Incra ibox & British table saws

[Steve Wardley]

Some time ago I purchased the Incra ibox finger joint jig but have not had a chance yet to use it and the main reasons are twofold, firstly the rail that slides in the table saw mitre track is too big for most if not all British/European slots and this means having to make a smaller rail perhaps out of acetal or something of that nature, secondly because British table saws are in the main not able to take stacked dado blades (and yes I know there are exceptions) it means that all your finger joints are likely to be the width of the largest kerf saw blade that will fit the saw arbour, probably around 2-3 mm.
This means the other alternative is to use it with a router table and there again my shop bought router table has slots too small for the rail so now I'm going to have to build a new bespoke router table with Incra mitre slots to be able to use the ibox.
I wonder if any others had come across these hurdles and how you have overcome them, I clearly should have done more research into the ibox but I read good reviews on the product so I probably would have still purchased one.

Your views are welcomed.

 

[Trevanion]

How large are you looking to make the finger joints? You can get 180mm diameter 6mm flat top grooving blades from CMT: https://www.scosarg.com/cmt-240-grooving-sawblade-d-180-d-30-b-6-z-18

Swedex also do grooving blades but they aren't cheap: www.swedex-shop.co.uk/index.php?route=product/search&filter_name=groover&page=2

What saw have you got and how are the blades mounted in your saw?

 

[Peter Sefton]

Steve

I have just cut a load of 6mm UHMWPE strips 17 and 20mm wide for this very purpose, it's a regular issue with European machines as all the American kit is made for standard 3/4" x 3/8" mitre slots. Dado saws are still fairly rare in the UK.

Cheers Peter

 

[Sideways]

Measure your mitre slot.
Buy a length of ground flat stock to fit and replace the original american one with something that will last you out.
https://www.rennietool.co.uk/collection ... flat-stock for example
Cheers

 

[Steve Wardley]

Sideways, Peter, Trevanion.
Thanks very much for your replies, A friend of mine has given me some acetal sheet which I can use to make a new bar as per Peters suggestion and will be good for my crosscut sled which is in the planning. Subject to measurements I think I will also go for the ground metal bar as well, I can drill and tap that as per the original guide bar.
I'm still going to be limited to the kerf size of whatever saw blade I can get hold of and I guess there will be no 10mm joints unless I use a router bit but hey ho.

Cheers again guys.

 

[Trevanion]

If your saw is more than 2HP you could possibly use one of these adjustable groovers instead of a dado stack. Far less faffing around with multiple blades and loads of shims and a saw could be made to fit one quite easily. Or you could buy a fixed 10mm cutterhead. The reason you don't see trenching blade sets anymore is because they've been superseded by superior adjustable groovers.

 

[Noel]

Putting aside your Incra jig you are not limited to joint size by the kerf of a single blade. As long as you have some kind of indexing system, (mostly all built on a mitre gauge type of jig where the joint is made by multiple cuts) you can have as wide a joint as you want. Tonnes of material on Youtube from the basic to the over complicated.

[youtube]6rcOtZ4aa-M[/youtube]

 

[Wilfage]

I had a similar problem with my Charnwood table saw and it's mitre slots. I ended up taking the cast iron top to an engineering firm that milled them out to 19mm for me. Cost about £100. I lost the "T” at the bottom of the slot but at least my mitre gauge and other table saw attachments work now. Small price to pay I thought.

 

[Lonsdale73]

This means the other alternative is to use it with a router table and there again my shop bought router table has slots too small for the rail so now I'm going to have to build a new bespoke router table with Incra mitre slots to be able to use the ibox.

If your shop bought router table is of the mdf type with mitre slots screwed in, could you remove these, rout the slots to accept a 'standard' mitre track, e,g one of Incra's which will accept the slider on an iBox. I had the same problem with my Charnwood saw but no such problem with the shop bought router table.