tell him to do his shirt up before he does himself a mischief in a power tool!
Green Timber structures- Any experts in the house?
Good point. Crazy kids...
I'm not so keen on the half lap joint. I'm sure it will support the weight, but it wont prevent the parts separating as well as a mortise & tenon. Needs must I suppose.
In my ignorance I have used pieces of brush handle to make dowels before. They are seasoned, the right size, have a long straight grain and are readily available. I didn’t have any oak either.
Great project. Love following the thought process.
I hope the tentacle end can take the weight of a person, because I know my boys would want to run straight down it!
I share your thoughts on the half lap really beaker2135. I think the problem is we are not really set up to cut these joints as well as we'd like, we are finding our cabinet making tools a bit limiting.
I borrowed a small electric chainsaw which has made some aspects easier.
We took the elements of what slackalice was saying about resisting the cantilever forces but simplified it.
To address the potential for the joint coming apart, we have added extra pegs at all different angles, thinking this would create some sort of mechanical lock of sorts. Hopefully we're right.
Detail of angled pegs
View of side of one joint
A few tentacles starting to come together
You can just about see here the mitred shoulder we have kept on the halving to resist the cantilever.
I know nothing about wood, but am loving this thread can't wait to see the finished product..
Hey Kayak, those joints are looking very tidy. I'm not convince about the angled pegs though, sorry. I see your thinking with the half-lap scarf's, however, you're asking the pegs to do a lot in terms of both longitudinal and lateral strength - if you get my drift? The tenon would take care of resisting the lateral movement, leaving the pegs to work solely on resisting longitudinal separation.
May I ask? Do you have a skill saw / circular saw? The joints I detailed would be much easier to cut with one. Preferably a 9" saw that will give you a 75mm depth of cut, so by turning the tenon stock by 180 degrees, the tenons can be fleshed out in very short time, 1st cut set at 50mm for one side of 45 deg shoulder, turn stock over 90 deg and with max depth, rip cut full length of tenon on both sides of cheeks. Turn stock 90 deg and reset to 50mm for the other shoulder cut and then turn again with max cut along cheeks. Finish cheek cuts with hand saw and job done.
The mortice joint could be done in the same way, except with a series of longitudinal cuts and remove the slithers with a broad chisel and then use a chisel to remove the final bit at the end to your scribe line, unless of course if you have access to a chain morticer, in which case it will be even quicker as you'll be able to take the flesh out up to the 45 degree shoulder.
I know what you're getting at slackalice. The tenons or in fact any part of the joint on the square stock was not a problem at all.
When you come to the logs however, it is incredibly difficult to take a reference from anything.
Every one is a different size, diameter, length, plus obviously they are all a few metres long.
We found trying to cut two parallel 45 degree shoulders, square to the tenon/mortise and a further one and then marry up all six was....... Not really happening. You can't just invent what is 45 degrees either as there is no reference. You have to try to sight an imaginary line running through the two components and imagine a plane to estimate 45 degrees off.
We then found digging the waste out of the mortise was very hard as our chisels are way too short. We do have a chain mortiser but can't mount the logs on it as they would foul on surrounding machinery. Plus the mortise needs that 45 degree shoulder in it anyway, not vertical.
All in all, for the amount and variation of what we're dealing with, and the time constraints, we thought we might get away with a halving, albeit with 45 degree shoulders. I'll maybe have more of a think about the separation thing but I'm thinking angled pegs will certainly help....... Maybe
Nice updates and I think it will look good once it comes together. I'm not 100% convinced by how the joints will bear up over time, or of the angled pegs value, but know exactly what you mean about sometimes being limited by space, tools and the material and having to get something that works done as best you can with what you have and it looks like a good job with something of a learning curve to it.
It's all progressing well though - it's really a shame you don't have more full lengths to work with (it's not like they are high value so shame they couldn't have offered more) as it would have been a good/fun exercise to work through a series of jointing techniques as a sort of experimental/ "educational" process.
Still looking forward to the next update...
Thinking out loud here....
You know how on big packs of plywood etc and packing of large items you get those tensioned steel bands?
Compromise?..... Could work/help...
kayak - loving this thread - looks great and the idea is unique! I have no help im afraid with regards to joint strength..infact i have a question for your cabinet making skills.. can i be cheeky and ask you some advice?
email should be in profile..
Morning kayak! With irregular shaped beam stock, the datum's or reference's can be determined by snapping a chalk line along the length of the stock on each quadrant. Whilst not exactly 90deg from each other, they will aid your efforts. Alternatively, you can square off the section of stock that will receive the joint and as it looks like its the ash tentacles that are proving difficult to mark out, these are the tenons, so squaring off need only be done to the upper and lower surfaces.
It's much easier to spout forth from here - 100 miles away - so please forgive me if you've already tried the above!
Likewise, trying to explain how to cut the mortice with the chain morticer and still achieve the 45deg angle is easier for me to show, rather than explain in type written words, so sorry for my deficiency there!
I would not use the bands, nice idea however, they kinda take away from the whole natural wood feel that this has and will have. Instead, I think the joints will be fine so long as you stagger them. It's only the top beams that will be really vulnerable, as the lower layers will be supported by the layer above, no? In which case, use the mortise and tenon joints for the three top beams. You also have the spacer battens, so is it possible to use these as some form of structural rigidity? I mentioned in one of my previous posts that these could be 60x60mm and rebated into the beams and located with pegs themselves. It maybe that with some positioning, they can also provide a measure of support after the joints?
I'm loving the look of the tentacles you've fashioned already, the end result will look unique and stunning and I'm really quite envious!!
Have a great day.
You could run some of this through with washers to spread the load and then countersink and put wooden plugs on the surface so they just looked like the pegs.
I would not use the bands, nice idea however, they kinda take away from the whole natural wood feel that this has and will have. Instead, I think the joints will be fine so long as you stagger them
I know what you mean, but actually the student was talking about using some sort of banding here and there as a decorative 'addition'. A bit like a tribal armband sort of thing... Not sure, anyway, if we see that it's a problem then I guess it's an option.
Maybe we'll try another Mortise and Tenon joint soon then now we've got a bit more confident...
This is something I did many moons ago at University where I used stainless steel wire and bound the foot joint of a pair of tables to add decoration but also to add strength and rigiity...
I do like the use of stainless steel with natural wood! Those tables look gorgeous!
From aesthetic view, I see the value of the bands.
I was involved in a frame a few years ago where we used 3/4" dia s/s pins instead of oak pegs in some of the more visible joints (I also remember there being a Grand Designs where a similar approach was used too). The effect was lovely, though could be a bit much if they were used in all the joints!
Chopping out the waste on a mortise/bridle component.
Little bandsaw jig we made. The component rests on the 'cradle' so that in theory we have some sort of square, mitred shoulder cut with the inside of the bridle as the reference 'plane'...
Pegging a finished mortise and tenon joint.
Slackalice, don't know if you can see but the joint has it's shoulders on opposite mitres. We thought about it and thought the shoulder at the furthest end of the post would resist the tentacle dropping, the the opposite shoulder would resist it lifting in its cantilever...
The nearest face there ends up as the top face.
Blending the joint in on the bandsaw.
The mortise and tenon joint takes significantly longer to do with significantly more head scratching...
I'm loving the look of the tentacles you've fashioned already, the end result will look unique and stunning and I'm really quite envious!!
Here, here, wish I had a 'proper' job still. I really miss the thrill of turning something 2D into a 3D object for the first time. It's is immensely satisfying
Thanks again to you all for such an intriguing thread
Hear, hear, wish I had a 'proper' job still. I really miss the thrill of turning something 2D into a 3D object for the first time. It's is immensely satisfying
If only the pay was as satisfying for 'manual' work as it is for office-based...
But yeah, my job is fun sometimes...
This is what it's all about! Great thinking about the reverse / opposite mitred shoulders - that's border line genius! I'm gonna remember that one!
Your 2" butt mortice chisel looks like one of my framing chisels and certainly man enough for the task. Out of interest, what angle do you sharpen it to? I've found around 35deg works well for heavy work like that. Along with a big heavy mallet!
The bandsaw jig looks like an inspired bit of work too and probably reduces the number of people needed to lift and hold and guide the beam stock through.
Your joints are looking very tidy, how much draw are you finding works well for these?
Nice work there kayak, looks like you're getting the measure of the job in every sense.
kayak or slackalice - would it be ok to contact you with regards to a project im trying to draw up? Just to get your opinion - wont take long.
i see SA has an email in profile - can i send one out ok?
Hi scotia, no probs, mail away. I'm in all day today, waiting for Parcelfarce to collect a return to CRC...
The "..it won't take long..." always makes me chuckle tho!!
Hi Scotia, yes of course contact me.
I couldn't find your email in your profile though unless I'm missing it..
ok i'll send a mail then yeah i prob shouldnt have put the shouldnt take long bit in..
ok so i cant see my email either! its andrew*dot*gunstone*at*gmail*dot*com
Thought I'd look in on this to see if it's progressed. Any news?
Yeah it's Easter break so the students are not here.
The student doing the bench has also had to catch up on some curriculum obligations too so there has been a bit of a break.
I'm not complaining actually as It's hard work!
Back to it after Easter though. We have some catching up to do...
Good stuff - looking forward to seeing it in it's proper home.
Back after the Easter break to something of a disaster to be honest.
Virtually all of the tentacles have now split, some worse than others.
Where this is in big section I guess it won't matter too much but if this is happening further on down the taper then obviously it presents a problem.
Bit of a nightmare to be honest after all the work we've put in.
The tentacles were all outside so have had whatever the Easter weather threw at us, but I guess they were going to go whatever.
Releasing tension by cutting bits away like that in an uneven manner such as these twisting tapers must have been the doing of it.
Below is the worst one, which actually started to split weeks ago..
My first thought
was to chuck it all in the skip!!!was to go back to what I was talking about before with the metal bands tensioned around in various places.
It would be a shame as they are not so in keeping with the whole thing but I suspect would be a fairly ok compromise. Can't see what other options we have at the moment really and a bit gutted and hissed off with the whole thing..
One of the places we sell fencing blanks to uses steel bands, as do a few of the others actually, could be worth a try of local fencing suppliers or mills for a borrow, or at worst may have to take the material to them.
We and quite a few others use fabric straps which probably aren't of as much use (or clean looking) but suit our requirements.
Are these for round packs though? There are loads who do steel strappers for flat-faced items, but can't find any for round section as per the video above.
It's been very dry in the cold spell. With the change of weather some of the shrinkage may revert part-way, don't rush into any action.
Yonks ago I used 'band-it buckles' which work on steel straps. A quick google suggests they are still available.
Yonks ago I used 'band-it buckles'
Ah thanks Slowoldgit. They are available, though the tool is £190!!!
If I could hire one it'd be great.
I agree with you regarding the weather, but I suppose part of the problem is the timber will continue to expand and contract...Not sure how we get around that.
Mmm, not sure. The bundles of stakes are round, but rather larger curves of 1m dia. minimum, so probably what you mentioned.
In previous job, marquee king poles had steel reinforcement rings top and bottom, installed just like pick-axe heads, slide to fit on taper.
oh man - that's a shame.
Hope you find a solution.
First little try this morning with the stainless steel strapping tool we got. Hopefully this will help, as you can get a fair bit of tension onto it.
The clip 'heads' will be sited underneath, and the ends are actualy not sharp as I can run my hands over them pretty roughly.
The student is still working on essential coursework and so we've not started into the bench again properly yet.Posted 10 months ago #
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