the HEADSMESS thread :o

HeadSmess

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making things. i like making things.

i guess i should just make my own thread of silly things ive made, for and related to the area of motorized bicycles.

good for me too cus ive never really catalogued or taken notes.

my harddrives a mess. random pics here there and everywhere...

so this is a bit of a kick up the :poop: chute for myself to get me off my butt and making these things.

ill also accept sensible suggestions within the realms of possibility. custom work...


so.


regards squish bands. i vaguely mentioned having some 80mm billet and a mill.


so, my results so far...


PICT0297 (Large).jpg

one hemisphere. so far so good. more of a semi hemi sphere... probably a radius of 18, and about 5 deep... so a slice of sphere... 2.2cm^3 apparently, if my labware can be trusted. eep. that is...lemme see... 2/3 of 48...32... way high. ima gunna blow! i need a tighter hemisphere me thinks :( more volume!


um... been stuffing round trying to cut fins today. went for 8mm cutter. try out a new plan on the next one :) takes a while to try out each layout.

but! 90 % finned...

PICT0321 (Large).jpg



went for a neato angled fin look :) ignore the four extra stud holes where the drawing messed me up... grrrr. 2mm out. grrr. it wasna me!


im hoping the mechanic has a standard plug tap. or a helicoil. or someone has one. cus i sure dont.

there may be a tapped hole in the centre but thats just cus the billet had a previous life... its wrong pitch, diameter, everything.

um. i can mill threads but it involves destroying a tap for a cutter and using a weird program with gremlins. but then they can be indexed.

until then theres not much more to add.

got a squish of about .65, seems pointless when the piston is chamfered at the edge, but hey... i tried matching the chamfer a lil bit? hard to do without recessing the head a bit, or shave cylinder. chamfer is deep, cylinder has a radius at the top edge. crown only just emerges from cylinder.

i do have to shave a cylinder down to the edge of the chamfer, but for now, im just looking to see what gains i get on a stock motor...

yes, its a 48 head. yes, ill be looking at making them on a regular basis. round, square, whatever. this is a trial only. play around with plug types as i get more taps. like D or C sizes...


part of the reason i was contemplating a water cooled head was that...its going to be painful holding this thing now the fins are cut... unless i make that jig i was contemplating to hold heads with. means a new head to try a different hemi... :(


next thing in the pipeline is a dyno of some sort. it will share one characteristic with real dynos...the readings wont be real figures but as a guideline only. simple alternator will do it :) big fat heavy load resistor, variable voltage to field windings, read current/voltage running through load resistor. raise voltage at field windings until the thing stalls :)


pipeline, pipeline... a two speed shift. not running through the derailleur.

chain tensioner bracket clamp thingy cus ive lost way too many spokes in the past due to that thing slipping.

a nikasil cylinder. surely its possible?

a water cooled head cus i got a lil baby radiator and water pumps can be made easily.

more tuned pipes of various rpm.


erm. its finished while writing this...

PICT0326 (Large).jpg


heh heh heh. i fore see detonation, a nasty peaky powerband, clutch slip when starting, and overheating :) it really wont like my pipe! guess i find out in a day or two.


:freak: :sneaky:
 
That sure looks good with the angled fins, but I'm thinking that will restrict airflow and overheat... just my opinion. Everything great started out with someone's tinkering. As for the nikasil cylinder, I know Ford has had great success with it, and it has to wear better than that crappy plating the chinese use, probably better for the environment, too. I'll be first in line for one when you git er done!
 
over heating? no idea. only just tapped the thread out and assembled it. gave it a blip down the road and it was screaming! top of cylinder seemed to get hotter than the head... then the carb came off :giggle:

very nice pattern left from the transfers. this is really calling for the clear plastic head and some smoke signals to determine whats really going on in there...

starting was easier than contemplated. can still "kick" start it :) idles nice and smooth.


time for the real test ride!


cylinder lining technology is a strange area. rotors for example. german invention. they got to the point of hard chrome plating. which then required special seals. which led to chattering and chrome chipping. this spelled the demise of NSU... chrome plating can come off in big sheets. that happened with the...suzuki(?) rotaries. i believe the nortons are prone to it to.

but the japanese are never deterred by seemingly insurmountable obstacles! talking with a guy thats been developing a single rotor for aircraft, they take a whole new approach now (rx8)... high silicon/carbon alloy. cast it. rough machine to size. heat treat so that carbon and silicon precipitates to the inside of the cylinder (or epitrochoid if youre still in rotor land). the silicon combines with the carbon, forming silicon carbide, one of the hardest manmade materials around. these crystals of SiC are growing from the alloy itself. they cant fall off or be dislodged!

the SiC is then diamond honed down to finish size. then its finely honed with a softer material to
1, round of the sharp edges on the Sic crystals.
2, relieve the crystal from the surrounding alloy.

you get a microscopic surface that vaguely resembles the wild west. lots of "steppes" and "buttes" with valleys in between...

you then end up with a permanent, indestructible, hard wearing surface that retains oil for lubrication! (mmmm, grand canyon full of oil...)

and, in the case of rotors, can go back to plain steel seals without chattering :)


unfortunately this requires casting new cylinders, and a pretty sexy heat treating facility. read induction furnace, on controlled cycle for roughly 48 hours... and some other specialised equipment.

back to the head... looking through various sites, ive seen billet heads with what looks like less finning than i have here... oh well!

personally id prefer some 100*100 flat bar instead of the round billet, but hey...whats on hand, whats on hand...
 
stupid "whats on hand"

i need more fins :(

goes like a rocket :) until it heats up :eek:

oh my.

i melted an electrode :giggle: ceramics dark? electrodes melted. cool :)

changed plug and still...auto ignition :) maybe not a good thing? it definitely kills all bottom end :(

could run the baby on diesel! cus i guess the 91 isnt too good for it either :giggle:

so. i guess i have to use a 6mm cutter and make more fins this time round.

weeee! i shall be back:sick:


theres another approach still... make an insert for a standard head... got some 58mm billet too :)
 
Only going by comparison between the difference in cooling surface area of your cylinder head and the CR Machine Manufacturing cylinder head, you will need a heck of a lot more cooling fins to be somewhere equivalent.
 
yeah once you make another with more fins then it will be good.
keep in mind that the most important thing for cooling is the total surface area of the head that is exposed to air.
since it is difficult to make a head with fins you could cheat and make it wider and longer for more fin area.
or groove a finless head and slide sheets of aluminum into the grooves and then use a flame type welder to tac the "fins" in place. that way you can have many thin fins.
 
it gets worse :)

i was fighting conflicting requirements... i originally intended on using a 6mm cutter but went for an 8 cus it can cut deeper and faster... thats a large reduction in fins itself. youll see my drawing on your squish thread has twice the fin area of this... i should have stuck with that pattern :eek:

i had no other material on hand. i have four pieces of this alloy. 75mmx32mm

so. insert a standard head. just recess it to take a machined insert. theres always heat transfer issues using a join, no matter what. i dont like it. anything but a welded join is suspect in my mind.

find a heavy duty heat sink. shame the one section i have here is 10mm too narrow. would be bewdiful :)


do the fins with a parting tool, RC car style... not much height but id get a few in.

finish this one...


PICT0333 (Medium).JPG


:giggle:

this reminds me i have to ring that b4$t4rd that promised me a metre of 600 channel iron to put my mill in! its filthy! i need coolant! then i can run these cutters harder!
 
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