Aluminum cylinder head surface finish help(pics)
Close
Login to Your Account
Page 1 of 3 123 LastLast
Results 1 to 20 of 55
  1. #1
    Join Date
    May 2013
    Location
    South Africa
    Posts
    8
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default Aluminum cylinder head surface finish help(pics)

    Hey guys ive just started getting into machining etc and ive got a fabricated fly cutter with a single PCD insert and i cant seem to get a good surface finish

    ive made this cutter to surface cylinder heads and need a super smooth finish but i keep getting lines on the surface.

    any help will be greatly appreciated!

    i have attached some pics so you can get a idea as to the finish..

    thanks

    Lee
    Attached Thumbnails Attached Thumbnails 20130614_153403.jpg   20130614_153407_1.jpg   20130614_153410.jpg   20130614_153414.jpg   20130614_153433.jpg  


  2. #2
    Join Date
    May 2013
    Location
    South Africa
    Posts
    8
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    forgot to add the pics of the cutter...

    it uses a RNG insert which has quite a sharp edge.
    Attached Thumbnails Attached Thumbnails img-20130614-00047.jpg   img-20130614-00045.jpg   img-20130615-00049.jpg  

  3. #3
    Join Date
    Aug 2005
    Location
    Tucson AZ
    Posts
    6,449
    Post Thanks / Like
    Likes (Given)
    9896
    Likes (Received)
    3034

    Default

    Not enough info to give an answer? What machine? You cannot do this on a turret mill. Plus an auto motive shop could do that for less than you paid for that insert.

    I see from you second pics that it appears to be in a VMC. How is the work held? Depth of cut?

  4. #4
    Join Date
    Jun 2012
    Country
    UNITED STATES
    State/Province
    Idaho
    Posts
    3,177
    Post Thanks / Like
    Likes (Given)
    1756
    Likes (Received)
    2084

    Default

    If you just need a flat surface,,belt sander be faster,cheaper and better than your Fly cutting.

  5. Likes cg285, JoeE. liked this post
  6. #5
    Join Date
    Apr 2009
    Location
    Beaver County Alb. Canada
    Posts
    1,876
    Post Thanks / Like
    Likes (Given)
    542
    Likes (Received)
    922

    Default

    Looks like your using a Round insert, for Alum. I would use the appropriate insert. Sharp- pos. rake,if your using a insert not designed for Alum. you will have to really crank up the RPM"s and your setup will have to be rigid! Redirect Notice
    A properly ground and honed HSS tool in a "FlyCutter will also work well. Practice on some pieces of Alum. before its to late for your Head. Or as TDmidget says get someone to do it , cheaper than buying new heads!!!!

  7. #6
    Join Date
    Apr 2005
    Location
    Beaverdam, Virginia
    Posts
    8,121
    Post Thanks / Like
    Likes (Given)
    914
    Likes (Received)
    3904

    Default

    Quote Originally Posted by redlee View Post
    Looks like your using a Round insert, for Alum. I would use the appropriate insert. Sharp- pos. rake,if your using a insert not designed for Alum. you will have to really crank up the RPM"s and your setup will have to be rigid! Redirect Notice
    A properly ground and honed HSS tool in a "FlyCutter will also work well. Practice on some pieces of Alum. before its to late for your Head.
    +1 on the sharp tool and are you using flood coolant or at least blowing the chips off as you cut. I have a feeling you are taking too shallow a cut, you must at least go deeper than the radius on the tool. Redlee is that an old mid 60's Dodge window van in your avatar? I had one too when I was in my late teens 35 years ago.

  8. #7
    Join Date
    Feb 2013
    Location
    Syracuse, NY, USA
    Posts
    106
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    13

    Default

    I'd use HSS and hone the edge. Also, cast aluminum cuts differently than rolled. Also, you can use Crisco shortening for coolant, but it gets messy.

  9. #8
    Join Date
    May 2013
    Location
    South Africa
    Posts
    8
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    Quote Originally Posted by tdmidget View Post
    Not enough info to give an answer? What machine? You cannot do this on a turret mill. Plus an auto motive shop could do that for less than you paid for that insert.

    I see from you second pics that it appears to be in a VMC. How is the work held? Depth of cut?
    Hi tdmidget its fexac universal milling machine. i has a variable spindle and table traverse. spindle up to 1800rpm. depth of cut is probably. +- 0.01mm

    this particular head has the tappet cover surface parallel with the gasket surface.

    im trying to start up a small shop doing surfacing , porting, seat cutting etc on heads so trying to keep everything "in house".

  10. #9
    Join Date
    May 2013
    Location
    South Africa
    Posts
    8
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    Quote Originally Posted by redlee View Post
    Looks like your using a Round insert, for Alum. I would use the appropriate insert. Sharp- pos. rake,if your using a insert not designed for Alum. you will have to really crank up the RPM"s and your setup will have to be rigid! Redirect Notice
    A properly ground and honed HSS tool in a "FlyCutter will also work well. Practice on some pieces of Alum. before its to late for your Head. Or as TDmidget says get someone to do it , cheaper than buying new heads!!!!
    hey redlee most of the bigger dedicated surfacing machines are using these inserts with no problems so im stuck..

    my insert does have a very sharp edge, do you think a more rounded edge would be better?

    thanks

  11. #10
    Join Date
    May 2013
    Location
    South Africa
    Posts
    8
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default

    what ive tried so far:

    tramming the head
    played around with spindle speeds from 500- 1750rpm
    table feeds from 11 - 500 mm/min
    depth of cut 0.01-1mm

  12. #11
    Join Date
    Jan 2007
    Country
    UNITED STATES
    State/Province
    Florida
    Posts
    1,181
    Post Thanks / Like
    Likes (Given)
    146
    Likes (Received)
    427

    Default

    are these typically o/h cam heads and what is the primary reason for surfacing?

  13. #12
    Join Date
    Jul 2009
    Location
    Peoria, IL
    Posts
    11,738
    Post Thanks / Like
    Likes (Given)
    51
    Likes (Received)
    9003

    Default

    Quote Originally Posted by Dave1123 View Post
    I'd use HSS and hone the edge. Also, cast aluminum cuts differently than rolled. Also, you can use Crisco shortening for coolant, but it gets messy.
    I'll just hope that is a joke.


    Ditch the button insert. Too much tool pressure. Get a regular 90 degree insert like a CNMG. You can get them in PCD.

    You need to check that the inserts are both at the same height. It's a homebrew cutter, so you probably need some adjustment.

    Try something like WD40 if you don't have coolant. Around 1500 RPM. PCD can handle the SFM.

    What kind of feed do you have? You need a consistent feed rate.

  14. #13
    Join Date
    Dec 2008
    Location
    Delaware, USA
    Posts
    200
    Post Thanks / Like
    Likes (Given)
    5
    Likes (Received)
    30

    Default

    [SIZE=3]Don't use a belt sander ! They are fine for exhaust manifolds where you have a thick gasket. NOT good enough for cylinder heads.

    Your first pic shows the head vibrated at that end. How are you fixturing the head ?? Show pics. What kind of head is it?

    I do cylinder heads for a living. CBN cutter. ( Big flycutter- 2 round pucks ) no coolant. Finish pass is .001" -- .002" DOC . I spray the head with ZEP lube ( yellow can ) for finish pass.

    What kind of surface finish are you looking for. Too smooth is just as bad as tooo rough as far as head gasket is concerned. What [B]KIND[B] of head gasket is being used ?

    Ron

  15. Likes GregSY, Joe Rogers liked this post
  16. #14
    Join Date
    Mar 2007
    Location
    Milford,Ct
    Posts
    487
    Post Thanks / Like
    Likes (Given)
    438
    Likes (Received)
    109

    Default

    What surface finish does the manufacturer call out ? Most will call out a particular finish to work with the head gasket .So unless you know what you need you don't know if it is good or not .Bill

  17. Likes Joe Rogers liked this post
  18. #15
    Join Date
    Apr 2009
    Location
    Beaver County Alb. Canada
    Posts
    1,876
    Post Thanks / Like
    Likes (Given)
    542
    Likes (Received)
    922

    Default

    Quote Originally Posted by Dualkit View Post
    +1 on the sharp tool and are you using flood coolant or at least blowing the chips off as you cut. I have a feeling you are taking too shallow a cut, you must at least go deeper than the radius on the tool. Redlee is that an old mid 60's Dodge window van in your avatar? I had one too when I was in my late teens 35 years ago.
    Yes a 67 B250 318 3spd, completely restored. Sold years ago when kids arrived, Death Trap and lacking rear seats and belts. Your aging yourself! Im from the same vintage.

  19. #16
    Join Date
    Apr 2009
    Location
    Beaver County Alb. Canada
    Posts
    1,876
    Post Thanks / Like
    Likes (Given)
    542
    Likes (Received)
    922

    Default

    Quote Originally Posted by ewlsey View Post
    I'll just hope that is a joke.


    Ditch the button insert. Too much tool pressure. Get a regular 90 degree insert like a CNMG. You can get them in PCD.

    You need to check that the inserts are both at the same height. It's a homebrew cutter, so you probably need some adjustment.

    Try something like WD40 if you don't have coolant. Around 1500 RPM. PCD can handle the SFM.

    What kind of feed do you have? You need a consistent feed rate.
    Never found anything better than HSS on Manual machines for Alum. About the Crisco - probably work fine but I found Varsol works bout the best for Alum Finish cut and tapping.
    I agree ditch the Button Insert, CNMP works better than CNMG IMHO.

  20. #17
    Join Date
    Apr 2009
    Location
    Beaver County Alb. Canada
    Posts
    1,876
    Post Thanks / Like
    Likes (Given)
    542
    Likes (Received)
    922

    Default

    Quote Originally Posted by SVE Performance View Post
    What surface finish does the manufacturer call out ? Most will call out a particular finish to work with the head gasket .So unless you know what you need you don't know if it is good or not .Bill
    Absolutely- Find out what finish is required from the Manuf. To good and gasket will probably "Squirt Out" To coarse and the gasket will not deform enough to fill the voids.

  21. #18
    Join Date
    Mar 2002
    Location
    Brisbane, CA, USA
    Posts
    1,670
    Post Thanks / Like
    Likes (Given)
    73
    Likes (Received)
    195

    Default

    I fabbed up a very similar fly cutting tool for large aluminum parts, not cylinder heads but about the same size.

    I also tried a round insert first but didn't get very good results.

    What worked best was using an APTK insert that was designed for aluminum and is very sharp and polished, I got them from exkenna at www dot latheinserts dot com . They cut finishes in aluminum pretty much as well as sharp HSS tooling.

    Also I set the fly cutter up with an insert on each end, but set with one to "rough" and one to "finish". The roughing one was on a slightly larger radius, 0.005" or so. It would cut first then the "finish" insert at a slightly smaller radius would make the cleanup pass.

    After tweaking this in the finish came out really well.

    One other issue, it appears from the machining marks in the pictures that you have your flycutter pretty much centered on the cylinder head.

    You will get a better finish if you offset the flycutter so that it initially contacts the cylinder head edge as close to 90 degrees as you can get. Basically you want to initiate the cut with as large a chip as you can, rather than having it initiate the cut at a smaller angle to the edge which makes the initial chip much thinner. The ratio of your flycutter width to cylinder head width will limit how much you can change this but offset it as much as you can, this is something else you can tweak in.

    Paul T.
    Valve and Chassis Spring Tester Home Page - Power Technology Valve and Chassis Spring Tools

  22. Likes wheelieking71, Pete F, motion guru liked this post
  23. #19
    Join Date
    Dec 2007
    Location
    Southeastern US
    Posts
    6,401
    Post Thanks / Like
    Likes (Given)
    845
    Likes (Received)
    2808

    Default

    Not enough machine, too few inserts in the cutter is the cause IMHO. You are initiating deflection when one insert is loaded in the cut, deflection goes away when insert leaves cut and cutter/spindle combo "rebounds" about the time the second insert hits the head. For that job, either 1 insert or preferably - several so that you have at least 2-3 in the cut at all times to keep things loaded up.

  24. Likes Limy Sami, Garwood, sticks, motion guru liked this post
  25. #20
    Join Date
    Jan 2013
    Location
    Gilbert, AZ
    Posts
    6,190
    Post Thanks / Like
    Likes (Given)
    7872
    Likes (Received)
    7960

    Default

    I like PaulT's input. And everybody else is right. Sharp insert is key here. I also get the feeling you are a little confused as far as what "sharp insert" means. your cutting edge on that button insert may be sharp, but that is not a sharp insert. you want an insert that comes to a point. With as small a radius as possible. you have this: O you want this: V

    I also suspect the fixture. Lets see the set-up.


Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •