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View Full Version : Fab Help Needed - mill/cnc/laser


Beater
12-22-2009, 08:19 PM
ok - so I have this nifty idea to put carbs from a ducati on my cafe bike.. I need to have a intakes fabbed up, and I don't think I can do it by hand.

The new carbs are off-center by about 3-4mm, and a little larger on the spigot, but very close. I am thinking that new aluminum or ss manifolds could be made, with a step over to fix the offset and the intake sizing. I am not worried about the venturi effect, as this isn't a race motor anyway.

I will be in the shop ALL day tomorrow, either fabbing, beating metal or "partaking of the season", so hit me up on my cell or stop by... I'll have the stove on..

I don't do cad, or I'd post something up.


johnny - 303 nine o six, 8693

TIMZTOY
12-22-2009, 10:16 PM
i do some cad, but my fabricator with the 4 axis cnc is in missouri. so i dont have a local connection.. i need one if someone knows anyone..

rover67
12-22-2009, 11:28 PM
I could cad something for you that could be used to program a 4 or 5 axis mill, but I don't know anybody that might be able to mill it for free. I am sure a few of the shops I work with would be willing to do it for some kinda price though. If somebody knew somebody with a 3 axis cnc it could still be done, but you'd be limited to how complex you could make it since you'd probably have to flip it on the mill.

You sure you don't want to tig something up out of some nice stainless? What do these look like they need to be? Are they really really short?

You might want to look at sand casting something? That might be a fun project and you could probably do it all in your shop.. I've always wanted to cast a manifold.

Red_Chili
12-23-2009, 11:37 AM
I just knew you would kiss those tiny CV carbs good-bye...
Use a pair of pumpers, baby. Watch the front wheel get light.

nakman
12-23-2009, 12:08 PM
How hot would they get? Over 350F?

rover67
12-23-2009, 12:12 PM
How hot would they get? Over 350F?

My vote is do what you are thinking but use the part as a mold for the casting... :D

nakman
12-23-2009, 12:16 PM
I agree, do a sand casting! yeah I can help with the master pattern.. ;)

But I find it funny how people's paradigms are- some immediately assume machined or welded metal is the only way to go. And of course I see the world in all plastics..

rover67
12-23-2009, 01:27 PM
Hey I had an open mind!!

I think it'd be a sweet project, something nak could showcase perhaps.

Beater
12-23-2009, 05:54 PM
They are rubber now, but mate directly to the head, intake side of course. I am open to ideas. I am almost certainly going with individual carbs now, or I can re-rack a set of pumpers. I found 32mm pumpers, but I have 32 non-pumps now. Would like to get a few more cfm with the shorter pipes.

The problem would be rigidity, as the would need to isolate vibration some. I could use sleeves, but I don't have much room.

Oh, and bill, accelerator pump carbs are like unobtainium on a budget.

TIMZTOY
12-23-2009, 10:08 PM
i do some cad, but my fabricator with the 4 axis cnc is in missouri. so i dont have a local connection.. i need one if someone knows anyone..

sorry water jet is what im needing.. if anyone knows.. sorry for jacking..

rover67
12-23-2009, 10:59 PM
do stainless flanges with lips welded on for a short peice of rubber hose maybe?

Beater
12-24-2009, 08:28 AM
do stainless flanges with lips welded on for a short peice of rubber hose maybe?

Yeah - The problem is the warpage from heat. I would like to avoid it if I could. I am waiting on what the final carb solution is, then I think we should all have several beers next to the woodstove while we put the plan in motion.

j

Beater
12-24-2009, 09:59 AM
well - no need to fab. I found after about 6 hours of research, someone had already done this on a kz440, the twin to my bike, but in cruiser-ish form. Mikuni makes a 60 on center spigot, that I can just widen the bolt center dimensions on when I move to vm34 carbs.

For now, I will just swap out my old keihin cv's for newer mikunis with better circuitry and keep my eye out for some vm's when they come open or some tm33's with a pump.