Hows it going guys,

Yeah....I like using a stick, rather than trekking poles. Theres just so much sentimental value in the one I have....and well, I dont know....theres just something about trekking poles that dont suit my personality.
Anyway, I just finished constructing a grip for it, and I was wondering if anyone out there has any insight into how I might now make the stick collapsible - so as to make it more packable, and more importantly, so it could serve as my single 42" support pole for a Gatewood Cape (granting it receives favorable reviews). The stick itself is currently about 50" long, so a single separation point, most likely directly below the grip, would probably be ideal. The difficulty most likely lies in finding a strong weight bearing system that still allows me to manually seperate the two pole pieces while in the field. I've been trying to come up with something myself, but I'm really not too saavy in the Make your Own Gear department, so any help would be greatly appreciated. Thank ya!

Dave:)

Edited by davidp80 on 03/09/2006 22:06:25 MST.

What about the threaded metal connection you seee in poole cues that can be taken apart?

Steve,

That was my initial idea...but I'm a bit unsure as to how I would go about doing it. You're right though, that definitely could work, if only I could figure out how to do it. Perhaps I'll go out for a couple of drinks tomorrow evening, and evaluate the system with the aided eye....

Thanks,

Dave:)

I'm pretty handy at fixing all sorts of things - as long as wood is not involved, but I am, without a doubt the world's worst carpenter - bar none. No...there is nothing anyone can do to help me in this area. [ok. i can frame, but forget finishing - of any sorts - too artistic for my brain. if ugly finishing carpentry/woodworking won prizes, i'd have no competition. ok...now, to get serious.]

Yet, I think this one is somethiing I could actually do, especially since pretty doesn't count. I'm not familiar with pool cues, but based on the other Poster's brief description, I've seen similar joinging mechanisms in store bought Coat/Hat trees.

I've actually got some of this hardware in the basement which was taken off of old, broken, now burned as kindling in my coal stove coat tree. I might give this project a go myself. Sounds like fun.

Here's what is running through my mind right now...

1. get the hardware you think that you will need. the local hardware store will have what you want. the male side will be threaded on both ends with a splined divider area/ring. the male threaded part that is screwed into the wood will have a wood thread pitch and cut. the other end of the male piece will have a machine/metal thread pitch and cut. the female end will have a threaded insert to accept the male machine end. the outside of the female will either be a wood thread or fully knurled and/or splined for press fitting (hammering/pounding) into the wood.

2. cut your walking stick at the appropriate length.

3. This is the most crucial and error prone step in this procedure and must be done correctly. Drill holes in each end of the wood which is the same diameter as the central unthreaded portion of wood screw ends of the hardware. This way only the threads cut into the wood and you won't run the risk of cracking your wood or not having enough bite from the threads. If you're still concerned about cracking the wood even from drilling and then screwing in the joining fasterners, then you can wrap your wooden staff with some cloth and bind it tight with some hose clamps (local auto supply store will have them) for extra support when drilling and screwing. This will help if the wood is very hard or old, and you fear that it might crack. Make sure that the holes are deep enough to accept the full wood threaded length OF THE SIDE/HALF OF THE HARDWARE THAT IS TO BE INSERTED INTO THE WOOD. If it is difficult to screw these fasterner halves into the wood, drag the wood threaded ends across an old bar of soap before attempting to screw them in. You'd be better off getting advice on using a carpenters glue or some type of bonding agent on this wood-to-metal interface. I really don't know anything about whether this should be done or not.

Note: About drilling the holes. It is absolutely essential that the holes be drilling "perfectly" vertical for the completed, assembled walking stick to be straight. Find a drill press to do this. A hand drill with one or two leveling bubbles might be used if you're skillful and careful, but it might shift while drilling making the hole on an angle.

One other thing. Since I am so bad at carpentry, I often drill in two, three, or four steps, beginning with a very small bit, and working my way up to the proper size. So, a pilot hole first, at the very least. In this case, I'd go with the drill press, or an end mill with a drill bit. If you know anyone who can work with a table leg, maybe they have the right equipment. This is really way beyond me.

Best bet, take your walking stick to a professional woodworker and ask them to cut it and drill it. They've got the right equipment for "perfectly" vertically drilled holes. You can easily take it from there. Take your joining hardware with you so the woodworker can drill the right diameter and depth holes.

4. thread both the male and female pieces of the fasteners into the wood. Press fit, or carefully hammer the female end in if it is not threaded.

5. now you can simply screw the two pieces together.

6. if there is a gap, then you need to insert (screw, press, pound) one or both of the pieces of the fasterner deeper into the wood. If you have trouble doing this, then the holes need to be drilled deeper. Remove the hardware (only if screwed in) and return to step #3 above. If it's press fit then you might have a problem. In this case, you might have to countersink the male half so that the little portion of the female half that is extending too far can be accepted and you can screw the connection down tight.

Keep in mind that this joint is going to be a weak point in you walking staff, and may be subject to unexpected failure when stressed/loaded during use on steep terrain (the worst time for a failure!!). You may want to bind, for added strength, both ends of the cut wood, near the joint, with some type of band/banding that is more flush than hose clamps.

--------------------------------

I'd appreciate any feedback from real carpenters, woodworkers, hobbyists, out there. Please correct any errors, or enhance any deficiencies. I don't want to give bad advice.

Edited by pj on 03/10/2006 09:18:34 MST.

Wow, thank you Paul. You pretty much elucidated the basic, fuzzy process that I had going on in my head, and I feel a bit more confident now about doing it myself, but moreso in the actual construction process than finding the parts I need (I'm always lost in a hardware store!). Finding a professional woodworker is something I hadn't considered, and may not be that expensive. Maybe I'll go looking for the parts first though before thinking about step # 2....lets just hope I can make it to step # 2. Thanks again,

-Dave:)

Edited by davidp80 on 03/10/2006 08:30:12 MST.

Dave,

The joint you're considering isn't as easy as it appears.

A threaded insert in a pool cue works because there aren't any bending loads across the joint. In theory this is also true for a treking pole. In reality I've found there are significant bending loads imparted to a pole when the user loads the pole to catch their balance.

Additionally threading anything into the end grain of wood is never a good idea.

My advice would be to save your sentimental stick for day hikes and get an adjustable aluminum pole for the cape.

Robert

Edited by procab on 08/27/2007 00:01:25 MDT.

I think if you use something threaded... it would be best for it to be a cylindrical / tubular connection rather than a butt joint with a small bolt (like a pool cue). What I'm envisioning is a metal collar that would slide over both ends of your stick... hopfully by at least an inch on both ends... but the more the overlap... the better... and there would be theads on the inside of the collar. Basically... what I'm saying is that the "male" side of the connection would be the full diameter of your stick. That sounded kinda funny :P

Edited by davidlewis on 03/10/2006 09:55:07 MST.

Robert,

You could be right, and more than likely are, based on your experience. It does have sentimental value...like I said, but then again....it is just a stick, and if something goes wrong, well, it wouldnt be the end of the world. I definitely would like to give this a try, and I appreciate your opinion.

David - that does sound like it could be stronger than an internal threaded joint...hmm....I wonder if I could still dismember the two stick pieces while in the field with such a strong bond? Thinking....thinking....

Thanks guys,

Dave:)

Robert,

What's your take on either a 12"-24" removeable solid Al dowel, or a thick walled Al tube which when inserted into the drilled out center of each "half" of the cut walking staff? Holes drilled clear through the staff and central Al shaft would enable pegs (two pegs on each end???) would hold the entire assembly together? Duct tape wrapped around the staff to hold the pegs in place? Even it's a better idea (???), perhaps the joint could not easily be made tight and still have pegs easily field insertable and removeable?

Also, regarding screwing into "end grain", keep in mind that the pieces are not in tension (other than as a side effect of bending moment). Does this change anything as to this issue?

Edited by pj on 03/10/2006 13:41:43 MST.

Paul... other David here... but I think that any removal of material from the cut ends would make the joint not as strong as it could be. That's why I like the idea of a metal collar / tube on the OUTSIDE of the cut ends of the stick. The lateral/diagonal stresses would transfer to the outer metal collar. With drilled out ends and a long metal dowel insert... the stresses would transfer from the center out to the wood... and potentially break. It would be prettier tho' since you wouldn't see any metal with the stick assembled.

As for the fastening part of it... it could be either threaded or simply lynch pinned thru.

Edited by davidlewis on 03/10/2006 11:04:30 MST.

David, I like you sliding collar idea - pretty clever. Also, I understand the concerns about lateral/bending loads which was why my bold warning about it being a weak was added. My hope is that the suggested steel bands holding the wood in compression would ameliorate, somewhat, this weakness. Also, the central dowel/tube, in my second suggestion, is an attempt to further reduce this problem, since it is quite long (12"-24"). If the joint is tight (in either suggestion), some of the bending is minimized by a portion of the faces being placed into compression, causing the bending loads to distributed over more than just the central core. However, even this does not cause the loads to be distributed over as great an area as the intact unmodified wooden staff. Even taking these measures, I still expect this is the most likely failure point.

In order to do a stick with the maximum amount of side load strength, your going to have to go with a collar. The collar is still a severe weakpoint point, but it works.

In order to fasten it, I peronally would go with an epoxy to hold it in place. The less material you remove from the stick, the better.

If your seriously interested in this, you might want to talk to some traditional archery bowyers who produce 2 piece takedown bows.

Kinda like this one http://www.oldbow.com/saxon_archery__two_piece__take.htm

Edited by RavenUL on 03/10/2006 12:24:02 MST.

Agreed. I like the sliding collar idea too, but am still a bit unsure as to how this would work as a threaded connection - i.e. wouldnt the wood on both connected halves need to have a threaded surface? I guess 'sliding' both ends into the metal collar was what you really meant, and I could see this working (I'm not worried about the aesthetic value), but what are you reccomending that I use as tighteners/fasteners to keep the collar in place once it has connected both ends of the stick? Perhaps a couple of small, threaded woodscrews on either end to penetrate both the metal and the would might work, but then again, this would most likely be sacraficing the weight bearing capacity of the stick in a similar way to that of the pool cue method. I think we're getting close....

Thank ya!

-Dave:)

Thanks for the link Joe, but I'm a bit confused about your reccomendation for using epoxy (excuse my ignorance). I assume you are suggesting that I use epoxy to attach the collar to one half of the stick, so that an additional external fasteners are only needed on the other end, rather than on both?

Thanks,

Dave:)

Edited by davidp80 on 03/10/2006 12:31:00 MST.

I don't really know how the collar would fasten David... the main thing was just the structual idea of having a metal "tube" around the outside of the joint. It would be ideal is this collar / tube was threaded on the inside... and you had some kind of matching threaded "cap" or something for the male end of the joint. OR... you could just use lynch / cotter pins right thru the collar and wood... but that would be loose and rattle-y.

David

The only bows I make are 1 peice "selfbows" so Im tapped out already on the process of making a a 2 peicer. As I said, you might want to talk to bowyers who do this type of work. Generally bow string tension holds the peices together, but they might have a few ideas on how to give you some solid joining here. Another resource might be SCA type spear makers or other armorers who make spears/pikes/halberds/etc with long shafts but that need to be taken down to fit in the back of compact cars.

The point on epoxy, which I now see was unclear, was to use a gluing agent, rather than pins or an over reliance on threading. As a weakpoint on the shaft, youll want as much material there to hold it all together as possible, and youll want to reduce to an absolute minimum any drilling, cutting, or thinning. Youd probably be OK removing a ring or two of wood from the shaft to ensure a flush fit of the collar, but Id be wary of much more stock removal than that.

Thinking out loud here, you may be able to get some sort of system milled for you that would provide a male and female threading that could be epoxied to their respective cut ends, with the reenforcing collar epoxied to the outside? (edit for clairity - the color is epoxied ONLY to one half of the shaft. The other half of the shaft slides into the collar. It is not glued. It is held in place in the collar by a minimal amount of threading.)

If anything goes wrong and breaks free, it will be the epoxy... and it would take quite a bit to make good epoxy let go... but your wood would still be in good shape so you could fix it good-as-new when you got home.

Edited by RavenUL on 03/10/2006 13:01:41 MST.

David and Joe,

Thanks for the clarification - I can visualize the process you are describing now. I think my best bet right now is to make a trip down to Lowe's, and see what I might find lying around.

-Dave:)

Sliding collar would slide down and 1/4 turn to lock it in place. Grooves with notches would slide over some stops that would hold collar in the locked position.

Well, I came across a few different things at Lowe's that might hold some promise. The first were some small matching Conduit's, which in our language translates to 'matching male and female collar parts that can be threaded together and have small screw inserts to attach the collar to the stick (epoxy would probably be used as well).' This could work, but the Conduit's were awfully heavy....too heavy in fact.
Also in the same aisle I found some PVC fittings, which are more or less lightweight plastic Conduits without the screw inserts. I bought 4 of these (two male, two female) in 2 different sizes (1/1/2" and 1/1/4", which I believe refers to the diameter of the threaded portion of the collar), and both were too big (my stick slid right through the collars). In the event that the 1/1/4" diameter pieces are the smallest they have, I was thinking about imrovising and somehow thickening the collar attachment point of the stick. My initial thought was that I could tightly wrap duct tape around the stick (perhaps even sticky side out, which may combine well with the use of epoxy in attaching the collar, but may also slide over time...), until I came to the desired thickness. It all sounds pretty crude....and its definitely not going to be the best looking hiking stick on the block, but....does it sound like a reasonable enough plan?

Thanks,

Dave:)

Edited by davidp80 on 03/10/2006 15:38:27 MST.

Kicking around this design problem while earning a living today I came up with a similar idea to pj's internal tube with pins. The concealed tube appealed to me because it maximized the asthetics of the sentimental stick.

If asthetics aren't a big concern the external metal collar proposed by several people sounds like the best solution. That type of joint has proven very durable in such uses as attaching a wood dowel to a steel shovel.

David P - you need to find a tube that is snug fitting to maximize longevity. Avoid the duct tape shim.

pj - if you want further clarification on the end grain thread problem let me know. I don't have the time right now to answer.

Regards,
Robert

Id stay away from the duct tape shim too...

whats the diameter of your walking stick, and does it have a strong taper?

Yeah...perhaps I should stay away from the duct tape. The diameter of the stick, at the point where the collar is going to be attached, is aproximately 1". Overall, the stick has a slight taper, but is no less than 3/4" at the bottom most point. I'm going to make another trip over to Lowe's today and see what I might scrounge up again. Thanks for everything guys!

Dave:)

Sorry if this has been mentioned before in the thread; I didn't read all the way through.

I've used grey pvc threaded fittings sold at hardware stores everywhere for electrical conduit, along with something like gorilla glue or liquid nails. Also the tip is key and I used a chair leg bumper. One good rocky trip will wipe out a bumper....

I haven't had problems with weakness or failure and still have a 2 part stick that went from the rim of the Grand Canyon to Deer Creek falls and then over to Thunder River and Tapeats and back. Agree it seems to be more sorta soulful to carve your own out of native wood; though I've become a synthetic 2 pole hiker. Can't beat it for stability and downhill.

Last night I was also thinking more about the safety, rather than function, of this collapsible walking stick. We all pretty much agree that there is going to be a weak point in at the separation joint, whether major or minor. I was then thinking about how much trust I'm going to be putting into this stick...while threading a narrow strip of land next to a steep dropoff, while descending down a steep, rocky slope, while keeping myself balanced in fording rivers, etc., and perhaps....well, considering how much I'm going to depend on it for my safety, perhaps this isnt the best idea in the world. But then again....I have been known to overemphasize the danger in certain situations....what do you guys think?

Dave:)

Cola,

Thanks for the feedback! The system you described is the answer I came to yesterday while roaming around Lowe's, and I just have to go back and find a couple of smaller diamater PVC fittings. I didnt think about the tip though....that might be a worthwihle consideration. I'm still a bit leary about the safety though....errr...I'm going to make a trip down to Lowe's regardless to see what I can find. Thanks!

Dave:)

Well the hike I described is about as steep and rocky as it gets. The conduit is dirt cheap, very light and pretty strong. Actually stronger depending on the strength and seasoning of the wood than a collapsible trekking pole, at least for Perpendicular stress ( I'm no engineer so I may have the wrong terminology but if you had to hang from the thing...... On the other hand it'd be hard to put enough end to end or parallel stress on any pole to break it. The thing about the pvc is it's cheap so you could always experiment, but I think the strength of the stick/wood is going to be your limit. After all the fitting is basically filled with the stick.

Biggest problem I had not having a shop and a spoke lathe or whatever was rounding off the ends of my sections to fit snugly inside the conduit joints. I did have a bench grinder so I used that and "eye-balled" it.

Cola,

Did you shape one half of the stick so that it fits snugly inside the threaded portion of the PVC conduit as well, or did you just fit the ends so that they fill the inside of the conduit's to the edge of the threads?

Thanks,

Dave:)

Well guys,

I just finished constructing the walking stick. I used two pieces of 3/4" threaded PVC Conduit fittings for each each of the attachment points. The total stick length is aproximately 50 1/2", and when unthreaded, I'm left with one 8" piece, and one 42 1/2" piece (the latter will serve as my single 'trekking pole support' for the Gatewood Cape. I didnt bother using glue or epoxy to attach the Conduit pieces - the Conduit pieces were just slightly undersized (they wouldnt slide over the stick ends), so a bit of minor carving at each end of the stick allowed me to partially twist on each Conduit piece, and a some steady hammering secured them the rest of the way. When threaded together, the two stick ends are essentially touching each other, and I can't sense any weakness in the joint even when leaning on the stick with my full weight. My only concern is that water (when its raining) might leak into the joint as it runs down the stick, which may or may not loosen the Conduit pieces. However, field repair seems as if it would be easy enough, as there are more than enough solid rocks out there that could be used for pounding.

For the grip, I used some leftover 1/8" GG thinlight pad that I had no use for, and attached it to the stick with the aid of inside out duct tape that was tightly rolled around the top edge. At first I thought the grip might slide (since its not directly attached to the stick itself), but even with all my strength, I can't seem to get it to move. The final weight is 14.9 oz.

The one thing I have yet to do is to attach a tip to the bottom end. I intend to attach a matching 1/2" PVC pipe tip with the aid of epoxy.

As far as aesthetics go...well, its not the most pleasing thing to look at, but I definitely think it has its own unique taste. I'm not sure what kind of wood I'm using (maple maybe?), but when I shaved off the bark today, I found some beautiful dark purple linings that I think will compliment the cheap PVC plastic well :P

If you would like, I could post some pictures on Monday for anyone who is interested in trying themself, or for anyone who is just genuinely curious. Thanks again for all of your help!

-Dave:)

Edited by davidp80 on 03/11/2006 13:53:07 MST.

Robert, Sure, whenever you get a chance, at your convenience, please post back and educate me on the endgrain issues -- I'd appreciate it. Thanks for offering.

One question... why all this just for 8 inches? Is there no way to pitch the shelter will the 50 1/2" stick?

David,

With the Gatewood Cape, the pole is pitched inside the shelter, and with more than 42-43" of pole height, the bottoms of the shelter would no longer be snug with the ground (which kind of disregards the purpose of using a 'full protection' tarp in the first place).

Dave:)

Here's a thought... I know we all hate to add weight if we don't need to... and love the idea of dual use... but gossamer gear sells 42" shock-corded carbon fiber tarp pole that only weighs 1.2 oz. They sell it for the SpinnShelter. It's not cheap tho'. The aluminim pole set is half the price... but a bit heavier. Maybe it's worth the extra 1.2 oz (and money) to have a solid walking stick that you know you can trust?

Edited by davidlewis on 03/11/2006 17:46:44 MST.

David,

Thanks for the reccomendation. Its odd that you mention the GG carbon fiber poles, because I do have a set of them for my Spinnshelter (which is currently up for sale....so I may in fact not have them for much longer). I had thought about just carrying along the 42" front pole for use in the Cape....but....I really just wanted to be able to use 'trekking pole support' without the use of a trekking pole. Now that the construction of the stick is completed and I've done a bit of testing with it, I have enough confidence in its support strength to carry it without feeling I need a back-up pole in my pack. You're probably right though....my walking stick wont be as reliable over time, and carrying the carbon fiber pole would only slightly increase my pack weight, but....if ya never try, ya never know. Plus, carrying my homemade collapsible walking stick just plain makes me feel good :)

-Dave

David... if you end up selling the SpinnShelter without the CF poles... would you consider selling them to me? :) I'm getting a LuxuryLite cot with sidepoles that double as hiking sticks... so now I need an ultralight pole set for my SpinnShelter. The cot with a 1/8" nightlite pad is actually going to result in a net base weight LOSS if you can believe that! (I use a 3/4 thermarest prolite now).

Anyway... just thought I would mention the dedicated pole idea... since it's so light. I imagine the hardware you added to your stick is not much less than 1.2 oz :) But yes... it's much more fun to use something you made yourself... for sure. Are you going to post a pic or two?

Edited by davidlewis on 03/11/2006 20:40:56 MST.

David,

Surely. If it turns out that whoever buys the Spinnshelter doesnt want the CF poles, we could definitely try to work something out. How has your Spinnshelter been treating you? I havent had much of a chance to try out mine....before deciding that I wanted to switch to a ponchotarp (errggh....gear innovation!).
I'd also be more than happy to post a couple of pictures of the walking stick this next week. The wood really is beautiful...I just can't decide whether I want to stain it or not (I'm a bit torn on whether I really want the stick to shine). Thanks David,

-Dave:)

Edited by davidp80 on 03/11/2006 21:02:23 MST.

David L., I'm curious about the warmth of the cot. Never used one, nor a hammock for camping. I'm sure both are more comfortable than sleeping on the ground.

My question to you is: since there is a constant air exchange under the cot and your body can't slightly warm the ground underneath you, won't you need more insulation underneath you for the same overnight temps with the cot? Not saying you still won't get a weight loss, but other than summer, just wondering if you might need more than 1/8" of closed cell foam underneath you? So, what do you or anyone else think about this? Faulty observation? Valid point?

Edited by pj on 03/12/2006 03:34:01 MST.

Hey Paul. Yes, I may need more than a 1/8" pad for insultation.

Also, bear in mind that thick pads are doubling as insultation AND padding. So even tho' we all use 3/8" pads... because anything less is just not comfortable... much of the time we proably don't need the amount of insulation provided by a 3/8" pad. I know that a cot / hammock has the added issue of air circulating underneith... but anyway... we'll see how it goes.

Edited by davidlewis on 03/12/2006 06:18:13 MST.

Hey again.

I rechecked the calculations Paul. I actually am gaining one ounce. It had worked out to no added weight before when Bruce was talking about using carbon fiber struts... but the carbon fiber struts idea didn't work out.

Sorry for the "thread hijack" BTW... but I guess since the stick has already been made... it's not too bad a violation :)

One thing you will note is that I'm subtracting the weight of a ground cloth in the "After" calculation. Since most of me and my pad and bag will be completely off the ground... I figured I don't need it. Since the cot is not full length... there will be about 1.5 to 2 feet of me and my bag / pad sticking off the end of the cot. My plan is to sew a bit of tyvek or plastic to the underside of the portion of the Nightlight pad that will be sticking off the end... just to keep out rising damp / ground water.

Before:
---------------------------------
Thermarest Prolite 3 short: 13.44 oz
GG Polycryo Ground Cloth: 1.34 oz
Komperdell C3 poles: 10.16 oz

base: 15 oz
carried: 10 oz


After:
---------------------------------
44" LL TrailStiks: 5 oz
LL ExtremeLite Cot (packed weight): 12 oz
SpinnShelter Carbon Fiber pole set: 2 oz
GG Thinlight 1/8" pad: 2 oz

base: 16 oz
carried: 5 oz

Also note that all of the weights in the "After" calculation are as spec'd by the manufacturer... not as actually weighed by me... since I don't actually own any of those items yet.

One final thought... to me... ultralight is not about weight... it's about ultra-efficiency. The low weight is a side effect of being ultra-efficient. And even tho' I could sleep on a postage stamp sized gossamer gear egg crate pad or what have you... the issue there is that I will not sleep... and a good night's sleep is a HUGE efficiency issue. If I'm only getting a few hours of crappy sleep... it doesn't matter how light my pack is... I'm not going to enjoy myself and the hiking will be MUCH more difficult.

Edited by davidlewis on 03/12/2006 06:24:14 MST.

David,

I forgot to ask. Where can I contact you in the event that I will have the CF poles for sale. Thanks,

Dave:)

David,

I just sold the Spinnshelter without the CF poles. I'll give them to you for $35 shipped if that sounds alright. They're basically brand new, only used 2-3 times. You can email me at davidp80@yahoo.com if you'd rather take care of things there. Thanks,

-Dave:)

Edited by davidp80 on 03/12/2006 10:29:32 MST.

Hey guys,

I was hoping to post a few pictures, but couldnt quite figure out how/couldnt find any information here on BPL. Any help would be appreciated. Thanks,

Dave:)

Dave,

Go to photobucket.com and make an account. Upload your pictures there. Once you have done that, select the picture you would like to post(there is a check box directly underneath the photo), then click the "Generate HTML and IMG code" button. This brings up several differnt options for the appearance of your pictures(it's better to use the clickable thumbnail so as not to eat up bandwidth) . Choose the one you want, then copy and paste the HTML code to the forum. Your picture will the appear in your post. Try it in the User Test Forum to get a feel for it. Good luck, and I hope to see some good pics.

Roy

Edited by oiboyroi on 03/13/2006 15:22:47 MST.

Thanks for your help Roy. Uploading those pictures really does take forever! I think I everything is in order though, so here we go:

<center>











</center>

Simple, but effective.I haven't had the opportunity to use it as for tarp support, but I imagine it may exceed the peformance of normal, more flexible aluminum poles. I also still have to find some kind of a tip to use - I was thinking about just buying a replacement tip from GG. Thanks again for the help everyone. This was an enjoyable first project for me (I just got underway with my second today....a new PG 3D quilt :)

Edited by davidp80 on 03/13/2006 16:32:47 MST.

pj,

The bond between wood fibers is relatively weak. This results in negative properties such as splitting and splinters (ouch). If you crosscut a small wedge from the end of a board it is easy to break the pointy end off at a thickness of 1/8" to 1/2" depending on the species of wood.

The problem with screwing into endgrain is the screw threads cut the long wood fibers into little pieces that rely on this weak bond for anchoring. Returning to the wedge example above, visualize a spiral shaped wedge around the screw in endgrain.

Destructive testing is very revealing. An endgrain screw placed in tension until failure results in a clean hole the outside diameter of the threads.


The same screw threaded in the face of the same board and tensioned to failure results in far more damage to the board because the threads have done less damage to the fibers upon its insertion. It was also much more difficult to pull out because the stress was spread into the board via the fibers.


While this the weak bond between wood fibers might be considered a negative it has been exploited by humans for a long time. The manufacture of shakes, shingles and split rail fencing come to mind. Most likely even earlier in history humans exploited this property for making kindling from bigger chunks of wood.

Regards,
Robert

Robert, Many thanks for the reply. I understand what you've explained, and I've seen similar damage to your pics. Most recently, when "xxxxx" didn't shut my front storm door while delivering a package (yes...it was some gear) in all day heavy rains with 40mph wind gusts (the rain and wind began over 9hrs before delivery and was ongoing at the time of delivery). The return was ripped out of the door frame and the storm door banging about when I got home from work. At least no rain penetrated the edges and seals of the inner door.

My question regarding use of screw type joining hardware is that the two pole sections aren't going to be in tension. They will be subject to bending moments and compression. Only one-half (the outer half relative to the direction of bend) of the threaded insert will be in tension. Do you feel that this will make a difference? Please advise when you get a chance. Many thanks.

pj,

You said -

"the two pole sections aren't going to be in tension. They will be subject to bending moments and compression"

You are correct but you're focused on the poles and not the connector which is the weak link in this exercise.

You said -

"Only one-half (the outer half relative to the direction of bend) of the threaded insert will be in tension."

I think you're missing where the fulcrum is located. I believe it would be at a point on the circumference of the stick, which would place the entire insert in tension.

Robert

Understood. Clearly this end grain threading is weaker than threading in through the grain as in your second photo (looks very similar to my door jam after the "xxxxx" delivery accident).

However, if the insert is subjected to bending forces, the inner radius will be in compression, and the outer radius in tension. This is the nature of bending. The entire insert will want to rotate about the fulcrum point you mentioned in the direction of the applied bending moment, but will be held somewhat vertical by the surrounding wood reacting to the compressive loads the threaded inserts are exerting against the wood holding them in place. Since the threaded inserts are many times longer than their diameter, I don't think that any appreciable rotation about the fulcurm point you mentioned can occur. Perhaps I'm mistaken though? Over time, repeated loading cycles my cause the metal insert to do gradual damage to the surrounding wood in contact with the threaded insert, I would imagine.

What did you think about the dowel or hollow tubing, pinned into position? Is that superior, to your mind, to the threaded insert alternative?

pj,

To avoid confusion leave the material (wood) out of the equation. The fulcrum is the inner radius (r=zero) and is in compression. Everything to the outside of the fulcrum is rotating on a radius and can only be in tension. Basically the joint has created a huge stress riser that has decreased the effective diameter of the tube by 50%. Correct? Or am I missing something? If one needed a joint in a steel tube a flange would most likely be best because the tension could be better spread into the OD of the tube.

I agree, gradual damage from cycling is the cause of greatest concern.

Your pinned dowel was a better solution, although your suggested length was a bit long, IMO. The pinned outside collar is an even better design because it helps prevent splitting that the inner dowel would create through bending cycles.

I gotta go. I'll check back later.
Robert

Robert, thanks for having this exchange of ideas with me. No. I don't think that you're missing anything. I'll go give it some more thought until I've nailed everything down in my mind and then I think that I'll see it precisely your way. The flange is definitely the way to go if a threaded insert was used. That was in my mind also, and didn't originally suggest it since I was unfamiliar with easy to find hardware that would allow David to complete his project. Other than appearance, I agree that the outside collar is more structurally sound. Thanks again. BTW, I checked out some of your handiwork. Nice pics; nice work. You have my envy.

EDIT:
>>"I think you're missing where the fulcrum is located. I believe it would be at a point on the circumference of the stick, which would place the entire insert in tension."

Robert, Your comment "I think you're missing" IS EXACTLY CORRECT. Boy, did I miss that point. Your mention of "fulcrum" was the key for me - once I stopped and thought about it just a bit. It was the key point I was neglecting. When the fulcrum point is considered, it's clear that the entire threaded insert, is all in tension. The fulcrum point being at the outer circumference of the staff will want to pull/rip the entire threaded insert out of the wood when the bending loads and the hiking staff radius act as a lever (i think m times c over i is useful here for analysis). Now, this, i.e. a catastrophic static failure, might not actually happen depending upon the loading, but that would be the what the bending loads would try to do. Good point. Thanks for taking the time to share and enlighten me as to the key concept that I was missing.

Edited by pj on 03/16/2006 10:40:55 MST.

You've got it Dave! Just one cautionary note. Wood moves. It expands/contracts, twists and turns. Glue the conduit joints!

Haha...good suggestion. I hiked about six miles yesterday with the stick.....and the strength of the joint itself only lasted about five without the bottom conduit piece slipping. I used a liberal amount of epoxy last night that will hopefully keep it in place. This morning, I'm going to work on installing a small compass to the top edge :)

Thanks for all of your advice Cola,

Dave:)