Mortising Jig

[Rocker]

Last year I published an article on this jig in the Australian Woodworker (#103). For those who missed the article, here is a picture of a precision mortising jig that I designed, and which I think is the next best thing to sliced bread. The jig enables you to accurately and repeatably position mortises on the workpiece and its stops enable you to make the mortise a precise width. To keep the fence parallel to the face of the workpiece, it runs on 1/8" parallel brass bars. To rout the grooves for these bars, I used a clamped-on parallel sided bar of aluminium as a fence.

The jig is made mainly of MDF, with a jarrah fence, micro-adjustable by means of a threaded rod. It costs only a few to make, apart from the cost of the gauge.

[silentC]

Rocker,

Looks the bee's knees. Any chance of posting some details, or do I need to hunt down the mag?

[Rocker]

If you want a copy of the article. e-mail me at [email protected]

[Rocker]

I forgot to mention that it is easy enough to use the main features of this jig, i.e. the parallel guide bars, the micro-adjustment by means of a threaded rod, and the gauge, to make a precision router-table fence. In fact I got the idea for this jig from Pat Warner's description in Fine Woodworking of a router table fence a few years ago.

[John G]

Hi Rocker,
Have just been reading your impressive article and have a couple of questions.

For the fence block (part E), you say to tap the 6mm hole. Are you using a normal (metalworking) tap to cut the thread directly in the jarrah?
Without a tap, could you instead just epoxy a suitable nut to the block? Or is there a reason to have such a long thread?

You use brass runners for the fence, but hardwood runners for the stop blocks. Any reason you couldn't use hardwood runners instead of brass?

Note: these are not criticisms of your great design. I'm just wondering if I need to use the exact same hardware.

[Rocker]

John,
I used hardwood guide bars for the stop blocks because a certain amount of play in the stop-block grooves does not matter. On the other hand, it is vital that the double guide bars for the fence are precisely parallel and that there is no play between the grooves in the fence and the guide bars. Wooden guide bars would be bound to bind, unless the grooves in the fence had a lot of play, owing to changes in atmospheric humidity. Metal guide bars are essential; but you could use aluminium bars, and they could be 1/4" thick to match 1/4" grooves routed in the fence and horizontal platform, I chose the 1/8" brass bars because they are easily available from Bunnings and I had a 1/8" router bit. The point is you need to match the thickness of the bar stock to an identical-diameter router bit used to rout the grooves.

Yes, I used an ordinary metal tap to tap the thread in the fence block; it is easy to tap the thread, especially if you chuck the tap in a drill press to start it off, turning the chuck BY HAND - NOT using the drill press motor. You probably could epoxy a nut to the block, as you suggest, but I thought that the glue bond might loosen after a time. I think it is anyway just as easy to tap the hole, as I suggest. I find it works very effectively, with very little backlash. I made the tapped hole relatively long in order to minimize wear and my jig still has virtually no backlash after three years' use.

[gatiep]

A way to strengthen the thread would be to tap the jarrah as u described, then remove the tap, blow out any dust and run some thin cyanoacrylate (super glue ) into the thread. Once that has set, screw the tap in to clean up the original thread.

That will make the thread as solid as you can wish for.

Cya

Joe


Have fun............................keep turnin

[Rocker]

I have recently made a new version of this jig using polythene ripped from a kitchen cutting board as the material for both the fence guide bars and the stop block runners. I cut the polythene a shade over 3/8" wide to fit into 3/8" routed dadoes, and fine-tuned the thickness of the polythene by laying it on a flat surface and planing off thin slivers with a jack plane, checking the width frequently with an electronic caliper, until the polythene strips could just be pushed into the dadoes in the MDF. In order to enable the wooden fence to run on the guide bars without excessive resistance, I used a very sharp chisel to pare the sides of the dadoes in the bottom of the fence until they were just wide enough to fit snugly onto the polythene bars.

The method of routing the matching pairs of dadoes is shown in a photo that I posted yesterday in the routing forum on the thread related to the ideal router table.

[John G]

And what was the conclusion from your mod?

Is there much difference between the brass and the polythene?

Is the polythene very much smoother? Is is more stable/less prone to binding? Is it worth doing it this way, given the hassle of cutting it to size? You would never use brass again?

[Rocker]

John,
I concluded that the polythene guide bars work just as well as the brass ones, but are presumably less durable in the long term. But then they are easily replaceable. There is not much difference between the two methods in the ease of getting a satisfactorily smooth-sliding fence. However, some people might not be able to get hold of 1/8" x 1/2" brass bar as easily as they could get polythene cutting board, and they might not happen to have a 1/8" bit for cutting the grooves for the brass bars; the polythene bars can be cut to suit whatever sized router cutter you happen to have for routing the grooves.

So the conclusion is: You pays your money, and you takes your choice.

[Glen Bridger]

Originally posted by gatiep
A way to strengthen the thread would be to tap the jarrah as u described, then remove the tap, blow out any dust and run some thin cyanoacrylate (super glue ) into the thread. Once that has set, screw the tap in to clean up the original thread.

That will make the thread as solid as you can wish for.

Cya

Joe


Have fun............................keep turnin


Joe,

I don't mean to shoot you down, but this probably won't work with the super glue. Cyanoacrylate glues are "anerobic" meaning they cure in the absence of air. You have to hold two parts together and expell all the air. Loctite products work the same (that's why the bottles are never full).
You could try Loctite Shaft & Thread repairer. Its an aluminium putty. Or an epoxy adhesive like Araldite. Never trying it myself.

Glen.

[Rocker]

It really isn't necessary to take any special measures to strengthen the thread if you use a hard hardwood like jarrah. I just use a little wax to lubricate the threaded rod and find that the thread works just as well as it would in metal.

[Sharpie]

I don't care what the others say

I received your drawing and instructions on how to make the mortise jig and I am looking forward to starting it

Thanks Joe (Sharpie)

[Caliban]

Me too
What sharpie just said, I mean.
Oh bugger, that doesn't make any sense either.
What I mean is I received Rocker's excellent plans and can't wait to start either.
Thanks Rocker.
Jim
ps Rocker, why did you sell your router table and your incra jig?
Was it because you have lost the faith and now use a table saw for tenons???

[gatiep]

Originally posted by Glen Bridger
Joe,

I don't mean to shoot you down, but this probably won't work with the super glue. Cyanoacrylate glues are "anerobic" meaning they cure in the absence of air. You have to hold two parts together and expell all the air. Loctite products work the same (that's why the bottles are never full).
You could try Loctite Shaft & Thread repairer. Its an aluminium putty. Or an epoxy adhesive like Araldite. Never trying it myself.

Glen.

Hi Glen,

I seriously question the anearobic bit, because cyano is packed with nitrogen or other inert gas filling the excess space in the container. The reason why you hold the two together is because cyano is NOT gap filling. I'll give you an example further down about bicarb. Actually water/moisture sets it off like a rocket.

The principle employed with the threads are that the cyanoacrylate seeps into the wood, mainly capillary action and with the moisture it sets off and becomes hard. That way the threads are much stronger. The best product to use to 'kick off' cyano faster is just water vapour, or dampen the two pieces of wood that you want to join. You'll actually see a white substance at the joint. That is also the reason why cyano ( special grade0 is used in surgery.
Get hold of a bit of bicarbonate of soda or baking powder and add a drop of cyano on it. (Do in well ventilated area). You'll see a bit of smoke as it sets off, due to the moisture content ( Being a retired chemist I can guarantee you that the bicarb has some H20 knocking around), resulting in a hard lump that is very difficult to break.
This is what we modellers use as a gapfiller in building R/C airplanes with balsa or even GRP. We regularly tap a thread into spruce or even good quality ply, run cyano in as I described earlier on, then clean the threads.
I guess if two 6 mm bolts screwed through 6 mm ply , treated as described, hold on the wings of a r/c plane doing over 100 k per hour, doing aerobatics, it will hold the router jig in question.

Regards,
Joe

[Dan]

The police also use "cyano" and water vapour for detecting finger prints on dark backgrounds, the same white substance that Joe mentions will form on the oils left behind when you touch something.

[gatiep]

Hey Dan,
What a great idea! Just imagine if the cyano was there before the criminal touched the object. He can be taken away with ready made proof of fingerprints.
In my previous life in my country of birth, we all had to do our bit, either conscripted or full time to the forces or the commandos or police reservists. I served in 3 reservist units and attended lectures on 'finger printing'....wow that was so interesting and some of the ways it was done was really ingenious. I remember the iodine vapour one for prints on walls etc, but guess it was before the cyano was used. Damn clever I must say.
I find it very interesting to see how a product gets developed for some use and then eventually there are so many other non related uses that it gets used for. Thanks for that one, will have to store that in the grey matter because being retired, I don't have a physical filing system anymore.


Regards
Cya
Joe

[Rocker]

Jim,
You asked why I sold my router table and Incra jig.

I sold the router table basically because it was not suited for its purpose. The fence was useless and the cast iron plate was much too thick, and the clamping system for the router was poorly designed. Its sliding table was poorly engineered. The new owner bought it for the substantial stand - not as a router table.

The Incra jig works well, but it has some limitations; you have to work in inches, because there is no metric version. It lacks independently adjustable subfences, so you cannot change the central aperture to accommodate larger router bits. However, it is excellent for smaller projects like boxes and so forth. I found however, that my version of Pat Warner's router table fence could fulfil all my router table needs, whereas the Incra could only fulfil some of them.

As for tenons, whilst it is perfectly possible to to rout them on my mortising jig, as described in the article, it is much quicker, and just as accurate, to cut them on my table-saw tenoning jig.

[Caliban]

David
Thanks for the reply, which on re-reading sounds like I was having a go at you. This isn't the case. I've carefully read all of your posts and I think you are a trend setter as far as Aussie jigs goes.
I'm very keen to try to build my own version of your fences and jigs. I really appreciate how you share your ideas.
cheers
Jim

[Rocker]

Would the Alex who e-mailed me for a copy of my article on this jig please PM me. When I tried to e-mail it to him, my e-mails bounced.

Rocker

[Rocker]

Got a rejection slip today from Popular Woodworking for my jig article. The reason given was

"Unfortunately, most of us on staff felt it was too similar to the commercial jigs that are already out there (the Leigh and Trend). Plus, we're swamped with articles just waiting to be published – our 2005 editorial schedule is pretty darn tight. Do try submitting it elsewhere, though."

I thought that was the whole point. My jig does the same job as the commercial jigs at a fraction of the cost. Ah, well. In fact, my jig is different in principle from the commercial jigs, which rely on guide bushings, with consequent inaccuracies.

I replied that I could understand them not wanting to upset their advertisers. Couldn't resist :)

Rocker

[silentC]

It's a conspiracy!

Oh well, their loss (or their readers' loss I should say).

[outback]

As a proud new owner builder of this jig, and its paertner, all I can say is I don't et it.

This jig is really simple to build, is cheap as chips to build and is inherently accurate.

As SilentC says, its the reader that lose out.

[echnidna]

There are other magazines

[silentC]

Yeah. Try this one: http://www.irishdancing.com/72.asp, they publish articles on Jigs.

[outback]

Is there something you should be telling us?????

[echnidna]

I think Outback's gotcha Silent, the jigs up

[silentC]

Just call me Twinkle Toes.

[echnidna]

So you gunna Tiptoe Through The Tulips in yer Santa Suit Silent?

[HappyHammer]

Where do you keep the magazines on other types of jigging?

HH.

[Rocker]

Well, I have also had knock-backs of earlier versions of the article from FW, American Woodworker, and Wood Magazine in the US. It will be published by Good Woodworking in England, but it would be good to find a North American publisher. Maybe there is a suitable Canadian magazine. Perhaps a Canadian member could advise?

Rocker

[DPB]

Maybe there is a suitable Canadian magazine.

One of the disappointing facts for Canadians is that although they (we) protest loudly about being mistaken for Americans, they (we) are quite willing to read American published mag's. As a consequence there are not nearly as many Canadian published mag's as there are Australian, even though the potential readership is almost twice that of our country (Australia).

I am not aware of any quality woodworking mag's produced in Canada for the Canadian market, though I would love to learn otherwise.

:(

[echnidna]

'I am not aware of any quality woodworking mag's produced in Canada '

Are there any quality Australian w\w magazines??

[scooter]

Ouch Bob.

I don't reckon we do too bad, considering the size of the readership the mags are catering to.


Cheers........Sean

[echnidna]

AWR might be ok if it didn't cater almost exclusively to the arty crafty lot.

[scooter]

Yeah, Bob, I know what you mean there.

I bought about 20 back issues of Aus Woodworker this morn at the market, dates from about '88 to '95 I think. It's interesting to read the old articles and ads, etc. Particularly how the scene has changed a lot in the interim.


Cheers.........Sean

[echnidna]

I do buy AWW once in a blue moon just to keep up with the adverts and suppliers but they are dropping off - must be the ads cost too much.

[DPB]

Hey, Gents, don't beat yourselves up. We do alright when it comes to publishing magazines. They may not be perfect, but at least they are Australian. Given the size of our market, with no potential of serving a larger market, I think it is rather remarkable the number and yes, even the quality of our mag publishing industry.

After all, this is a market smaller than southern California. I doubt that even our Yank friends would invest as heavily in producing magazines for their market if it was the size of ours.

[Farm boy]

do you need a plunge router or can you use a non plunge router (makita )

[Rocker]

Farm Boy,

You need a plunge router for this jig; in Australia, we don't retain the sentimental attachment to fixed-based routers that you seem to have in the US, so fixed based routers are almost unknown here.

Rocker

[Farm boy]

what do you mean calling me a non australian it is floraville, a suburb of lake macqurie :)

[Rocker]

what do you mean calling me a non australian it is floraville, a suburb of lake macqurie :)

Oops; sorry, sounded more like a suburb of Miami; and it doesn't feature in the index of the Touring Atlas of Australia. Perhaps you need to specify NSW.

Rocker

[echnidna]

What part of Texas is Lake Macquarie in ??????

[echnidna]

apology but it fitted in well !!!!!!
:) :) :) :) :) :) :) :) :) :rolleyes: :rolleyes: :rolleyes: :rolleyes:

[Grunt]

Oops; sorry, sounded more like a suburb of Miami; and it doesn't feature in the index of the Touring Atlas of Australia. Perhaps you need to specify NSW.

See, this BB is educational.

[Harry72]

Hey Rocker I made your jig thanks for the plans... I've only made it out of mdf to test it 1st, I might make one from steel so it will last forever!
I dont think I need the dial gauge, as without it Im still getting good accuracy(with in .002mm)I'll save the guage for setting my thicknesser blades instead:D.
The second pic shows what I ment by using brass angle, it works well with only .001mm of skew on the side stops(with the assistance of CRC!), the main guide has a fair bit of skew so Im going to remake it with tighter slots. I cut the slide slots with a 1/4" straight bit 1st then glued in shims to get the correct slot width.
The 3rd pic you'll see the fix for a boo-boo:eek: I made, I didnt check my tri-square ... it took 4 visits to the hardware stores to find a good square square :mad:doh most of them didnt even know how to check one... its new of course its square they'd say:(. One even got mad when I put pencil lines on his counter top(he he he, got me some payback!).

[Rocker]

Harry,

That is a very interesting version of my jig, but most of us don't have access to CRC. I have been wondering about how to make the jig in aluminium, in order to enable the horizontal platform to be made thinner (and thus maximize the depth of the mortice that can be routed). But I wasn't able to come up with a way of making it that the ordinary hobbyist, without access to specialised equipment, could use. Maybe, if you could come up with an aluminium version it might be a commercial proposition to rival the Trend and Leigh jigs.

If you made it in metal, maybe you could build in a vernier scale that would provide high accuracy without the need to have a gauge.

Rocker

[Harry72]

An all aluminium jig would be good as it would be very light, too make it would be a different story, idealy I would redesign it so the whole top plate would traverse on the upright support with a fixed fence for the router base to guide against, this way the top plate could be made quite thin say 2mm with braces along the outer edges. The top plate wouldnt need all the excess behind the fence guide either...
Also a extra adjustable fence along the front to gain the best control while cutting mortices would be good to limit any miss cuts.
Im finding the limitations allready like you say the plunge depth is a problem with a 5/16 Sp'upCut bit 40mm seems to be the max cutting a mortice, Im loosing 16mm to start with!
3mm Mild steel would be the go to make a prototype or 3.
Hmmm its got me thinkin about tinkerin... but alas must make some furniture 1st keep the SWMBO happy, she had her 1st neice born 18min's after Xmas so I'm making a nice blanket-X-toy-X-glory box for the baby, the name they gave her is "Lauren Kate" might even carve her name in the top!(sure beats flowers)

[lesmeyer]

Hi Rocker,

is the hotmail a/c you mention earlier in this thread still active?
I am interested in the plans for the jig as I wish to involve myself more with mortice and loose tenon techniques.
Regards
Les

http://www.woodworkforums.ubeaut.com.au/images/icons/icon10.gif

[Rocker]

Les,

Yes; e-mail me, and i will send you the plans.

Rocker

[Harry72]

Rocker, how much free play should I allow when cutting M&T's, as tonight I glued up some M&T's and ended up spilting the wood through "hydraulicing"(flogging a drag racers term...). The joints slipped together well without any fuss with outglue, when I pull them apart I get a popping sound(like when pulling your finger out of a glass bottle).
Those joints had a clearance of .02mm, obouviously thats not enough space to allow glue(pva)to move thoughout the joint.
So whats the go, like .5mm overall(.25 each side)?

Ps, I got too many zero's in my post above I said .002 when I ment .02, Hmmm working in thou's of mm on woodwork!

[Rocker]

Harry,

I aim for clearance of about 0.03 mm on either cheek of the tenon - i.e., the tenon about 0.06 mm thinner than its mortice. I avoid the hydraulic problem by not rounding the ends of the tenon to fit the rounded ends of the mortice exactly, but slicing facets off the ends so that there is room for the glue to escape, as in the diagram below.

[silentC]

Would you also leave the tenon a few mm shorter than the depth of the mortice so that the tenon does not bottom out and leaving the excess glue somewhere to go? ;)

[Rocker]

SilentC,

Yes, that too; but space at the bottom of the mortice will not solve the problem, unless there is some channel by which the air trapped in the mortice can escape, as you push the glue-covered tenon, which is acting like a piston in a cylinder, into its mortice.

Rocker

[Harry72]

Ah so leave some sort of "relief" for the glue to go.
Thanks Rocker

[LineLefty]

Received the plans Rocker thanks a lot. I might have a go at the Lite version when I get some time. Milling the spline might be a bit of a hurdle though.

In other news, how do you do the mortices in the curved pieces of your chairs?

[Rocker]

Adam,

If you don't have a table saw to cut the spline, you could just rout a 3 mm deep, 6 mm wide, groove in the underside of the horizontal platform, and rout a rabbet on the top edge of the vertical support, so that there is a 6 mm thick 3mm long tongue left to fit into the groove.

Rocker

[Rocker]

Adam,

I omitted to answer your second question, on how to cut mortices on the curved rails of my chair. There are two options:

Option 1. You can cut and fair the concave face on the front of the rails, and then rout the mortices by clamping the rail in a vice with a curved caul, and using a curved fence attached to the router's edge-guide. This method, of course, produces slightly curved mortices, but the curvature on a 30 mm long mortice is not noticeable.

Option 2. You can cut and fair both the back and front curved faces on the rail and then clamp the curved rail onto my morticing jig, so that the mark in the centre of each mortice in turn registers with the centre-line of the jig. This second option is easier.

Rocker

[Rocker]

I have finally managed to draw the jig in 3D in TurboCAD. I attach four different views.

Rocker

[Grunt]

Great work Rocker. What do you think of TurboCad? Mrs. Grunt is a student and I am thinking of getting a student copy of it.

[Rocker]

Grunt,

I like TurboCAD Pro very much; I think it would be well worth getting for a student price. The De Luxe version is a bit of a rip-off in that almost all the sample files necessary for understanding the 2D and 3D Training guides are missing from the CD of that version, which makes it hard to learn properly.

You definitely need the training guides as well. It would be virtually impossible to learn the program from the Reference Manual alone. If Mrs Grunt does get it, I shall be happy to pass on a few tips on things that are not made clear in the Training Guides.

Rocker

[jow104]

Hi Rocker, That looks very impressive to me.

Can I or we assume you will give free lessons, or an idiots type sheet ;) ;) ;)

[Rocker]

John,

I am afraid there is no substitute for RTFM (Read the F****** manual) :)
Anyway, I think I have only managed to scramble about a third of the way up the learning curve, so it would be a case of the blind leading the blind.

Rocker

[paulver]

Hello All,

It only took me about a year after I actually requested the plans from Rocker, to actually pull my finger out and build it, but I'm really happy I finally did.

Last year I built a baby change table for some close friends. For this I used dowels. To say the least it was slow and tedious, with me having to mark each individual join etc. Some other friends were due their first child this year and again the call was made for another change table. After the grief of using doweled joints last time, I thought that mortices should be attempted this time.

All the hardware came from Bunnings. Knobs, threaded rod, t-nuts came to about $30. For the timber, I bought three 1.5m Jarrah pickets for a total of about $5.50. All I did was laminate pieces to achieve the desired thickness / width with little waste and next to no cost. Obviously a little more time in creating the various resultant dimensions, but hey, I'm a cheapskate and would rather save a few dollars and a tree or two. The MDF I got from Mr Ply & Wood, as they can supply smaller off cuts, instead of me having to buy a great big sheet for only a small amount needed. About another $5.50 there.

Since it was so long between me receiving Rocker's plan and actually building it, I was able to take advantage of his advice in a subsequent revision of the design. This included the reinforcing for the platform, the spline for the join and the use of the kitchen chopping board for the fence guides. (wasn't able to find any brass bar anyhow...) I skipped the dial gauge, and instead will rely on a vernier or accurate ruler.

For the table I had to make thirty mortice cuts. Once I had the jig set, and a couple of test cuts made, I think I was able to get through all 30 cuts in a bit over an hour. Once the workpiece mortice centreline was aligned with the jig, the cut was easy and straight forward, with little chance of error. Since every mortice cut was identical, there was no issue with trying to match a tenon with a partner mortice. The assembly was an absolute piece of cake, with every join being both smooth and snug.

The jig and outcome change table are attached.

Rocker. Thanks very much for your contribution to us all with your jig. It's made life much easier for me.

Paul.

[Gazza]

Hi,

I just got myself a router and want to use it to make mortice & tenon joints.

This jig seems to be very popular.

I sort of get how it works but would someone mind explaining how it is used ?

I don't see how you control the width of the mortice.
eg: making a 3/8th mortice with a 1/4 bit, etc.

Which is considered easier, rounding the tenons or squaring the mortice.

Can this jig be used to route mortices in the end grain of boards ?

Thanks

[silentC]

I don't see how you control the width of the mortice.
eg: making a 3/8th mortice with a 1/4 bit, etc.
To make a 3/8" mortice, you use a 3/8" bit. The jig only has one fence, so you can't make a mortice wider than the bit you are using.


Which is considered easier, rounding the tenons or squaring the mortice.
There is a lot of debate over this. Rounding the tenon is probably quicker. If it's a through mortice, it depends on the look you want.


Can this jig be used to route mortices in the end grain of boards ?
Yes.

Rocker gives details on how to use the jig in his plans (I think).

[jow104]

Gazza:

The last M/T job I did 192 joints ( 12 planters) which were made using a pine softwood I found that I did not have to round over the tenons I just whacked them in with glue. No test fitting apart from the first cut joint to ensure my jig had cut correctly.

Most probably would round over tenons though in an hardwood or firmer type softwood.

[Grunt]

John, you are a brutal man.

Whacking them poor defenceless joints.

[LineLefty]

Adam,

If you don't have a table saw to cut the spline, you could just rout a 3 mm deep, 6 mm wide, groove in the underside of the horizontal platform, and rout a rabbet on the top edge of the vertical support, so that there is a 6 mm thick 3mm long tongue left to fit into the groove.

Rocker
Rocker, A long time ago I know, do you find that a simple glue and screw butt joint is not strong enough? What about reinforing with corners brackets (on the short side) instead of the spline?

[Rocker]

Gazza,

Ideally, as SilentC says, you should use a 3/8" bit to rout a 3/8" mortice; but if you don't happen to have a 3/8" bit, you could rout a 1/4" mortice, then move the fence 1/8", and widen it to 3/8". Not that hard; but you would need to ensure that your feed direction was right on the second pass.

Yes; the jig can be used, very effectively, to rout mortices in end grain.

Adam,

The point of the spline, or tongue and groove joint, is to ensure that the vertical support of the jig, to which the workpiece is clamped, is exactly parallel to the fence. With a simple butt joint, it would be hard to ensure that the vertical support was properly aligned.

Rocker

[outback]

I just whacked them in with glue.

Wow, you must have strong glue, or sloppy M&T's :D


I reckon it's best to use a whatever size mortice you want sized bit, rather than stuffing around moving the fence.


I suggest you don't drop the jigs from height. :(

[jchappo]

All the hardware came from Bunnings. Knobs, threaded rod, t-nuts came to about $30. For the timber, I bought three 1.5m Jarrah pickets for a total of about $5.50.
The jig and outcome change table are attached.



Paul.
Paul, both the jig and the table look great, but which section in Bunnings did you get the tri-knobs?

John

[LineLefty]

Gazza,

Adam,

The point of the spline, or tongue and groove joint, is to ensure that the vertical support of the jig, to which the workpiece is clamped, is exactly parallel to the fence. With a simple butt joint, it would be hard to ensure that the vertical support was properly aligned.

Rocker
Ahhh, I see.

When you first see these jigs, your first impression is always that is is so absurdly simple. But it's not until you start building it that you find these things out and have to go through 10 iterations before getting it right. In this case, you've done those iterations for us (thanks) as has derek with his beltsandergridersharpenerhoner.

[DPB]

I built Rocker's Mortising Jig to make his rocker.:)

http://img218.echo.cx/img218/2522/pic16a8hw.jpg

It now occurs to me that I was operating from the wrong side of the jig.:( I believe that the direction of the revolving router bit is such that it is best to cut the mortise from right to left with the fence between the operator and the router. The revolution of the router bit would then force the router against the fence.

I moved the router from left to right with the fence on the other side of the router, as is shown in Paul's post above. Unfortunately, on a couple of mortises, the revolution of the router bit pulled the router away from the fence making a sloppy mortise.:o (I repaired these by filling the mortise with a timber plug and re-routing.)

So, my question is: "Is my conclusion that you use Rocker's jig with the fence between the router and the operator correct?":confused:

[Rocker]

Don,

You are absolutely right. I am afraid my description of the operation of the jig does not spell it out, since I assumed that anyone sufficiently router-savvy to use the jig would know the correct feed direction when using a fence to guide the router. I have now modified the jig article to specify which side of the jig to stand.

There is a picture of the jig in use here in post #54: http://www.woodworkforums.ubeaut.com.au/showthread.php?t=9500&page=4

Rocker

[DPB]

I knew about the bit rotation and the affect it has on the direction of travel, but somehow to me, the jig just looked like it should be operated on the side 'wrong' side. I guess Paul jumped to the same erroneous conclusion. It would be interesting to learn from him whether he experienced the same problem that I did.

[paulver]

Paul, both the jig and the table look great, but which section in Bunnings did you get the tri-knobs?

John

Hi John,

The knobs are just in the builders hardware area. I think most stores are arranged the same, so it's near the other fasteners etc. I'll go for a walk at lunch and check which isle number at the local store.

Paul.

[paulver]

John,

The parts are in aisle 4 at the Bunnings store in Wollongong. Builders hardware. The brand is Cornall. They live in the same area as the rubber stoppers that go on chair legs etc. The T-nuts are in the same area.

I'm guessing that Bunnings lay out all their stores in a similar fashion, so hopefully you'll find them.


In regard to the use of the jig. I don't have a tail vice like Rocker, so had the jig in the front vice. I stand to the left of the jig (workpiece window on the right as I'm looking at it) and plunge the router at a stop closest to me moving the router away from me. In this way the fence is on the left as I'm working. This method (fence on the left) is from an instructional poster that I got from a Les Miller demo at the Timber show awhile back.

Regarding rounding tenons vs squaring motices. For the change table I built, I cut square tenons and then chiselled each corner making a half hexagon like this

/-\
| |

This allowed the tenon to fit neatly in the mortice, and allowed some space for glue squeeze out. This took all of three seconds per corner. About 20 seconds per tenon. Much quicker and easier than the other two options. I think Rocker actually suggested this idea to me in the first place, so I can't claim credit for it.

Hope this helps.

Paul.

[MikeThePom]

I have modified Rockers morticing jig for my workshop and thought I might share some of the ideas with the forum.

Firstly I have the workpiece flat on the workbench (I use a 20mm thick MDF board so that it is a level surface) raher than clamping in mid air. The jig itself is in 2 parts, the top can slide back and forth so that the 'zero' position for the router bit is in the middle of the stock. The bottom part of the jig has a side support I can use to clamp to if required and also a 150mm square cut out so that long stock can poke through. I used 4mm aluminium plate for the stops and 10mm wide 4mm thick aluminum strip to keep the stops parallel and perpendicular to the front edge. At the moment I have not added rulers to the top but intend to when I can find a high contrast stainless steel version.

In use I have not yet had to clamp the workpiece as the weight of the jig and the vice clamping has sufficed, however, if needed I will add a same sized piece of stock under the back right corner and use a deep throated clamp to hold it in place. It doesn't have the micro adjuster of Rocker's original but so far I haven't needed it plus I would have to adjust both font ann back stops to keep the mortice centered in the stock. I made a couple of brass faced 'setup' blocks that are put in the opening so that the centre lines on the top of the jig line up with centre lines on the stock.

There are hardwood runners on both sides of the jig to ensure that the top moves perpendicularly to front edge. I probably not explained myself very well but hopefully the pictures will make up for it.

Image 1 full jig view from front
Image 2 full jig view from left side
Image 3 base from back
Image 4 sliding top of jig
Image 5 'setup' blocks

Regards

Mike

P.S. Before I get flamed for this I have already checked with Rocker and he is happy for me to add this!

[MikeThePom]

Can anyone tell me why don't the attachments stay in the same order as shown in the Manage attachments window ?

Mike

[jow104]

MTP

I myself always upload my pictures these days to a host (photobucket) and then post pictures full size.

You have not yet stated that the mortices were 100% successful ;)

[MikeThePom]

So far yes 100%

[Rocker]

Mike,

Your jig certainly looks a bit easier than mine to build, but, in its present stage of development, you would not be able to obtain the same precision with it, since it lacks scales, a dial gauge, and micro-adjustment.

I considered using your method of guiding the stop blocks, but was dubious whether it would be feasible, if using MDF for the platform, to attach the guide bars firmly enough to ensure that there would be no play between them and the stop blocks.

By the way, it is not necessary to have fences on both sides of the router to guide it. So long as you feed the router in the correct direction, the bit rotation will hold the router firmly against a single fence, as in my jig.

Rocker

[MikeThePom]

Rocker,
The two stops one on either side is so that I can set the width of the mortice before I start cutting.

Regards

Mike

[Rocker]

Rocker,
The two stops one on either side is so that I can set the width of the mortice before I start cutting.


Mike

Mike,

I normally just use standard widths, corresponding to the available diameters of spiral bits, for my mortices. In the rare instances where I need a mortice thicker than 1/2", I use a spacer. So, if I want to cut a 7/8" thick mortice, I make one pass with a 1/2" bit; then I put a 3/8" spacer against the fence, and make a second pass, this time feeding the router in the opposite direction to the first pass. In this way, a second fence is not needed.

Rocker

Rocker

[Rocker]

Jow, check your PMs.

Rocker

[jow104]

Jow, check your PMs.

Rocker

OK Rocker, message received.(@ 8 am BST)

(my internet service is restricted and finishes at 4pm BST each day)

[junkboy999]

Both you guys have nice jigs.

I have only made a few things where I used tenons and motise. I would love to use some more in future prodjects. I would like to build a jig that has the abliity to repete a mortise and tenon that I might of made last week with out a lot of set up again. I owen an Incra TS fence and relay on the fact that I can recut another peice after messing up one with out having to get a tape out and meausing anything.

Rockers jig has a dial for acurey but I was wonderin if there would be a way to make a drop in Block or template for quick set up for you most commenly use seting ( lets say 1/2 or 3/4" stock for me )

Mikes Jig looks like it would be easy to make a drop in template for seting it up fast. It just looks like it would need a way to refind the center, even with a template in use. Just say SWHBO uses one of your cut peices as a planting stack or the Dog thinks it is a bone.

Would eather of your jigs be able to cut a fourth table skirt with the first 3 allready glued in place so you cant use them for a guide, to make it harder you have allready taken your Jig off the vice or table, reset it to "0" position or a storage position.

Remember I use to be in the mititary and we used hammers and rocket launchers with the instruction printed on the side of them.

I have seen the Leigh Ind. Mortise & tenon jig in use at a wood show and watch the guy make two joint. the secound one did not work because he goffed and just shureged if off. I know the Trend has one too but have not see one in use. Somthing like the trend with drop in templates is what I would like to build.

[Rocker]

Junkboy,

It is easy to calibrate my jig so that you can read the distance that the mortise is from the face of the workpiece directly from the dial gauge. If you want an article on my jig, PM me your e-mail address. I even have a Murcan version in inches, cubits, :) etc.

Rocker

[outback]

Junkboy, I thouroughly recommend Rockers version in bees dicks. The hard part is convincing that many bees they don't need them anymore! :D

[himzol]

Mine is well on the way,

I did modify some of the measurements to suit materials I had at hand as well as use 12mm Aluminium tube for the runners, otherwise I've stuck to Rockers design.

I will probably have to wait a little while before fitting the dial gauge (cost), but it will definately be fitted.

I'm planning on building a dining table out of English Oak and this jig will be invaluable.

Thanks Rocker for sharing the idea with everyone here.

Himzo.

[MikeThePom]

When I made my changes to Rocker's morticing jig design my intention was to make it able to cut tennons as well as mortices. My original modification didn't work out so I put my thinking cap back on and came up with the following:

I cut a piece of MDF to act as a clamping plate, using the top from the modified jig and an adjustment bolt it enables me to cut perfect tennons.

The first thing to do is mark centre lines in both directions on the end of the stock. Then with the top removed and the clamping plate on the workbench I lightly clamp the workpiece in the bench vice and move the clamping plate so that the centre line on the clamping plate aligns with the centre line on the stock and clamp the clamping plate to the workbench. At this point it is importent to make sure that the workpiece is level with the upper surface of the clamping plate and perpendicular.

Now attach the top and using the setup block move the top forward and backwards until the side to side centre line is along the setup block. The aluminium sliding plates on the top are now set so that the correct width and thickness of mortice is cut. The depth stop on the router will set the length of the tennon. If you need a longer tennon than the distance between router bit and workbench use some timber/MDF packing to raise the jig off the bench. I have not used it for a serious job yet but have cut some trial pieces and they are beautifully clean shouldered, in the past I have usually had to hand tidy each one but no longer...

Regards

Mike

photo1 checking workpiece is vertical and level with top of clamping plate
photo2 setup block to adjust top so that centre lines match up
photo3 setup complete (dust extraction is under the top at the moment but I may tackle this later)
photos 4&5 test through mortice using jarrah offcuts

[Dennis O]

I saw Max's gear at the www show. Can't rember the exact price but astonishingly cheap. Check the website.

Rocker - your jig is next on the list!

[RETIRED]

Picture up again David.

[Felvo]

Rocker, This is truly a nice looking bit of kit. I have sent you a PM asking about the plans, etc, but I had to let everyone else know what I thought about your jig.

Felvo

[Rocker]

For those hardy souls who have ploughed through seven pages of posts, the plans for my jig can be downloaded free from my blog; see below.

Rocker

[jow104]

For those hardy souls who have ploughed through seven pages of posts, the plans for my jig can be downloaded free from my blog; see below.

Rocker

Thanks Rocker, but it actually made interesting reading looking back through those usernames, unfortunately some of us are no longer around.

[Rocker]

Thanks Rocker, but it actually made interesting reading looking back through those usernames, unfortunately some of us are no longer around.

Jow,

Yes, I believe Gatiep is no longer with us, and I haven't seen posts by DPB or Linelefty, or DanP for some time; hopefully the latter three have just moved on to other interests, rather than shuffled off this mortal coil.

Rocker