Head milling - For YT175

[RubberSalt]

I aquired an old. REALLY OLD (1940s old) drill press the week before last. Well, I decided to put it to use as a mill. This is my first attempt, it appears successful so far. I also attempted aluminum welding(fail!) on this head before lol

I grabbed my buddy (spywell on the forums) X Y axis Vise and got to work.

First things first. Being I cheat at everything I do, I used the milling bit in the bit to level out the cylinder head in the vise. I moved it back and forth and watched it ever so closely try to drag on the head. Everything looked square. I grabbed my can of spray lube and got to work. I measured down on the head, .040.

Supplies:
Time (took me about 2 hours to mill)
Drill press (not the best tool but it works if you take your time and are careful)
Milling bit
XY Axis Vise
Lubricant
Sand paper(200-600+ grit)
Tape
Flat surface(glass marble, granite)
Dishsoap/water
Beer

I started in the corner and moved to the bottom. It was more consistant and.. Smarter lol
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Almost done. I rushed this last part (Regretted it later!)
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End product!! it was smooth. Straight edge shows it being level. not nearly as rough as the picture makes it look.
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I taped some Wet/dry 220 grit sand paper to a sheet of glass. Sprayed some dishsoap/water on it and got to work. I made circles to remove material(figure 8 better when finishing)
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You can see where i rushed it and the spot i started in. it was a little bit deeper. I kept on lapping it...
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Woot!! the sand paper curled up. You can see the results near the bolt holes lol. I ended up taping all 4 sides down.
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I used 320 drit and then 400grit. This pictures is from the 400 Grit.
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This is 600 Grit. Almost a mirror finish.
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Compression is in!! I had 95psi prior to taking the head off, 105 psi with the new bore(high exhaust port). Im sure I lost some at the dunes when my intake ripped and I detonated !!

With my redneck milled head I have 130psi! :-D

[Dirtcrasher]

IDK if you have prior machining experiences.

Drill presses are not made for milling. They have sloppy tolerances and keeping the quill locked in position isn't very easy as well as the bearings are not intended for side pressure. Proper speeds and keeping items within a tight tolerance would be near impossible. Truth be told, I'd have no issue dealing with milling aluminum slots gently or that don't require tight tolerances. And your drill being so old is probably very sturdy.

I'm willing to bet if you indicated in that X/Y vise you'd see an issue as well as with the jaws. It does "look" good.

I guess all I'm saying is that I wouldn't use it for milling often or at all. But hey, we've all been in positions of "run what ya brung!!" But, I don't think my 1st project would be milling down a head.

Anyhow, it's not my business I just wanted to chime in and admit I did the same thing when I had no mill :D but now I never use it unless the Kurt vice isn't on my Bridgeport and indicated in. It's just so much sturdier.

Next thing I needed is a larger and newer lathe; There is just too much stuff I can't do with the one I have now. It's paid for itself.......

[RubberSalt]

I read up on the lateral pressures, and i went very slow and carefully due to it lol

Its definatly study, but there is an insane amount of up and down plan on that old thing, no side to side :). ** drill press cost $75

Imma purchase a digital angle gauge soon.

I'll bolt it up tonight and see what pressures i get. I fire it up probably saturday and check for leaks when the sun is out. Neighbors might get a little pissy.

[RubberSalt]

I updated the original post. But for those who don't want to read all that. I went from 95 psi to 130 :-D.

[RubberSalt]

Rode the YT today for a test drive. Seat of the pants dyno says... WOOOO!!!! It sure has gobs more power. Revs much faster. From idle to wide open, it is flying!! :)

I was going to cut a YT125 head tonight, but I may just pull that 175 head off and cut it some more !! lol

150psi would be nice :)

[jeswinehart]

No matter what tools used, a HIGH confidence level is thee best thing to start with.

NICE work !

john

[Lil Earl]

i really like how that ended up from what that started with