Dominos as "splines" in mitres

[Flowboy]

Hi everyone,

I have been playing with the idea of using dominos, or the mortise at least, as a sort of invisible spline system for box construction in thin stock (e.g. 10-12mm.) the pics below show 5x30ml dominos used in 20mm deep Taswegian Oak cut at 45 degrees. Basically, it works. There are some caveats though, which I can discuss in reponse to questions rather than blather away here. One though, is the issue of depth of cut, but I think the get around is to overlap the bevel on one piece with the top of the pice to be cut. This will allow safe anchoring of the workpieces, while forcing the cutter to be held up during the cut.

Regards,

Rob

[Flowboy]

Hi all,

Me, three camels laden with supplies and water enough for the return journey made the overland treck from Heidelberg to Carbitool in Moorabin east, in their really swish new facility.:eek: :D
Unfortunately, they are not interested in producing cutters like those used in the Domino, but could outsource to "a company in Italy" (CMT). Also didn't like the idea of producing small bits either.
Also, by coincidence, ran into the Festool Rep. I think he wishes I hadn't, but he did tell me they are looking at longer cutters and a bench mounting system for the Domi (shades of the Triton biscuit joiner option:confused: ). Anyway, they do not have the bits we wanted and don't have them anywhere else in the world. Unless TT are prepared to look at this (and I really, really doubt it) we'll have to find another solution.

Regards,

Rob

[Lignum]

Hi all,

Also, by coincidence, ran into the Festool Rep. I think he wishes I hadn't, but he did tell me they are looking at longer cutters and a bench mounting system for the Domi (shades of the Triton biscuit joiner option:confused: ).

Thanx for your effort in trying:D And what is the "bench mounting system for domi" ?? did he give you a clue ?? Or Anthony if you are reading this do you know:confused:

[patr]

Rob
Many thanks for trying but the answers you got are much the same as those given to me after approaching several manufacturers and small machine shops. Economy of scale was one answer and the 'lateral forces on smaller bits would break them' was the other. I would have a go my self on my Toyo lathe but do not want to bugger up the Festool warranty. My Festool dealer in Germany was of the opinion that if it were an option, Herr Festool would have made them and considered that the 5mm cutter is probably the smallest possible whilst retaining sufficient strength to do the Domi action. Keep on trying though.

regards
Pat

[Auld Bassoon]

My Festool dealer in Germany was of the opinion that if it were an option, Herr Festool would have made them and considered that the 5mm cutter is probably the smallest possible whilst retaining sufficient strength to do the Domi action. Keep on trying though.
Pat

G'day Pat

Firstly, thanks to Rob for trying http://www.woodworkforums.ubeaut.com.au/images/icons/icon14.gif but I too have my doubts about a cutter smaller than 5mm being strong enough to withstand the oscillation and the turning moment, unless the oscillationatory (is that a word?)motion could be converted into a series of direct plunges - but then that's what a router does so well.

In any case, as with Pat, I'd be very averse to doing anything that might compromise Herr Festool's warranty terms :eek:

PS I trust that Simou is getting used to the taste of Euorpean Beech biscuits :)

[Flowboy]

Hi all,

Lignum, He didn't expand, but for a rep in the field to be mentioning it, it can only be a matter of months rather than years away. I didn't ask anymore, sorry.

Pat, You can only try. The danger of destroying the Domi is a major concern, but I was hoping that lateral cutting, where the cutter does the moving rather than using a router, where the timber pushes hard against the vertical axis of the bit, may have a beneficial effect. The bottom line is, as you say, no-one wants to produce very thin bits as they invariably come back to bite them, so to speak. (Ask Simou, he'll understand.)

Must keep thinking, though, there must be a way. I even thought of using very small cutter lengths, so that the actual cutter as part of the bit, would be proprtionately thicker. These do not have to be particularly long, nor do they necessarily need to be spiral bits.

Just to finish, we're asking the Domino to do things that are feasable, but not within its speced functionality. So stopping production at 5mm bits is what they started with because its what there research told them we need. The fact that they recognise the other issues such as the need for deeper tenons and bench top fixture for ease on long panels, shows that the product is developing and (dare I say it) there seems to be some interest in what the customer needs. Lignum I really think we need to make TT aware of what Australia is doing.
And, are we sure this company is German:confused:

Regards,

Rob

[patr]

Steve


PS I trust that Simou is getting used to the taste of Euorpean Beech biscuits

This house is a now biscuit free zone. Biscuits given to Son1 and the chap who bought the Lamello (which, bless it, sold for more than I paid for it 3 years ago.)

Rob

Is TT the infamous Tool Technic? Same as here in YUK, a wholly owned part of Festool. If so then German efficiency seems to vaporise just about a metre over the German Border on its way to Oz as well as to this Land of Song!

Regards

Pat and, were he not giving my poor Postman a hard time as I type, the fearless and biscuitless Simou.

[Flowboy]

Hi all,

Just some destruction photos of a Burmese Padauk (aka Burmese Rosewood) box being made using 6mm dominos as splines. I used the Domi to cut the rebate in the lid as well.

Regards,

Rob

[Powertoolman]

Rob,
I am curious why you want to use a spline joint (shown in your pictures) instead of the standard floating tenon of the Domino? When I first saw this I thought it was an innovative use of the Domino tenons, but the more I think about it, the more I am puzzled. Is there some benefit with this joint that I am overlooking?

Because you used the larger Dominos, obviously strength should not be a problem, but normally I would think that a tenonned miter joint would be stronger than a splined miter joint. The subtle difference being the grain orientation of the spline or tenon.

Most people don’t think about it, but the difference between a biscuit joiner and Domino is that a biscuit is a spline; not a floating tenon. The grain orientation of a biscuit is not parallel to a spline, but it is close. A tenon has the grain perpendicular to the joint.

Did you do this so you could use the larger Dominos without having to cut them to length. That would make sense. Or was there another reason?

Rick

[Flowboy]

Hi PTM,

First, thanks for the info on the TS55. Using Polystyrene would give the same result as what I described, but would be wasteful I think and just another thing to carry round.
With regards to the box construction, given there is a reduction in strength across the joint, my aim, as is not demonstrated here, was to provide a more substantial means of jointing in constructions where there is insufficient stock to be able to cut the 12mm min. depth the cutter requires. As you correctly state. Biscuits obviously could be used, but
a. I don't have a portable biscuit cutter and
b. Getting a box together is awkward at the best of times and having stable tight fitting (so they just slot right in) dowels is a way, to me, of making it easier.
Ultimately, I did it to see what if.. and because I could.

Regards

Rob

[Flowboy]

Hi PTM,
Couple of things I forgot.
I like the precision of the domino when cutting in "confined spaces". You can cut a 5mm mortise in 10mm timber fast and accurate and to a length of your own choosing. You can even use 3x5mm dowels in a 20mm tall structure.
This was my first box done this way. It would be possible to cut splines across the grain and improve the strength of the join, sort of like a giant tenon:confused: .
The one aspect I have t sort out in small boxes is the angle and/or depth of cut. It is possible to put an artificial facia across the front of the cutter, but everytime you add to this you move the cutter further down the face of the mitre.
It may be that this is an innovative use of the domino system, but it may prove to be easier to buid a 45 degree jig and run them all through this.
Hopefully, the former.:)

Regards,

Rob

[Powertoolman]

Rob,
No, I was not suggesting you should use a biscuit joiner for your miters. My biscuit joiner will be up for sale cheap shortly, (dust and spider webs included). I was merely inquiring as to the reason behind your method. I still have some questions, but I don’t want you to think that I am criticizing what you have done. I was just curious about it.


I am new here, so I hope you did not misunderstand the meaning behind my questions.

[Lignum]

Rob,
My biscuit joiner will be up for sale cheap shortly, (dust and spider webs included). .

Good to see:D Wont be long before their will be so many second hand bic joiners on the market they will be a dime a dozen. And i see where you are coming from with the splines as i was thinking the same thing. A normal floating tenon will move with the forces as opposed to a spline that will fight it. But the one thing PTM that you will soon be aware of is Domi is so good you just want to experiment with so many different joins and uses just like FlowboyRob:D Gotta love the Domi:D

[Flowboy]

Hi PTM,
No problem this end, you're just wanting clarification of issues. As Lignum said, we all experiment with this, sometimes it works, sometimes... Just like the real world I guess. Please ask away. If I can't answer, Lignum, Rocker, Auld Bison (sorry, Bassoon) and PatR, amongst the many others, will certainly be able to. I was thinking out loud with reference to the BJ, trying to think of alternatives I have available.

Regards,

Rob

[Lignum]

sometimes it works, sometimes...

But their still would be times when your way would work. If the thickness wasnt enough to have a deep enough tenon then a shallow one with spline would be good. The less timber the less movement, so alternating grain in the real world wouldnt be a problem :D

[Flowboy]

Hi all,

I have the answer, for me at least.:confused: :eek: :)

The heart of the problem was how to strengthen a 45 degree mitre joint in narrow stock without the need to construct jigs for routers (due to the narrow nature of the timber and accompanying safety concerns) or use hand tools (at which I am not overly adept and which take a lot of time for creating the desired joint.)
The Domino provides excellent accuracy in Mortise cutting, even in areas where very little stock will be left above and below the mortise, so is ideal fr this purpose.

My FMT (Frame Mortise tenon) jig can produce tenons in any length, width and depth I want, so I can generate sufficient tenon stock for the project probably in one pass, then cut to size on the Band Saw. Full floating M&T joint, still in very fast time and no messy biscuits falling everywhere!!
Think I've got a handle on the depth of cut reucer as well.

I shall document and publish this project forthwith!

See PTM, you try, you refine, you succeed. Such is the power and consistency of the Domino in these situations.:D :D :D :)