Dowling rod wood type for monkey bars?

[AlanB1976]

Hi all

I was hoping to get some advice on the use of dowling rod as monkey bars for my kids climbing frame (outside). I say monkey bars but the kids will also be climbing on top, which is why I’m looking to fix the bars mid way between the sides, not on top which would be much easier, as it would add a bit of a safety risk of tripping/hooking on one while on top. I also need them to be very secure as one failing while hanging on is not an issue, but potentially fatal if failing while a kid is standing on the top.

So, what I was thinking was to get 35mm diameter rod and fix to sides with coach screws. The first query I have is what wood would be best? Obviously, I need something hard enough to support the weight of kids. I read Ash would be good being a bit more “springy and forgiving”. I don’t know much on wood so any advice would be good.
Then, as far as fixing them, would coach screws be best or should I be considering another means? I considered fixing by base plates but since there are swing attachments on the one side, they won’t fit nicely. I also considered drilling in a bit to the sides so the rods fit inside but I was concerned that would weaken the sides and it would be a considerably additional amount of effort for me to install just in the way I have to attach this to the climbing frame, and the fact that one piece of wood is slightly warped which would mean it wouldn’t align consistently and each bar would have to be custom fit (not majorly warped but enough to make it a bit of a pain).

Any advice?

Thanks
Alan

 

[endecotp]

I think I’d use a hole saw to make suitable holes in the side timbers and thread the bars through. Or fit a suitable timber alongside it, and make the holes in that.

Have you considered metal bars? How long will they be?

 

[AlanB1976]

Thanks for the reply. I was hoping to get away without having to use different wood. I may try just drilling about 2cm depth hole for the rod and use coach screws. It will be a real pain though with the wood not being completely straight. Yeah, yeah, I know, I should use something else. It's just that this wood matches perfectly (look and size) to the original climbing frame and I can't find the same size here.
I'm not set on the dowling rod, it would just be easier to secure with coach screws, cheaper and may look nicer being wood. Powder coated bars would also look nice but is pricey and I would probably have to look at more than 2cm holes due to not being able to secure with screws, which worries me that I'm weakening the wood a bit much (70x70x2400mm).
What places are recommended for treated timber? Maybe I can find something better. I've looked at wickes, B&Q and my local timber supplier? I know pretty little on types/suppliers of timber.
Thanks
Alan

 

[big-all]

to be honest i can't give any help without having a good idea off the design and spans concerned
35mm would be quite weak in my opinion and would be reluctant to use over greater than say 300mm unsupported without trial and error using my 18 stone dead weight to replicate the load off 2 hyperactive 8-12 year olds

 

[JohnD]

Aluminium tube might be more suitable. It won't split or rot and its strength can be confidently predicted.

I used to know someone who used a lot of ex-gym wood. Parallell bars and similar items are discarded as soon as they get a chip, crack or split, because they might injure the users with splinters. I forget what the timber was. Something very straight-grained and knot-free.

 

[AlanB1976]

Thanks for the advice. I've forked out the additional cash to go for aluminium tube (1 1/4"). Now the issue of fixing them since I can't just attach using coach screws. I'll post that question separately as the title here is dealing with dowling rod. Thanks again for the assistance.

 

[JohnD]

Drill holes that are a tight fit, and poke it in. You might use a hammer and a biodegrable lube, such as lard.

 

[AlanB1976]

Thanks.
Do you think a 1" (25mm) hole in each side will be sufficient? Aluminium tube is 1-1/4". If more is needed, I may have to get additional timber as the one side that exists is only 70x70mm and I'm worried about weakening it. Was thinking of just using wood glue to secure.

 

[JohnD]

I think you'll need a hole saw, and some trial holes as they may not be precise in size.

Glue might also work as a lube while it's wet.

 

[AlanB1976]

I got a hole saw, although the closest size is 32mm where the tube is basically 31.75mm, so may not be a tight fit (which I was hoping the wood glue would rectify). Else I can drill 30mm holes and use my dremel to expand..... but that now will be a pain to do on every hole. What depth of hole would you recommend?

 

[big-all]

assuming the timber is at least 40mm thick
drill your holes 30mm deep leave the pegs loose
and just have somthing tying the rails together every 600mm or so

 

[AlanB1976]

Really, as little as 10mm is sufficient for the rails to still be sturdy? (I'm not challenging, just shocked that so little is fine)
The timber is 70x70mm so the 30mm won't be a problem then.
If the bars are loose, wouldn't they rotate and hence not be too good as monkey bars?

 

[AlanB1976]

p.s. I have posted another post asking this question as the title here is now misleading (not using downling rods anymore), but I don't mind the answers coming here. Any help is greatly appreciated

 

[big-all]

10mm is fine but iff the treads are loose i would put a large penny washer the size off the tube as cut pipe/profile can make a quite efficient "saw" if left with a coarse cut edge
if the monkey bar "bridge" is a bit springy then a say 45% support bracket back to an upright at say 1/5 and 4/5ths will reduce the unsupported span by around 40%

 

[AlanB1976]

thanks