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Profile and position callout

Profile and position callout

Profile and position callout

(OP)
I have a simple rectangular part, 6"x4"x.125" thick with a hole in the center.

The flat surface is called out at "A".

The 6" edge is "B".

The 4" edge is "C".

Profile of the perimeter is called out to be .01 with respect to datum A.

The position of the hole is called out with respect to ABC.

Is this a valid GDT callout?

Specifically, is it acceptable to callout the perimeter with a profile, and then use the edges as datums to find the hole?

The perimeter is not being called with respect to ABC, so I think it is ok.

RE: Profile and position callout

Yes, it's OK.  The profile tolerance controls the form and orientation of the two sides.

Realize that the .01 tolerance is not carried over to the position tolerance.  (When the position is checked to ABC, those three datums are formed by high-point contact, even if B and C are wavy or slightly angled.)

John-Paul Belanger
Certified Sr. GD&T Professional
http://www.gdtseminars.com

RE: Profile and position callout

(OP)
Thanks for your reply John-Paul.  

I just wanted to make one thing clear.  The profile callout for the perimeter of the part is .01 all around.  The profile callout is not from one datum to another.  Is this still ok?

 I know that it is would not be "legal" to call out the profile .01 ABC all around.

Thanks again!

RE: Profile and position callout

Yes -- all is A-OK and the answer wouldn't change.      :)

John-Paul Belanger
Certified Sr. GD&T Professional
http://www.gdtseminars.com

RE: Profile and position callout

I'm not sure that it would be illegal to call out the profile to ABC all around.  This would force A to be flat within .005 and B to be perpendicular to A within .005.  

I'm not recommending this practice, but I don't think it violates any Y14.5 rules.  What do you think, John-Paul?

Evan Janeshewski

Axymetrix Quality Engineering Inc.
www.axymetrix.ca

RE: Profile and position callout

Hmmm -- illegal might be too strong of a word, but I don't think it would add any value.

The corners are already implied to be 90º so the perpendicularity of the four corners would automatically be controlled to .01 by virtue of the "all around." Referencing B and C in there would almost be circular logic since two of the edges are forming B and C.  And the flatness of datum feature A is not affected at all.

John-Paul Belanger
Certified Sr. GD&T Professional
http://www.gdtseminars.com

RE: Profile and position callout

axym,
I too am under the impression that it would cut the iolerance to the datums as you say, anyone else?

RE: Profile and position callout

Do you guys think that restraining the perimeter to ABC cuts the tolerance in half?  I don't think so -- I'll have to play around with a sketch and think...

How about this:  By referencing ABC, what additional quality would it control?  Size, location, orientation, or form?  Those four qualities were already tackled by having profile all around to datum A.  And the effective tolerance value wouldn't change because the datums that are created are from high-point contact anyway.

John-Paul Belanger
Certified Sr. GD&T Professional
http://www.gdtseminars.com

RE: Profile and position callout

The original concept with profile of a surface to datum A looks fine as long as the leader line indicates "ALL AROUND".

If one referenced the profile to secondary datums B and C in addition to the primary, would one check datum B and C or assume they are perfect? One could always say that rule #1 would control the form including datum B and C surfaces but I think we had this discussion before.

One would have to assume datums B & C were perfect thus we are not checking the full perimeter only two (2) other sides relative to A, side datum B & end surface datum C.

I think the original method is best.   

Dave D.
www.qmsi.ca

RE: Profile and position callout

Thanks Dave,
I agree -- and this saves me from making a sketch, which I always seem to goof up when it comes to posting one on the forum.

John-Paul Belanger
Certified Sr. GD&T Professional
http://www.gdtseminars.com

RE: Profile and position callout

I was not intending to recomend that option I was just trying to verify with others, the valididty of the reason I would not recommend it. I do believe it is forced to be correct. If you have a simple square part and one side or two are datums and a profile is used all around the opposite sides can only stay in their required tolerance band if the datum surface only veries inside of the true profile.

RE: Profile and position callout


The original post of profile callout with only one primary datum is absolute correct and I don't think we need secondary and tertiary datum on the all around profile callout, the reason is to avoid profile specifications that are confusing, Alex Krulikowski mentioned Profile Datum Rule in his book Advanced Concepts of GD&T Chapter 22  : A profile control should not be applied to the surfaces it references as datum features, he says it's a common sense rule since confusion will exists on how to interpret the profile tolerance zone in the datum contact areas with the features, please look at fig 22-10 for detailed information.

SeasonLee

RE: Profile and position callout

I still think that the tolerance for the datum features is effectively cut in half.  Dave, we wouldn't ignore datum features B and C or assume that they're perfect.  Rule #1 doesn't enter into it either.

When only datum feature A is referenced, we can translate and rotate the zone to try to get everything in.  When datum features B and C are referenced as well, the zone is the same but it must be oriented and located to the datums.  The datums are on the high points of the datum features, so the datum features can only use half of the zone.

This is hard to convey in words, so here's a diagram showing the two scenarios.  Again, I'm not recommending that this technique be used but here's what it would look like if it was used.

Evan Janeshewski

Axymetrix Quality Engineering Inc.
www.axymetrix.ca

RE: Profile and position callout

I agree with SeasonLee reflecting Alex Krulikowski's thought on profiles and Evan's diagram referencing profile of a surface all round to A, B and C just doesn't make sense. It is confusing.

Whenever we have a datum surface that does not have a geometric qualifier, we must assume that datum surface is perfect and as per section 4.10.1 (2009 edition) we use a 3 point contact on the primary, 2 points on the secondary and 1 point on the tertiary. This hasn't changed since I was measuring parts so many years ago. Of course, we could look for the high points on the surfaces but that only happens when checking fixtures are used and not on a CMM. Do you think a CMM Operator will scan a surface for the high point and then try to develop 2 other points to stabilize the part? Don't think so.

 
 

Dave D.
www.qmsi.ca

RE: Profile and position callout

I still disagree, Evan  :)

The profile tolerance zone is equal bilateral around the "true profile." You are making the datum planes the true profile, and that's not the case. The true profile is a perfect shape -- and here's the key -- at the prescribed distance from the datums as given by basic dimensions.

Are you saying that the basic distance from datums B and C to the true profile are zero?  But datums B and C are formed from the high points of the actual edges.  Thus we have a circular argument, and I say we should leave off B and C altogether.

John-Paul Belanger
Certified Sr. GD&T Professional
http://www.gdtseminars.com

RE: Profile and position callout

Dave,

I agree that referencing the profile all around to A, B, and C is confusing and I wouldn't recommend doing it.

But I'm not sure where you got the idea that we must assume the datum surface is perfect.  The datum feature simulator is nearly perfect, and the datum is perfect.  Here's what the standard says in 4.10.1:

"Where a surface is specified as a datum feature, the high point(s) establish a datum plane".

That's the principle.  When an imperfect datum feature interacts with a perfect simulator, the contact is at the high points.  All the other stuff about the number of points of contact is derived from this principle.

This isn't the same thing as picking 3 random points on the primary, 2 on the secondary, and 1 on the tertiary.  If the CMM operator does that and therefore doesn't find the high points, then it's not the same datum reference frame!  Maybe that's what you mean about assuming that the datum feature is perfect.  It would have to be perfect for the random 3-2-1 method to get the proper datum reference frame.  I would agree that most CMM operators would use the method that you described and not find the high points.  But that doesn't make it any less wrong.  I was a CMM programmer once myself, and learned the lesson of high point datums the hard way.

John-Paul,

Am I making the datum planes the true profile?  Yes, I think that makes sense.

Am I saying that the basic distances from datums B and C to the true profile are zero?  Yes, I'm fine with that as well.  Datums B and C are formed from the high points of the datum features.  I don't think it's a circular argument.

I've attached a closeup of the diagram, with the different pieces of geometry labeled.  The true profile (purple solid line) and the datum (dashed black line) are coincident.  Do you think this makes sense?

It's too bad that Y14.5 relies so heavily on the special case of three mutually perpendicular planar datum features as an example.  It masks some of the subtleties of datum reference frames because the true profiles, the datum planes, and the planes of the datum reference frame are all coincident.

Evan Janeshewski

Axymetrix Quality Engineering Inc.
www.axymetrix.ca

RE: Profile and position callout

Quote (axym):

I agree that referencing the profile all around to A, B, and C is confusing and I wouldn't recommend doing it.

   Using A and B as profile datums makes sense to me.  Datum_C, the tertiary datum, is defined by the perimeter, so it cannot control the perimeter.  B also is defined by the perimeter, but it provides control over the 4"_sides.

               JHG

RE: Profile and position callout

Evan:

You said ""Where a surface is specified as a datum feature, the high point(s) establish a datum plane".

Since you were a CMM programmer, please reveal to us how one would set up with a high point using a CMM without using a 3 point set up on a plane as described in 4.10.1? There is only 1 high point so take it from there. How would one set it up in real life?  

Dave D.
www.qmsi.ca

RE: Profile and position callout

Evan,
On your last sketch, how is it that the true profile just happens to also be the same as the high points? If the surface hovered near the upper limit of the zone, then the datum plane would move up there.  Would your true profile also move?

Also, would any of this discussion change if we were looking at a single flat surface (rather than four sides) and use profile of a surface to itself as a datum?  I think most people would see the problem with that.  So I'm trying to figure out what's different when there are four sides...

John-Paul Belanger
Certified Sr. GD&T Professional
http://www.gdtseminars.com

RE: Profile and position callout

I sense that we're touching on something fundamental here.

The true profile didn't just happen to be the same as the high points.  If the surface hovered near the upper limit of the zone, the datum plane would move, and the true profile would also move.  The datum plane follows the high points, and the true profile follows the datum, and the zone follows the true profile.

If we were looking at a single flat surface with a profile to itself, it would seem even more ridiculous and more people would have a problem with it.  But I don't think that the geometry of the datum feature, simulator, and datum would change at all.

To me, it's another technique that is technically not illegal but could be considered a bad practice.  It's kind of like saying "the allowable gap between the surface of my foot and the perfectly flat floor I'm standing on must be zero plus or minus 0.25 mm". profile smiley

Evan Janeshewski

Axymetrix Quality Engineering Inc.
www.axymetrix.ca

RE: Profile and position callout

OK -- if the true profile goes wherever the datum plane goes, then what's the point of referencing the datums?

We already knew the geometry of the part from the true profile, and the datums contribute nothing in terms of orientation or location.

John-Paul Belanger
Certified Sr. GD&T Professional
http://www.gdtseminars.com

RE: Profile and position callout

Dave,

The datum reference frame is defined in terms of perfectly flat planes that the part is put into contact with.  Physically, this can be accomplished using three perpendicular surface plates.  This is what you've seen in functional gages.  The DRF is in the plates, and they contact the part at 3 high points on the primary datum feature, 2 on the secondary, and 1 on the tertiary.

If a CMM method is used instead, things are more difficult.  For each datum feature, you need to somehow approximate the plane that the physical plate would make contact on.  The random 3-2-1 method doesn't work.  On the primary datum feature, you need to probe a lot of points and then use the Tangent Plane algorithm.  On the secondary datum feature, you need to probe a lot of points and then find the "orientation constrained tangent plane".  Same thing for the tertiary.  Some CMM software packages have a built-in algorithm for orientation constrained tangent planes, but a lot don't.  So you often need to use other tricks to create them.  This is difficult, and I can understand why a lot of CMM operators don't go to these lengths.  But the reality is that the simple 3-2-1 methods commonly used on CMM's don't establish the right DRF according to the Y14.5 definitions.  It's one of the biggest hidden pitfalls of using CMM's.  Y14.5 was written in terms of physical simulators and high point contact and tangent planes, and approximating those using CMM's is not easy.

John-Paul,

If you don't feel that the true profile should go wherever the datum plane goes, then where should the true profile go instead?  The point of referencing the datum features, as it always is, is to orient and locate the tolerances zones.  

I'm not sure what you mean by the statement "we already knew the geometry of the part from the true profile".  Can you clarify?

I don't agree that datums B and C contribute nothing in terms of orientation or location.  In my first diagram, it is clear that the tolerance zone sits differently on the part when B and C are referenced.  When only A is referenced, the zone floats.  When B and C are referenced, the zone is oriented and located to the high points of B and located to the high point of C.

Evan Janeshewski

Axymetrix Quality Engineering Inc.
www.axymetrix.ca

RE: Profile and position callout

Evan:

I do not disagree with finding the high points using checking fixtures but on a CMM, it is not done and that is reality.

Even if one was lucking thinking they found the high point, how does one create the plane since you need at 3 points on a rigid surface.  I do realize the one could take numerous points using a CMM and create a best fit plane but does that include the high point or create a plane from the average of all the readings? It is the average of all the reading. How does one know that they have actually found the high point using a CMM?

Please explain the "tricks" that you mentioned in your last post which should be used by CMM Operators to find the high point and what should they do with it?

Per 4.10.1 it says "This primary datum feature contacts the datum feature simulator on a minimum of three points." This method is used if the feature if it is "rocking or unstable". I think finding a high point would render the feature unstable and susceptible to rocking.



   

Dave D.
www.qmsi.ca

RE: Profile and position callout

Dave,

We're starting to get way off topic here.  CMM verification of GD&T is a whole other ball of wax.  Perhaps we should start a separate thread.

I will comment on your reference from 4.10.1 though.  It sounds like you're bringing some unrelated datum target concepts in and applying them to full-surface datum features.  When it says "this primary datum feature contacts the datum feature simulator on a minimum of three points", it's not referring to the number of points you need to pick on the datum feature to define a plane.  It means that when the primary datum feature (an imperfect surface) and its datum feature simulator (a perfect plane) are brought together to constrain 3 degrees of freedom, then the contact will be at 3 points.  When the secondary datum feature (an imperfect surface) and its datum feature simulator (a perfect plane that is exactly perpendicular to the primary simulator) are brought into contact to constrain 2 DOF's, the contact will be at 2 points.  Similar logic applies for the 1-point contact on the tertiary.

The reference to rocking or unstable datum features is to address possible convex conditions in which 3-point contact could be made in more than one way.  One way to prevent rocking and instability is to specify datum target points.  But that is a different thing entirely.  With datum targets, the locations of the simulators (and thus the contact points) are well defined relative to each other.  With full planar simulators, the contact is on the high points and will be different on every part.

Evan Janeshewski

Axymetrix Quality Engineering Inc.
www.axymetrix.ca

RE: Profile and position callout

Hi again Evan,
Per my last post, I meant that since the tolerance zone is all around, it follows the true profile.  We know the true profile because the basic dimensions for length/width would be given.  And the "implied 90" rule tells us that the four corners are perpendicular (basic angle).

Now superimpose the tolerance zone -- equal bilateral -- over that true profile.  The size and form are controlled by this tolerance zone.  But so are location and orientation. Location meaning the "position" of each edge from the opposite edge; and orientation because the perpendicularity of the four corners is constrained within our tolerance zone.

Referencing datums B and C adds no value to what I've described above. I sorta see what you mean about getting half the tolerance zone, but I'm just saying that we shouldn't go down that road in the first place.

John-Paul Belanger
Certified Sr. GD&T Professional
http://www.gdtseminars.com

RE: Profile and position callout

John-Paul,

The tolerance zone straddles the true profile, which is defined by basic dimensions and implied basic 90's and parallel relationships.  No argument there.

The all-around profile tolerance zone controls the overall form and size of the pattern of surfaces (as long as we're clear that we're using the term "size" in the generic sense and not bringing in the Y14.5 idea of size).  Orientation and location are controlled, but only in a relative sense.

Referencing datums B and C may not add any "value", but it does have an effect.  For example, the perpendicularity of the left and right sides of the part relative to datum feature B is controlled more tightly.

I agree with you that we (as designers) shouldn't go down that road in the first place.  But sometimes we (as QA) have to go down that road because the designer did.  I have seen this exact thing on prints before.  The designer had specified a general profile tolerance to ABC, that covered all of the surfaces on the part.  The datum features were included in the profile tolerance, so the self-referencing effect was there.  So we had to figure out whether or not this was legal and, if it was, how to orient and locate the tolerance zone to inspect the part.

Evan Janeshewski

Axymetrix Quality Engineering Inc.
www.axymetrix.ca

RE: Profile and position callout

OK, I really like this one, and I have a tangent to go to in a moment.

Evan, all-around is not the same as all-over, so the flatness of datum feature A and the opposite face are not controlled by the all-around surface profile.  I do, however, agree with you that the tolerance zones for datum featues B and C are effectively cut in half when referenced in the all-around datum reference frame.  And also agree that the shop is unlikely to ever recognize that reality. I would definitely just reference datum A in the all-around profile control. Tks for posting the graphic.

Dave, we've talked on the CMM simulation of datums before, and I still say that datum simulator fixturing should be used on CMMs.  You have experience in certain sectors, and I have it in others.  In (too few) cases, datum simulator fixturing is indeed used; it speeds setup and improves repeatability.  No, it isn't practical in all situations, but I've established that it is often cost effective even on very large items such as 20'x5'x8' welded frameworks.

Now, my tangent scenario.  Picture two coaxial cylindrical features used to establish a common datum axis, with a total runout control applied to each individual datum feature surface and referencing back to the common datum axis.  This concept tends to blow the minds of designers and inspectors because they forget that datums and datum features are not the same thing.  Granted it's unpleasant to inspect because you have challenging fixturing, but it is often the functional requirement, such as when bearing surfaces on a shaft are used as datum features.  Just something for y'all to munch on.


 

Jim Sykes, P.Eng, GDTP-S
Profile Services  www.profileservices.ca
TecEase, Inc.  www.tec-ease.com

RE: Profile and position callout

Jim,

Regarding your tangent scenario, you're talking about something like features C and D in Fig. 6-51 in '94 or Fig. 9-6 in '09.  I've munched on this before, and it always leaves a bad taste.

Referencing the total runout controls for C and D back to C-D is a pain, and I don't think it's functional anyway.  I would prefer a single total runout control that applied to both C and D and didn't reference any datum features.  If you can find an axis that both C and D have total runout of .02 relative to, then the part passes the tolerance.  But this isn't currently allowed in Y14.5.  So we're stuck with the "self-inflicted" runout.

The thing I have a problem with is referencing a pattern of features of size as a datum feature RFS.  The exact behavior of the datum feature simulators, and thus the definition of the "common datum axis", goes into the twilight zone.

Evan Janeshewski

Axymetrix Quality Engineering Inc.
www.axymetrix.ca

RE: Profile and position callout

Evan, I don't get the bad taste, but it's a buggar to fixture.  You are controlling the location of each surface to the common axis; not sure how that's not functional.  Following your preference, you'd do a total runout on the two surfaces to find a common axis to which both the individual features would be controlled, then what?... you'd control all the other features back to that common axis?  What I read in your preferred scenario is essentially what referencing back to C-D accomplishes in the first place, or am I missing something not communicated yet?

I don't have a problem with patterns at RFS; I've worked with a few precision situations where it was absolutely necessary, and so a corporate addendum to the '94 standard was issued.

Jim Sykes, P.Eng, GDTP-S
Profile Services  www.profileservices.ca
TecEase, Inc.  www.tec-ease.com

RE: Profile and position callout

I too wonder about a datum being a pattern of holes at RFS.  Perhaps I'm thinking of it too much from a hard-fixturing point of view, but what happens if one of those holes is out of position slightly?

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems

RE: Profile and position callout

Jim,

Controlling the location of each surface to a common axis is functional, I don't have a problem with that.  The aspect that leaves the bad taste is inspecting the total runout on features C and D.  If we were to set up datum axis C-D using physical equipment, features C and D would be inserted into two precisely coaxial chucks.  But once C and D are covered up by the chucks, how do we inspect the total runout on them?  The inspection could be done using a CMM, but Y14.5 wasn't written with CMM's in mind so I wonder what the real intent was.  That's why I think that having the tolerances on C and D referencing the common axis C and D is a pain and probably not functional.

It would be better to have a separate tolerance on the datum features, to qualify them for use as datum features.  This limits the uncertainty in the common datum axis that will be extracted from them.

I have some further comments (questions really) on exactly how the two chucks would be adjusted to establish the C-D axis (the problem of the pattern-of-cylinders datum feature at RFS).  As John-Paul brought up, ambiguities can arise if C and D are not perfectly coaxial (which they never are).

Perhaps in the next post.

Evan Janeshewski

Axymetrix Quality Engineering Inc.
www.axymetrix.ca

RE: Profile and position callout

Gosh -- When I posted my last comment I wasn't really paying attention.  You guys are talking about two coaxial cylinders, a la Fig. 4-25 of Y14.5.  I don't know if that's such a big deal; the holding device simply closes down until it gets a good grip on the two cylinders.

My comment was targeted at Jim's statement that there's no problem with patterns at RFS.  I was thinking of something like Fig. 4-26, if it didn't have MMB on datum reference B.  Then I think we'd be in a tight spot.
 

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems

RE: Profile and position callout

axym,
I am sorry to have to disagree; I see 2 bearing journals establishing a common (spindle) axis as a VERY functional thing. I believe you are using the term functional, when you seem to mean "easy to inspect". This is one of the things I have been trying to get a feel for from this group, and appear to be slightly be more radical on, so to speak.  In my opinion design criteria requirements is what we want to inspect for, easy or not, what else is the point.
In my machine tool days, I have seen these spindles inspected on a machine with a micro-tilt table with adjustable indicators. They place a spindle, large end down on the table and have an indicator on each bearing journal. The table is tilted until the indicators are zeroed for a full rotation. Another indicator is on a movable slide to traverse the toleranced features. I did not do this myself, it is obviously a special dedicated machine and not necessarily easy.
I need to start another topic on this runout thing. I am not sure runout is a functional thing, I see it as as an easy to inspect thing?
 

RE: Profile and position callout

Haven't seen it myself, but an inspector described a fixture he used to hold the bearing-surfaces C & D to establish the primary datum axis, then clamped up on other coaxial features, released the C & D clamps, and went on to check the C & D surfaces.  Complicated, yes, but apparently doable.  

My preference with the coaxial bearing surfaces is to specify the tooling centeres in the ends of the part as the datum features (C-D); it has little effect on the inspected outcome or the function, and is typically how ALL those features were produced in the first place, so little effect overall.  Even when the part comes back for refurbishment, those tooling centres are typically in good enough shape to re-establish the datum axis again.

Jim Sykes, P.Eng, GDTP-S
Profile Services  www.profileservices.ca
TecEase, Inc.  www.tec-ease.com

RE: Profile and position callout

Jim,
I, in no way, meant to imply it is the only way possible. Can't you inspect to centers and take the relative measurements and get close to there anyway for a simpler solution than special equipment? I really am a book engineer and not a hands-on engineer. This is why I was looking for a forum to discuss issues like this. The point really is, it is absolutlely a possible functional requirement.

RE: Profile and position callout

No, no.  I understood it to be one possible method, just as mine was another.  I would be interested in seeing the setup you describe; I'm just not envisioning it right now, so I'm not sure how it establishes the datum axis or revolves around it.  Really, it's all going to come down to the tolerance, and how much risk you can tolerate.  I was dealing with surface profiles of 0.0025mm, and I don't know how much of that tolerance your suggestion would have eaten up; 10% is generally considered the accepted limit of measurement system error.  The results would not be the same, but may be acceptable depending on the tolerancing and function.  If you can accept more risk by way of possibly passing an unacceptable park, you may lower your production/inspection costs; on the otherhand, if a field failure of the component could mean signficant safety and/or cost issues, then you will be more risk averse and to a true rather than approximated inspection.  If you have some pics of the setup, that would be great.

Jim Sykes, P.Eng, GDTP-S
Profile Services  www.profileservices.ca
TecEase, Inc.  www.tec-ease.com

RE: Profile and position callout

Jim,
It has been 7 or 8 years since I worked there. I am thinking is was mimilar to the setup below, except, I seem to remember more indicators than one. I guess it is possible the zeroed indicators on the extremes of the bearing journals were just separate indicators, used only to zero out the table and as a control, that would work wouldn't it?
http://news.thomasnet.com/companystory/828297
I know this can not be the same one.
I believe using the relative indicators as a part is turning on lathe centers would lead us the same way would it not, except there is no adjustment it is either there or it is not?

RE: Profile and position callout

Hmm.  It seems more like a dynamic balance test to me, or like a manual means of trying to achieve what a CMM would do.  There seems to be a "differential" reading needed between the two journal indicators to establish a common axis of minimum total runout between the two surfaces.  I don't see that as exactly the same as using physical chucking, but may not be significantly different depending on the quality of the work (fabrication & inspection) and the tolerances specified.  After tilting the workpiece to establish/approximate a common axis, you'd then have to lock it down and start probing the other features.  

The double-chucking seems cumbersome for individual pieces, but on production runs, customized fixturing is often both cost-effective and practical.

 

Jim Sykes, P.Eng, GDTP-S
Profile Services  www.profileservices.ca
TecEase, Inc.  www.tec-ease.com

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