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View Full Version : Router Modifications to Allow Cutting of Woodworking Joints



EddyCurrent
22-12-2014, 03:52 PM
This follows from my build log discussion on the subject; http://www.mycncuk.com/threads/6565-Ready-Steady-Eddy?p=64514#post64514

Sequence of events;

1. cut hole in table to leave approximately 200mm square hole for workpiece.
2. Make table insert to restore bed to one flat surface.
3. skim top of table insert with router.
4. manufacture plywood support arms, 50mm wide, 70mm high
5. drill all mounting holes using machine while keeping same zero datum point.
Holes in, table, table insert, support arms. Counterbore support arms holes and table insert holes. Fit 8mm threaded inserts into table.
6. Check machine to ensure spindle is vertical in all planes. I attached an engineering square to a 1/2" cutter and used a piece of 6mm plate as a feeler gauge. Checked all round 360 deg. circle.
7. bolt support arms to table, skim front faces and top using machine.
8.Cut out and attach workpiece support cheeks. Cutaways allow 100mm throat clamps to be used for both narrow and wide workpieces. Three clamping positions are available and workpiece can be positioned in X direction or Y direction.
9. Check support cheeks are vertical using a straight edge from spindle and try-square from table top, glue and screw in position.
10. Seal all bare wood with clear lacquer.

The not so nice looking slots near the top of the support cheeks are to allow fixing of a T slot rail, which is not yet in my possession, this will allow attachment of jigs such as a 45 degree ramp.

Changeover from flat bed to jointing jig and vice versa is under 1 minute (assuming socket and screwdriver are on hand)

I lost some of the T slot due to this modification but it's not really a problem

Before.

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mike os
22-12-2014, 05:12 PM
that looks useful

T0rnado69
22-12-2014, 05:29 PM
ohh bessey clamps....
gotta love em :)

are you planning on some dovetail cutting :)

EddyCurrent
22-12-2014, 05:51 PM
are you planning on some dovetail cutting :)

Yes but I bet I can cut them by hand faster.

JAZZCNC
22-12-2014, 07:29 PM
Eddy thought that ages ago before building machine it was mentioned about making the gantry go past the end of bed so edge work could be done. Didn't you do this.?
Or have you got another reason for doing it this way.?

EddyCurrent
22-12-2014, 07:43 PM
Eddy thought that ages ago before building machine it was mentioned about making the gantry go past the end of bed so edge work could be done. Didn't you do this.?
Or have you got another reason for doing it this way.?

Can't remember seeing that, or thought it wasn't needed, anyway didn't do it. I don't have a big use for this but it was a good little project.

JAZZCNC
22-12-2014, 07:46 PM
Yes but I bet I can cut them by hand faster.

Bet you can't to same accurecy and do it repeatably for say 12 draws.!

Regards your fixture Jig do you realise that you can create and save a Fixture offset for this so you don't have to mess around finding Zero.?

EddyCurrent
22-12-2014, 07:48 PM
Regards your fixture Jig do you realise that you can create and save a Fixture offset for this so you don't have to mess around finding Zero.?

Yes, plan using G55

mitchejc
22-12-2014, 08:04 PM
Great job, looks very nice and its a handy feature to have on a router.

T0rnado69
22-12-2014, 09:05 PM
maybe

but i would say, its a bit hard to cut them quickly
with a cuppa in your hand or a cold beer :)

Ger21
23-12-2014, 02:15 AM
Yes but I bet I can cut them by hand faster.

Not if you have the right software. :toot:
This only took 5 minutes. It would take longer just to lay them out if doing by hand.

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gavztheouch
23-12-2014, 12:35 PM
Cool nice mod Eddy. What do you make with your machine? Furniture?

EddyCurrent
23-12-2014, 03:51 PM
Cool nice mod Eddy. What do you make with your machine? Furniture?

Firewood :thumsup:

gavztheouch
23-12-2014, 07:26 PM
Firewood :thumsup:

:highly_amused: Ha ha, well at least you will have plenty of supplies for that workshop stove.

Allan
23-12-2014, 09:10 PM
I'm new here and don't want to hijack your thread. I hope you'll excuse my question which is related to your thread. I'm planing on making my first CNC router with the initial goal of cutting woodwork joints. Until I read your post I was considering making a machine with a spindle mounted on a bearing to allow it to rotate from being vertical or horizontal. My thoughts were that I would find it easier to clamp and align my workpieces horizontally to a raised work surface on the bed than vertically. This would also allow me to machine joints in the ends of long workpieces (2 m in length for beds for example). Have you ever seen a spindle like this and am I mad to consider it?

EddyCurrent
24-12-2014, 05:38 AM
You mean like this ? http://www.cnc-toolkit.com/gantry_router.html

JAZZCNC
24-12-2014, 08:41 AM
My thoughts were that I would find it easier to clamp and align my workpieces horizontally to a raised work surface on the bed than vertically. This would also allow me to machine joints in the ends of long workpieces (2 m in length for beds for example). Have you ever seen a spindle like this and am I mad to consider it?

Not Mad but not as easy has you think to do and keep a ridgid and accurate machine. The link eddy posted is to a 5 axis machine that is both expensive and complex to build, let alone generate G-code. Certainly not something I would advise any one new to CNC to dream about taking on for a first machine.!

The problem with rotating spindles is the accurecy needed in the rotation device to keep the spindle so it's perfectly aligned in 2 planes. Sounds easy to just flip the spindle horizontal then back again.! But in practise there's quite a lot of time invested in setting up your spindle so it cuts true in both X & Y planes and gives a nice flat bottom cut parallel to the bed surface.
So any spinning device will need to be very well engineered so it's repeatable if want any decent accuracy. Then you have the fact you'll need to spin it 90deg in 2 planes to be of any use which adds to the complexity.!!

While I see why or the appeal of what you want then NO it's certainly not something you want to be taking on for a first machine believe me.! . . . The machine design Eddy used is a good tried tested design with one exception in that it he should have listened to his uncle Jazz and made the top rails longer. . .:hysterical: (Soz eddy couldn't resist) and used the end of the bed for clamping.!

Allan
24-12-2014, 12:18 PM
Thanks Eddy and uncle Jazz. I really like the system you built into the base of your machine Eddy - thanks for sharing it. The idea I had for rotating the spindle is as uncle Jazz describes. I'll put together a drawing and post it on a new thread where hopefully some members will throw some mud at it. I was thinking of using strong and accurate bearings in a housing like the fixed end of a ball screw. Thanks again for your inspiration and showing what you've done. I'll have a look at Eddy's build log.

EddyCurrent
24-12-2014, 01:45 PM
The machine design Eddy used is a good tried tested design with one exception in that it he should have listened to his uncle Jazz and made the top rails longer. . .:hysterical: (Soz eddy couldn't resist) and used the end of the bed for clamping.!

You won't be laughing when I put a rotary table in the same hole :thumsup:
Allan, with regard to your idea, I would sort out how the software is going to work first.

EddyCurrent
24-12-2014, 02:16 PM
Not if you have the right software. :toot:

Gerry, I hadn't forgot about your software but l'm writing some applicable scripts for CamBam first, if the outcome is bad however I know where to come.

JAZZCNC
24-12-2014, 04:52 PM
You won't be laughing when I put a rotary table in the same hole :thumsup:
Allan, with regard to your idea, I would sort out how the software is going to work first.

Not laughing at you mate think you have done a marvelous job and credit to you for an old duffer. . .Lol
By the way that same Rotary table on the end is just as functional if not more because you have a lathe as well as 4th axis if done right.!

EddyCurrent
24-12-2014, 09:54 PM
Not laughing at you mate think you have done a marvelous job and credit to you for an old duffer. . .Lol

I know you're not laughing, get some London Porter down yer gob, from one old duffer to another :beer:

EddyCurrent
04-01-2015, 03:36 PM
I've been getting back into some programming after a very long time, I forgot how much fun it was so haven't been in the shed for a week.
Anyway I've written a script for CamBam for cutting Finger Joints or Comb Joints and hopefully there will be more to come.
I've attached it here but any future updates need to be downloaded from the CamBam forum; http://www.cambam.co.uk/forum/index.php?topic=4269.0
Just look for this title; Woodworking Joints - Finger Joints Script

The zip file should be extracted to your CamBam scripts folder where it will create a sub folder with the form images in it.

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EddyCurrent
05-01-2015, 12:41 PM
Second attempt, very pleased, this was the 'Antenna' preset pattern across a 58 mm width, 10mm thickness, cutter size 3 mm diameter. cutting time 5 minutes total.

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longy
05-01-2015, 01:43 PM
Looking good Eddy nice work, a tip to avoid any break out on the back edges. Like at the top edge on the right hand bit of timber shown in the pic, use a bit of scrap even MDF to support the timber edge that is being cut. Another thing is to leave the finger slightly longer then sand down flush after gluing up.

Try doing something like a dovetail + finger joints, I would be interested to see how that comes out.
Mike :)

EddyCurrent
05-01-2015, 02:26 PM
Looking good Eddy nice work, a tip to avoid any break out on the back edges. Like at the top edge on the right hand bit of timber shown in the pic, use a bit of scrap even MDF to support the timber edge that is being cut. Another thing is to leave the finger slightly longer then sand down flush after gluing up.

Try doing something like a dovetail + finger joints, I would be interested to see how that comes out.
Mike :)

Yes, thanks, I didn't bother about breakout this time because it was just a test and I didn't think it would turn out so good. I did leave an allowance for sanding flush, it's called Cleanup Allowance in the script, I left 0.1 mm but next time I might leave 0.2 mm.
Dovetails might be next but I think these days they are over rated, I read that the only people who look for them are those interested in making them, that's why I went for finger joints, thinking the pattern was more eye catching to your regular punters.

suesi34e
05-01-2015, 05:46 PM
Hi all,

I don't know much about CNC machines but I like the table cut out idea a lot and can see it could be very handy for many jobs. I look forward to hearing more about it.

Thanks

Suesi

GEOFFREY
05-01-2015, 08:55 PM
Looks good Eddy. G.

longy
08-01-2015, 08:25 PM
Dovetails might be next but I think these days they are over rated, I read that the only people who look for them are those interested in making them

Dovetails are stronger and used mainly on drawers as when the wood shrinks the joint holds better, having said that with todays glues and kiln drying finger joints have started to out perform the old dovetail in strength and done correctly they can look as good as dovetail joints. Modern joinery has come a long way with most large and small projects being cut on CNC's of which I got to see a little one today.http://www.mycncuk.com/attachment.php?attachmentid=14344&stc=1
Not to big for a 5 axis machine with a cutting area of 1.5 x 7.5 Meters.

Did think about sticking it in the back of the car when no one was looking, but would need a slightly bigger workshop. LOL

EddyCurrent
08-01-2015, 08:59 PM
Interesting video here; http://www.finewoodworking.com/how-to/video/joint-strength-test.aspx


Also I've updated the script, it does stock with different thicknesses and can work in the X or Y axis, here's a test today. I keep forgetting to specify an odd number of fingers in order to get a symetrical pattern on each piece. :stupid:

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GEOFFREY
09-01-2015, 11:25 PM
Looks very good Eddy. Geoff.

JAZZCNC
10-01-2015, 09:47 AM
Man of many talents looks very nice and professional Eddy. . :applause:

Think I may have to take another look at Cambam it's been a while since I played with it.!

EddyCurrent
10-01-2015, 11:07 AM
There's talk on the CamBam forum about a new version some time this year. It's a great piece of software for anyone who wants to get in among it rather than a 'glossy brochure' approach.