Thread: Leigh Problems

Originally Posted by haggismuncher

I'ts my job over the long summer holiday from school to look after our treasure, who is actually great fun but has a pathalogical hatred of power tools. He walks around the workshop with hands over his earmuffs asking "Are you finished yet?"
He already has his own workbench and has rounded up a pile of tools, (some real some plastic) including an old hand drill which he is fascinated by.
So he is on the right track

My son was the same, he's now 25, he used to follow me in the garage when I used to fix and service our cars. The same i got him a little tool set and he started fixing his bikes, progressed to motor bikes and then restoring classic cars four of them ( 2 x 1963 chevs an HQ monaro 2 dr and 1964 chev impala). During his snr yrs at school picked up woodwork and now his in the motor bike trade and very proud of him and I also miss those early yrs...enjoy him and encourage him

Originally Posted by Cruzi

Carbatec stock the CMT 8mm shank, 8mm cut bit suitable for Leigh jigs.

Part No 191-081-11

Thanks Cruzi,
Just been to the big C and bought the CMT bit and just tried it............... 10 out of 10
Thanks again
Jack

Finally got time to myself in the workshop, (apart from the whole family turning up with a range of ear protection on).

I followed everyones advice:

• Backing board
• careful feed rates
• back routing when needed following instructions from Leigh
• One router used in the same orientation
• Sorry can't afford a spiral bit yet but it is on the wish list, after dust protection.

I managed to improve on my last efforts considerably. Minimal gaps in the joints. However, I am using a fixed base router (Makita 3601b), I noticed that the bit moves off centre whilst I am setting the depth and the result is a bit well off centre in the guide bushing.

My question is, does this matter?

so long as I:

• Minimise it as much as possible by trying as much as I can to keep the bit set in the middle.
• Keep the router orientated in the same direction.

Anyway, most importantly I had a happy customer, my son can now reach the toilet as the first project was a simple dovetailed stool for him to use now he is toilet training.

Chris

Hi Haggismuncher,
Once you do use the spiral bit you'll be amazed at the results as I was, its sooooo easy and smoooooooooooth
Rgards
Jack

Originally Posted by haggismuncher

I am using a fixed base router (Makita 3601b), I noticed that the bit moves off centre whilst I am setting the depth and the result is a bit well off centre in the guide bushing.

My question is, does this matter?

My answer would be "Yes, it does matter," because the whole point of bushes and jigs is that they rely on repeatable positioning, which - in turn - relies on the centering of the cutter.

I'm not familiar with that router, but how does altering the depth affect concentricity, do you know?

Ray

Here is a very rough picture of what happens when the bit is not centred, it is exaggerated a bit.




It can be fixed with a bit of planing but it's better to try and get the bit centred.

I was re-reading the leigh book for their D4 and it says
"Ideally, the router collet (and bit) should be concentric (centred) to the guidebush as in figure 7-5. Regrettably, this is often not the case; the bit can be off centre (eccentric to) the guidebush. The illustration shows the problem highly exaggerated. The good news: bit to bush alignment doesn’t affect joint fit or flushness; both are "adjusted out" in normal jig setup."

Leigh D4R Manual Chapter 7 Pg 18

Cruzi they say that what you drew only happens if I use two router with one being off centre.
"Concentricity problems can only arise if two routers are used for through dovetails, (one for pins; one for tails). Routers with different bit to guidebush offsets  (misalignment shown highly exaggerated)… "

Sorry Ray, I didn't answer your question.
The 360b is a fixed base router.
I centre the dovetail bit by adjusting the base to where it is in contact with the guide edges. But when I adjust the depth on the fixed based router it doesn't slide evenly down to the correct depth. This means that what was in the middle is off centre by the time it is at the correct depth.
I hope this makes sense.

Chris

Yes, Chris, it does make sense - your explanation, that is, not the design of the router!

The one thing you can be sure of with the Leigh is that it won't be due to the jig.

Ray

Originally Posted by JackD

Hi Haggismuncher,
Once you do use the spiral bit you'll be amazed at the results as I was, its sooooo easy and smoooooooooooth
Rgards
Jack

Jack was this just for box joints or did you buy the 8mm for dovetails as well?
I am trying to get my head around converting inches and mm, all I want is a spiral that will do the job of a straight cutter (I mostly am working with 20mm/ 3/4" using a 7/16 Guide bush) for the pins.

Chris

Originally Posted by haggismuncher

Jack was this just for box joints or did you buy the 8mm for dovetails as well?
I am trying to get my head around converting inches and mm, all I want is a spiral that will do the job of a straight cutter (I mostly am working with 20mm/ 3/4" using a 7/16 Guide bush) for the pins.

Chris

Hi Chris,
Just bought the straight cut for finger joints from Carba-Tec (very helpful),as per Cruzi's advice. The results are 100% to what I was getting b4 (see pics), I believe that I got to learn to crawl b4 I can walk and run. As far as the metric Vs imperial there are a lot of coverion tables or even cheap calculators that do that for you, yeh its a bummer that we use metric but adopted the american router/tool measurements.
Keep on asking questions and you'll get your answers.
Good Luck
Jack

I'm wondering if other Leigh jig owners would like to have the designs of the furniture’s that is shown the in Leigh advertisement.

and when you ask Leigh there answers is that it is not according to their politic, my opinion is that if a producer really make an advanced jig they as they claim, they should same time offer some designs that the users can follow, even we have to pay extra for these designs, and work instructions.

I suppose that the users have bought that rather expensive tool, so they should be able to do something similar to the advertisement, whit out using neither huge amount of time, or wood.

br

elevalther