Long Dovetail Cutter? (Router)

[OPJ]

Last week at college, I got stuck in to a lovely little jewelry box (Christmas Present) made from really nice sycamore until I hit a brick wall - the dovetail cutters we have at college are too short.

I went to the effort of making an accurate jig from 12mm and 18mm MDF to rout dovetailed slots in each corner to take dovetailed splines in a contrasting timber (probably walnut).

The cutters we have at college are too short. I'm looking for something ideally 5/16" (8mm) in diameter although 3/8" (9.5mm) is the maximum I can go for or else it won't work.

I think Wealden have a 3/8" cutter listed on their site which could be long enough, but I'm wondering if anyone else has any ideas?

T1012

The top of my jig is made from 12mm MDF and the sides of my box are 16mm; which gives you mitres close to 20mm long, I think. My router has a plunge of almost 65mm, I think?

Thanks for your suggestions. Much appreciated.

 

[bjm]

Why not use your jig on the table saw - set the blade to 14 deg (or whatever) to cut the sides and trim it up with a chisel? - no extra cost apart from the scrap to try it out.

Brian

 

[OPJ]

That's a smart idea but, unfortunately, I don't have a table saw - anymore. Also, I don't think my tutor's would approve when I told them how I had to remove both the guard and riving knife from a machine when I could have probably cut them by hand! :wink:

 

[Adam]

But some from Woodrat. They have longer cutters.

Adam

 

[bjm]

Short of trying to get your tutors to invest in a collet extension it looks like you will be honing your hand tool skills! You could also modify your jig a little to enable you to rough out most of the cut on a bandsaw?

Brian

 

[Steve Maskery]

This runs parallel with Wizer's post on drawers.

You can cut DT's very accurately on a bandsaw with a couple of jigs. Mark Duginski's book has the details, although there is a typo which makes quite a difference! The test says WITH spacers and the photo caption says WITHOUT spacers! The text is the correct one IIRC.

If you have a Good Woodworking archive, I wrote up my version of this technique, with a couple of extra jigs to make it safer, in GW174.

HTH
Steve

 

[woodbloke]

...or you could cut the dovetails completely by hand and not need to use a machine cutter at all
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:arrow: .....coffee, then workshop - Rob

 

[OPJ]

Thanks for all the replies.

I'll have a look at the Woodrat site, Adam, as this seems the most likely way I am going to go with this now. I'll have to finish the box off at home/in my own time because they want use to focus on dovetailing for the coming weeks - through, lapped and even secret mitred ones! :shock: :wink:

Woodrat don't seem to specify an overall length for their cutters though?

Steve, I do remember one of your excellent articles on dovetailing with the bandsaw and appreciate the though, but right now, with Christmas fast approaching, I'm looking for a quick result. Thanks anyways though.

Rob, hand-cutting those joints would certainly fit in with what we're doing right now, but I'm not yet up to a satisfactory level to compensate for the fact I already had a very accurate MDF jig awaiting router and cutter.

 

[woodbloke]

OPJ wrote:

secret mitred ones!

Olly - if you have a look at the Teak Casket in the Competition you'll see how I cut them, not too bad but you need to be super accurate in the marking out and cutting. There'll be an article(s) on its construction in the latest edition of F&C due out shortly.
The only way to get yourself to a satisfactory level and be confident to cut these sort of joints is to practice them... and then again and again, you will after a while produce good joints and wondered why you ever contemplated making them with a jig - Rob

 

[andy king]

Hi Olly,

the one you picked is for a Leigh jig, so should be fine as they have over long shanks.
this one: http://www.diytools.co.uk/diy/Main/...5&iBrandID=0&iPriceRangeID=0&iProductID=65865
is by Trend and is 7.9mm and there's a 6.3mm if you want narrower still.
Bit pricey at £19.50, but it gives you the option if you want the size.

Andy

 

[andy king]

Better again is this if it's for a one off. http://www.axminster.co.uk/product....perform+dovetail&user_search=1&sfile=1&jump=0 less than a fiver!

Andy

 

[OPJ]

Thanks Andy, the Perform one looks very tempting as this will probably be the only one I make for the foreseeable future - but I've gone to the effort of making this MDF jig, so I'm also gonna look at this purchase as a long term investment. I also already own a set of decent dovetail cutters which I've yet to use.

I'm now thinking about collet extensions for my router (CMT ones from Axminster seem to be the best price around).

Are they really worth the money? I've also noticed you can buy 1/4" and 1/2" sizes. Would I have to buy sizes for each shank diameter of cutter, or would I be able to insert a 1/4" collet in to a 1/2" extender?

 

[andy king]

Hi Olly,


Collet extenders are designed for table use rather than hand held, and while the CMT ones are great quality, the best on the market in my opinion has to be the Xtreme Xtension sold by Woodworkers Workshop

http://www.woodworkersworkshop.co.uk
The overall length of the collet extension is less than the CMT, but you tend to find you aren't looking to gain a huge amount of increased length, simply overcome the thickness of any router plate and a tad more if needed.
The CMT types need a pair of spanners to lock the cutters, and with the extended length, can have some degree of 'whip' in them if used with big bits such as panel raisers.
The stubby profile of the XXtension makes it far more stable under load, but it can need a bit of trial and error when initially setting it up to ensure concentricity.
Best of all is it needs a simple hex wrench to swap cutters, and a quarter of a turn is enough to slacken or tighten when doing so, and takes only seconds to achieve.
Worth paying extra for the sheer ease of use if you intend to use a table mounted router regularly.

Hope this helps.

Andy

EDIT: Also sold by Rutlands here: http://www.rutlands.co.uk/cgi-bin/psPro ... i/XTENSION

 

[OPJ]

Thanks again Andy - now that you mention it, I do remember you getting excited about the Xtreme Xtension in Good Woodworking last year! :wink:

£50 isn't a lot of money, I reckon. Trend's own are about £50 each. It seems the XX only gives an extra 1-1/4" depth where as the Trend one has 50mm, but surely that's plenty for anything I'm gonna do!


Rob, thanks again for the tip on dovetailing. I'm getting on really well with the practice dovetails we've been doing at college, although I must admit I'm looking forward to a short break at Christmas! :wink: My through dovetails are coming out very well, even though my first attempt at the lap dovetail was... AWFUL! So bad, you could almost (almost!) pull the joint apart! The next one was much better!

I've found already that I do a really nice job accurately marking and cutting the pins - I'm confident enough to cut to the lines - but when I come to the tails, I find it better to leave more on from my marked lines, otherwise they become too small?

Don't know if you've come across similar problems? My 2H pencil is always and I try to mark tight against the pins, right in to the corners.

Nice to see your work in F&C, by the way.

 

[andy king]

Well Olly, living in sunny Pill, just down the road from you, you'll understand that we don't often get much chance to get excited about anything! :wink: :lol:

Andy

 

[woodbloke]

OPJ wrote -

I've found already that I do a really nice job accurately marking and cutting the pins - I'm confident enough to cut to the lines - but when I come to the tails, I find it better to leave more on from my marked lines, otherwise they become too small?

Don't know if you've come across similar problems? My 2H pencil is always and I try to mark tight against the pins, right in to the corners.

Olly - don't know if you've seen it, but there is a really excellent piece on cutting lap dovetails in last months F&C (Issue 134) by Robert Ingham...well worth getting hold of and absorbing...glad you liked the article in the current issue :wink: - Rob

 

[OPJ]

Thanks again Rob. Yes, I've been a subscriber to F&C for a few months now and I do indeed have the issue with that article in my collection. Normally, I'd glance through an article on dovetailing - but it isn't until you've actually tried something that you want to go back and read some more, I find. It's been the same with woodturning, for me.

I've also got Robert Ingham's new book on my Christmas List! :wink: