side housing lapping table
02-08-2007, 03:20 PM
#11
Senior Member
Join Date: Mar 2004
Location: MD
Posts: 558
1500 bucks? are u sure? that seems a good price!
everyone i've talked to recommends Lapping. Include Dave at mazdatrix and jim Tanner at Racing Beat.and the guys at rotorsports racing. In fact Jim Tanner actually told me i shouldnt rebuild the engine without lapping it.
Now obviously if you pay xtra for nitride coating it would be better but... as the poster above stated in regards to wear by the time your rebuilding the nitride coating is already gone so remving it isn't an issue cuz its not their anymore.
i had mine lapped and ported at racing beat.
-of course you can only lap them once at most then their not enought to lap again.
everyone i've talked to recommends Lapping. Include Dave at mazdatrix and jim Tanner at Racing Beat.and the guys at rotorsports racing. In fact Jim Tanner actually told me i shouldnt rebuild the engine without lapping it.
Now obviously if you pay xtra for nitride coating it would be better but... as the poster above stated in regards to wear by the time your rebuilding the nitride coating is already gone so remving it isn't an issue cuz its not their anymore.
i had mine lapped and ported at racing beat.
-of course you can only lap them once at most then their not enought to lap again.
02-08-2007, 08:46 PM
#15
Super Moderator
Join Date: Jul 2002
Location: My BIG ol TURBO-DIESEL
Posts: 5,181
Originally Posted by jwteknix' post='858099' date='Feb 8 2007, 05:07 PM
he is correct its almost like cutting a brake rotor but on the housing
Not quite.
A Brake Rotor is "cut"/machined on a lathe and a metal/ceramic bit is used to actually produce a new metal surfacw
My Definition:Lapping is the fininshing of an existing surface prodcued by rotating the part against a true fished lapping table while applying a slurry of lapping compound with a known grit value. In a pinch, housings have been lapped against each other with a slurry.
From a professional lapping shops definition: (ref. http://www.lapping.com/what_is_lapping.htm )
What is Lapping?
Flat Lapping is an ancient machining technique. The caveman who sharpened a stick by rubbing it against a stone covered with sand was the first to discover lapping. These days, we are a bit more sophisticated.
Lapping is a precision process or combination of processes used to provide flatness, parallelism, size and surface finishes to extremely demanding tolerances. The process is a manufacturing method that employs particles of an abrasive material to remove stock from a surface. It is comparable to sanding or grinding, except that sanding and grinding use abrasives which are fixed (bonded abrasives) whereas lapping employs abrasives which are suspended in a liquid carrier, and are free to move about.
Lapping and fine grinding are processes used where the surface finish, flatness, or parallelism of the work piece must be held to very close tolerances. Lapping can achieve a flatness rating of one millionth of an inch (0.000001"), parallelism tolerances of ten millionths of an inch (.00001") and surface finishes to 0.6Ra. using special handling and tooling techniques.
Abrading Methods can achieve flatness tolerances of 12 millionths (0.000012"), parallelism of fifty millionths (0.00005") and flatness of 1Ra on a volume production basis. We can achieve tolerances at the limits of the lapping process (down to one millionth of an inch) on a case-by-case basis.
Abrading Methods can provide lapping, free abrasive machining, flat honing, fine grinding, polishing, burnishing, precision fine grinding as well as special deburring and cleaning techniques to process your flat surfaces. With over 30 years of experience, special equipment and proprietary processes, Abrading Methods can produce flat and parallel surfaces from thousandths to millionths of an inch, in production quantities, at an economical cost.
Lapping is very specialized. I have/do utilize a specialty lapping shop that does nothing but lapping.
Some of there rotary clients include: Rotorsports Racing; Bruce Turrentine and an aftermarket apex seal manufacturer.
For the volume of lapping that a small shop would do, I hink you would better serve your customers by concentrating on providing a quality job/product than trying to do all things in-house. Just my opinion
02-09-2007, 08:07 PM
#19
Senior Member
Join Date: Oct 2001
Location: Peoria, AZ
Posts: 10,906
Originally Posted by Fd3BOOST' post='857845' date='Feb 7 2007, 02:24 PM
Well I wouldn't know how much the machine itself is worth. I'm curious why you are interested in one? After looking into have a set of irons lapped for myself. It became obvious that the lapping alone is pointless unless you are able to have the irons nitride coated and heat treaded to boot. Otherwise the irons will wear a lot faster than normal. Why your interest?
Thats true if you're looking to last 100k miles.
Race orientated stuff its worth doing for the extra power...
02-09-2007, 08:59 PM
#20
Senior Member
Join Date: Jun 2002
Location: La Plata, Maryland
Posts: 9,725
Originally Posted by 1Revvin7' post='858357' date='Feb 9 2007, 06:07 PM
Thats true if you're looking to last 100k miles.
Race orientated stuff its worth doing for the extra power...
When I was looking into this last summer. What I found on the web led me to believe that a lapped plate would wear down dramatically faster than a nitride coated plate. Engine life expectancy around 40-50k before she would start smoking like a chimney. I could see lapping irons if i was racing and rebuilt engines often. It doesn't make much sense for a street car. The cost for decent used irons was way less than the cost to properly lap and re-nitride coat and pay for shipping both ways.