What's This?!?!

[AndyBrown]

Added another prop today. The 4569/3 Dia.=45mm Pitch=69mm T.E. is at 3.4"

So now we have three props, 5082, 4773 and 4569, both left and right. I'll do a 2 blade version of these soon.

Brad, The first 21 rigger prop will be a 4576. Progression will be about 25% to keep it user friendly for a wide

range of riggers. I will do more versions so there will be something for every set of conditions.

Thanks to everyone who has ordered the new props.

More to come!

 

[AndyBrown]

The newest props, 4569 L&R and 4773 L&R will be on sale for $30 until midnight Wed. Mar.19.

You may also preorder any of the three new props in the two blade version.

We want to give many of you a chance to try out these new props.

Good boating,

Andy

 

[Marty Davis]

I had a chance to look at these props this past weekend at the Brandon Race. I doubt that ANY of you have had a prop that is as sharp as it comes right from Andy. I couldn't believe how sharp it is.

Should be interesting to see how it runs and holds up.

Might even be a good prop for my 20 hydro?

Marty Davis

 

[Akiuk]

7075 AL ALY can be machined at or above 2000 SFM, 41XX Alloy steels ( annealed) 300-600 SFM, 41XX Alloy (pre-hard) 200-400 SFM,

17-4PH ( annealed) 90-300 SFM( 17-4 is tough on tools). Caveat: machining conditions will affect #s and every body has their own opinion.

I will agree with others here ; Alloy steels will move during heat treat, some geometries move alot !!! and built up machinig stress effects this also.

17-4 is pretty stable compared to most thru hardened Alloy steels during heat treat.

Two things are for sure, switching from AL ALY, cycle times will grow "alot" per part and tool wear will go up, especially the small dia. cutters needed for the small fillets and 3D work .

Depending upon the tolerence you need to hold, you may have to rough the part to within .010-.020 of finish size, heat treat, and finish machine.

If no heat treating is envolved and tolerence is +/- .010 , let her eat.......

 

[Ray Sametz]

Andy, Got props today, WOW, let you know how it runs on Sport 40. Weather is starting to cooperate. B) B) B) B)

 

[AndyBrown]

7075 AL ALY can be machined at or above 2000 SFM, 41XX Alloy steels ( annealed) 300-600 SFM, 41XX Alloy (pre-hard) 200-400 SFM, 17-4PH ( annealed) 90-300 SFM( 17-4 is tough on tools). Caveat: machining conditions will affect #s and every body has their own opinion.

I will agree with others here ; Alloy steels will move during heat treat, some geometries move alot !!! and built up machinig stress effects this also.

17-4 is pretty stable compared to most thru hardened Alloy steels during heat treat.

Two things are for sure, switching from AL ALY, cycle times will grow "alot" per part and tool wear will go up, especially the small dia. cutters needed for the small fillets and 3D work .

Depending upon the tolerence you need to hold, you may have to rough the part to within .010-.020 of finish size, heat treat, and finish machine.

If no heat treating is envolved and tolerence is +/- .010 , let her eat.......

Today I machined a 4773 out of some 41XX prehard to 42 RC. It worked out better than I expected. Very thin and very sharp. Very accurate. It came off the machine balanced! However I've got to get the cylce time down before anyone will want to pay for one.

 

[Akiuk]

7075 AL ALY can be machined at or above 2000 SFM, 41XX Alloy steels ( annealed) 300-600 SFM, 41XX Alloy (pre-hard) 200-400 SFM, 17-4PH ( annealed) 90-300 SFM( 17-4 is tough on tools). Caveat: machining conditions will affect #s and every body has their own opinion.

I will agree with others here ; Alloy steels will move during heat treat, some geometries move alot !!! and built up machinig stress effects this also.

17-4 is pretty stable compared to most thru hardened Alloy steels during heat treat.

Two things are for sure, switching from AL ALY, cycle times will grow "alot" per part and tool wear will go up, especially the small dia. cutters needed for the small fillets and 3D work .

Depending upon the tolerence you need to hold, you may have to rough the part to within .010-.020 of finish size, heat treat, and finish machine.

If no heat treating is envolved and tolerence is +/- .010 , let her eat.......

Today I machined a 4773 out of some 41XX prehard to 42 RC. It worked out better than I expected. Very thin and very sharp. Very accurate. It came off the machine balanced! However I've got to get the cylce time down before anyone will want to pay for one.

That will be a hell of a strong prop, using 41XX series prehard material!!!!!!

I have been out of boats for a long time, but back then as now, it apears, you guys do the cutting edge stuff. No pun intended with "cutting edge"

best wishes to CMDI !

 

[Joe_Knesek]

I received my prop yesterday & can't believe how nice it is. Now I need Andy to figure out how to keep our pond from freezing so I can actually run it.

 

[moparbarn]

I received my prop yesterday & can't believe how nice it is. Now I need Andy to figure out how to keep our pond from freezing so I can actually run it.

go BURN UP the water with that new prop. should be boiling by the first tank :lol: :lol: !

 

[bzubee]

Got mine yesterday looks very nice I took it to work for Show & Tell

 

[tnrcboatracer]

Got mine today, too. SWEET! I can hardly wait to try it out on my SP40.

 

[AndyBrown]

Hard steel on left.

4569 in 7075-T6 on right.

 

[Andy Greene]

Hard steel on left.
4569 in 7075-T6 on right.

SWEEEET - Let me wipe the drool off now

 

[moparbarn]

what drew said !

 

[TomMoorehouse]

Andy you have a good .21 hydro prop ready? You know what engine I have!

 

[LarryConrad]

It's the first day of spring! and I received my props today!...and three inches of fresh snow. No open water yet.

Larry

 

[bsmtboy2]

My props came today,all i can say is WOW the craftsmanship shows on the these props!!! Keep up the good work Andy. If the weather holds out i will give some feedback by Sunday nite.

 

[AndyBrown]

Andy you have a good .21 hydro prop ready? You know what engine I have!

What prop do you normally run Tom?

 

[TomMoorehouse]

Andy you have a good .21 hydro prop ready? You know what engine I have!

What prop do you normally run Tom?

the 1445 from you.... but cant make 70 with it.

did you get my pm??

 

[AndyBrown]

Andy you have a good .21 hydro prop ready? You know what engine I have!

What prop do you normally run Tom?

the 1445 from you.... but cant make 70 with it.

did you get my pm??

I don't have that type of prop yet Tom. How much nitro?