Need Help on a Project!

[SweetErika]

So, we're making the munchkin a platform swing that's kind of like the one below. Except we're using a 1.5" diameter wooden dowel instead of PVC for the crossbars, plus heavy black, round-weave nylon rope.

We need to figure out the best way to keep the two crossbars from slipping down (it'd be best if we could adjust them up as time goes on). Knots are the obvious easy choice, but Hubby pointed out that it'd be hard to get them in the same spot on each side.

What are the other options that would be strongest and safest for a curious kidlet?

http://www.bipgear.com/store/images/categories/Platform%20Swing-Medium.jpg

 

[bobinks2]

I would probably try tying a 'clove hitch' knot in the rope around the wooden dowel. After time, you should be able to untie and adjust the knot.

You can google clove hitch to see one.

 

[SweetErika]

I would probably try tying a 'clove hitch' knot in the rope around the wooden dowel. After time, you should be able to untie and adjust the knot.

You can google clove hitch to see one.

I forgot to mention the rope is like 3/4" and smooth, plus it's an indoor swing so we're only going to put it up as we use it. Because of those factors, Hubby said clove hitches might be an issue (he's a former Scout, the son of a boat guy, and very familiar with the more common knots).

So, it's something we can try out, but having other options would be great.

 

[chipcarver]

There are cable clamps that you could use although I am not sure if they come in a big enough size.
Personally I would slowly walk the hardware store aisles that contain rope products, fence cable, and wire.
Your husband seems pretty handy and knowledgeable from previous posts so a slow careful walk should spark some ideas.

 

[pplwatching]

Your hubby is right. Clove hitches are prone to slipping when tied near the end of the rope, especially with nylon. Plus you have to check them every time you use them - something your kiddo is not likely to do.

This is actually easier than it seems, but you will need to use a jig or a drill press to drill your holes in (preferrably) hardwood dowels. You need to drill your holes so the rope can slip through with a little effort when there's no load, but such that they create enough friction to hold the rod in place on the rope when there's weight on the platform. To accomplish this, you need to bind the rope when it's taught. Much like a Chinese finger puzzle.

Choose a drill bit that is the same diameter as your rope, or only slightly larger. Set the drill press to just a shade over 3/4 inch depth (1/2 of your dowel rod) and adjust the platform to a 5 or 10 degree pitch. Drill half way into the dowel rod. Turn the dowl rod over and drill the other half of the hole. This creates a V shaped hole. The apex (vertex) in the hole will bind against the rope when it is carrying weight (the platform and/or the child). When the rope is slack you can move the dowel rod. The rope will pass over the apex and through the hole, allowing you to adjust it as necessary.

Do not use a rope (or drill bit) that is too large. The bound rope will exert pressure against the rod. Removing too much material from the dowel rod will weaken the rod and the pressure exerted by the rope may crack it. Then again, your kid isn't as heavy as a full grown adult and the force shouldn't be all that excessive.

Good luck.

Edited to add that if you want, you can make the top 1/2 of the hole at a steeper incline to better match the slope of the rope. That looks like what they've done in the picture. They probably have a plastic insert with an apex in it.

 

[NippleMuncher]

I can think of a few things.

1 - Drill holes in the dowel to accept the rope. Make the hole as small as possible and still get the rope through, the tighter the better, but you have to be able to slide the rope/dowel to the desired location. Once you've got it you can cross drill and pin the rope with several nails or screws.

2 - An alternative to the nails in the above description would be to drill the hole for the rope and split the end of the dowel from the rope hole to the end of the dowel. Next drill a perpendicular hole between the rope hole and the end of the dowel for a 1/4" machine screw. Place the dowel on the rope at the desired location and tighten the bolt to pinch the rope. The round head of the machine screw and cap nut will prevent Munchkin from injury.

3 - Put Hubby's boy scout skills to the test. Drill hole and install rope as described above, then use a length of leather or twine to lash the dowel into place.

4 - Instead of running the rope through the dowel, what about attaching it to the ends? Drill a 1/4" - 3/8" deep hole in the ends of the dowel that are the same diameter as the rope. Cut a piece of 1/2" pvc pipe 3/4" long, then slice it lengthwise into thirds. Drill a hole slightly larger than a #10 sheetmetal screw through the pieces of pvc to make cove washers. Use a #10 screw that is at least twice as long as the diameter of the rope. Place the rope over the hole in the end of the dowel, place the pvc washer over the rope, and install the screw until it is pinching the rope tightly into the end of the dowel. I would take this one step further and channel the ends of the dowel around the rope to prevent the dowel from being able to twist. I can explain how to do this should this method be an option.

5 - If you've got a good Tru-Value or Ace Hardware near you, they should have a plethora of clamps and hardware options to choose from. Don't be afraid to walk throughout the store looking for any item that could be purposed for the job. The main problem with clamps is that they can easily snag, scratch, pinch or damage the munchkin if he gets a hold of them.

 

[PhilGarlic]

two holes

drill two holes next to each other, if rope is coming from the bottom pass rope through the top of first hole, then pass up through the next hole, easy to adjust and will tighten on itself when weight applied. If you are worried about it slipping tie a round turn knot around the dowel before passing it through second hole. Very easy to adjust when necessary.

Just out of interest, what will you hang it from? you said it was for indoor use.

Thinking about this, you only need one hole, pass rope through the hole, take one round turn around the dowel one around the standing part of the rope and there you go. Easy, no screws or nails or anything to come away.

 

[SweetErika]

Phil, we'll be hanging it from two eye bolts in studs. The munchkin is only 35 pounds, so two should distribute the weight nicely, even as he grows. We already have one bolt in the ceiling from suspending a little circus tent. Because the little guy is only 2 and an impulsive risktaker, he definitely won't be using the swing (which is to help his sensory disorder issues, BTW) without supervision. We'll probably use it for about 20 minutes at a time, then take it down between uses so he can't get into trouble on his own.

Anyway, thanks for the speedy replies, and I'll have Hubby look at all of your suggestions! If we can't thread something through the rope, lashing or figuring out some kind of knot to tie around the rope under the bar with leather lacing (I have some left over from making a flogger ) that wouldn't slip down the rope, or threading the rope as Phil suggested will likely be our best options. We don't have access to a drill press or anything, so fancy holes won't work. I suppose another option might be to ditch the dowel and thread both ends through a length of PVC in opposite directions, perhaps with hole drilled in endcaps so there won't be any sharp edges.

 

[pplwatching]

Another simple approach might be just to chamfer or counter sink one side of the hole slightly, put a small whipping on the rope at the position that you want the bars to rest, and pull the whipping snugly into the hole. When you want to move the bar you can cut the whipping and make a new one at the desired position.

http://www.ropeworks.biz/reader/whipping.pdf

Good luck with the project. Also, don't forget to put non slip pads on your platform. The sticky pads made for showers should work nicely.

PS FWIW You can accomplish the angled hole with a vise and a steady hand if you don't have a press. Home/hobby presses are relatively cheap and woodworking is a common hobby, so a friend might have one too. I'd also be happy to drill a couple bars with mine and send them to you in a poster tube.

 

[SweetErika]

Yeah, I was thinking about whipping under the bars this morning.

We carpeted the top of the platform for comfort and grip. I can add a pad if necessary, but the swing at the occupational therapist is carpeted, so I think it'll be fine. We slit pipe covers down one side and put them around the edges as "bumpers."

And that's as far as we've gotten. Hopefully we can finish it today, since Monkey is with my mom.

 

[glynndah]

Why not install a series of crossbars on the sides with a knot under each one?

 

[SweetErika]

So, we finished it last night and ended up using Phil's threading solution with an extra twist and loop for now. I may still do the whipping or something, but the current setup allows us a lot of flexibility while we figure out where the bars are best placed.

Thanks again for your ideas, everyone! Our little guy is super thrilled with his new toy/therapy tool!

 

[PhilGarlic]

is

So, we finished it last night and ended up using Phil's threading solution with an extra twist and loop for now. I may still do the whipping or something, but the current setup allows us a lot of flexibility while we figure out where the bars are best placed.

Thanks again for your ideas, everyone! Our little guy is super thrilled with his new toy/therapy tool!

Is there a prize for me to collect

Hope your litlun has great fun.

 

[SweetErika]

Is there a prize for me to collect

Hope your litlun has great fun.

What, like a booby prize?

He's having fun, and it definitely helps calm him down so he can focus better and relax before sleeping. Thus far, it's one of very few things we've found that works so quickly on easing his sensory disorder, so it's a huge blessing for all of us!

 

[NippleMuncher]

What, like a booby prize?

Did someone say ... prize!

 

[PhilGarlic]

What, like a booby prize?

He's having fun, and it definitely helps calm him down so he can focus better and relax before sleeping. Thus far, it's one of very few things we've found that works so quickly on easing his sensory disorder, so it's a huge blessing for all of us!

Your just teasing

Glad it's having the desired effect.

 

[NippleMuncher]

Your just teasing

Glad it's having the desired effect.

WHAT?!?!?!?! No prize??!?!?!

 

[PhilGarlic]

if

WHAT?!?!?!?! No prize??!?!?!

And if there was a prize I would be happy to share !!!!!