PaRtZ Posted June 12, 2011 Report Share Posted June 12, 2011 (edited) So to get back into shape quicker, I've been looking into building a small packable bouldering overhanging wall for internal use (IE when its raining). Packable so that it's not permanent and I can use it in a student house next year without damaging the house itself. Initially I thought of something like this because it has the massive benefit of not having vertical supports infront of the wall that you might fall off into. However after a while I realised I couldn't get hold of the massive 2 long members (which scale wise would be about 12ft long) and also they would render the whole packable thing useless (it doesn't fit in my car, its too big by estate standards). Also you'd need a lot of counterbalance at the back to counter-act moments produced at the top AND its a bloody massive thing and would take up an entire room. So I've bit the bullet and gone for a standard right angle triangle with the hypotenuse being the wall itself. Ive managed to get hold of 10off 2m lengths aluminium tube so I'd like to use this for the frame. Its 32mm OD and a whopping 3mm wall thickness! If you're thinking its not strong enough - on its own it supports me standing on it in the middle (albeit it does deflect, but meh in a frame structure it would be better). Size wise Im a little undecided, but the height (or hypotenuse) will need two tubes joining together, not necessarily 4m high because I doubt Ill have room for that! The width will probably be 4m wide so again, I need to join two tubes together (in a temporary fixture btw, again, my car isn't 4m long) Now comes the problem because thats all I've got. Obviously I need some bits to join it altogether which Im going to have to pay for, but I've come up with a couple of ideas I need the engineers out there to play devils advocate with. Option 1: Kee klamps Kee make kee klamps in size 6 which accepts tubes of 33.7mm OD. The benefit is that due to their small nature, I could permanently fix the fittings onto 1 pipe, meaning that assembly only needs one grub screw tightening per join. Its also tidy, easy and simple. Cons: 33.7mm > 32mm => Fixed by adding a permanent shim (araldite) to the ends on the pipe increasing the tube OD at the ends to 33.7mm. Grub screw slip forces => Maybe Im just paranoid about this, but Kee suggest that for a 2m span I shouldn't exert more than 268kg of weight on the span. I assume thats a UDL and not a point load but as Im way under this I think I'll be fine... £££ => Little bit more expensive but I can live with that Option 2: Custom 'cut and file' notching Notching is basically milling the ends in the centre with a 32mm end mill to create the the OD profile into the tube. This creates a lovely fit and supports the tube from twisting a little. Once an end is notched, I could use a hollow starnut (because its a bigger bolt size) inside the notched tube, drill a 10mm/8mm hole into the un-notched tube (eeeek), add a distance tube to the inside (which would need to match the ID profile of the tube and probably be loose) and then bolt the two together. Whilst Im getting the standard 90 degree fittings notched, I could also make up some shorter braces across the corners to help strengthen the frame too (Notching) Cons: I don't possess a milling machine => Find a machinist and see if the tubes will actually fit. Might bump the price up a bit. Or mark out and use a half round file... Accuracy => If its not right, it definitly wont work... Hole weakness => Depending on what size bolt is used in the hollow star nut systems, drilling that sort of sized hole into the tube could weaken it a great deal. Once I've got the frame work, Ive then got to think of a way to get plywood onto it securely and then source holds. If I get it done quick enough, I might be able to get some free boards from work from used router boards, but for now I've got to get this done... Any ideas and CONSTRUCTIVE critism is welcomed. Solutions, things I havent thought about or even other ideas welcome too Thanks Edited July 25, 2011 by PaRtZ Quote Link to comment Share on other sites More sharing options...
Si-man Posted June 12, 2011 Report Share Posted June 12, 2011 (edited) Option 1. Got more flexibility in the set up too with just a few extra pipes. They usually come with grub screws to fix the pipes together too, use them at work for railings. Could always take the grub screw out, line it up, drill through the pipe both sides and nut an bolt it if you are worrying about slipping joints, use dome head nut and bolt if you're worried about catching yourself on them Edited June 12, 2011 by Si-man Quote Link to comment Share on other sites More sharing options...
PaRtZ Posted June 12, 2011 Author Report Share Posted June 12, 2011 Awesome thanks, Ill let it run a bit longer. My only other worry with that is slip between the shim + the tube. I know araldite is bloody strong but still I may have to try and find a welder... Quote Link to comment Share on other sites More sharing options...
Si-man Posted June 12, 2011 Report Share Posted June 12, 2011 Spot weld the shim to the pipe. Quote Link to comment Share on other sites More sharing options...
ZeroMatt Posted June 12, 2011 Report Share Posted June 12, 2011 Larger shim than you need and shrink/freeze fitting would sort it. Quote Link to comment Share on other sites More sharing options...
huge Posted June 12, 2011 Report Share Posted June 12, 2011 (edited) What about scaffolding clamps? I've no idea what diameters they come in but must be readily available second hand/cheap & more than strong enough? http://www.doughty-engineering.co.uk/cgi-bin/trolleyed_public.cgi?action=showprod_T24900 No need to bugger about with shims/drills then Edited June 12, 2011 by huge Quote Link to comment Share on other sites More sharing options...
Fish-Finger-er Posted June 12, 2011 Report Share Posted June 12, 2011 pretty much what si man said,only thing id be tempted to do, rather than an araldite shim, is 1 bolt right through. drill and tap a couple of small threaded holes in the kee klamp in the way it would want to shift, (i.e on a horizontal pipe, id put the bolt through horizontally) then drill and tap vertically, and just use a couple more bolts to pinch the aluminium tube to stop it moving up and down(and also to clamp it slightly) regards internal spacers in the aluminium tube, i think itd be easier to fix a permanent solid plastic/wooden bung in the end of the pipes (say 3 inches long)( thinking maybe polymorph for ease of use, or just wood, as its easy to turn down to size) glued into the end, then the hole drilled through the aluminium pipe and the bung. stops the pipe ovalizing/would solve the issue of the grub screws crushing the pipe etc. Quote Link to comment Share on other sites More sharing options...
King C Posted June 12, 2011 Report Share Posted June 12, 2011 As I've been recently looking at roll cages I wouldn't fully discount option 2 especially if your worried about getting the notching right. You can download programs in which you type in tube diameters and angles and it will plot a profile for you on paper which you print off, cut out and wrap around the tube. Then get busy with the angle grinder and grind away! No need for a milling machine. Or you can buy (possibly rent/borrow if you know someone with one) a tube notcher. But as you say definitely get anti crush tubes (preferably welded) in. Quote Link to comment Share on other sites More sharing options...
shamus Posted June 12, 2011 Report Share Posted June 12, 2011 (edited) Kee Klamps are pretty decent, my preference would be to drill a hole the other side of the clamp and striaght through the CHS. Then use a small bar straight through the lot as a locking pin. (if you want a little nut one end to secure it try and keep the thread away from the material clamb and CHS, it'll cut it easier then normal bar) Make sure the pieces are fully home when you drill then the majority of the force will transfer through the CHS rather then the pin. Quick assembly and very robust I'd also use some plastic shim on all connections to pad it, it'll reduce rattle and avoid wear if its reasonable toughness. Edit: aluminium might be too soft for the locking pin system I've suggested but I'm also concerned that you'll severely damage the soft ali grub screw clamping? Edited June 12, 2011 by shamus Quote Link to comment Share on other sites More sharing options...
forteh Posted June 13, 2011 Report Share Posted June 13, 2011 Much like everyone has said with the kee clamps, fit them to the tube, drill through the grub screw hole and pop a bolt through; will hold it far better and resist the twisting. Weve been doing this with kee clamps for years at work. Shim it out with some steel strip, you could always araldite it into position to save faffing with loose pieces. With the long members, you could replace them with wire ropes to allow your overhang and just use some shorter members to stop it folding back on itself. Counterweighting it could be a problem, but you might be able to fit a floor plate to the end of the long horizontals and slip it under a door Quote Link to comment Share on other sites More sharing options...
PaRtZ Posted June 18, 2011 Author Report Share Posted June 18, 2011 Mini update, nothing special May have found a way of joining 2 poles for free. Although kee do an internal coupling Ive made my own. Got hold of some short T45 tube lengths which the same OD as the ID of my pole (no jokes please). Put a jubilee clip on the T45 tube and slide it inside the poles. The clip acts as a collar to stop the joining pole from sliding all the way in. Cost: 69p per join Also found out that joining 2x 1.80m lengths and then putting my weight on it is WAAAYY too flexy! Going to cut a quarter of the length off each pole and join 2x 1.35m lengths together. If its still a bit too flexy, Im going to see If I can re-inforce the poles by shoving some more T45 down the centre of them... Kee klamp tests pieces are ordered, but still not here :/ Quote Link to comment Share on other sites More sharing options...
george_seamons Posted June 18, 2011 Report Share Posted June 18, 2011 I would replace the jubiliee clip with a bead of weld. They aren't really meant to take force in a horizontal plane. Id it slips, its gonna fall apart, which will hurt! Quote Link to comment Share on other sites More sharing options...
PaRtZ Posted June 18, 2011 Author Report Share Posted June 18, 2011 (edited) I would replace the jubiliee clip with a bead of weld. They aren't really meant to take force in a horizontal plane. Id it slips, its gonna fall apart, which will hurt! Unless I drill and pin/bolt the two together? The jubilee clip can be used to give a measure of how deep to push the joiner in, otherwise it could take a while of farting around getting it to line up, and its a very tight fit already! I understand your point about the force though, will take heed. EDIT: Pics of size Edited June 18, 2011 by PaRtZ Quote Link to comment Share on other sites More sharing options...
Matt Vandart Posted June 18, 2011 Report Share Posted June 18, 2011 As I've been recently looking at roll cages I wouldn't fully discount option 2 especially if your worried about getting the notching right. You can download programs in which you type in tube diameters and angles and it will plot a profile for you on paper which you print off, cut out and wrap around the tube. Then get busy with the angle grinder and grind away! No need for a milling machine. Or you can buy (possibly rent/borrow if you know someone with one) a tube notcher. But as you say definitely get anti crush tubes (preferably welded) in. Link please Quote Link to comment Share on other sites More sharing options...
Luke Rainbird Posted June 19, 2011 Report Share Posted June 19, 2011 Google "TubeMiter" Quote Link to comment Share on other sites More sharing options...
PaRtZ Posted June 21, 2011 Author Report Share Posted June 21, 2011 (edited) Mini bump, got the kee clamp tests today. Found a perfect shimming tube too... The shimming tube slotted over the structure tube pretty easily, so obviously when I clamped the kee clamp up it didn't grip at all and just slid out. So I cut a slot (on my couch I might add...) into it so when the clamp compresses against the tube, the shim shrinks in ID until it grips the tube. So I'll order the remaining clamps and get building. I am still going to remove the lug screws and drill right through although I need to resist temptation to leave it.... Got to source plywood for the back now and eventually some holds! Edited June 21, 2011 by PaRtZ Quote Link to comment Share on other sites More sharing options...
shamus Posted June 21, 2011 Report Share Posted June 21, 2011 Use some scrap wood as spreader plates as well as some chunky washers behind the holds, It'll save your Ply! Especially if have any jugs or pockets which will give a lot of lever on the wood! Quote Link to comment Share on other sites More sharing options...
PaRtZ Posted June 24, 2011 Author Report Share Posted June 24, 2011 Who thought I was mad? Quote Link to comment Share on other sites More sharing options...
Ash-Kennard Posted June 24, 2011 Report Share Posted June 24, 2011 hurrayyy Quote Link to comment Share on other sites More sharing options...
PaRtZ Posted July 14, 2011 Author Report Share Posted July 14, 2011 Another Bump, we have progress. I need to cut a slot out of this board to allow the vertical supports to fit through, and I also found out the plywood needs supporting/fixing in the centres of the longest sides as they're a bit flexy. This top picture is of the wall on it's side. I bought the plywood in 3 sections so that they fit in the boot of most estate cars quite easily. I need to brace across the centres with 2 extra poles for a bit more rigidity. Possibly overkill, but meh, it wont fall atleast. Quote Link to comment Share on other sites More sharing options...
PaRtZ Posted July 25, 2011 Author Report Share Posted July 25, 2011 Another update. Route setting a bit limited at the moment.... I finally found an 11mm drill bit so I started gluing and pressing the T-nuts in tonight, more to resume tomorrow... BTW if anyone can get hold of some steel pipe can they get in touch? I need about 2 foot of around 33.7mm OD x 1.7mm (will get more accurate measurements if someone replies) for me to use as shims. Thanks... Quote Link to comment Share on other sites More sharing options...
CalopS Posted July 25, 2011 Report Share Posted July 25, 2011 Looks like its going to be pretty sweet Matt! How are the injuries? I'm waiting for my boulding mat to be made/posted at the moment. Outdoors is scary without a sea of foam below you! Quote Link to comment Share on other sites More sharing options...
PaRtZ Posted July 25, 2011 Author Report Share Posted July 25, 2011 Ahh what mat have you gone for? Arms still not right but its definitly getting stronger. I did some bouldering the other day (2 V0+'s yo!) and it didnt hurt then. Im just very wary of highball stuff atm which is doing my mind no favours! Quote Link to comment Share on other sites More sharing options...
CalopS Posted July 25, 2011 Report Share Posted July 25, 2011 Ive ordered a climbing factory ground hog mat. least with a wall at home you'll be able to build up your strength everyday in small sessions. Looking forward to see it finnished Quote Link to comment Share on other sites More sharing options...
PaRtZ Posted July 26, 2011 Author Report Share Posted July 26, 2011 (edited) Put all of what Ive got together and finished off drilling the first board. Also drilled off the middle board to suit the attachment holes and realised I have another problem.... Currently in slab mode: The frame is flexing quite a bit due to the weight of the wood. My aim is to get another piece of tube to brace lower down (mid-point). If thats not good enough, Ill have to get MORE articulated clamps and do a double brace using the one shown as-well. But it does work Edited July 26, 2011 by PaRtZ Quote Link to comment Share on other sites More sharing options...
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