Head Machining fixtures

[jbrandt01]

I worked as a CNC programmer and operator for a few years and still have access to the machines. Thankfully I've been away from doing mindless production work long enough that I have the desire to actually do something for myself again.

I guess I want to start with opening up a set of heads for 90.5's and see where that gets me. Ideally in the long run I'd like to try some porting but I'm limited to 3-axis vertical mills so I don't think I can get too wicked.

Does anybody care to share their jigs and fixturing for doing head work? I know most who do this stuff use manual mills, but a good deal of the setup should be similar. I'm fairly confident I can come up with something on my own, but why reinvent the wheel? Is there some type of handy chart with commonly used information in these processes anywhere?

[fusername]

Real shops just use a single flycutter bit to open the cylender

[Devastator]

When I opened up my heads on a CNC mill, I just clamped them to the table on the valve cover surface, and indicated each bore in to run the program. If you're talking about porting the intake ports, however, I can't help you as you;d have to have a 3d model or NURB to go by and use a reduced shank, long reach, ball endmill, in 3 axis interpolation mode. While I have the software to program such a thing, and the machines to run it, I have no idea what the finish shape should be.

[fusername]

to clamp it down, they use a HEAVY cast piece that clamps the valve cover surface to the table, its a big Y kinda deal that goes into the space from under the PR tube holes. the table has cutouts for the rocker sutds, you'd probably have to reove them.

[Devastator]

the table has cutouts for the rocker studs, you'd probably have to remove them.

You can put the rocker studs in the T-slots on the table or put the heads up on 1-2-3 blocks. Circular interpolation on a CNC mill generates a lot less cutting pressure than the, flycutter shaped, tool normally used.

[Steve Arndt]

I have angle plates that allow quick clamping at the same angle as the valve seats/guides. I can post some pics of those.

[Chris V]

I'd go straight to 101.1mm...That way thickwall 92's and 94's will work without modification...to run anything smaller a shim just needs to be fitted, or 'powersleeving'.

[Devastator]

I have angle plates that allow quick clamping at the same angle as the valve seats/guides. I can post some pics of those.

I'd like to see those....

[Chris V]

http://bugpatch.com/VWToolsCatalog/VWTo ... fault.aspx

[rubbachicken]

http://bugpatch.com/VWToolsCatalog/VWTo ... fault.aspx

i love this kind of stuff, for sale ad, showing how to make your own

[hugging corners]

Hello.
Plate over the the mill design
The tool should be able to press in for spring removal with chuck and moded socked jug.

[ProctorSilex]

jbrandt01, have you made a jig yet? Care to share your design? Thanks.

[andy198712]

i've been toying with a berg boring tool, yes i know!

i feel they work better for cases then for heads as with the case you can take small cuts and build up, but to flycut the head you have to take a very wide cut when at the base if that makes sense?

an upside down head fits its rocker studs in the T slots fine i found... yet to try the cases on my floor mounted pillar drill, its a nice unit, weight nearly 200kg. nice and solid!

what tyre of cutter are people using and what speed?