Surfacing a cylinder head

[AlisoBob]

Roosty knows the proper way to do it.

[Roostius_Maximus]

The CBN surfacer is thee only way to accomplish the finish reccomended by the gasket makers

[glen howell]

123

[glen howell]

123

[AlisoBob]

Glen, why wouldnt you turn the gasket surface on the lathe as well?

[glen howell]

It's actually better but I didn't say that.Glen

[M.F.D.B.]

Well I sure as hell am no expert, but I have a little experience on the metal lathe and they never seem to cut perfectly smooth. No matter how many "sweeps" we did you could still "see" a slight irregularity even tho you couldnt "feel" it. Im sure the granite slab with wet dry (I personally use plate glass as I havnt found a good chunk of granite yet).

If I had to choose ONE tool as I couldnt have both I would certainly choose the lathe, it can do way more than mill.

If I had both tools I would mill heads on the mill and then cut the chamber with the lathe.

If I was milling cr500 heads I would use the mill, but register off the head bolts like Glen does on the lathe, my guess is Honda most likely does it this way as the motor mount and spark plug both have odd angles. This would insure that the head bolts and head surface are perfectly parallel which also insures even pressure on each surface once torqued in place. This also means that going from the mill and then registering on the lathe to cut the chamber will be consistent since both operations register off the same surface.

No?

[kball1313]

I went old school the other day to fix some lousy machining on a CRF50 big bore jug.

Dragged out the iron lapping plate and went to town on it. I actually had to cut it down a fair bit and it worked sweet. I showed roostius the pictures of it haha. I only did it because it took me less time to lap it than set it up in the Rottler surfacer.

http://www.luthraprecision.com/lapping-plates.html

[blownbillybob]

you wound need a PCBN or PCD tool bit to get that mirror finish on the head surface the problem with the lathe is as your cut gets closer to the center your speed-feed rate changes and you could end up with two different finishes were as the mill speed-feed rate dosent change it stays the same across the surface

i finish my heads with 1500 on a granite plate

i need to make a nice fixture like roostys for my CBN milling machine but been to busy to do any of my own shit i havent even had time to assemble my top end on my '00 motor, but i do have to make some new swing arm extensions for my kids cr80, the races are coming fast!!!!!

[M.F.D.B.]

Just a reminder, when you mill the head, your head stay bolt alignment will change. In my cr250 I had to enlarge the holes quite a bit to get the bolts through...

[2strokeforever]

as long as it dosent leak it dosent matter to me

[eyesky2002]

Roosty knows the proper way to do it.

Is that head for a stroker engine? Looks a lot like how the head was done by E Gorr on a KX103 stroker I have work on for a local racer.