Balance shaft? Will they take a CR250 gearbox as you can get 6sp boxes for CR's now. Looks good Neil, got my emails back to now.Originally Posted by Flettner
Hardcore Biker
Balance shaft? Will they take a CR250 gearbox as you can get 6sp boxes for CR's now. Looks good Neil, got my emails back to now.
Why Not???: MNZ975.
Great work. This is very interesting.
Neil, would it be possible to show a couple more photos of the pattern of the 360 cases (maybe I missed them, I'll go back and look). Love the water pump configuration, being an integergral part of the crank assembility rather than an after thought on the side.
Forum whore
All this foundry stuff is great, here is some more from Aus its car stuff but pretty interesting all the same
http://www.dmdaustralia.com.au/block.html
My neighbours diary says I have boundary issues
Forum whore
Yep ....."The factory team"
Those nights working on the EFI 2T catching up with you Rob?
Here is a home foundry, 60L drum with rockwool lined inside. Burner is powered by Tellus and fueled by Ethanol ( with a hint of castor ). Crucible, ceramic type. Gravity is the fuel pump.
Ready to pour, safety is my middle name! Fire is from magnesium powder poured onto the risers
The finished item
Ready to fly
"Waterglass" sodium silicate.
a decent chemist might have it the oldies used to use it for preserving eggs or something.
From what i understand it is possible to harden it by heating it in a dirty oven.
http://www.metcast.com/index.php/san...sodasil-g.html
Add some to Budha's oil....
Potters us in in glazes (i think) most of the pottery supply places have it.
http://www.pottersclay.co.nz/rawmat.htm
Just some random shots of uniflow cores and castings, this one is a 650cc
The cores are exhaust port and water cooling ( on the exhaust side ).This is a porting tool!
[IMG][/IMG]
First there was this[IMG][/IMG]
And then this[IMG][/IMG]
Then after pouring a mould I cut and changed the shape to the curve I wanted[IMG][/IMG]
Then a female mould made to make more replicas[IMG][/IMG]
[IMG][/IMG]
[IMG][/IMG]
The exhaust core is taking shape.[IMG][/IMG]
This mould will be the sand core eventually, so this shape will be replicated in hard sand.
Where you don't want metal, you need sand ( a core ). This is what's called a core box.
To build a pattern like this you start with the cores first.
[IMG][/IMG]
Green stuff is bondi fill, just mix it up and press the part you want to copy into it. MUST wax the male part first.
White stuff is casting resin, two pot mix. Sets with a faithful size, no shrinkage or expansion.[IMG][/IMG]
Cylinder mould building is slow, due to lack of time available. I had to change the main core mould to allow for these dimples to be made in the cylinder core. These are needed to fit ( glue ) the transfer cores to. Transfer cores not made yet. Evantually we want a hard sand core that looks like this.
The begining of the water core ( master ), this will be the same mould for top and bottom half, sand cores glued together in the mould.
Core prints need to be added to hold the core in place as the metal is pored. These will end up being the water inlet ports.
These are what " frost plugs" are on a car engine, not actually for frost, they are there to hold the water jacket sand core in place as the metal is poored around it. Also allows gas to escape as the air in the core expands as the hot metal is surrounding the sand core.
Orange things are air gun pellets, gives me a standard thickness on curved surfaces.Enter the transfer port master and transfer core box.
Water core box next, then all will become clear, as to how it all fits together.
Right, water core is done.
And poured a cylinder resin core copy
copies of the transfer port
Next I will be building the actual pattern, with these parts inside. Core prints will stick out of the final pattern ( thats all the tapered bits you can see on the ends of everything. It will become clear.
And all together
Starting to build the outside shape, beads and bondi fill. Beads are stuck on with a hot glue gun, real pattern makers don't use a hot glue gun, apparently. Or for that matter, plastic beads.Ok, it was crapy glue anyway. I'm not sure is the real answer. I am concidering a YZ125 as a base but either way I'll need to re make the cases as the transfer port arrangement won't suit. Also I'm not sure anyone has noticed yet but this cylinder is not an FOS type, although it may look like it. There is an extra part I haven't shown yet, see below. Remember it's a uniflow scavange type, with one piston.
OK now I've shown the missing part, let the "debate" begin.
[IMG][/IMG]
The beads and bondi fill are spreading.
SVC cylinder is getting close, now the slow finnishing process, painting and sanding. Still have to sort out round the exhaust.
And around the water core prints, this is where the cooling water will be directed into the cylinder.
Top four screw lugs are for holding the head water jacket on only, not the head itself.Cheated a bit today, I 3D machined this core box in aluminium. The wood one could be used no problem but I've found that cores , like the water one, that have a lot of exposed surface area to the molten aluminium can cause venting trouble. Cores made in a hot mould ( shell moulding sand ) are far better at venting hot gases out through the core prints and not into the molten aluminium.
Off to the foundry this weekend but I don't think I'll get this cylinder cast, still needs a few nights of finishing and tidying, I'm just concentrating on the 360 cases. Probably take a day off next week and have crack at it.
You should be so lucky, the F9 used to drink 200L drums of ethanol. I think it thought I had my own private still.
A couple of sand cores from the alloy die. These will be used in the moulding /casting next week.
Black stuff is carbon from the accetylene tourch, good non stick surface.
You can see how the core prints ( sticky out bits ) will hold the sand core in position to allow metal to flow around the core. When the metal has solidified the sand bond is destoyed and the sand pours out of the holes left behind by the core prints, leaving a water cooling cavity. You will see.Foundry day was successful, 360 cases cast. Need to tidy them up, send off to get heat treated ( CC601 ) to T6. Casting is to suit YZ 250T gearbox. This is the engine that will have the computer controlled throttle via the rotary valve timing gibb ( slide ). Will run on E85. Cases are water cooled via the cavity behind the RV and under the crank case where the engine mount runs. Reverse cylinder and crank rotation.
Patterns milled out on the CNC.
Reverse is via counter shaft ( gear drive ) also doubles as the ballance shaft.
Rob, Don't give up, it's the pain we all have to go through.Frits, somtimes a balance shaft is a necessity, I would be frightened to even get off the ground with this engine before the balance shaft was fitted, now I'd be happy to fly all day.
Sand cores multipling in Claire's oven, as time permits, during the day when she is at work.
Copied the bondi fill transfer core box into metal at the foundry this week end, so now I can make hot sand cores. If I was interested in production I would have made a few more metal die copies but I probably will only ever need 12 transfer sand cores? One casting to machine up first and make mistakes on and the second "real" one.
Grinding the sleeve, fixture has been made to hold the sleeve evenly all around.
This is what happens when Flettner has no freeview.Off to the foundry tomorrow
Sleeve with piston. Sleeve ready for nitriding.
Foundry day successful.
From glue, beads and bodifill rubbish, to somthing usefull.All I had time for tonight, four threads on top are not head studs. Both cylinders have been heat treated but I'll only machine one, untill there is a mistake!
This appears to be a very clean casting, must have had the risers ( feeders ) in the right place.
Machining out the 360 cases. CC601 heat treated usualy machines well, shiny and hard.All finished, just need a crank case and head to screw on.
Possibly already shown this photo? The 360 cases ready to machine, heat treated to T6. right hand case is nearly finish machined now.
Should find some cases for the sleeve cylinder in here somwhere.
Here is a sad looking 350 cylinder. The problem with using an original to copy from is the surface finish. You will need to polish the fins smooth, with no undulations as the taper is so slight that it takes very little of a blemish to hook up and break the sand copy ( mould ). Better off to build each fin layer by layer, that way its easy to access the surfaces as you build the pattern up. Note the gaps in the fins , these were always said to be there to aid cooling, crap, these are there to offer some support from sand fin to sand fin ( sand mould strength ). You just have to see things in reverse all the time, funny thing, I somtimes have trouble seeing things the right way round!
Forum whore
Tonights efforts.
Red line is my best with a carb on this cylinder, Blue line is where I am at now with the EFI.
There must have been some software setting I was getting wrong.
I am not sure what happened, but for a couple of weeks we have been struggling with the map table and trying to get it to run well and all the time the Beast has been a fussy pig.
Not knowing what good looked like I struggled on with a bad setup.
In desperation I switched the second injector off in the software and the engine started to run realy good, not at all fussy and easy to change the map and best of all I could instantly go to WOT at 4kish and it would pull away without fuss until it ran out of injector time around 12.
Although the secondary injectors were switched off they still showed up on the gauges, no doubt the problem was something simple, I am sure Matt from Ecotrons will put me straight.
I was close to giving up, but once the Beast started to run and I saw how easy it was to make changes with the map table I have to say I am getting excited about EFI again.
Forum whore
Way to go Neil.
How are you going to accomplish that? Teethed Belt?Reverse cylinder and crank rotation.
Forum whore
Patterns milled out on the CNC.
Reverse is via counter shaft ( gear drive ) also doubles as the ballance shaft.
Rob, Don't give up, it's the pain we all have to go through.
Anorak
Neil the Honda NSR125 Balance shaft set up is real neat.
Design lends itself to a real neat idler shaft
Kinky is using a feather. Perverted is using the whole chicken
Forum whore
A balance shaft is always a good idea, but putting your total power through the balance shaft's gear drive will lose you an unnecessary 5% of that total power
(which will heat up the cases, which will lose you still more power). And there is no need to run the crankshaft backwards because of your reversed cylinder.
Forum whore
It depresses me to think it took two weeks to twig to this but :-
I think I have fallen into a trap made by computer geeks.
Where in the virtual world of computer programing the logical numbering system starts at 0 not 1 like in the world of real things.
Its like this because in the real world you can have nothing and 0 means nothing but in the computer world an array position always contains something even if its nothing ......so 0 means the first position in a single dimension array, 1 is the second position and 2 is the third.
0,0 is the first position in a two dimensional array while 0,1 is the position next door and 1,0 is the other neighboring position to 0,0 and 1,1 is above 0,0 and between 1,0 and 0,1, nerd talk but you get the picture.
Apparently Ecotrons allows for 3 injectors per cylinder.
And I am beginning to think you can see the first one in the main screen and the other two labelled injector 1 and injector 2 in the advanced calibrations screen.
It is starting to look like.
0 = injector 1 on the main screen or the first logical item in a 1 dimensional array of three elements
1 = injector 1 in the advanced calibration screen or the second logical item
2 = injector 2 in the advanced calibration screen for the third logical item
Geek World ... Real World
0 = 1
1 = 2
2 = 3
so
0 = real Injector 1
1 = real Injector 2
2 = real Injector 3
Its simple really ......
So now I think I may have been confusing "logical" injector 1 with "real" injector 1, maybe logical injector 1 is actually real injector 2.
If this is the case it would explain the problems I have been having.
I have emailed Ecotrons support for clarification.
If that is not the answer, I will just have to fall back on my refined problem solving skills.
Will let you know.
Weekend cruiser
There are only 10 kinds of people in the world.
Those that understand binary notation, and those that don't !!!
Forum whore
10 binary = 2 real ......
Weekend cruiser
It's very easy to remember
10 to the base 2 = 2 to the base 10
Forum whore
Frits, somtimes a balance shaft is a necessity, I would be frightened to even get off the ground with this engine before the balance shaft was fitted, now I'd be happy to fly all day.
L-Plate Rider
Great dyno session on the FXR/FZR tonight. Mikuni TM33, Ross racing Piston and Kelford cams. Still a rough spot at 7000rpm, but likely to be exhaust length. 71 runs on the Dyno with a very patient Rob.
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