Box Joints

[Dick Smith]

OK - I'm being a bit pathetic here, but I could do with some help.

I want to make a finger-joint jig for my router table (can't do it like Norm as no dado cutters). This, I know, is perfectly feasible, and I have lots of different plans, but my first two attempts have not been successful.

No 1 - 1/2" router bit had a lot of trouble cutting the first slot, when I went for the second one it blew out the space between. I also broke the mitre fence (an old plastic one) by screwing too tightly through it. Retired for a cup of tea and a think.

Bought a 1/4" good quality cutter (Trend) and a new Trend mitre fence. Tried again, but it took a lot of effort to cut the first slot - enough to think that I was straining the equipment (the router in the table is an old 600W Bosch with 1/4" collett). A second slot and then cutting through two pieces of stock looks like it might be a problem.

What should I do next? I'm not going to pop out and buy a 1/2" router just yet (though I might in the future) and my present 1/2" won't work in a table. I would like to go bigger than 1/4" for my joints, as well. Would an MDF fence be better than the softwood I am using?

Help!

[Bugsy]

I don't think there's anyone on here who could help you with that Dick................

[Dick Smith]

I realise that 1/4" router bits might be a bit delicate...

I've just been out and made another jig using MDF, and it works a lot better, although there is still some blow-out. I've made a joint (of sorts) on two bits of old lambris, which might not have been the best of ideas! It works (though it's messy) but it's too tight. What causes that? How do I adjust it out?

Come on Mr Zjob - Steve - you must know how to do this! Let alone the professionals!

[Dave&Olive]

hi  Dick

   ok I made one just like Norm for the router table using MDF . It works perfect ,but even using my big Freud router found it hard to stop the break -out on the second cut ( but did use a 1/2 bit ) so I just cut one at a time. set the box out like you would when cutting dovetails and cut the odds and evens, if you have set it up right at the start it should end up like this

http://s83.photobucket.com/albums/j311/daveolive/?action=view&current=Pdr_10.jpg

 dave

 if you want a photo of the jig Istill have it hanging up here somewhere

[Dick Smith]

Thanks, Dave, that's what I'm looking for. The chest looks great - I will get there one day!

A guy on a woodworking forum aimed me at a site with a lot of tips, and it seems that if the joint is too tight then the jig should be moved a small amount towards the cutter, if too loose, then away. It looks like I was too tight in my measurements when I refixed the jig to the mitre fence.

When I can make a bit of noise tomorrow I'll make Jig Mk IV, which will have bolts and wingnuts to fit it to the mitre fence, running in elongated holes to allow for some adjustment. Norm's is OK if you can get the adjustment right first time, but I'd like to use something that I can fiddle with. If that works, I'll make 3/8 and 1/2 versions.

I'm really only going to use it for small stuff, drawers and so on, and a medicine chest converted to make a small kitchen wall cupboard.

If you are interested, these sites are fascinating:

http://www.wealdentool.com/acatalog/routing_hints_and_tips.html

http://www.routerworkshop.com/boxjoints.html

[Dave&Olive]

hi Dick

  really busy sunday but will take photo of mine and post it for you. I donot use the fence , I use the mitre slot as the guide I screwed a piece of metal into the jig  same size as the slot and use this , doing one at a time if the join is tight just run the joint through a couple of times ,each run although its clamped still seems to take off a few thou more.

if you want will even do it by email

 dave

[Dave&Olive]

sorry forgot to post this site maybe easier to copy this than a box jointer

http://www.dbkeighley.co.uk/masters/wr5.htm

a woodrat

dave

[Dick Smith]

Thanks, Dave.

No rush, I've got two sets of reports to write tomorrow, and Julie has made it clear who is going to do the shopping, so I ought to be staying out of the shed!

I have seen what I think you mean (sort of) advertised in the USA

http://ca.oak-park.com/catalogue.html?list=boxj--&product=SF1030

They say they don't send to the UK, but I can get No2 son to get me a set, I think, and send them over - so that might be a result for less than £30!

Edit - I'd love a Rat, but I'd need to be making money out of wood to justify it, and that's a few years off!

[powerdesal]

Dick,

Iv'e just seen this thread. I am afraid I cant really help, I have never tried jointing like that but am sorely tempted. It would seem that building the jig like Dave has done is a long way towards the answer.

On the point of 'blow out' during second cut: I'm guessing that speed is the critical factor. That plus 'forcing' the work (maybe), it cant be a blunt cutter because you are using a new one. Is your router a multi-speed, can you try test pieces at both lower and higher speeds to compare? I am also guessing that wood grain structure is a major factor also.

My idea would be to waste a lot of test pieces establishing the right speed + feed rate for each individual type of wood. Easy for me to say I know.

I do know that its tempting to feed that bit harder than is needed, Have done it under other circumstances - with disastrous results.

I think Dave is probably the most experienced, judging from the chest he built, unless JJ come on with the answers.

Good luck, keep us informed.

[Chris Head]

Like Steve says, it's just a question of time and practice. Certainly good cutters are the starting point. I'm not a great fan of the finger joint, dovetails are for life and imho are far more attractive, but that's just personal taste

Money spent on a Rat or Leigh (I have a D4) is money well spent, one piece pays for the jig. the cheapo stuff is frustrating.

Happy chopping.

 

[Dick Smith]

I think that the answer to the blowout is better clamping of the work piece to the backing fence.

The timber is also a factor, and I want to get some better stuff, but I am just practicing on bits laying around at the moment.

I can't vary the speed on the router in the table, it's an oldish Bosch that I don't use for freehand stuff since I got my Trend (excellent) and huge great 1/2" lump from Sainsburys, which I don't think I've ever used as the Trend is so good. Perhaps I need one in the table as well.

I agree about the feed rate and possible problems - I unclamped a piece yesterday before the bit had stopped spinning, and it fell onto the cutter - 0 to 1000mph in 1/2 second - fortunately away from me!

I'm going to see if I can get those polyethelyne jigs from the USA. AT $60 for 3 they are good value if they work and not a financial disaster if they don't.

Have a look at the video on this page and tell me what you think.

[powerdesal]

Just watched the video. Impressive. It looked like quite a high speed being used and a fast feed rate. All hand held stuff but the quality of the wood looked extremely good, very close grained.

Are you clamping to a 'traveler' running against your fence? Do you really need to?

[Dick Smith]

Yes, I'm using a modified mitre fence to run along the guide slot.

Yes - excellent wood - but I've no idea of what it is. Norm never uses it, anyway!

In the video I think that the 'film' might have been speeded up - but certainly I want to keep my fingers a bit further away, always a risk with repetitive operations, and 100+ passes is quite possible. I like to count up to 10. So yes, some thought to how the work is fed through will be worthwhile.

They also sell push-pads and sticks which have saw-handle grips on them - which is a nice idea, and I might well copy that. I'm also taken by their router table top for about $80!

[powerdesal]

Who is this Norm I keep reading about.?

[Dick Smith]

Norm Abrams, who has had a woodworking programme on US PBS for about 20 years, called the 'New Yankee Workshop'. He is slightly controversial, especially amongst purists (or wannabee purists).

He has a website here, and you can buy plans for all his projects. One of my next is one of his, a medicine cabinet adapted to be a kitchen spice cupboard. That's what I want the finger-joints for.

[Chris Head]

It seems that the whole thread is about gimmicks and finding an easy way to cut a joint when it's not the joint that is important. What about the piece? That comes first. How will the joints affect the aesthetics of a project that will be around for a long time? It's a bit like learning grammar I guess....I would imagine that shortcuts would become quickly transparent without a solid grounding.

 

[Dick Smith]

Sorry, Chris, I was just looking for some help, but you have to leap in with YOUR priorities and just chuck spite about.

I was enjoying that chat, Steve, but it's over for me now. Must remember - I'm not allowed to post in Chris's section because I don't share his obsessions.

[Chris Head]

That's a shame Dick, I'd dearly love to help you. I'm just trying to take you back to basics. You trod this path knowing that pro's were about. I'd personally happily give up my paid time to move you forward, I know that's what you need. What I do isn't rocket science, what you do is. And drop the aggression, it gets nobody anywhere. I applaud you for asking the question. If you could come and spend a few days with us I'm sure I could blow your mind away and send you on your way with a few new perspectives, perhaps you could tell me all about grammar at the same time?

[Dave&Olive]

hi

 ok pics of jig as promised.

 http://s83.photobucket.com/albums/j311/daveolive/wood-work/

it`s a piece of 3x2 planed square on 2 sides , and a piece of 3/4 " stock wood , glued and screwed. and then the front face planed square again.

now using the mitre fence route a grove for the "metal runner" (you could use any hard wood in place of this ) you need this to be a nice snug fit in the jig and just deep enough so that the jig fits flat on the router bed when fitted. now screw this in place.

now fit the cutter you are going to use to cut the box joints in to your table and cut a grove deeper than the joints i.e. I used a 1/2" cutter and set the depth to 3/4" deep , because you have planed the face square and cut the first grove with the mitre fence this grove will be parallel using your runner.

  now cut a piece of hard wood to fit this slot but make it longer than you  need, because you need a packing piece for the next stage and fit it leaving say 3/4 " sticking out to the front of the jig

 now it gets tricky , remove your metal /wood runner, you need to cut a slot along side this one but the same distance away from it as your cutter diameter . not as hard as you think, use your mitre fence again to hold it square, and the " packing piece " gauge the distance between the piece of hard wood and the router bit ,clamp and cut the second slot .

  now with this done remove the hard wood piece form its slot and glue it into this slot and replace the runner.

you should now have a box joint jig set up for your chosen cutter.

how to use it in one hour, and how to stop break  out with it

  dave

 

 

[Dick Smith]

Thanks, Dave. That's pretty much the design I used, except I bolted the fence to a mitre fence, so that I could adjust it later. That seems to work OK. I think where I went wrong was in cutting the second groove, which was just too tight, and my 'adjustable' fence isn't as adjustable as I planned! That's 2 problems, so no chance!

I drilled a couple of holes with larger clearance holes to take two 1/4" coach bolts, which pass through from the front and I used wingnuts at the back. I had been generous with the hole diameter and I thought that would give me enough adjustment, but I was wrong!

The American system I have seen is very interesting - it is a 6"x16" sheet of plastic (looks like a plastic chopping board) with a small fence set in, they do 1/4", 3/8 and 1/2. They also sell brass dimension rods, so to use it (after setting up) you run the first pass with the work away from the fence, then move it over the fence and so on as in your method. From the video it looks dead easy, but then it always looks dead easy on the video!

I'll have another go - this time I think I'll rout a slot for the coach bolts, so that I get more adjustment, and as Steve suggests, stop messing around with offcuts and try some decent timber.

Thanks for all the time - I like your stuff, that's the sort of thing I want to make and might actually be able to make with a bit of practice!

[Chris Head]

Oh Dick, Dick, Dick, such silly huffy puffy games. My offer is genuine and stands. You and Judy (or is it June?) would have a real ball here with the kids and the animals and the cooking and the banter...and of course the woodwork! I might even let you have a go of a real live, kick ya to death chainsaw...you might even discover a bit of life on the wild side! Dare ya to pick the 'phone up ya huffy gruffy grumpy wumpy hairyone!

[Anton Redman]

I own two things that belonged to my Paternal Grand Father ( My Dad's Dad for those of you who do not have the Latin) One is a mass produced silver watch lacking a chain and the other is a set of planes which will do every thing a cheap router will do but take a lot more skill and effort to use. The watch anybody could have but a friend has the planes.

[Dick Smith]

Anton - I've got some old rebate and routing planes, but they won't do this job as well as a router - and with hundreds of cutouts it would take forever, and therefore stop being FUN.

[Dave&Olive]

ok

 back again

   lets start by cutting your wood over size , why, because the joints always look better when you hit them with a sander after and this will take out any breakout scars on the end of the fingers ,so say on a 1/2" finger allow at least 1/8-3/16 " to sand so make the wood X -2 bigger i.e. 1/4-3/8" and do not forget to cut the joint deeper by this amount.

 I too found out that trying to cut 2 joints at the same time made tight joints so cut one at a time ...how later.. make sure you cut the joint from the outside to the inside and DONOT PULL THE JOINT BACK THROUGH THE CUTTER this will now only give you break out on the inside .

ok lets use the jig... call the sides male and the front and back female. now mark them top and bottom. the males have Dicks at the top the females have slots .so male joint first .. with the outside facing the cutter and the top facing the cutter butt the wood up to the hardwood piece of wood that sticks out from the jig clamp and cut . do not pull back but lift off. now fit this slot over the hardwood and cut the second one and so on ... now the other side.... you will find out this now will not work .... keep the top to the right i.e facing the cutter but the inside faces the cutter .. drop in at the back a piece of thin ply to stop the breakout and carry on.

the female ends same thing outside facing cutter top to the cutter but place that bit of extra gauging hardwood you cut from part one between the hardwood piece and the end to give a gap clamp remove the gauging wood clamp and cut ...repeat as for sides.

if your joints are too tight you can cut them again , but first use a piece of paper  as a packing piece to increase the gap between the top and the hard wood finger on the jig . this will make both the finger that much smaller and the slot that much bigger so do a test piece first.

using this method to make the joint bigger you only do it on the first cut , then but the next one hard to the right to make them all the same.

sorry I am no teacher but if you don't follow it .get back and will try more( sounds a bit like my school report...needs to.....)

  Dave

[Dick Smith]

I see what you mean, the order of cutting is obviously important. I expect I'll learn that by trial and error in the end.

With mine the fingers lined up well at the beginning of the cuts (the first ones), but by the end they were 1/16 out, which is no use, of course. I want to be able to adjust my fence instead of shimming, but if you are talking the thickness of a sheet of paper, that's a fine adjustment!

Many thanks for your time, Dave, and for understanding what I am trying to do. If I manage it I'll send you the photos! Cheers, I owe you one.