# Difference between a jig and a fixture



## dan_house (Feb 18, 2009)

I think I know....

a jig is simply a guide, one pice maybe, possibly disposable after its intended use.

A fixture is a device that can be adjusted in ways, and it is intended for repeated use.

Or am I really off base?


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## Ghidrah (Oct 21, 2008)

I call it a jig whether it's adjustable or not.


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## bobj3 (Jan 17, 2006)

Hi Dan

This just my 2 cents 

A jig is a device that can be use for one type of job the norm but can be used to make more than one copy of the item.

A fixture is almost the same but it can be used to do many jobs and can be adjusted to do the other jobs like the item below..
http://us.oak-park.com/catalogue.html?list=RTS-MGS-

Many say they want a sled for the router table, the OP fixture above is one of the best because it can do so many jobs..(fixture)


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dan_house said:


> I think I know....
> 
> a jig is simply a guide, one pice maybe, possibly disposable after its intended use.
> 
> ...


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## Ralph Barker (Dec 15, 2008)

I've read discussions on this issue/question elsewhere. The conclusions always seemed rather fuzzy to me. To some, portability (what gets clamped to what) seems to be one measure of the difference. To others, the criteria seems to be what moves, the cutting machine or the work piece. 

I gave up and simply call all the helper-thingies I make jigs.


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## dovetail_65 (Jan 22, 2008)

Ralph Barker said:


> I've read discussions on this issue/question elsewhere. The conclusions always seemed rather fuzzy to me. To some, portability (what gets clamped to what) seems to be one measure of the difference. To others, the criteria seems to be what moves, the cutting machine or the work piece.
> 
> I gave up and simply call all the helper-thingies I make jigs.


Both hold the workpiece. But *a jig guides the cutting tool *whereas a fixture does not guide the cutting tool,* a fixture guides the workpiece*.

Above is the simplest explanation I can think of. They are used interchangeably these days.


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## dutchman 46 (May 23, 2007)

*Jig or fixture???*

 If memory serves me rite, a jig is used to guide a tool(router), and does not necessarily attach to the router or table, but may hold the stock. A fixture may guide the work, and is attached to the table. :'(
Does that make any since?? :'(


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## bobj3 (Jan 17, 2006)

HI Howard

Yes it makes "since "

One note. a brass guide in the router or the router table is a fixture. 
That can be switch out to make a new type of cut..or offset...
=



dutchman 46 said:


> If memory serves me rite, a jig is used to guide a tool(router), and does not necessarily attach to the router or table, but may hold the stock. A fixture may guide the work, and is attached to the table. :'(
> Does that make any since?? :'(


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## levon (Sep 14, 2008)

not one post here makes any clarity or sense. a jig is an irish dance. a fixutre is either a light or a commode. my definition is a joke, but most of the definitions given here are also jokes. imho.why worry about words or definitions, just say its something i built to do the job? too simple?


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## levon (Sep 14, 2008)

nickao65 said:


> Both hold the workpiece. But *a jig guides the cutting tool *whereas a fixture does not guide the cutting tool,* a fixture guides the workpiece*.
> 
> Above is the simplest explanation I can think of. They are used interchangeably these days.


Nick, if a fixure doesnt guide the cutting tool, then a dovetail fixture as called by the companies that sell them are actually dovetail jigs. they guide the cutting tool. im not making an example of you , several on this thread said the same thing. im just not sure any of it makes cents,


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## dovetail_65 (Jan 22, 2008)

The Katie jig is actually a fixture, The Katie attaches to the part and the tool(router table) stays stationary. You move the fixture and part around.

A Leigh D-4 dove tail is a jig because it stays stationary and you actually move the tool(the router) around. The part and jig stay still.

But even the Katie "jig" is marketed as a jig so I still think everyone just interchanges them now.

Remember it like this:

A jig guides, A fixture slides.


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## levon (Sep 14, 2008)

Nick, thats waht im saying its all confusing, did you get pm?


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## dovetail_65 (Jan 22, 2008)

Yeah not a problem at all.


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## levon (Sep 14, 2008)

Thanks Nick!


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## allthunbs (Jun 22, 2008)

nickao65 said:


> The Katie jig is actually a fixture, The Katie attaches to the part and the tool(router table) stays stationary. You move the fixture and part around.
> 
> A Leigh D-4 dove tail is a jig because it stays stationary and you actually move the tool(the router) around. The part and jig stay still.
> 
> ...


A fixture attaches to the workpiece and guides the workpiece into the bit (router typically mounted in a table etc.) A jig holds the workpiece and guides the bit into the workpiece? (workpiece clamped to bench)

A jig guides, A fixture slides. 

If we are all in agreement I'll put it in my notes.

Allthunbs


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## levon (Sep 14, 2008)

no disrespect, allthumbs , i see no proof of what you are saying. tell me where this is spelled out. as i see it, this is your opinion and as we all know opinions are like other things, everyone has one.


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## allthunbs (Jun 22, 2008)

levon said:


> no disrespect, allthumbs , i see no proof of what you are saying. tell me where this is spelled out. as i see it, this is your opinion and as we all know opinions are like other things, everyone has one.


Oops, I'm asking for concensus not expressing an opinion. The membership has presented a reasonable explanation and I'm just asking for corroboration.

Allthunbs


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## levon (Sep 14, 2008)

i am seeing differing points of view. i think it is futile to think there is a concensus. i am totally prepared to say i am wrong. but dont see that from people that voice other opinions. also you said bobj flamed you. i know bobj is not going to post here to disagree, he is just too big a person. i read the posts and didnt see where he flamed you. in fact, i agree that some posts can be too long. this is just a feeling of mine. not a critique. i think its time for someone to speak up for someone who has helped a lot of people!


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## Ghidrah (Oct 21, 2008)

So what would you call the white thing, a jig or fixture?








It restricts the position of material and will accommodate any width material up to 11 7/8" wide. It is also affixed to the bed of a molder.


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## bobj3 (Jan 17, 2006)

Hi Ron

I would call it a jig ladder   for the molder,,,



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Ghidrah said:


> So what would you call the white thing, a jig or fixture?
> 
> It restricts the position of material and will accommodate any width material up to 11 7/8" wide. It is also affixed to the bed of a molder.


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## allthunbs (Jun 22, 2008)

Ghidrah said:


> So what would you call the white thing, a jig or fixture?
> It restricts the position of material and will accommodate any width material up to 11 7/8" wide. It is also affixed to the bed of a molder.


That's not playing fair. It's hard enough to keep things reasonably straight with routers and you go and add a molder. If the "white thing" were being used with a router, it would be a jig. If it were being used with a molder, it must be a fixture but then do molder's have as many options and different methods of use that a router has? Can a molder be used freehand? I used to have a molding head for my radial arm saw. Scared the h_ll out of me every time I used it. I used to think the blades were going to fly off. I sure couldn't imagine using that freehand.

Ok, Ron, I bite, what is it and how does one use it? ;-) Well done! You've got me thinking now.

Allthunbs


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## dovetail_65 (Jan 22, 2008)

Ghidrah said:


> So what would you call the white thing, a jig or fixture?
> 
> 
> 
> ...


Some jigs/fixtures are both jigs and/or fixtures depending on how you use them at any given time.

All I did was look in about 20 woodworking books I have here and they all say the same thing.

I say it is a jig because it does not move across a cutter with the material. If you think about it , it does actually guide or direct where the cutter will cut, still making it a jig. If the "white thing" went through the planer with the wood I would call it a fixture. Many beds similar to this do go through the planer. 

Actually isn't that just a "bed".

These fine line things are just another reason why the terms are used interchangeably which is fine to me.


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## Ralph Barker (Dec 15, 2008)

nickao65 said:


> Both hold the workpiece. But *a jig guides the cutting tool *whereas a fixture does not guide the cutting tool,* a fixture guides the workpiece*.
> 
> Above is the simplest explanation I can think of. They are used interchangeably these days.


So, a radial arm saw is actually a jig, and a table saw is a fixture.


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## dan_house (Feb 18, 2009)

geeezzzz almost sorry I asked.... 

I'm going with the jig guides, the fixture moves.

I have made 2 jigs then. Will post when I get home for pics.....


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## allthunbs (Jun 22, 2008)

nickao65 said:


> Some jigs/fixtures are both jigs and/or fixtures depending on how you use them at any given time.
> 
> All I did was look in about 20 woodworking books I have here and they all say the same thing.
> 
> ...


I was under the impression that a planer "bed" could adjust to present a "best case" to the planer knife. This example doesn't appear to do so.



nickao65 said:


> These fine line things are just another reason why the terms are used interchangeably which is fine to me.


Which is a pain in the butt for me. I'm trying to get all of this stuff organized in my head. By applying multiple definitions, only serves to confuse the issue, especially when there remains so many functions that remain unnamed.

I once had a difference of opinion with a judge over the use of the words "judgement" and "judgment." He was adament that "judgement" was the term to be used by judges when passing "judgement." I looked through texts and documents going back several hundred years and discovered that there indeed is a difference: "judgment" is defined as that expressed by a judge pursuant to an act or law enacted by a governing authority. "Judgement" is that intelligence used by scentient beings to determine "their best path of action."

Thus multiple definitions only serves to confuse. I still ask that you determine the following:

"A fixture attaches to the workpiece and guides the workpiece into the bit (router typically mounted in a table etc.) A jig holds the workpiece and guides the bit into the workpiece? (workpiece clamped to bench)

A jig guides, A fixture slides.?"

Yay or nay?


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## harrysin (Jan 15, 2007)

OK guys, this is what one of my engineering books says about fixtures:

When special work-holding devices are required, they are generally made in the shop to suit the specific job. These devices are usually attached to the machine table and are called FIXTURES. end of quote.

Mr. R.J. DeCristoforo in one of his books on designing jigs says:
The new jig might enable the tool to do something the designer never envisioned, or it might increase accuracy with minimum fuss, or it could add a safety factor to a routine operation. In any case it has to be custom made since it is rarely available commercially.

As far as I'm concerned, a jig is anything that holds the material to enable a specific operation to be carried out.


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## dovetail_65 (Jan 22, 2008)

"A fixture attaches to the workpiece and guides the workpiece into the bit (router typically mounted in a table etc.) A jig holds the workpiece and guides the bit into the workpiece? (workpiece clamped to bench)

A jig guides, A fixture slides.?"

Yay or nay?



The above is YAY with some clarifications.

All fixtures do not attach to the work piece though they do all GUIDE the workpiece. A table saw fence is a fixture, it guides the workpiece into the blade even though it does not slide. It's like English there are exceptions to every rule. "guides the workpiece" is the point.

In their simplest terms:

*A jig guides the cutter.

A fixture guides the workpiece.*

So I guess a bed is a Fixture or jig depending on the tool you are using to cut. You can make a bed and use a router to plane a piece of lumber with that bed, in that case the "bed" is a jig. When using a bed on a planer it is a fixture. I think I may have stated that incorrectly in a previous post.

Harry, the R.J. DeCristoforo book are good, I have several. If you have more than just one you will find he does differentiate the definitions for fixture and jig, it may be the book his son helped publish after his death. I will have to go through my library to find which book exactly he describes and defines each.

Okay it is in the book; *R.J. De Cristoforo's Best Jigs, Fixtures & Shop Acces* where he defines each.


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## bobj3 (Jan 17, 2006)

Hi Nick

Talking about guides, I'm still in a hold pattern waiting for the snapshots of your brass guides  and your two router tables and your work bench with the holes in it for the dogs..  I know you are trying to make a buck and keep the kids in line but PLEASE take the time to get me off your back about the pictures.. 

Once it gets locked in my head it just go's around and around... 

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nickao65 said:


> "A fixture attaches to the workpiece and guides the workpiece into the bit (router typically mounted in a table etc.) A jig holds the workpiece and guides the bit into the workpiece? (workpiece clamped to bench)
> 
> A jig guides, A fixture slides.?"
> 
> ...


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## allthunbs (Jun 22, 2008)

Mr. DeCristoforo is the author but each and everyone of you are the experts. I will defer to your greater experience. That said, I have to assume that you all agree with Mr. DeCristoforo, to wit:

*A jig guides the cutter.

A fixture guides the workpiece.*

My notes now reflect the difference between templates, jigs and fixtures and I'll start to explore those elements that are most important for router usage.

Thank you all for your considered opinion and input.

Allthunbs


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## gkalrido (Dec 12, 2008)

Hi, 

I,m a newbie, and thought I'd add my 2 cents worth.

According to Wikipedia - 
The terms "jig" and "fixture" are often confused. A jig locates on the work and guides a tool. 
A fixture holds the work in a fixed location. 
A device that does both functions (holding the work and guiding a tool) is called a jig. 
A device that only holds work and does not guide a tool is properly called a fixture, not a jig. 
The CNC era has reduced the need for jigs, whereas fixtures are still commonly used.

Another reference is Jig and Fixture Design by Franklin D Jones, Chap.1-
As a general rule, however, a jig is a special tool, which, while it holds the work, or is held onto the work, also contains guides for the respective tool to be used; whereas a fixture is only holding the work while the cutting tools are performing the operation on the piece, without containing any special arrangements for guiding these tools. 
The fixture, therefore, must, itself, be securely held or fixed to the machine on which the operation is performed; hence the name.
A fixture, however, may sometimes be provided with a number of gages and stops, although it does not contain any special devices for the guiding of the tool.

Hope this helps.

gkaleido


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## allthunbs (Jun 22, 2008)

gkaleido said:


> I,m a newbie, and thought I'd add my 2 cents worth.
> 
> According to Wikipedia -
> The terms "jig" and "fixture" are often confused. A jig locates on the work and guides a tool.
> ...


I got a good chuckle out of this. Excellent research George. Here we'd thought we had resolved the issue and along comes a fresh face with a new take on the problem. Ok, back to the drawing board. Do we accept George's arguments, do we beat them to death, or do we scrutinize them like we did all the others?

Allthunbs


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## Ralph Barker (Dec 15, 2008)

allthunbs said:


> I got a good chuckle out of this. Excellent research . . . Do we accept George's arguments, do we beat them to death, or do we scrutinize them like we did all the others?


I vote we cut him some slack, considering he's a newbie and all. 

"The CNC era has reduced the need for jigs, whereas fixtures are still commonly used." is the only part I'd quibble with, since I don't know anyone with a CNC router system.


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## harrysin (Jan 15, 2007)

Well everyone,I think it's a case of semantics, for my part these shots show what I call things but it really doesn't matter so long as we all understand each other, and I'm sure we do.


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## bobj3 (Jan 17, 2006)

Hi Harry

I have a question for you that I have wanted to ask for a long time..

I see the template but my question is how did you make the template,scroll saw,glue up parts,jig saw,free hand router,ski jig, ??? , I know you like to use the glue up way but the one you posted is all one piece as far as I can tell ...

Same question for a male template to go with the female template ?

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harrysin said:


> Well everyone,I think it's a case of semantics, for my part these shots show what I call things but it really doesn't matter so long as we all understand each other, and I'm sure we do.


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## curiousgeorge (Nov 6, 2006)

I have a question... Does it really matter if it is a jig or a fixture as long as it does what it was built to do? For example; I have some jigs? that have become fixtures in my shop.


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## Ralph Barker (Dec 15, 2008)

The most important question, of course, is what is being poured into the jig-ger.


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## bobj3 (Jan 17, 2006)

Hi George

I will agree with you on this one,,,it just like a light fixture ,it just helps you get the job done 

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curiousgeorge said:


> I have a question... Does it really matter if it is a jig or a fixture as long as it does what it was built to do? For example; I have some jigs? that have become fixtures in my shop.


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## harrysin (Jan 15, 2007)

bobj3 said:


> Hi Harry
> 
> I have a question for you that I have wanted to ask for a long time..
> 
> ...


Bj, I'm glad you asked the question because the template posted was a bad example, made a long time ago before I was taught an easier way. This new photograph of a later version shows with black lines the individual pieces glued together. A template guide passing over the square corner will still produce a perfect radius. The second shot shows my very first male template for routing the same pattern, I must have made that about 25 years ago.


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