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Would like to build my own trigger wheel using some water cutting shop. Anyone know where to find such a shop ?

I've used http://www.emachineshop.com/
these are pricey buy they would build anything you ask for.

i did it with local laser cutters (1000km away from moskau) for somewhat 5£

bjorkmanders wrote:Would like to build my own trigger wheel using some water cutting shop. Anyone know where to find such a shop ?

Would have been nice with such a shop nearby

russian wrote:I've used http://www.emachineshop.com/
these are pricey buy they would build anything you ask for.

Thanks, will look them up

yeah! I was lucky! but I did extensive search before I found them. They do not look like a customer-oriented business (although they had a web-site, it hadn't changed since its launch in 2007), but they really are, and they keep their prices low. I bet, if I ordered it here in Moskau, that would be at least $70…
Sometimes it seems it's cheaper to get a metal lathe)

Well heres my first drawing, does it work ? Or should i redraw something ? Is 36 teeth a good count or should I change it ? Will of course remove one teeth ....

1. I find it way easier to have all those mounting holes drilled at the same time with the main job. + the missing tooth. believe me, you don't want to use a disc grinder to do that - it's much easier to do it in the drawing.
2. people say the teeth size should somehow relate to your VR sensor design (haven't checked though) - perhaps, it would be more practical to stick to some proven pair of disc(tooth) size/sensor model?
3. probably it would be nice to take all measures to retain balance (at least my crank pulley has some balancing weights on it) - so why not drill a hole opposite the missing tooth?
4. not sure what are the requirements of the workshop that would do the job. my laser guys wanted autodesk 2010 file format or something like that... not a raster image anyway

I helped some one here with a design. We used draftsight to predict the centroid. We then cut holes until the centroid was centered on the shaft.

I seem to recall e-machine shop allow uploading of a DWG or DXS. So I think you can make it and mounting holes in DXS or DWG land then simply import the file into e-machine ship.

I generally find local shops are much lower cost than e-machine shop. I generally find e-machine shop is good for fast quotes, which can allow for fast and accurate upstream quotes. AKA fast turn around for an upstream customer, but probably not the cheapest option.

puff wrote:1. I find it way easier to have all those mounting holes drilled at the same time with the main job. + the missing tooth. believe me, you don't want to use a disc grinder to do that - it's much easier to do it in the drawing.
2. people say the teeth size should somehow relate to your VR sensor design (haven't checked though) - perhaps, it would be more practical to stick to some proven pair of disc(tooth) size/sensor model?
3. probably it would be nice to take all measures to retain balance (at least my crank pulley has some balancing weights on it) - so why not drill a hole opposite the missing tooth?
4. not sure what are the requirements of the workshop that would do the job. my laser guys wanted autodesk 2010 file format or something like that... not a raster image anyway

1. Yep it was only for showing the teethshape
2. Is it the same with hall sensor ?
3. Good idea
4. Yep dwg should work ...

kb1gtt wrote:I helped some one here with a design. We used draftsight to predict the centroid. We then cut holes until the centroid was centered on the shaft.

I seem to recall e-machine shop allow uploading of a DWG or DXS. So I think you can make it and mounting holes in DXS or DWG land then simply import the file into e-machine ship.

I generally find local shops are much lower cost than e-machine shop. I generally find e-machine shop is good for fast quotes, which can allow for fast and accurate upstream quotes. AKA fast turn around for an upstream customer, but probably not the cheapest option.

Could be that I have found a cheaper shop then the e-machine shop

Here's rev2 of my tooth wheel. What do you think ?

What is the current cost estimate on fabricating this?

On the one hand that's probably not rocket science, on the other hand do we know how much metal has to be removed in the tooth for the VR to do the magic?

I guess my question is anything more OEMinsh could be custom-fit to simplify the project in this aspect?

For some math that might be handy for predicting LxWxH of the teeth, see this post http://rusefi.com/forum/viewtopic.php?f=4&t=258&start=144 it notes a reference that helps describe how those parameters effect the final signal.

russian wrote:What is the current cost estimate on fabricating this?

On the one hand that's probably not rocket science, on the other hand do we know how much metal has to be removed in the tooth for the VR to do the magic?

I guess my question is anything more OEMinsh could be custom-fit to simplify the project in this aspect?

I will look it up this week ...

When creating the trigger wheel I follow the specs for this hall-sensor http://www.diyautotune.com/catalog/hall-effect-crankshaft-position-sensor-p-479.html since it worked so well for mee in the past

If the price goes to high, I will look at some oem solution Although it will take me more time in the shop fit it in the engine

kb1gtt wrote:For some math that might be handy for predicting LxWxH of the teeth, see this post http://rusefi.com/forum/viewtopic.php?f=4&t=258&start=144 it notes a reference that helps describe how those parameters effect the final signal.

Great reading !