Material selection

**imdying** · 29th July 2009, 11:55

If you were getting some parts made for a bike, would these materials be suitable?

Triple clamps - 6061 aluminum
Caliper mounts (adaptor bracket type objects) - 6061 aluminum
Disc adaptor (PCD changer, 5mm thick, 2 sets of holes) - 5083 aluminum
Fork lower - 6061 T651 aluminum
Axle spacers - 6261 T6 aluminum

Construction is a mixture of water jet cutting and basic machine work.

I'm not an engineer's arsehole, I have no idea, just hoping someone in the trade would have some comments.

**Brian d marge** · 29th July 2009, 12:54

Triple clamps - 6061 aluminium
Calliper mounts (adaptor bracket type objects) - 6061 aluminium
Disc adaptor (PCD changer, 5mm thick, 2 sets of holes) - 5083 aluminium
Fork lower - 6061 T651 aluminium
Axle spacers - 6261 T6 aluminium

with out checking myself . just sat down with coffee, all seems ok ( touch over kill but its not like its expensive )

I would have to check the 5083, Someone else may now better than me the reason It may get warm on or have repeated heat cycles , and I would be worried about cracking ..

My Enfield con-rod is LM2 , ie cheese and a poor quality cheese at that , its done 17 000 km

If some one doesn't come up with a more comprehensive reply , post again and I ll double check for you

Stephen

**imdying** · 29th July 2009, 14:13

Thanks very much for the reply.

The disc is a 160mm x 2mm disc, so very light duty stuff (the adapator probably has twice the mass of the disc).

How about the axle spacers? Any issues with using aluminium on a part that I nomally see in steel? The size is approximately 10mm long, 16mm OD, 10mm ID, with one end with a 2mm recess, 14mm OD, to suit the bearing inner race. Basically that leaves a 2mm thick portion against the race, do you think that the 6261 will be suitable (i.e. not crush if tightened adequately).

**Brian d marge** · 29th July 2009, 16:00

Originally Posted by imdying

Thanks very much for the reply.

The disc is a 160mm x 2mm disc, so very light duty stuff (the adapator probably has twice the mass of the disc).

How about the axle spacers? Any issues with using aluminium on a part that I nomally see in steel? The size is approximately 10mm long, 16mm OD, 10mm ID, with one end with a 2mm recess, 14mm OD, to suit the bearing inner race. Basically that leaves a 2mm thick portion against the race, do you think that the 6261 will be suitable (i.e. not crush if tightened adequately).

guessing from the id of the spacer the spacer is a front wheel spacer on a small bike and the spindle is od 10mm 1.25 thread ?

so we can get a force from that, and from that see the crush, I can run it through calculix if you want,

assuming a good bearing surface it should be ok ,,, at a guess. !

Stephen

does it look like this? you made it out of steel then left it in the garden !

Stephen

i have a bit of time, tomorrow if you post sketches, if you are worried, from what I understand it should be ok !

**imdying** · 29th July 2009, 16:31

Yup, just like that! And yes, I'm planning on making an axles with 10x1.25mm thread. It's really the only part I'm concerned about, whether to make it from steel or 6261 T6.

**Brian d marge** · 29th July 2009, 16:57

Originally Posted by imdying

Yup, just like that! And yes, I'm planning on making an axles with 10x1.25mm thread. It's really the only part I'm concerned about, whether to make it from steel or 6261 T6.

if you can give me an idea of the other parts ( or should I just run with this ! )

I think i understand , but its better to be sure

Do you know the torque on the nut od the axil? or hand tight plus 180?

Steel is a nice material you know ... not so heavy

Stephen

**Robert Taylor** · 29th July 2009, 22:11

Originally Posted by Brian d'marge

Triple clamps - 6061 aluminium
Calliper mounts (adaptor bracket type objects) - 6061 aluminium
Disc adaptor (PCD changer, 5mm thick, 2 sets of holes) - 5083 aluminium
Fork lower - 6061 T651 aluminium
Axle spacers - 6261 T6 aluminium

with out checking myself . just sat down with coffee, all seems ok ( touch over kill but its not like its expensive )

I would have to check the 5083, Someone else may now better than me the reason It may get warm on or have repeated heat cycles , and I would be worried about cracking ..

My Enfield con-rod is LM2 , ie cheese and a poor quality cheese at that , its done 17 000 km

If some one doesn't come up with a more comprehensive reply , post again and I ll double check for you

Stephen

Triple clamps and fork lower 7075T6

**98tls** · 29th July 2009, 22:25

Originally Posted by imdying

If you were getting some parts made for a bike, would these materials be suitable?

Triple clamps - 6061 aluminum
Caliper mounts (adaptor bracket type objects) - 6061 aluminum
Disc adaptor (PCD changer, 5mm thick, 2 sets of holes) - 5083 aluminum
Fork lower - 6061 T651 aluminum
Axle spacers - 6261 T6 aluminum

Construction is a mixture of water jet cutting and basic machine work.

I'm not an engineer's arsehole, I have no idea, just hoping someone in the trade would have some comments.

Les might be the bloke to talk to mate.Besides that fwiw your making me jealous.

**Brian d marge** · 30th July 2009, 01:32

Originally Posted by Robert Taylor

Triple clamps and fork lower 7075T6

eeeuuww that's a statement, statements worry me... 75 is good but it does have limitations, ( in this case not a worry )

Stephen

**imdying** · 30th July 2009, 08:32

Originally Posted by Brian d'marge

if you can give me an idea of the other parts ( or should I just run with this ! )

I think i understand , but its better to be sure

Do you know the torque on the nut od the axil? or hand tight plus 180?

Steel is a nice material you know ... not so heavy

Stephen

Yeah, it's all teeny tiny stuff, steel wouldn't make a big difference on those spacers! If you let me know your email address, I could send you a blueprint... I wouldn't mind knowing what the most likely part to break first is

Originally Posted by 98tls

Les might be the bloke to talk to mate.Besides that fwiw your making me jealous.

Don't worry, it's not for my SV, if I didn't have so many projects needing attention I'd probably just let RT sort all of that out rather than making my own... although, a custom top triple would be a nice place to start.

**Brian d marge** · 30th July 2009, 12:58

Originally Posted by imdying

Yeah, it's all teeny tiny stuff, steel wouldn't make a big difference on those spacers! If you let me know your email address, I could send you a blueprint... I wouldn't mind knowing what the most likely part to break first is

Don't worry, it's not for my SV, if I didn't have so many projects needing attention I'd probably just let RT sort all of that out rather than making my own... although, a custom top triple would be a nice place to start.

477.racing @gmail.com

I am in the office till at least September ,,its like an oven outside. Just post up a sketch, and we can look at the stresses

now my meshing ability isn't so hot , so sometimes complicated parts are a pain to mesh , but other than that ,,feel free

Stephen

**imdying** · 30th July 2009, 13:35

Originally Posted by Brian d'marge

477.racing @gmail.com

I am in the office till at least September ,,its like an oven outside. Just post up a sketch, and we can look at the stresses

now my meshing ability isn't so hot , so sometimes complicated parts are a pain to mesh , but other than that ,,feel free

Stephen

Cool, I'll send it through.

Nothing complicated about this, it's all very simple stuff

**Brian d marge** · 30th July 2009, 16:36

Originally Posted by imdying

Cool, I'll send it through.

Nothing complicated about this, it's all very simple stuff

using a yield of 70Mpa and a torque of 4kg.m ( from my CR250)

which really are waaay over the top and assuming I've got my units right !

u should be OK with your selection, just pay attention to the radii of spacer on to bearing , this radii can be found in any bearing book , just avoids stress raisers

Stephen