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General control line discussion => Open Forum => Topic started by: Luis Strufaldi on November 17, 2014, 08:00:25 AM

Title: PA51 Spinner
Post by: Luis Strufaldi on November 17, 2014, 08:00:25 AM
Hello Everyone

I recently acquired a PA51 and I wanted to try to get some of those carbon fiber spinners at Hobbyking.

Can anyone tell me, from the top of their heads, what diameter prop nut adapter I should get for the PA?

Thanks!

Luis S
Title: Re: PA51 Spinner
Post by: Paul Taylor on November 17, 2014, 08:40:23 AM
What is the link to the spinner?


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Title: Re: PA51 Spinner
Post by: Luis Strufaldi on November 17, 2014, 09:11:55 AM
http://www.hobbyking.com/hobbyking/store/__10185__Carbon_Fiber_prop_Spinner_51mm_2in_diameter.html
Title: Re: PA51 Spinner
Post by: Steve Thomas on November 17, 2014, 01:41:41 PM
While we're at it, any suggestions on the best way to make the prop blade cutouts in these? I'm thinking maybe a Dremel with cutoff wheel, but am open to ideas.

Steve
Title: Re: PA51 Spinner
Post by: Randy Cuberly on November 17, 2014, 05:39:19 PM
I'm not sure exactly what you're asking for but the PA51 as all of the PA's has a 5/16 (.312) diameter shaft!

Randy Cuberly
Title: Re: PA51 Spinner
Post by: Paul Taylor on November 17, 2014, 06:01:29 PM
Thanks Luis!😉
Title: Re: PA51 Spinner
Post by: Alan Buck on November 17, 2014, 07:33:38 PM
the pa40 u/l has 1/4'' shaft not 5/16''
Title: Re: PA51 Spinner
Post by: Steve Helmick on November 17, 2014, 08:00:24 PM
the pa40 u/l has 1/4'' shaft not 5/16''

Well...it is a .51, so it's a 5/16-24. The PA .40UL has a 1/4-28 thread, and is the only PA that does, other than the Aero Tiger .36, which is only sort of a PA. I haven't looked at the Hobby King link yet, but for me, there always seems to be some machining/adapting required. Probably bring it on myself?  H^^ Steve 
Title: Re: PA51 Spinner
Post by: Luis Strufaldi on November 18, 2014, 04:28:36 AM
Almost all the prop nuts Hoobyking have are metric ones (M3, M4, M5...)

http://www.hobbyking.com/hobbyking/store/RC_PRODUCT_SEARCH.asp?strSearch=brass+nut+for+spinner

I have found the following site showing how inch threads relate to metric threads (this is frustraiting!!!! HB~> HB~> HB~> HB~>)

http://m3service.com/metricinch-comparisons/

So, basically, I'd need an M8x1.0 nut, right? Or am I the nut?? n~ n~
Title: Re: PA51 Spinner
Post by: Randy Cuberly on November 18, 2014, 09:41:20 AM
Almost all the prop nuts Hoobyking have are metric ones (M3, M4, M5...)

http://www.hobbyking.com/hobbyking/store/RC_PRODUCT_SEARCH.asp?strSearch=brass+nut+for+spinner

I have found the following site showing how inch threads relate to metric threads (this is frustraiting!!!! HB~> HB~> HB~> HB~>)

http://m3service.com/metricinch-comparisons/

So, basically, I'd need an M8x1.0 nut, right? Or am I the nut?? n~ n~

No and M8X1.0 is an equivalent size and strength but the thread is slightly different in pitch a dn root diameter, and will not fit on a 5/16-24 UNF thread!

Randy Cuberly
PS:  the original PA 40 (large case) also had a 5/16-24 shaft.  I have two each of all the PA engines except for the 40 UL.
Title: Re: PA51 Spinner
Post by: Brett Buck on November 18, 2014, 09:53:39 AM
So, basically, I'd need an M8x1.0 nut, right? Or am I the nut?? n~ n~

  I don't think that will work. I also don't understand why they would have metric, almost all engines, even those from metric countries, have UNF threads. And UNEF glow plugs.

     Brett
Title: Re: PA51 Spinner
Post by: Steve Helmick on November 18, 2014, 11:44:05 AM
I'd suggest a close inspection of Dave Brown and Tru-Turn spinner accessories on the Tower Hobbies site. They will not have a metric thread for the coaxial mounting screw, but it's a start. On second thought, you might check the Hobby People site for Magnum spinner accessories...they may very well have metric threads for the mounting screw. Maxx Products is another place to look for metric adapters. The url's for these sites are as close as your Model Aviation magazine...or Google...but if you need help, I probably can dig out the links.  y1 Steve

 
Title: Re: PA51 Spinner
Post by: Steve Thomas on November 18, 2014, 01:53:52 PM
Luis, they sell a couple of different types of carbon spinner. If you get this one:  http://www.hobbyking.com/hobbyking/store/__25680__2_Inch_Carbon_Fiber_Spinner.html
the cone is held on with a couple of screws and you won't need an adapter.

Steve
Title: Re: PA51 Spinner
Post by: Chris Wilson on November 19, 2014, 12:35:47 AM
While we're at it, any suggestions on the best way to make the prop blade cutouts in these? I'm thinking maybe a Dremel with cutoff wheel, but am open to ideas.

Steve
Hi Steve,
           a Dremel cut off wheel is a thin high speed disk only suitable for cutting straight lines slowly. There would be no way I would use one to arc out a spinner cone as it could shatter and become dangerous. (And yes I have used a Dremel quite extensively.)

Quote from the Dremel web site -
"User Tips
The cut-off wheel cuts only along its edge. Do not attempt to sand or cut curved holes with them."

In the past I have used a finger gauge to mould the prop hub shape and then traced and transfered that shape onto a masking tape coated spinner using a pencil held as horizontal as possible, repeat of course 180 degrees for the other side - then hogged it out with a Dremel grinding stone and finished off with an old prop of the same type coated with wet and dry around the hub area to duplicate the correct shape.

Cheers.
Title: Re: PA51 Spinner
Post by: Luis Strufaldi on November 19, 2014, 03:23:52 AM
Luis, they sell a couple of different types of carbon spinner. If you get this one:  http://www.hobbyking.com/hobbyking/store/__25680__2_Inch_Carbon_Fiber_Spinner.html
the cone is held on with a couple of screws and you won't need an adapter.

Steve


Thanks Steve!
This one will work for the 2 blade prop, but not for the 3 blade, because of the position of the bolts.

I was planning on saving a few bucks, but this will most likely end up costing more in terms of man-hours to put everything together and aggravation than it's worth. Probably much better (and perhaps safer) to go with Steve Helmick's suggestion and go for the tried and thrusted Tru-Turn.

Thanks a lot to all of you guys that took the time to reply!
Title: Re: PA51 Spinner
Post by: RandySmith on November 19, 2014, 02:34:58 PM
HI

The PA 51 is an 8mm shaft with 5\16 x 24 threads, so you will need the spinner to have the ability to fit those dimensions

Regards
Randy
Title: Re: PA51 Spinner
Post by: Steve Helmick on November 20, 2014, 06:59:36 PM
"Probably much better (and perhaps safer) to go with Steve Helmick's suggestion and go for the tried and thrusted Tru-Turn."

What I was actually suggesting was to look at the Dave Brown, Tru-Turn, etc., spinner adapters and prop nut options. I have had to re-tap a brass Chinese (Magnum, I think) adapter to a suitable SAE thread...and then found out the screw head didn't fit into the counterbore in the tip of the spinner, so had to figure out how to open that up (glued the spinner to a chunk of aluminum that I machined a groove into to index the spinner cone, did my machining and the used the heat gun to make the epoxy release.)

Randy Smith's Aero-Spinners are my favorite, but come with an aluminum adapter...and I would be too worried about stripping the threads out. Maybe he makes steel adapters, but I dunno. I know he has some magnesium pieces, but I always seem to need nose weight.  H^^ Steve