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View Full Version : Cylinder Head work on the Bridgeport ??



cuslog
04-13-2010, 01:02 PM
So, I'm a bit of a Hot Rodder, do a bit of nostalgia style drag racing.
I've got a small lathe and a Bridgeport clone mill.
Had a little "incident" awhile back and bent 4 valves, (big block chev, aluminum heads) so I'm replacing all the valves with new. I'm thinking that the seats should be "touched up".
Any of you guys out there gone the DIY route with cylinder heads on the Bridgeport ?
I've seen the type that use a pilot stem in the valve guide and a cutter that slips over the pilot stem to re-cut the valve seat. (Goodson was the MFR. I think).
Any of you guys ever use one of this type system, how did it work for you ? What did you think of it ?
Any particular brand better than others.
I know its probably cheaper to just let the engine shop touch them up for me but you know how it is; its always nice to learn something new and be able to say you did it yourself !:)

J. R. Williams
04-13-2010, 01:21 PM
Forget the BP for reworking the seats and go to the type with the stem inserted in the valve guide.

JRW

Willy
04-13-2010, 01:45 PM
I'll go along with what JR Williams said.
Hard to go wrong when you are registering the grinding stone on the valve guide.
Been a while but I remember using a Sioux valve seat grinder a lot, but that was 35 years ago. I do recollect not having any come-backs though. it always did a very nice seat.
I know it's always nice to do as much as possible in-house, but it's hard to justify the expense for just a handful of seats. Although you can always branch out a little and have it turn a profit by doing work for guys in your drag racing circle.
That reminds me...what's the schedule for Ashcroft this year?

kf2qd
04-13-2010, 02:07 PM
Right - put all those nice new parts in and then add all that grinding crap. Get a good set of Neway Cutters and it will do a much better job.

medwards
04-13-2010, 02:08 PM
Forget the BP for reworking the seats and go to the type with the stem inserted in the valve guide.

JRW

I'll go along with what JR Williams said.
Hard to go wrong when you are registering the grinding stone on the valve guide.
Been a while but I remember using a Sioux valve seat grinder a lot, but that was 35 years ago. I do recollect not having any come-backs though. it always did a very nice seat.
I know it's always nice to do as much as possible in-house, but it's hard to justify the expense for just a handful of seats. Although you can always branch out a little and have it turn a profit by doing work for guys in your drag racing circle.
That reminds me...what's the schedule for Ashcroft this year?

The Goodson system that cuslog mentioned above is registering the cutter from the valve guide. In fact, you can use existing sioux pilots if you have them. The downside is that the Goodson kit is ~$800. If you have the money for the kit and a 9x42 or larger mill I say go for it. You can find a lot more info at http://www.speedtalk.com/forum/. Do a search for "bridgeport", that will bring up a couple hours worth of reading.

The only advantage of a Serdi or Sunnen seat and guide machine over a bridgeport is setup speed. The quality of the valve job is only as good as the setup for any machine. You can turn out the same quality of work or better with the bridgeport as you can the $100K dedicated machine.

I built a cylinder head fixture for my mill to make doing cylinder head work easier. The head bolts up to the plate in the middle by the exhaust flange bolt holes or intake bolt holes. I can adjust for level along the X axis and then set the valve angle.
http://i112.photobucket.com/albums/n177/edwardsmt/CIMG0326.jpg

KIMFAB
04-13-2010, 02:14 PM
I have a couple of old Sioux stem inserted valve grinder units from back in the day. I just checked them and they seem a bit worn or I would have offered them to you.
This is definitely the way to go though. get everything lined up and just grind in quick increments and reface the stone often.
You can reface the stone for each angle that you grind but you're better off with a stone for each angle.
You will need the grinding units, the facing tool, a high speed driver (looks like a drill with a funny hex driver instead of a chuck) and a set of guides.

Willy
04-13-2010, 02:14 PM
Right - put all those nice new parts in and then add all that grinding crap. Get a good set of Neway Cutters and it will do a much better job.

I'll admit there's more than one way to skin a cat.
But anybody that grinds valve seats, valve faces, or hones a cylinder bore and doesn't do a thorough clean up shouldn't be allowed to work on a wheelbarrow.

chevy3755
04-13-2010, 03:43 PM
doesnt Goodson have a 3 way cutter to cut the three angles for the valve seat..............time i have.....not much of anything else.........

chevy3755
04-13-2010, 03:45 PM
by the way Medwards thats a very nice fixture to do head work on......

cuslog
04-13-2010, 03:52 PM
Thanks guys;
medwards;
$800 is more than I would have thought, still kind of an interesting idea. Thanks for the picture of your cylinder head fixture. I looked long and hard at a commercial one like that but at $2,600 and not knowing how well it would really work for head work, I didn't follow thru, thought about building my own as you have done but even just the materials are quite a few $
So how much head work do you do with that fixture, on your mill. Do you feel its as accurate as you can get from a professional shop with a Serdi ? Are you using the Goodson setup or something on your mill ?
Willy;
Ashcroft Old Time Drags are June 11 - 13 this year, my favorite race but I may not make it this year (connecting rods on backorder from Manley). :(

ADGO_Racing
04-13-2010, 04:32 PM
The Bridgeport will do a great job. We also use a CNC machining center. The usual automotive machine shop follows existing holes. The heads and blocks, etc are originally machined on CNC vertical and horizontal machining centers. It is somewhat time consuming, but really the only way to do the job right. After market shops are usually only dealing with .010-.060 of material removal, and for stock work, +/- .010 is probably close enough.

As I stated in a another thread, you would be amazed how far off things can be from the factory. If the bore is off .015" from the factory, setting up off of a worn bore could easily push that number out another .005-.010".

We only work from certain surfaces, after a clean up cut to get them square and parallel. Also only use a CNC mill or Bridgeport type mill to do the work. If you get your spindle centered and parallel to your valve guide hole, the mill will do a much better job than the loose setup of a valve guide machine. A valve guide machine is nothing more than a bench top drill press bolted to a heavy table and a fixture. All the tools are driven from flexible connection. It is fast, dirty and acceptable for stock work and maybe some mid range performance work. You can do a great job with them, but your time invested will be similar to that of setting up a mill.

medwards
04-13-2010, 05:00 PM
...So how much head work do you do with that fixture, on your mill. Do you feel its as accurate as you can get from a professional shop with a Serdi ? Are you using the Goodson setup or something on your mill ?
.....

I've done valve jobs on a set of buick v6 heads and a set of sbc heads. I do a lot of rocker pedestal machining to Yates/Ford heads for Jesel shaft mount rocker setups. With the fixture, it's much easier to setup a head than my previous shim, parallel and clamp disaster setups. I have about $250 in materials in the fixture.

The goodson tools in a bridgeport are absolutely as accurate. I have a friend with a serdi in his shop. My work measures as good on runout as the serdi does, it just takes me three times as long to do a set. Good rigid pilots and fresh valve guides are the biggest contributors to low runout. I've been borrowing the goodson tools from another friend. I haven't had to do enough work to justify buying a set of my own yet.

EVguru
04-14-2010, 04:09 AM
T&S originated the ball head tooling I think and they're cheaper than Goodson;

http://tnsmachines.com/500.html

A.K. Boomer
04-14-2010, 06:34 AM
Right - put all those nice new parts in and then add all that grinding crap. Get a good set of Neway Cutters and it will do a much better job.


Im totally with you on that, Neway (which is actually an old way now as i was using them 30 years ago)
are superior to "the grind" in the way that they don't wear out the pilot shaft or chatter around and stuff, all you do is apply slight pressure and twirl them by hand, keep a perfectly dressed stone near bye for a quick by hand finish if you want -- but I think you will find that when checking with prussion blue that its more of a false security that's really not needed.

There is no need to hook up some heavy high rpm drive unit and dress stones every other seat and throw grit all around your shop.

With neways you can put a high perf. 4 angle cut in no time...

531blackbanshee
04-14-2010, 04:03 PM
care must be taken when using neways as they will try to follow the worn seat.
stone holders have bearings and don't wear the pilots if all is in good order.

leon

bob308
04-14-2010, 04:46 PM
i have seen more head swrecked with neway cutters then any other. grinding is the most aucurite. cutters are the fastest. so take your pick fast or quick.

ADGO_Racing
04-14-2010, 06:09 PM
I have never had a problem with a cutter in the mill cutting a seat. I can see the myriad of ptoblems trying it in a modified drill press, like most guide and seat machines. But when taking the time to do it right in the mill, no problem. But as stated before, the results are only as good as the craftsmanship applied.

A.K. Boomer
04-15-2010, 10:03 AM
i have seen more head swrecked with neway cutters then any other. grinding is the most aucurite. cutters are the fastest. so take your pick fast or quick.


That's strange, Iv done hundreds and hundreds and never "wrecked" one of them, and in fact I would think it impossible unless you dropped the head on the floor with the cutter and guide in it and it landed on both ------- ?

All that's separating you from verification is a very thin layer of prussion blue,

The carbide cutters are staggard/offset so they don't set up a pattern,
Iv brought around round burnt valve seats in no time - if your cutter and guide fit are good (which they will be and they will remain that way due to them not being exposed to grit) then they will not "follow a worn seat"

Standard practice on the old VW was valve guide replacement BEFORE the valve job and the new guide was always "off" from the old - yet the neways totally brought the seats into center and you would watch it happen in the matter of a few turns, not so with stones as the Higher rpm's and grit eat at the guide and stone holder and you also need way more clearance even when there new so they don't Seize while in use....

anybody who says neways ruin heads simply don't know how to use them...

They are hands down superior.

pistonhead
08-21-2010, 01:00 PM
Is an old thread but I think I can contribute something new to the topic I also have been using Neway cutters for a long time, I have tried stones, the ball drive single blade insert thing and not had any luck, to tell you the truth I never used or tried any Serdis, because is out of my budget, but th resent changes on engines going ever so small and require more presicion, has force me to do something about it. I am still using Neway cutter heads but with a new twist... I make my own carbide blades, I grind in a 3 angle profile on them and I cut the 3 angles in one pass, just like a Serdi machine but with out the high cost, is no need for carbide pilots with this setup, is practically no deflection on pilot because the cutting pressure is distribuited on 5 blades, and the pilot is also suported on top by the driver, By the way I use a Kwik Way Head Shop seat and guide machine to do the machining, is no way it can be done by hand is to much load on the cutter with a 3 angle profile cut.
I leave some pics so you get an idea how is done www.new3acut.com
http://i921.photobucket.com/albums/ad56/headshop57/Blades28junio10034.jpg
http://i921.photobucket.com/albums/ad56/headshop57/42GM2005valvejob009.jpg
http://i921.photobucket.com/albums/ad56/headshop57/38fordvalveseatcutting009.jpg

pistonhead
08-21-2010, 03:35 PM
In case you are wondering , how to set up 5, 3 angle profile blades on e Neway cutter Head( 45 or 46 only) here are some pics:
http://i921.photobucket.com/albums/ad56/headshop57/38Fordvalveseatcutting2017.jpg
A tool setting fixture like this is a most, youn can getit from Goodson.
http://i921.photobucket.com/albums/ad56/headshop57/42GM2005valvejob016.jpg
Take a reading from the valve, where you want the top of seat angle to hit.
http://i921.photobucket.com/albums/ad56/headshop57/Blades28junio10048.jpg
Now just transfer this setting to blades, that's it.
http://i921.photobucket.com/albums/ad56/headshop57/42GM2005valvejob015.jpg
On the first cut you can check where the valve hits the seat with some very fine laping compound, no need to lap the rest of the seats, the seats are going to be very concentric, if your valve is good(concentric with in .001") it will seal and pull good vacuum. By the way that's another topic "how to turn your old valve grinder into a centerless high presicion valve grinder"

Willy
08-21-2010, 04:31 PM
Well Mr. "Pistonhead", your advice looks suspiciously like an ad to me.

Why don't you contact Village Press if you want to flog your merchandise here, I'm sure they can set up an ad for you properly rather than sneaking it under the door.

Rich Carlstedt
08-21-2010, 04:33 PM
Memories, Memories
Back in the 70's, I made tooling for a famous engine rebuilder.
Below is a picture of a valve seat boring,facing tool I use to make from 4140 hollow bar stock. ( this was a reject tool, so I kept it )
I am really impressed with the postings by pistonhead and A K boomer and they have it on the money.
As AK said, you do the valve guide first and it takes care of all the rest.
The tools I made were in all different Valve guide sizes and seat angles , and the angled tool bit hole was precisely controlled so preground toolbits could be inserted by the operators on the ....Bridgeports !
(Obviously, the HSS bit shown was not used on a head, but for a job in my shop)
The secret is good spindle bearings and a solid stop.
The work is then impecable
http://i273.photobucket.com/albums/jj220/StationarySteam/Shop%20Tools/P8210010.jpg