Watcon pitch gauge gives surprising results

[Ultra/RXP]

The following are the measurements of my untouched Solas 14/19R. Leading edge pitch: 12,12,12,12. Trailing edge: 19,17,18,15. These readings were taken using the Waton instuctions "find the line on the gauge that aligns with the center (of the thickness) of the impeller blade at the very end. In all fairness, for the leading edge, if you measure the thrust side of the blade the numbers would be 13,13,13,13. But at least these were consistant. Maybe there are variations between gauges. The trailing edge numbers are really concerning. The corresponding measurements from a flat surface to 1" from the trailing edge were: 13 mm,12 mm, 13 mm, 11 mm. They say small changes to the impeller can make big changes in performance.

A couple of years ago, I had my stock impeller repitched by one of the big impeller shops. This was to be used with a Riva Stage 1 setup. I was never able to turn that prop at proper RPM. The shop offered to redo it but at the time I bought a 14/19 instead. I now know why I couldn't turn it. Trailing edge:20,21,21,20. Leading edge:12,11,11,11.

My point is, you guys trying to get every .1 MPH or wonder why some boats are faster than others with the same setup, this could be one of the areas to look at.

I think the $100 for the gauge is well worth it, especially if a group of you guys could share one. And no I have no affiliation with Watcon, I didn't know they existed until two weeks ago.

[jetskibill9999]

The following are the measurements of my untouched Solas 14/19R. Leading edge pitch: 12,12,12,12. Trailing edge: 19,17,18,15. These readings were taken using the Waton instuctions "find the line on the gauge that aligns with the center (of the thickness) of the impeller blade at the very end. In all fairness, for the leading edge, if you measure the thrust side of the blade the numbers would be 13,13,13,13. But at least these were consistant. Maybe there are variations between gauges. The trailing edge numbers are really concerning. The corresponding measurements from a flat surface to 1" from the trailing edge were: 13 mm,12 mm, 13 mm, 11 mm. They say small changes to the impeller can make big changes in performance.

A couple of years ago, I had my stock impeller repitched by one of the big impeller shops. This was to be used with a Riva Stage 1 setup. I was never able to turn that prop at proper RPM. The shop offered to redo it but at the time I bought a 14/19 instead. I now know why I couldn't turn it. Trailing edge:20,21,21,20. Leading edge:12,11,11,11.

My point is, you guys trying to get every .1 MPH or wonder why some boats are faster than others with the same setup, this could be one of the areas to look at.

I think the $100 for the gauge is well worth it, especially if a group of you guys could share one. And no I have no affiliation with Watcon, I didn't know they existed until two weeks ago.

fair play to you, i'll have to get one cos i'm still measuring my trailin edge on a flat suface, i must say though when my retrimmed prop goes back in, with a new wear ring its all new again, my 05 has eaten 7 wear rings already

[cyoungesq]

I was checking these out but not sure which size diameter to get . . . which one is needed for our impellers?

[Hydrotoys]

A bunch of folks have mentioned that the blades being pitched off a little is not an accident.

Make it perfect, and you may/may not make it better.

[Ultra/RXP]

A bunch of folks have mentioned that the blades being pitched off a little is not an accident.

Make it perfect, and you may/may not make it better.

I can't say you're not right, but I would be really, really, really, amased.

[jawz]

I can't say you're not right, but I would be really, really, really, amased.

I HAD a really good impeller and cleaned it up... it was never the same.

[Ultra/RXP]

The Solas 14/19 I descibed did perform better after I cleaned it up. If there is a benefit for an impeller to be "off a bit", it would not be in some random way. You know there actually is science and physics behind the design of an impeller. If you told me every other blade should be 1 degree different and why, that would be a different discussion.

[dan725]

The following are the measurements of my untouched Solas 14/19R. Leading edge pitch: 12,12,12,12. Trailing edge: 19,17,18,15. These readings were taken using the Waton instuctions "find the line on the gauge that aligns with the center (of the thickness) of the impeller blade at the very end. In all fairness, for the leading edge, if you measure the thrust side of the blade the numbers would be 13,13,13,13. But at least these were consistant. Maybe there are variations between gauges. The trailing edge numbers are really concerning. The corresponding measurements from a flat surface to 1" from the trailing edge were: 13 mm,12 mm, 13 mm, 11 mm. They say small changes to the impeller can make big changes in performance.

A couple of years ago, I had my stock impeller repitched by one of the big impeller shops. This was to be used with a Riva Stage 1 setup. I was never able to turn that prop at proper RPM. The shop offered to redo it but at the time I bought a 14/19 instead. I now know why I couldn't turn it. Trailing edge:20,21,21,20. Leading edge:12,11,11,11.

My point is, you guys trying to get every .1 MPH or wonder why some boats are faster than others with the same setup, this could be one of the areas to look at.

I think the $100 for the gauge is well worth it, especially if a group of you guys could share one. And no I have no affiliation with Watcon, I didn't know they existed until two weeks ago.

I know this is an old thread, but I have to say that Every prop I've sent to have repitched came back scrap.

[SeaGoat]

If you're going to mod your ski a little here and a little there then the watcon is a must buy. My oem prop was different on all 4 blades and after matching them up and making them the pitch they were supposed to be, my ski picked up 1.5 mph.

[skoepp]

The following are the measurements of my untouched Solas 14/19R. Leading edge pitch: 12,12,12,12. Trailing edge: 19,17,18,15. These readings were taken using the Waton instuctions "find the line on the gauge that aligns with the center (of the thickness) of the impeller blade at the very end. In all fairness, for the leading edge, if you measure the thrust side of the blade the numbers would be 13,13,13,13. But at least these were consistant. Maybe there are variations between gauges. The trailing edge numbers are really concerning. The corresponding measurements from a flat surface to 1" from the trailing edge were: 13 mm,12 mm, 13 mm, 11 mm. They say small changes to the impeller can make big changes in performance.

A couple of years ago, I had my stock impeller repitched by one of the big impeller shops. This was to be used with a Riva Stage 1 setup. I was never able to turn that prop at proper RPM. The shop offered to redo it but at the time I bought a 14/19 instead. I now know why I couldn't turn it. Trailing edge:20,21,21,20. Leading edge:12,11,11,11.

My point is, you guys trying to get every .1 MPH or wonder why some boats are faster than others with the same setup, this could be one of the areas to look at.

I think the $100 for the gauge is well worth it, especially if a group of you guys could share one. And no I have no affiliation with Watcon, I didn't know they existed until two weeks ago.

I check all my props and others on Watcon. Findings are always very imformative.
I suggest once you have checked your props and tested them, take that data and let a pro repitch it for you.
It is the cheapest mod you can do once you start modding.