Finger joints

[silentC]

I've got a heap of offcuts of MDF door jamb material. I was thinking of buying one of those finger joint router bit cutters to see how it would go joining the stuff end to end for some jambs I need in my shed. Has anyone tried this with MDF? What do you think?

[bennylaird]

Haven't tried it but should work ok. The fingers should be stonger than dovetailing it which I tend to do rather than use my finger joiner. (Gifkins is easier to use than the Triton FJ.) the layers in the mdf should give a good hold and would swell a bit with the glue to grip well. Just guessing though.

[Gumby]

I tried using mdf when i first got my Gifkins. I found mdf too 'furry' to get it right and if the joint was tight, you only get one go at it. You can't pull it apart again without getting the mdf all flakey. I'd say finger joints would be the same so if you are going to do it, don't make them too tight. (Not to mention what mdf does to a sharp router bit) :(

[silentC]

Ah, I think you're talking about what the yanks call a box joint. I'm talking about the little pointy fingers. If you have a look at pine fascia board, it's usually made up of shorts which have been finger jointed. It looks like a zig zag in profile. Same principle though.

[silentC]

The bit I'm looking at is second one down on this page:

http://www.timbecon.com.au/products/torquata-jointing-bits-435_1.aspx

[silentC]

I found mdf too 'furry' to get it right
The 'furry' bit is what I'm concerned about. I don't want to spend a hundred bucks on the thing and find out that MDF is just unsuitable for this type of joinery.

[Gumby]

Ah, I think you're talking about what the yanks call a box joint. I'm talking about the little pointy fingers. If you have a look at pine fascia board, it's usually made up of shorts which have been finger jointed. It looks like a zig zag in profile. Same principle though.

You're right, I'm showing my Triton upbringing again. :D I still think that trying to cut MDF with any accuracy is tough. Maybe even worse with those 'little pointy fingers'. But at least you aren't pressing them together in a test fit like you have to in a box joint.

[bennylaird]

Me too Triton fingers.

I think you should try it so you can tell us not to worry when it doesn't work:D :D :D

I hate the spilts that appear any time you try a screwed butt joint. just looks tacky. Pre drilling doesn't seem to help much or might just be me.

[silentC]

One of the problems with MDF is that as soon as it gets thin, it starts to act like cardboard. Scribing it for skirting corners is real fun. The more I think about it, the less feasible it seems. It's just that I have a heap of offcuts and I think it's going to be marginally more expensive to buy three door jambs than it would be to buy the cutter, which I could use for other stuff later.

[bennylaird]

You have answered your own question. Get the bit as it's another tool in the collection. If it doesn't work then buy some new door jambs and have fun with other uses for the bit.:D :D :D

[silentC]

Yes, I'd thought of that. Trouble is that my justification for buying the bit is that it will save us over the cost of buying the door jambs. So if I buy it and it doesn't work, severe loss of kudos and brownie points will result. You understand my predicament ;)

[bennylaird]

Yes, I'd thought of that. Trouble is that my justification for buying the bit is that it will save us over the cost of buying the door jambs. So if I buy it and it doesn't work, severe loss of kudos and brownie points will result. You understand my predicament ;)


But you will have a new toy still:D :D :D :D

Works well for me but SWMBO is beginning to use it agaisnt me these days:( :( :D

[bitingmidge]

Well I don't understand your predicament at all.

"Yes dear, I saved the costs of the jambs, but I still had to buy the architraves and stops....."

I've never had any trouble machining MDF, "MEDIUM density fibreboard" the other stuff which goes all cardboardy could be a problem though.

Why not just do a 45° scarf joint with normal glue? You'll have the same visible join line, almost invisible if you get it right. I can't see that the finger joint will provide too much advantage in that situation, particulary if your framing is reasonably accurate.

Cheers,

P

[silentC]

The finger joint allows you to join up lots of short bits into a single length, which can then be treated like a single solid board. Do you reckon that would work with a scarf joint? I've only ever done them in situ. I suppose if the glue was strong enough. Is this what you're suggesting? I wouldn't like to try and assemble a door jamb in situ out of little bits. My framing is, err, OK, considering. I mean it's hard to get good framing timber and it's only a shed. :o

[Gumby]

I highly commend you on your recycling thoughts here Silent, but in my house, the offcuts would be in the bin. It wouldn't be worth the effort and I could spend the saved time on a more worthwhile project like playing Golf or watching the cricket. :D

[bitingmidge]

The finger joint allows you to join up lots of short bits into a single length, which can then be treated like a single solid board. Do you reckon that would work with a scarf joint? I've only ever done them in situ. I suppose if the glue was strong enough. Is this what you're suggesting? I wouldn't like to try and assemble a door jamb in situ out of little bits. My framing is, err, OK, considering. I mean it's hard to get good framing timber and it's only a shed. :o

Yep, but it WAS a stupid suggestion. The Gumbles is spot on of course.

If you have to buy some more material why not get something really flash, after all it is only a shed.

P

[silentC]

See, you try to do your bit for the environment but circumstances conspire against you.

I mentioned in a recent thread that I had picked up an old bike frame and was fixing it up for my son. I went to the bike shop to get some new bearings for the back wheel. The proprietor rolled his eyes at me and said "leave it with me, I'll see what I can do". I called back a week later and he had no bearings, but instead gave me a 16" bike, intact and ready to go.

So now what do I do with the old frame? Do I try to find a new back wheel, or do I just join the rat race and chuck it out?

[Gumby]

Do I try to find a new back wheel, or do I just join the rat race and chuck it out?

Pass the cheese please. :D

[duckman]

Yes, I'd thought of that. Trouble is that my justification for buying the bit is that it will save us over the cost of buying the door jambs. So if I buy it and it doesn't work, severe loss of kudos and brownie points will result. You understand my predicament ;)

SilentC,

MDF jamb sets will set you back less than $20.00 per set provided you don't buy them from Bunnings. On that basis alone, I recommend against finger jointer MDF to make your own door jambs. If you did make them, you'd still have to buy door stop. Archs you'll have to buy regardless, but I'm sure you knew that.:cool:

FWIW, finger jointing of real timber, hardwood and meranti, for use as door jambs was extremely common, at least it was here in Victoria before the MDF scourge hit big time. A veneer was placed on the face of the jambs so if you hadn't seen the jamb prior to the fixing of archs, you wouldn't know the jambs had been finger jointed.

I never encountered any problems with the strength of the joints. I wish we still had them because I hate working with MDF fixing material with a passion.:mad:

Cheers,

Mark.

[bitingmidge]

So now what do I do with the old frame? Do I try to find a new back wheel, or do I just join the rat race and chuck it out?

Don't DARE throw it out! :eek: :eek:
Here are some options:-
http://www.atomiczombie.com/product-spincycle.htm

http://www.unicycling.org/

http://www.atomiczombie.com/index.htm

Cheers,

P (cheese is for people who don't have birthdays! :) )

[silentC]

MDF jamb sets will set you back less than $20.00 per set provided you don't buy them from Bunnings.
Oh, to have Bunnings as a choice! Actually, I do but it's 200km away and they would charge me $15 to bring them down. From memory, the best price they could give me was $36 a set. My only other option locally is Mitre 10 and they want up around $40 a set.

I've got heaps of arch left over and plenty of stuff to mill more from, so no problems there. I can mill a bit of anything down to make the stops. One of the doors is actually a pair of 700 doors, so I would need to buy the stuff in lengths for that one - more waste. I think it's 4.5, which is useless for door jambs of any size really. You get two stiles and an offcut that's no good for anything. You'd think they would make it 5.1 or something.

Plus, if I buy something, I'll probably get meranti because I hate MDF too - but if I don't have to pay for it, it's hard to resist.

[duckman]

Oh, to have Bunnings as a choice! Actually, I do but it's 200km away and they would charge me $15 to bring them down. From memory, the best price they could give me was $36 a set. My only other option locally is Mitre 10 and they want up around $40 a set.
Ouch and double ouch! You are in a bad way if you're yearning to have a big green shed nearby. You have my sympathy.


I've got heaps of arc left over and plenty of stuff to mill more from, so no problems there. I can mill a bit of anything down to make the stops. One of the doors is actually a pair of 700 doors, so I would need to buy the stuff in lengths for that one - more waste. I think it's 4.5, which is useless for door jambs of any size really. You get two stiles and an offcut that's no good for anything. You'd think they would make it 5.1 or something.

Plus, if I buy something, I'll probably get meranti because I hate MDF too - but if I don't have to pay for it, it's hard to resist.
Its a pity you don't live near me. I would gladly give some door jambs etc. It would be MDF but if you didn't have to pay for it.:D There's always some stuff left over from jobs. I've stopped bringing it home because I didn't have a use for it.:eek:

Cheers,

Mark.

[silentC]

You are in a bad way if you're yearning to have a big green shed nearby.
Just for example, the architrave/skirting I used in our place was $6/lm from Bunnings. Mitre 10 wanted $11/lm for the same thing. Considering I used about half a kilometer of the stuff, I saved about $2,500 buying it from Bunnings. I try to shop locally, but with that kind of price difference, I'd be nuts.


I've stopped bringing it home because I didn't have a use for it
I kept the offcuts because I thought it might be useful for something. I haven't been proved wrong yet, but my optimism is waning... ;)

[TassieKiwi]

Your local tip/transfer station may have one of those Lions Club recycling areas that you can 'donate' stuff to. That's where the trike that needed a new wheel, old iron-horse masport that needed a new iron horse, etc went.

[silentC]

This one would just go back on the scrap heap where I found it if I take it up there. And they'd want to charge me for it! I should ask for my $5 back :D

I'll probably let it hang around in the shed for a few years. It's not quite aged properly yet, only a couple of weeks of dust and NO cobwebs. I put all the bits in a cardboard box last night and sat it on the Incoming/Outgoing table (does everyone have one of those?) where it can sit until I need the space for something else.

[Harry72]

Cut up the ol pushie and use the tubing somewhere else!