54mm.
Bore squared is: bore x bore.
So, bore x bore x stroke x .7854 divided by 1000 will equal the cc's for one cylinder, then x 2 will give total displacement of the engine.
65mm x 65mm x 54mm x .7854 divided by 1000 = 179.19 cc per cylinder.
Now 179.19 x 2 cylinders we get 358.4 CC's of engine total displacement.
Now that we know the displacement is 179.19 CC'c per cylinder we are now ready to mock up the engine and do a CC fill volume of the combustion volume with the engine together to get what we call Fill Volume (F.V.)
Mock the engine together, using some grease to seal the piston at TDC. (top dead center) grease with light coat on the headgasket and then put on the head and hand tighten the head bolts, not critical as we are not checking for squish clearances which do require a torque value .
to be continued...time for bed! Sorry I'm beat from the FL. summer heat! :thumbs:
Chuck
Do you recommend every time a cylinder is bored that the CC should get profiled?
No, I try to set the up for 2-3 more bores.
Yes, if going over 1mm from when there done the first time.
Bigger bores up the cylinder volume, so the compression ratio goes up.
Chuck
TBC? The suspense is killing me! :cheerleader:
OK.
The racing season just got done at Barber Vintage Festival...was really busy with racebikes and now the backlash of work missed while gone for a week.
C
When you have a moment, any chance of the next chapter?
Hardy,
I'm sorry...been everything I can do to keep up lately due to my Ford F-150 deciding to break the transmission for no reason...turns out to be a Ford manufacturing issue with a bad forward clutch drum breaking in thousands of F-150's!
Their goes $1900 out the window for no reason other I bought a Ford instead of a Chevy! :umm: :bang: :help:
Wish I would have known before buying a Ford.
Motor runs great, gets good fuel mileage and doesn't use a tic of oil...
Front brake pads will out last front rotor permanent sealed wheel bearings too! Found that out in December! :eek:
Oh crap...time to go home from shop it's 11:15....