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Crasherfromwayback
7th October 2012, 16:15
Long story short. I need a clutch cover and waterpump housing made for a bike that they're not avail for. Is there any foundry in NZ you know of that'd do one offs like that in magnesium I can trust to do it right? Alloy if need be.

Ta.

Pete

tigertim20
7th October 2012, 16:21
hayd3n worked at the foundry down here a few years ago, he may know more details around what they can or cant do.

what are your dimension? any reason you cant get it machined out of billet alloy or is that a cost issue?

Crasherfromwayback
7th October 2012, 16:23
hayd3n worked at the foundry down here a few years ago, he may know more details around what they can or cant do.

what are your dimension? any reason you cant get it machined out of billet alloy or is that a cost issue?

I'll track him down and PM him. Cheers for the heads up. Short story longer...it's for the SR500 I have coming (the bike in my avatar). Ain't no bits floating round for them...Kawasaki only built four of 'em. I don't want billet bits...I'm really anal about shit being correct. Especially on such bikes.

Chur.

schrodingers cat
7th October 2012, 17:23
Do you think the original was gravity sand cast or pressure die cast?
It would be quite involved to produce the pattern and get a good quality gravity casting.

Why not billet then sand or shot blast to get to appearance right?

Crasherfromwayback
7th October 2012, 17:28
Do you think the original was gravity sand cast or pressure die cast?
It would be quite involved to produce the pattern and get a good quality gravity casting.

Why not billet then sand or shot blast to get to appearance right?

Not sure which method they'd use for the originals mate.

Guess we could do that...but would've thought the finish was hard to duplicate? Also thought the cost would be worse?

Ocean1
7th October 2012, 18:36
Not sure which method they'd use for the originals mate.

Guess we could do that...but would've thought the finish was hard to duplicate? Also thought the cost would be worse?

Depends on numbers, more than a few hundred and they'd probably be die-cast, less than that may have been shell molded. Don't matter, you can't afford the first and the results of the second are indistinguishable. You just have to make a pattern out of treewood/bog. Call Borren Metal Forming in Paraparaumu, (04-298 5034), think they're still into shell molding.

Oh, and the cost is going to be bad however you do it mate, CNC milling it from a lump and blasting it doesn't require any one-off tooling. And it'd be stronger for the same weight. Which raises the question: how can you describe the original shape?

Grumph
7th October 2012, 18:56
The foundry in Nelson which does the gearbox cases for TT Industries is accustomed to working in Elektron which is what you'd use.

I understand they do a fair bit of one off work too.

neels
7th October 2012, 19:00
There is an outfit in chch that does custom casting, the old man has had them make various bits for his vintage cars, do you have originals to make moulds from?

Crasherfromwayback
7th October 2012, 19:11
Depends on numbers, more than a few hundred and they'd probably be die-cast, less than that may have been shell molded. Don't matter, you can't afford the first and the results of the second are indistinguishable. You just have to make a pattern out of treewood/bog. Call Borren Metal Forming in Paraparaumu, (04-298 5034), think they're still into shell molding.

Oh, and the cost is going to be bad however you do it mate, CNC milling it from a lump and blasting it doesn't require any one-off tooling. And it'd be stronger for the same weight. Which raises the question: how can you describe the original shape?

Dunno how many KHI would've made...doubt it was too many. Really appreciate your help and thoughts. I will more than likely be able to get the itmes I need from a geezer in Aust that has the same bike. He wants my spare SR250 engine real bad...and will swap me most of an SR500 engine. It's that engine I need the cases for.


The foundry in Nelson which does the gearbox cases for TT Industries is accustomed to working in Elektron which is what you'd use.

I understand they do a fair bit of one off work too.

Awesome. Many thanks.


There is an outfit in chch that does custom casting, the old man has had them make various bits for his vintage cars, do you have originals to make moulds from?

Really appreciate the heads up. I'll get it touch with them.

bogan
7th October 2012, 19:12
I seem to recall the auckland uni guys getting some parts done by lost foam casting. The foam gets machined to shape, the put in a sand mold, the foam fucks off as the metal goes in. With savings on magnesium compared to the CNC billet approach it might be worth looking into if you don't have an original part to pull a mold from.

Ocean1
7th October 2012, 19:17
I seem to recall the auckland uni guys getting some parts done by lost foam casting. The foam gets machined to shape, the put in a sand mold, the foam fucks off as the metal goes in. With savings on magnesium compared to the CNC billet approach it might be worth looking into if you don't have an original part to pull a mold from.

Good trick eh? An updated version of the lost wax method.

Unfortunatley not the best for thin-wall sections, no sand casting method is really.

Crasherfromwayback
7th October 2012, 19:18
I seem to recall the auckland uni guys getting some parts done by lost foam casting. The foam gets machined to shape, the put in a sand mold, the foam fucks off as the metal goes in. With savings on magnesium compared to the CNC billet approach it might be worth looking into if you don't have an original part to pull a mold from.

That's cool. I will have the original part...so maybe that'll help. I will settle with alloy too if mag is too expensive.

Crasherfromwayback
7th October 2012, 19:20
Good trick eh? An updated version of the lost wax method.

Unfortunatley not the best for thin-wall sections, no sand casting method is really.

Yeah it is! I remember doing sand casting at Naenae College in metal work class. Loved it. Didn't love getting cracked over the head with a soldering bar for talking while the teacher was though. Fucking hurt.

AllanB
7th October 2012, 19:22
I've used the Casting Shop in CHCH (Watts Rd) to make some one off custom parts for my bike from patterns I made - came out well and they were very helpful.

Crasherfromwayback
7th October 2012, 19:25
I've used the Casting Shop in CHCH (Watts Rd) to make some one off custom parts for my bike from patterns I made - came out well and they were very helpful.

Cheers for that. I'll get it touch with them. Really appreciate the help.

bogan
7th October 2012, 19:30
Good trick eh? An updated version of the lost wax method.

Unfortunatley not the best for thin-wall sections, no sand casting method is really.

I had wondered about that, it says the minimum wall thickness is 2.5mm, which would be about right for this sort of work. However I have a suspicion machining foam to 2.5mm could be tricky... and whether that 2.5mm is normally achievable or if it takes extra time/gear.

I've seen a youtube of a guy with a foam mill (5 axis iirc), pretty much the size of a small bedroom. Machined foam molds for fiberglass, LFC, whatever he could think of. Did a canoe in one piece. Not sure if he did, but would be ideal to slam a laser distance sensor on it; scan, machine, cast a part all in a day or two!

Crasherfromwayback
7th October 2012, 19:36
I've seen a youtube of a guy with a foam mill (5 axis iirc), pretty much the size of a small bedroom. Machined foam molds for fiberglass, LFC, whatever he could think of. Did a canoe in one piece. Not sure if he did, but would be ideal to slam a laser distance sensor on it; scan, machine, cast a part all in a day or two!

Stop it. You're giving me a stiffy.

bogan
7th October 2012, 19:39
Stop it. You're giving me a stiffy.

Quick, put it in the laser scanner; hell, you could even scale it up a bit before machining.

Crasherfromwayback
7th October 2012, 19:45
Quick, put it in the laser scanner; hell, you could even scale it up a bit before machining.

The laser scanner has a lens as powerful as a magnifying glass? Rach has been away for nearly 3 months...I've worn it to a stump.

TMI?:innocent:

bogan
7th October 2012, 19:48
The laser scanner has a lens as powerful as a magnifying glass? Rach has been away for nearly 3 months...I've worn it to a stump.

TMI?:innocent:

Hhmmm, maybe not then, the laser might sizzle whats left.

But lets be honest, if any of us had one, it would only be a matter of time until somebodies junk got scanned.

HenryDorsetCase
7th October 2012, 19:48
That's cool. I will have the original part...so maybe that'll help. I will settle with alloy too if mag is too expensive.

one of my mates does precision CNC machining i f you end up going down that route. They do all sorts of stuff. If you co down that road I will put you in touch. If he can't/doesnt want to, he will likely know who.

You could do a John Britten and get a pottery kiln and DIY it.

hayd3n
7th October 2012, 19:59
hayd3n worked at the foundry down here a few years ago, he may know more details around what they can or cant do.

what are your dimension? any reason you cant get it machined out of billet alloy or is that a cost issue?

thing is i had a spare that i could copy and i had them cast in green sand

Crasherfromwayback
7th October 2012, 20:08
thing is i had a spare that i could copy and i had them cast in green sand

Hey there. I not be wanting a green clutch cover...but do you know of someone that might be able to make me a nice grey coloured one?

Ocean1
7th October 2012, 20:10
I've seen a youtube of a guy with a foam mill (5 axis iirc), pretty much the size of a small bedroom. Machined foam molds for fiberglass, LFC, whatever he could think of. Did a canoe in one piece. Not sure if he did, but would be ideal to slam a laser distance sensor on it; scan, machine, cast a part all in a day or two!

There was talk 10 years ago of a 5 axis unit under construction in Ak that could handle Whitbread 60molds in one hit. I found out about that one while working up a business plan for a digitiser of similar size. Which simply demonstrated why nobody else had bothered, it'd never pay for it's floorspace let alone the capital. And yes, I'd accounted for revenue in Ctrl C and Ctrl V functions.

Laser's aren't that usefull, though, too much random data, difficult to model from.

bogan
8th October 2012, 08:06
There was talk 10 years ago of a 5 axis unit under construction in Ak that could handle Whitbread 60molds in one hit. I found out about that one while working up a business plan for a digitiser of similar size. Which simply demonstrated why nobody else had bothered, it'd never pay for it's floorspace let alone the capital. And yes, I'd accounted for revenue in Ctrl C and Ctrl V functions.

Laser's aren't that usefull, though, too much random data, difficult to model from.

That is pretty fucking massive, I'd definitely be able to use that to scan my junk :innocent:

Maybe you were using shit lasers? Had a go with a lidar unit that looked pretty cool, mind you they could have used some smoothing or whatever before displaying the results...

speights_bud
8th October 2012, 08:23
If you go down the track of Billet Machining one talk to sketchy, he loves perkies and $$ too. Don't tell him i told you, but it might be something he could be interested in. His work are specialists in Aluminum machining.

Crasherfromwayback
8th October 2012, 08:25
If you go down the track of Billet Machining one talk to sketchy, he loves perkies and $$ too. Don't tell him i told you, but it might be something he could be interested in. His work are specialists in Aluminum machining.

Cheers for the heads up. I've seen some of his great work too. Didn't click!

jellywrestler
8th October 2012, 08:32
hey pete, what's wrong with the old ones and what's your budget?

HenryDorsetCase
8th October 2012, 08:55
Hey there. I not be wanting a green clutch cover...but do you know of someone that might be able to make me a nice grey coloured one?

green sand is the name of the process (in case you arent taking the piss)

http://en.wikipedia.org/wiki/Sand_casting#Green_sand

Crasherfromwayback
8th October 2012, 09:32
hey pete, what's wrong with the old ones and what's your budget?

I don't have them Spyda. My SR has a 250 SR engine in it, and I have a spare SR250 engine with it too. I'm swapping one of the 250 engines with an SR500 engine from a geezer in Aust, but his spare SR500 engine is missing the clutch cover and water pimp cover. There was only ever 4 83 SR500's built...so parts are rarer than rocking horse shit. I'm hoping he'll be good enough to let me use his covers off the complete SR500 he has to get 'em made. He seems pretty keen to get his hands on one of my SR250 engines...so I don't see it as a problem. The budget? Well...guess I'll have to pay whatever it costs...provided that ain't REAL silly money. The bike is no good without them, as they're totally different to the productionitems.


green sand is the name of the process (in case you arent taking the piss)

http://en.wikipedia.org/wiki/Sand_casting#Green_sand

Learn something every day!:innocent:

jellywrestler
8th October 2012, 09:37
I don't have them Spyda. AHHH welcome to the world of rarity, I'm looking for some handlebars for my 1924 ACE and a number plate for my 1913 King Dick. that also takes a spare tube and a drive belt, the difference is they weren't as complex as the modern stuff and can be knocked up with a bit of talent and a few night schools...
Good luck, it's 100 times easier doing that shit than ten year ago.

HenryDorsetCase
8th October 2012, 09:50
I don't have them Spyda. My SR has a 250 SR engine in it, and I have a spare SR250 engine with it too. I'm swapping one of the 250 engines with an SR500 engine from a geezer in Aust, but his spare SR500 engine is missing the clutch cover and water pimp cover. There was only ever 4 83 SR500's built...so parts are rarer than rocking horse shit. I'm hoping he'll be good enough to let me use his covers off the complete SR500 he has to get 'em made. He seems pretty keen to get his hands on one of my SR250 engines...so I don't see it as a problem. The budget? Well...guess I'll have to pay whatever it costs...provided that ain't REAL silly money. The bike is no good without them, as they're totally different to the productionitems.





My (sort of) brother in law is a hot rod guy and had some parts cast for one of his cars. I will find out who did it. They were door sill plates for a Model A ford: so quite thin with a logo cast into them. He had one and needed some others. Ive asked him who he used because it sounds very similar size and thickness wise to what you need.

Crasherfromwayback
8th October 2012, 09:54
AHHH welcome to the world of rarity, I'm looking for some handlebars for my 1924 ACE and a number plate for my 1913 King Dick. that also takes a spare tube and a drive belt, the difference is they weren't as complex as the modern stuff and can be knocked up with a bit of talent and a few night schools...
Good luck, it's 100 times easier doing that shit than ten year ago.

Hahahaha..yeah cheers! It's funny...I got hold of a guy that has a vintage works bike site, and asked him who I could talk 'bout these things. He wouldn't give me any email addys without first seeing pics of the SR. I guess they're making sure you really own one, and not just showing them pics of someone elses. Once shown the pics...that door opens. You email the contacts...same thing. Pics are swapped...that door opens! Like a Free Masons secret handshake or something! But a funny wee club. They're all really helpful guys once you get introduced to them!

And you're 100% correct. Ten years ago I'd be fucked. Now...only slightly!

Crasherfromwayback
8th October 2012, 09:56
My (sort of) brother in law is a hot rod guy and had some parts cast for one of his cars. I will find out who did it. They were door sill plates for a Model A ford: so quite thin with a logo cast into them. He had one and needed some others. Ive asked him who he used because it sounds very similar size and thickness wise to what you need.

Cheers. Really appreciate that.

schrodingers cat
8th October 2012, 12:22
It may seem an extravagance but don't discount Rapid Prototyping Tools (Scanners and 3d printing) as a way of generating a CNC program or to produce an accurate pattern.
If getting it CNC's bear in mind that it would cost too much more to get two done at the same time

Crasherfromwayback
8th October 2012, 12:32
It may seem an extravagance but don't discount Rapid Prototyping Tools (Scanners and 3d printing) as a way of generating a CNC program or to produce an accurate pattern.
If getting it CNC's bear in mind that it would cost too much more to get two done at the same time

Yeah I'll look at anything I can mate! Do you mean not cost too much more to do two?

schrodingers cat
8th October 2012, 12:39
Yeah I'll look at anything I can mate! Do you mean not cost too much more to do two?

Yes. The material cost will be the least of the job.
The cost of programming time and machine time will determine the price.
If the cover is 3D scanned it will make producing the program easier.
Since it isn't a large item getting two covers machined at the same time won't cost twice as much. (Due to half as much set up and tooling change time as getting one made and then another)

Ocean1
8th October 2012, 12:44
Maybe you were using shit lasers? Had a go with a lidar unit that looked pretty cool, mind you they could have used some smoothing or whatever before displaying the results...

Seen the one Weltech have? Most are like that, most usefull in a sort of painbrush mode, you just sweep the head over the surface and it'll scan the surface to whatever density you specify. Problem is the point cloud isn't rational wrt any model you might want to use. What you usually want is to set up the laser (or digitiser) to ping the surface at, say 10mm horozontal incriments. That way you only get the data you want to build workable surfaces / solids from.

Gremlin
8th October 2012, 12:49
Don't forget we'll need pictures of the shiny finished product. Hell, I got excited by machined up cylinders that were to act as spacers...

Guys are simple folk :yes:

Brian d marge
8th October 2012, 13:00
3d scan it , and rapid prototype it in aluminium. thats the route I would take

While I havent the reverse engineering software , it isnt that expensive so I assume someone will be using it then print it in aluminium and then make it look like Magn.

Stephen

Steve bagshaw , for the scanning in NZ ( I know he just got some quotes)

http://www.finelineprototyping.com/ for the printing in Al

http://www.nextengine.com/ not the scanner but the software to clean up the scans

Crasherfromwayback
8th October 2012, 14:19
3d scan it , and rapid prototype it in aluminium. thats the route I would take

While I havent the reverse engineering software , it isnt that expensive so I assume someone will be using it then print it in aluminium and then make it look like Magn.

Stephen

Steve bagshaw , for the scanning in NZ ( I know he just got some quotes)

http://www.finelineprototyping.com/ for the printing in Al

http://www.nextengine.com/ not the scanner but the software to clean up the scans

Awesome...cheers! Here's a pic of the beast...just collected it. Magnesium everywhere. Mmmmm.271279271280271281

Brian d marge
8th October 2012, 14:27
got lucky there , I found a download rapidform, which will give you a parametric drawing of a scanned image , its just completed downloading so Ill have a look

this was going to be my retirement job , reverse engineering unobtainium

I would be interested in your experience of the whole thing

Stephen

Grumph
8th October 2012, 14:57
What makes you think the clutch cover and waterpump are magnesium ?

The rear hub and brakeplate, yes, chromate plus probably paint visible...but the covers, no chromate coating visible which makes me think they're sandcast alloy. I've never heard of or seen a clear chromate...and dirt bikes in particular need corrosion protection.

Crasherfromwayback
8th October 2012, 15:04
What makes you think the clutch cover and waterpump are magnesium ?

The rear hub and brakeplate, yes, chromate plus probably paint visible...but the covers, no chromate coating visible which makes me think they're sandcast alloy. I've never heard of or seen a clear chromate...and dirt bikes in particular need corrosion protection.

Yeah I think the 250's are alloy...but the 5 hundy definately uses Magnesium.

Grumph
8th October 2012, 15:09
Yeah I think the 250's are alloy...but the 5 hundy definately uses Magnesium.

Well sandcast them in alloy and paint them chromate crappy brown....

Crasherfromwayback
8th October 2012, 15:10
Well sandcast them in alloy and paint them chromate crappy brown....

Yeah I'd be happy with that!

HenryDorsetCase
8th October 2012, 16:06
Email from brother in law:


Why I was asking is If you cast off the originals they end up shrinking by around 2-3%. So you need to build them up by the same approx amount. If you cast of recasts they get progressively smaller.

The one I used then is gone, but I have had a heap of stuff done at the guy in Wickham St Bromley, just down from Dyers Rd.


the guy he is talking about is this guy:

11 Wickham Street Bromley 8062‎
03-384 2584
Die Casters

There you go, FWIW.

Crasherfromwayback
8th October 2012, 16:11
Email from brother in law:




the guy he is talking about is this guy:

11 Wickham Street Bromley 8062‎
03-384 2584
Die Casters

There you go, FWIW.

Aweome. Many thanks!

husaberg
7th March 2013, 22:37
Cheers for that. I'll get it touch with them. Really appreciate the help.

What did you end up doing Pete?

Crasherfromwayback
8th March 2013, 07:33
What did you end up doing Pete?

Emailed an shitload of places with sad replies. Nione of the ones I contacted seem to want to know about it.

Ocean1
8th March 2013, 09:10
Emailed an shitload of places with sad replies. Nione of the ones I contacted seem to want to know about it.

Yeah. People have become so used to prices driven by mass production and cheap labour that anyone asked to produce a one-off really struggles to convince their clients they can't do it for even ten times that price.

Did you get your hands on an original Pete?

Crasherfromwayback
8th March 2013, 09:24
Yeah. People have become so used to prices driven by mass production and cheap labour that anyone asked to produce a one-off really struggles to convince their clients they can't do it for even ten times that price.

Did you get your hands on an original Pete?

I've put it back on the geezer that has the bits I want, as he's desperate to get his hands on my spare SR250 works engine. Seems it's even more rare than the SR500's. Being in Australia, I'm hoping he'll have a better chance of finding someone that'll make them from his originals.

Ocean1
8th March 2013, 13:48
I've put it back on the geezer that has the bits I want, as he's desperate to get his hands on my spare SR250 works engine. Seems it's even more rare than the SR500's. Being in Australia, I'm hoping he'll have a better chance of finding someone that'll make them from his originals.

OK. If you get stuck let me know, eh?

Crasherfromwayback
8th March 2013, 13:57
OK. If you get stuck let me know, eh?

Yeah will do cheers!

husaberg
8th March 2013, 15:56
Yeah will do cheers!

Talk to fletner (Neil Hintz)

He will sort you out.Shame you don't have a pattern it should be a simple matter to copy cast it.
Neal has made Kawa big horn heads with this method.
I personally would make it thicker and mill off the the excess.

Crasherfromwayback
8th March 2013, 16:22
Talk to fletner (Neil Hintz)

He will sort you out.Shame you don't have a pattern it should be a simple matter to copy cast it.
Neal has made Kawa big horn heads with this method.
I personally would make it thicker and mill off the the excess.

Yeah getting the geezer to trust me with his SR500 covers is proving difficult...which is a bastard, as it's the only thing stopping me from making mine complete. I can then use my 250 engine to make an SR250 replica as well.