Mix half rope and triple rated rope

Assuming same diameter, can you use a triple rated rope and a half rope together? 

Yes

Depends on the application, but they don’t strictly need to be the same diameter either.

Cron wrote:

Depends on the application, but they don’t strictly need to be the same diameter either.

I would think that dynamic elongation and/or impact force matter more than diameter, if anything matters.

It’s unlikely that anything matters. 

Hijacking this : I have an 8.8 that I use for sport and alpine. I also do a lot of trad and ice climbing and have been considering double ropes for a long time but never taken the plunge. Should I get a little half rope and use doubles for all but redpointing and chill alpine? Anybody doing this? Would using doubles for trad (I do sometimes whip when trad climbing) would preserve my skinny single at all?

Gaston on aid

People have been using single ropes with half rope technique since before there were half ropes. Not the same as twin ropes.

I certainly know there's no reason not to do this, except buying another rope. I suppose climbing with half ropes would generally save some wear and tear because you can lessen drag more effectively

Daniel,

off-topic but what is that in your profile pic? Looks sick

Martin, it's La Fiamma in switzerland: https://www.mountainproject.com/route/109341545/la-fiamma

Cron wrote:

Depends on the application, but they don’t strictly need to be the same diameter either.

I thought that both half ropes should not be of greatly different diameter though I don't know of any proof via testing. I think its known that if only one half rope is weighted in a leader fall the breaking force is reduced and it might make sense that a thinner rope would be even harder to grip with a larger diameter rope next to it.

i shore wrote:

I thought that both half ropes should not be of greatly different diameter though I don't know of any proof via testing. I think its known that if only one half rope is weighted in a leader fall the breaking force is reduced and it might make sense that a thinner rope would be even harder to grip with a larger diameter rope next to it.

No definitive testing but when I tried this at home  it was more difficult to brake when the skinnier of the two ropes was the one  being loaded. .2-.3mm difference was not too noticeable but more than that seemed sketchy. Again, testing method was rudimentary. With same diameter as OP asked half rope technique should be good, twin technique not recommended.       Edit: might want consider abd like micro jul

Jared Chrysostom wrote:

It’s unlikely that anything matters. 

so say we all, in the face of such grotesqueries as man has wrought on earth