[Closed] Does this look like a cracked frame to you?

Doesn't look to good to me!

Hmmm. Not having a good day. Can I not link to Picassa?

I think it's definitely cracked 😉

Can you see the image? I can't!

I had to download in a new tab...looks to be in a place where you'd 'expect' a crack too.

Ah, I see. Thanks for the feedback. Gutted... 2nd hand frame 🙁

cant see a pic 🙁

[img] [/img]

ooh..take the paint back to be sure. You never know

Right click and open in new tab I think is the best way. Sorry. Not sure why it's not linking

[img] [/img]

ouch.

bin it

get it fixed and keep it for commuting/pootling/niche/retro/touring/owt else boring......

As someone else has said scratch/remove the paint off in the area for a better look. It doesn't look good but might just be paint.

It's a DH frame 🙁

It has just been resprayed...

[u]Was[/u] a DH frame...

What frame is it?

If the paint is fresh it's potentially more likely to be just paint for me (unless the seller did it of course), different type of pain etc. Take the paint off and look underneath.

Crack

Oh yes. Thats cracked.

Paint doesn't crack for no reason.

[url= http://www.rocol.com/corp/index.php?option=com_content&view=article&id=409&Itemid=428 ]get some of this[/url]
`tis what we use on vessels and pipework

Drill a hole either end and get a local engineering works to weld. Preferably a sheet metal works used to working with thin materials.
Still a risk that it will crack again tho 🙄

I wouldn't be so sure its cracked. Too many armchair critics and its very hard to tell from that picture. If i were you I would carefully remove the paint around the weld and check if its just the way the paint has dried.

What's the best way to remove the paint guys?

Either with a screw driver/sharp blade if its a powdercoat (which it looks to be) which will likely flake off easily (especially round a weld).

If this doesnt work dab a little bit of nitromors on the area.

Where is the crack George? Can't work it out. Give Orange a call before you start messing about with the paint, they might prefer to inspect and sort it themselves given that it's a prototype, they will likely be interest in where/how it's failed.

Thanks Joe. I live in hope...

Downtube Rocky. Gusset that joins to headtube...

Have emailed them and not gonna touch it till I hear back...

If it helps,I had a Diamondback WCF4.0 back in 1997, it developed a crack in the paint on the down tube, all the way around the tube. I rode it for about 18 months before I realised that it was a crack in the bond between the chromoloy lugs and the carbon fibre tubes. A rock hit the down tube and knocked a lump of filler out and I didn't ride it again, but it worked no problems with effectively no down tube at all.

In short, it'll be fine! 🙂

As someone else has said scratch/remove the paint off in the area for a better look. It doesn't look good but might just be paint.

While I'd like to be optimistic....given the location (next to a weld, HAZ etc) I'd put my house on it being a crack. Hell it IS a crack. 🙁

WHAT FRAME IS IT???

It's an Orange 225 prototype DH frame, as raced by Ben Cathro last year.

classic gusset+big gobby weld = crack(possibly)
Gussets have a tendency of moving any stress to another area. If this is badly designed/placed etc then failure will occur. Some people think they are for strengthening an area but if badly executed then all they due is move the problem. Alloy is especially prone to thinning at the edge of a weld and on a thin tube it can create problems.
Have you been on a DH forum and asked other owners of this brand/model?

it's a crack.

it's cracked.

It's an Orange 225 prototype DH frame, as raced by Ben Cathro last year.

LOL how many words in that sentence can you have that all point to it being cracked. Let's see 'orange' 'prototype' 'dh' 'raced' and 'by Ben Cathrow'a,

their dead dave, dave their dead, dead dave , dave they are all dead. Yep its dead 🙁

Probably cracked, but, slight flex can crack paint, and your new paint could be badly applied or could have shrunk back, or they might have stupidly painted it with cellulose which cracks if you look at it funny. Cut the paint back and have a look, it's not like you've got anything to lose.

Looks like a crack to me, on a regular basis when frames are repsrayed they crack as the aluminium is slightly altered.

Google frame cracking after respray, it hapens a lot more often with powder coated frames as they're baked in the over at higher temps.

Good luck!

[s]Probably[/s] cracked

hth.

Can not find anything about cracking after respray. or powder coating. How exactly does painting change aluminium or steel to make it crack?

The pic definitely is cracked though.

Can be welded by sheet metal fabricator, shouldn't cost to much and if done properly is no more likely to crack than when it was new.

Bit of helicopter tape round it and you'll be fine 😉

How exactly does painting change aluminium or steel to make it crack?

raw aluminium is very soft and weak. stuff like copper is added in small amounts to make it harder/stronger - the alloy strengthening effect is 'activated' by heat. typically at around 200degrees (or more) for a few hours.

the hotter the process, the harder the alloy becomes.

the longer the process goes on for, the harder/stronger the alloy becomes.

unfortunately, the harder/stronger the aluminium becomes, the more brittle it becomes - it's more likely to crack.

(hard = brittle = bad)

i don't know enough about powder coating to say if it's hot enough or lasts long enough to have a significant effect on the properties of the alloy - but i guess it's a concern...

(i'd want to do my homework before i'd tell anyone it was definitely ok)

alloy strengthening effect is 'activated' by heat

No its not. Alloy is alloy (subject to its specific composition, and basic characteristics of course)

Heat treating allows the re-alignment of a metals crystalline structure, and can alter the size and shape of those crystals. The duration of the bake can also make a difference.

You can heat treat a pure element (iron for example) and change its characteristics in the same manner.

Low temperature powder coating that should be used for tempered aluminium is between 100 and 120 usually - this won't affect the alloy in any way. You need a bit more to re-temper aluminium last time I made enquiries of a frame manufacturer about this, I was told 175 celcius max.

So, my frame was put in the wrong oven by the powder coaters and taken to 400 degrees. It didn't come out superhard by the way, it lost all its temper, and was malleable as roofing lead.

No its not. Alloy is alloy (subject to its specific composition, and basic characteristics of course)

TBH as materials engineer with 15 years experience of heat treatment of steels and Al alloys I though Awhiles description was pretty good explanation to the layman.

I think Awhiles was trying to simplify how he explained typical heat treatment of a bike Al alloy, which would be something like a 6061, a precipitation hardening alloy, and the heat does "activate"the strengthening mechanism. It's known as age hardening, or ageing. A major problem in Al alloys is over ageing where they are heat treated for too long. This is what may happen if you powder coat your frame.

I would always advise against powder coating of Al alloys unless you are very famailiar with how it was heat treated and how accurate the temp control of the powder oven is.

Science officers tale is not surprsing at all as powder coating is often not subject to as tight controls as heat treatement.