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Bolt Plates

Gzubi

20-May-2007
11:38:27 AM

Is it better to get 45 or 90 degree bolt plates? Do they have a different purpose?

TLockwood

20-May-2007
12:07:17 PM

Speaking of bolt plates, are there different size bolt plates? Because I've noticed some of the new machine carrot bolts being put in the gramps dont take half of the bolt plates I own.

paul

20-May-2007
12:37:26 PM

The head size on imperial bolts vary, on metric ones they are generally pretty standard, for example a 10mm bolt will normally have a 17mm head, some bolt plates may be designed with imperial bolts in mind which often have smaller heads.

Most new bolt plates acomodate larger head sizes, but i have hat trouble with SRT brand ones in the past.

On 20/05/2007 TLockwood wrote:
>Speaking of bolt plates, are there different size bolt plates? Because
>I've noticed some of the new machine carrot bolts being put in the gramps
>dont take half of the bolt plates I own.
>

jgoding

20-May-2007
6:11:28 PM

Personally I like the 45 degree ones.

FYI Climbinganchors.com sell a new style one which is perhaps a little stronger than the normal PFH and RP brands generally available in most climbing stores.

I heard some talk about titanium ones recently, but the cost per unit and minimum run quantity of 1000 units means that the people considering this first run will need some convincing that people will buy them. The spec could be for much stronger bolt plates.

I also have found that the PHF ones are slightly smaller in their gap size than the RP ones, and therefore tend to get less issues with fiddling them onto bolts, particuarly metric (M10) ones which have not had their heads filed down. Basically filing down the head size is a good thing (on the hex end of the bolt) so that the bolt plate can go on without too much drama.


BigMike

20-May-2007
9:55:38 PM

On 20/05/2007 jgoding wrote:

>FYI Climbinganchors.com sell a new style one which is perhaps a little
>stronger than the normal PFH and RP brands generally available in most
>climbing stores.

Has a bolt plate ever been known to fail?


mousey

20-May-2007
10:23:32 PM

dunno but ive bent 1 or 2 up pretty badly, not even with huge or really hard falls. i normally carry pfh 90's but have a few RP 45s in case the 90s are too tight to get on there. by the way, PFH make a stronger version of their bolt plates for rigging & stuff... just a few dollars more i think


Chuck Norris

20-May-2007
11:10:39 PM

does it matter what plates you buy? because aren't bolt plates sort of like "left socks" and as long as you
make a donation to the pool then you are granted access...sometimes I've owned lots sometimes none,
but I'm sure I've only bought one or two.

my answer to your actual question is that in certain situations different angles can get over certain bolts
better. As you can never predict these situations buy a couple of each...but bear in mind my point above
as you will only have the plates you buy in your possession for only a week (don't worry you'll have
someone else's)

drdeviousii

21-May-2007
12:52:58 AM

On 20/05/2007 mousey wrote:
>dunno but ive bent 1 or 2 up pretty badly, not even with huge or really
>hard falls. i normally carry pfh 90's but have a few RP 45s in case the
>90s are too tight to get on there. by the way, PFH make a stronger version
>of their bolt plates for rigging & stuff... just a few dollars more i think

Don't be too worried about bolts plates bending out of shape - just don't bend them back again. They will 'stretch' up to 50% before failing.

Gzubi

21-May-2007
10:52:46 AM

Someone was telling me that it is better to use 45s for runners. However, 90s are better suited to top anchors. Is this right?


muki

21-May-2007
11:37:02 AM

They all perform equally well in any situation!
The only difference that I can distinguish is that a 90 degree plate is best used on a roof bolt, as you will
bend a 45 to 90 if you fall, so why not use the one thats designed for that particular type of loading?
the 90!


anthonyk

21-May-2007
11:58:22 AM

On 20/05/2007 jgoding wrote:
>I heard some talk about titanium ones recently, but the cost per unit
>and minimum run quantity of 1000 units means that the people considering
>this first run will need some convincing that people will buy them. The
>spec could be for much stronger bolt plates.

hang on, if the bolt is made from stainless steel and the bolt plate is made with titanium, would it cut into the bolt?

gfdonc

21-May-2007
12:07:44 PM

On 21/05/2007 anthonyk wrote:
>hang on, if the bolt is made from stainless steel and the bolt plate is
>made with titanium, would it cut into the bolt?

Not sure why you would even think that.
Some better-informed metallurgist is invited to respond, but from a loading point of view, why would you think 10kN would be enough to slice into metal?
Bear in mind Ti is roughly the same strength as steel per volume, so the brackets would either be lighter or stronger, but not thinner. As Joe indicated, the idea might be to make nice thick Ti brackets that looked (and were) much beefier than steel, but without a weight penalty.


anthonyk

21-May-2007
12:11:00 PM

On 21/05/2007 gfdonc wrote:
>Not sure why you would even think that.
>Some better-informed metallurgist is invited to respond, but from a loading
>point of view, why would you think 10kN would be enough to slice into metal?
>Bear in mind Ti is roughly the same strength as steel per volume, so the
>brackets would either be lighter or stronger, but not thinner. As Joe

i don't know much about metals, but i thought it might be something like hardness where one will cut into the other depending on the relative strength (hardness?) of the materials. but was just asking, i don't know anything about what happens with metals


muki

21-May-2007
12:20:10 PM

Sure, but the forces you are talking about would proly kill the climber as well,
as both metals are extreemly hard.
Aluminium gets little nicks on the inside apex cos it's soft as metals go, then comes under large forces
when placed on a stainless steel hanger plate, and is hard as metals go.


AlanD

21-May-2007
12:52:16 PM

On 21/05/2007 gfdonc wrote:
>On 21/05/2007 anthonyk wrote:
>>hang on, if the bolt is made from stainless steel and the bolt plate
>is
>>made with titanium, would it cut into the bolt?
>
>Not sure why you would even think that.
>Some better-informed metallurgist is invited to respond, but from a loading
>point of view, why would you think 10kN would be enough to slice into metal?
>Bear in mind Ti is roughly the same strength as steel per volume, so the
>brackets would either be lighter or stronger, but not thinner. As Joe
>indicated, the idea might be to make nice thick Ti brackets that looked
>(and were) much beefier than steel, but without a weight penalty.
>
Metallurgist here ;)

The relative hardness is the real issue, titanium Ti.6Al.4V ( a common Ti Alloy) is about twice as hard as say 316 stainless or 3 times 304 stainless. In a wear situation, hardness is an extremely important factor. While the loads involved are probably insufficient to chop the bolt off in a single event, the continuous motion of the bolt plate relative to the bolt is going to cause the wear of the bolt, thus reducing the life expectancy of the bolt.


anthonyk

21-May-2007
1:18:38 PM

On 21/05/2007 bomber pro wrote:
>Sure, but the forces you are talking about would proly kill the climber
>as well,
>as both metals are extreemly hard.
>Aluminium gets little nicks on the inside apex cos it's soft as metals
>go, then comes under large forces
>when placed on a stainless steel hanger plate, and is hard as metals go.

yes i was talking about long term wear not a single fall. it wouldn't be very good if some hangers were slowly eating away at the bolts on popular climbs.

sort of like how a backpack can be made of really strong materials, but if you've got a joint between areas of different flex or something it gets worn down over time, even with small forces like holding up a fraction of the load on someones back with a bit of back and forth movement.

i'd even suspect that if there's different hardness material it can cause damage to the bolt simply from the bolt plate getting rotated around the bolt on a regular basis, it wouldn't have to be taking falls to get worn.


muki

21-May-2007
1:40:15 PM

Sure I agree with that but, It would still take a long time, and not every bolt is the crux bolt that gets
hammered on a regular basis, but just a bolt that protects a runout section of less than crux style
climbing! so the bolt that gets the falls could be a camo fixed hanger and not have to deal with the
titanuim hanger plates.
But due to the production run costs, it might never happen, look back at the T-shirt printing thing and see
how hard it is to get any type of financial support from climbers in general, wether it be funds for SCV or
a lousy T-shirt, most climbers like to think that somebody else will proly donate some cash so they won't
bother, look in your hearts people you know who you are!


AlanD

21-May-2007
2:08:14 PM

Usually in the material selection process when wear is an issue, you choose the a softer material for the one most easily replaced, in this case the bolt plates if they aren't fixed. For fixed bolt plates, weight is a non issue, so choosing a similar alloy is ideal.

If weight is an issue for a non-fixed bolt plate, I'd be starting to look at some of the high strength* wought aluminium alloys (possibly one of the 7000 series), rather than looking at titanium.
* Might be issues wear and long term durability.

Ronny

21-May-2007
3:19:33 PM

I saw something like this a while back. I replaced the first bolt on 'Peregrin' at Norton Summit (probably the most fallen on bolt in South Australia - but that's not saying much I guess). It was an expansion bolt, but the plate had been loose for quite a while. The plate always rotated as people fell onto it, and when I ripped it out the bolt had worn through about 3mm or so (10mm bolt). The bolt plate was quite worn as well - but the bolt had certainly taken a hammering.

So I guess it is possible for this sort of wear to occur. Not sure if it would be all that common though.


anthonyk

21-May-2007
4:22:01 PM

On 21/05/2007 AlanD wrote:
>If weight is an issue for a non-fixed bolt plate, I'd be starting to look
>at some of the high strength* wought aluminium alloys (possibly one of
>the 7000 series), rather than looking at titanium.
>* Might be issues wear and long term durability.

i guess in general its probably good that we carry around the re-usable and easily replaced stuff, ie bolt plates, quickdraws? etc, because it has to be made lighter so likely ends up slightly softer as well. if we were using the same type of metal for clipping that we use for the bolts the fixed stuff would probably wear out a whole lot faster (no?).

There are 37 messages in this topic.