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Fri May 10, 2024 10:11 am

MrVWGuy wrote: I used the KE-55 CNC mill because it is what I have access to. It is a piece of equipment on the shop floor of the company I am a manufacturing engineer for. I designed the fixture and my buddy milled it from a couple scrap pieces we had laying around. As guessed, he wrote a canned program and once the fixture was made, it made quick work with excellent results, and I have the fixture for future builds. Yes, a lathe would have made more sense but I don't personally have access to one. We did this at work on a Sunday morning when the shop was empty, a benefit of my job that I've used many times over the years. Here's a video if you care to watch:

https://youtube.com/shorts/sE3h8iUubGc?si=19i7QSEuAmQYFgFJ

That's the real answer right there, it's depends on what you have access to!
I miss being able to run stuff on the CNC but I no longer have access to one.

Would I like to have access to one - absolutely!
Do I want to own one- hell no!

Fri May 10, 2024 10:50 am

If you wnt to do pushrods in a mill, lay them in the vise horizontal, stop on one side of vise to butt them against, mill other end to length close to vise edge with side of end mill, make one clean up cut, measure, take remaining stock to length, put next rod in vise and against stop and cut to the same numbers/dial reading, length control on a lathe is tricky if you don't have a stop in the spindle, cut, measure, pick up end with tool again, dial in remaining amount, cut, repeat 8 times. Downside of a mill is you still have to counter sink/ deburr the hole for the end which can be done by hand or back in the lathe.

Fri May 10, 2024 11:00 am

I like to play a game where I see how many I can do at once and how fast I can trim a full set to within a few thousandths of my target length. :D These are tapered so that cast square behind it is just bracing the tapered section so it doesn't chatter.

Fri May 10, 2024 4:49 pm

Nice, use the stop for the support, and the angle plate for the stop!

Sat May 11, 2024 9:37 am

it took $134, probably 10 hours of work, and a complete parts donor from a guy on one of the machinist facebook groups, but I now have a working criterion 3f-hb facing head!

the one I bought had a bad worm screw and gear that drives the facing function. the C clip was missing, so the clutch springs pushed the gear out of alignment, causing the thrust washer to ride the worm screw, which damaged it, which then damaged the gear.

the donor had a bent clutch housing, caused by a problem that both copies had: the cap that closes off the holes to where the boring bars attach got pushed up - presumably by bottoming out the bar. that caused the clutch to very stiff, so the facing gears would just spin. it would work with the screw, but not the hand wheel. and it was missing the plastic pin for the drive screw.

the later style head has the top milled off the clutch housing, which at least kept the head from being damaged (it would still get stiff).

oh, and the screws that hold the hand ring assembly on. there are TWO different lengths. the short screws go along the screw/clutch axis, the long screws go across. the short screws are blue, long are silver, in my picture. if you put the long screws in the short holes.....guess what. they hit the clutch! and the screw head.

the rest of it was figuring out the right way to put the clutch together - both of them...varied.

from the housing end to the gear end - ball, spring, tapered pin. tapered end of the pin goes toward the gear (it grabs the gear holder ring).

the other obvious change between the two heads is that the gib switched from a push to a pull - I can see the old version eventually wearing out and breaking off.

I think anyone using one of these should take care to recognize the problems caused by bottoming the bars out.

more pics in the gallery - https://www.thesamba.com/vw/forum/album_search.php...t_dir=DESC

oh and one other note:

getting the shaft off of these.....the R8 shaft came off by putting it in the mill, switching to the back gear and leaving the spindle locked (dont lift). added some brake for good measure, and had to tighten the drawbar a few times. tightened the gib screws, put a ~10" bar into the horizontal bore hole, and smacked it a few times with a deadblow. came right off.

the straight shaft on the other unit had been, by appearances, epoxyed in. not even red loctite. I ended up just milling pockets over the top of the screws to be able to get them out...... I didn't want to torch the thing to try to loosen the epoxy. if I wanted to switch to the straight shaft, I'd have to swap the top assembly over with it (or torch it off now that it's not attached to the head).

Sat May 11, 2024 2:46 pm

Good job,
You may be able to get parts, however Criterion got bought out,

Sat May 11, 2024 8:08 pm

RWK wrote: Good job,
You may be able to get parts, however Criterion got bought out,

thats where I started - allied said absolutely nothing available. that led to a few community posts to see if anyone had fab'd the worm+gear, and a few folks offered but it was 4 figures, and one guy had some made years before but couldn't find them.......and then the donor head happened. :)

Sun May 12, 2024 7:23 am

Looks like someone crashed that gear - :shock:

But if you get it working, you will enjoy.

I am just amazed how many have upped their game w/ machining VW parts. I am happy to see it. I remember early part of 2003 -when I came on here - i must have looked like w/ 3-heads when I showed a boring/facing head. My first one was same model Criterion. And I also have the 3-inch Criterion boring head for most major work as I only used the facing head for the one purpose -facing the sealing surfaces in the heads. Other than that job - I never brought it out. It was expensive enough the first time -

Then came the Wohlhaupter UPA-3. The rest is history - I still have the Criterions -saved for other mills. I always keep the toolings of all my mills. I have tons of B&S #9 stuff as they are hard to find.

Very cool-guys.

Wed May 15, 2024 6:30 pm

fix the gears or make new ones....or find gears the right size gear and bush addapt it to your application.

Thu May 16, 2024 7:02 am

What do I have here? Some sort of grinding compound? Heavy as heck! Fine bead like structure.

Thu May 16, 2024 11:45 pm

I got something like that from my local coating place when i needed some blasting sand, they called it "steel sand", used it to blast my front brake backing plates, worked well. Not 100% sure that it is the same thing, but looks very similar.

Fri May 17, 2024 4:12 am

I will check it with a magnet.

Edit: Yes you can pick it up with a magnet!

Fri May 17, 2024 12:46 pm

shot peening/blasting /cleaning meida. the issue with it is getting it all out. Ive had people bringf me ballanced assys and the cranks shaft is full of that shit in the balance holes as well as threads and oil gallys.. Ive also gotten balanced new conecting rods with that stuck between the bolt head and the rod and even in threads. it sure is hard on threads. and how do you balance something thats packed with steel that will come out while running and eat up the oil pumpekinhousen?? you cant fix stupid.

Mon Jun 03, 2024 3:17 pm

- couple questions , i see everyone who has trimmed cylinders has used/made a aluminum plug for end support , any issues if its made of steel . gotta ask .

- need to also fly-cut heads ,any one have any good pictures of securing it to mill bed .please post them so i can take it with me .

- and finally any other options for flycutting beside cnc method which is super cool , and or boring head tool

thanks guys

Mon Jun 03, 2024 4:44 pm

You don't need a stepped plug for trimming the cylinders, a flat plate with a center hole will also work. Just press the base of the cylinder into the chuck, and it will square it all up. You will only be taking light cuts anyways.

Other than a boring/facing head, or CNC machine, you could use a rotary table, or build a face plate for the lathe, but those are both awkward and time consuming. Guys do have success using Berg style single blade cutters, but I have found they will take off .025" when you were hoping for only .005" removed, and the chatter is totally unpredictable, and usually excessive. Single blade plunge cutters are far from precise.

Brian

Mon Jun 03, 2024 5:52 pm

Right, just a big washer will work. I've done many motorcycles cylinders that way. It will center itself.
I made special washers for 92 and 94 bore, only because I expect to get enough uses out of it to be worthwhile, and to reduce the whole lower diameter when needed, to make 92 and 94 slip in to smaller case bores.

Look here: When we tried to teach chickensoup how to bore stuff.
https://www.thesamba.com/vw/forum/viewtopic.php?t=...mp;start=0

My cheap boring head is still working great, I've done a LOT of jobs with it, with the carbide tool bits, the HHS tool bits wore out far too fast for my liking.

Mon Jun 03, 2024 10:22 pm

Great link modok
And great info guys

Tue Jun 04, 2024 6:19 am

Mine is alum, mainly because I had it, it's easy to machine, won't scuff the cylinder, the step is easy, why not, make step .002 under bore, adds rigidity and some safety.

If you don't have a fixture to hold head, the easiest way would be to clamp something inside each exhaust port, a round bar or a round nose strap clamp will work, regardless something will have to be made to hold it down, exhaust ports are in line so it's an easy set up to the T slot.
This is my dedicated fixture, bolts to mill table, see SHCS near ends, can bolt head thru pushrod tube holes and a small wedge clamp to intake port lip, (won't work on AM heads) or I use the exhaust port method, see end holes, other holes clear rocker studs, valves if installed, ect.

Tue Jun 04, 2024 6:36 am

has anyone used this from rocky

Tue Jun 04, 2024 11:05 am

jim martin wrote: has anyone used this from rocky

Same as a Berg cutter. I made mine just like it years ago. It will work fine for boring cases, and boring the heads larger, but they suck for fly cutting the quench surface in heads. I could get 3 bores to cut nice, and then it would wad up and chatter on the last hole. Or if you need .005" cut, it wing off .025" off before you know it. It's too broad of a cut to try and make in one pass.

Modok has mentioned he had better luck with carbide than HSS, so that might be a chance. I just gave up fly cutting with them, and bought a real facing head. Now I can take .002" off all 4 holes and they all come out like glass, and all exactly the same. The single blade plunge cutters really are a bastard way to cut. They are the same as taking a .625" pass in the lathe, full width of your cutter, and not expecting it to chatter, bog, and gall up the tool.

Brian