Grooving router bit.

I might be interested as i've just glued up a core and I need to groove it.
I've been thinking about copying the jigs posted in another topic ever since I saw them.
How much is postage? I live in England.

Actually i've just noticed that the I dimension is to small for what I want. I realise that you could of course adjust the height of the cutter to accomodate wider surfaces but ideally i'd like the cutter to be longer.
Are they available in 45mm?

will have a look, but as the horn, core i use is usually about 34mm or 1 3/8" i have no problem i will ask if they have a different size. But for wider cores etc if you have a jig set up it would not be too difficult to make 2 passes, better than scraping away gor hours only to find the grooves dont match. Postage in UK would be about ?1.20 in jiffy bag. First class.

Are these router bits off the shelf or did you find someone to custom make them? I had a company in California make me a custom carbide router bit but the cost was significantly higher at $325. As for the height I went with 40mm which covers the bows I have tried so far.

You will have to report back on how well the horn took to the router bit. On the last bow I ruined a pair of horn strips as the router bit was set slightly too deep and so in-addition to milling the grooves it was also thinning the horn thickness. There was thickness to spare but with removing so much material in one pass the horn chipped out real bad. For next time I plan on experimenting with first milling a shallow pass and then coming back for the full depth, my other thought is to finish the grooving by hand.

As for the core I have always had great luck, just keep the material moving in one continuous path with out stopping to prevent any hot spots.

Off the shelf from Germany, you can build a jig to set cutting depth to 1mm quite easily. I find if you glue horn to piece of backing wood nice and flat then use fence as per normal . Groove the core before bending aswell would make things easier.

Here is the jig that I use, I simply move the jig in or out to set the router depth and then clamp it down real good. I typically run a few test samples through until I get everything set just right, for me I have found the re-checking is a good idea as well.

[external image]

That looks really good idea, might borrow that idea if i can. It looks as if the jig having such a small face to present to workpiece would facilitate curved surfaces better. I will have to do 2 passes if width of horn/core is too wide but raising cutter 6mm to line up should not pose any problems on such a shallow cut as long as the teeth line up with grooves.