A question for the Engineers on the site

**bogan** · 7th October 2012, 19:30

Originally Posted by Ocean1

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

Originally Posted by bogan

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

Originally Posted by Crasherfromwayback

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

Originally Posted by bogan

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?

**bogan** · 7th October 2012, 19:48

Originally Posted by Crasherfromwayback

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?

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

Originally Posted by Crasherfromwayback

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

Originally Posted by tigertim20

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

Originally Posted by hayd3n

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

Originally Posted by bogan

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

Originally Posted by Ocean1

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

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

Originally Posted by speights_bud

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

Originally Posted by Crasherfromwayback

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

Originally Posted by jellywrestler

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.

Originally Posted by HenryDorsetCase

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!