Author Topic: Fitting spinners (Read 4182 times)

Geoff Goodworth · « **on:** May 09, 2013, 09:29:12 PM »

I have a Brodak 40 in an Oriental. It's a new installation, replacing a Fox 35.

With a Dubro spinner backplate fitted, there is one one thread of the crankshaft exposed through the standard washer.

I replaced the nut and washer with a through the washer propeller adapter but the prop still comes loose.

How can I fix the problem?

bob whitney · « **Reply #1 on:** May 09, 2013, 10:20:07 PM »

dose the adapter go into the prop or just through the washer ,if it dosent go into the prop than a new longer adapter nrrds to be made to pick up more threads

Geoff Goodworth · « **Reply #2 on:** May 10, 2013, 05:10:27 AM »

Bob, the adaptor is much the same as others that I have seen and only fits into the washer.

I think what is needed is needed is a tube nut with a hex at one end.

Given that the props that are used on our wngines with 1/4-UNC threads are similar in thickness, I think there is a market for somebody with a lathe to supply those of us who don't.

EddyR · « **Reply #3 on:** May 10, 2013, 05:17:29 AM »

Use a Brodak metal spinner or some other with a thin backplate

Akihiro Danjo · « **Reply #4 on:** May 10, 2013, 10:30:23 AM »

How is this?
Aki

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXXF35&P=0

Brett Buck · « **Reply #5 on:** May 10, 2013, 11:06:24 AM »

Quote from: Akihiro Danjo on May 10, 2013, 10:30:23 AM

How is this?
Aki

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXXF35&P=0

That seems just about ideal, well done!

Brett

EddyR · « **Reply #6 on:** May 10, 2013, 01:20:42 PM »

This is the one I mentioned and ir comes with the adapter that you are looking for.
http://brodak.com/brodak-1-3-4-spinner-with-2-holes.html

Reptoid · « **Reply #7 on:** May 10, 2013, 09:10:30 PM »

Quote from: Akihiro Danjo on May 10, 2013, 10:30:23 AM

How is this?
Aki

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXXF35&P=0

I would contact Tower prior to ordering this for your Brodak. The item lists it as a 1/4"-28 thread but the technical desciption says it fits the 60 and lists the thread as 5/16"-24

. For the Brodak, you would want the 1/4"-28

Akihiro Danjo · « **Reply #8 on:** May 10, 2013, 10:52:22 PM »

Quote from: Reptoid on May 10, 2013, 09:10:30 PM

I would contact Tower prior to ordering this for your Brodak. The item lists it as a 1/4"-28 thread but the technical desciption says it fits the 60 and lists the thread as 5/16"-24 . For the Brodak, you would want the 1/4"-28

Reptoid san,
You are right and Tower's website is wrong.
OS stock# 73101010 is for 5/16" thread.
For the Brodak, you should order OS stock# 73101000, though Tower may not stock it.

Aki

Geoff Goodworth · « **Reply #9 on:** May 10, 2013, 10:57:56 PM »

Good call Don.

My thanks go to Akihiro Danjo for finding the part but I too, noted the technical comments. However, Akihiro set me searching—thanks again

Since I'm in Oz, I checked a recent OS catalogue at my local hobby shop and found that the Tower site is wrong in describing the long nut set OS Part Number 7310 1010, as 1/4" UNF. OS Part Number 7310 1010 is described on the Australian OS agent's web site as 5/16" UNF.

The OS catalogue that I checked this morning lists OS Part Number 7310 1000 as 1/4" UNF and the Australian agent's web site lists it as available so I've ordered a couple for delivery next week.

I searched the Tower site for OS Part Number 7310 1000—unsuccessfully—so I've written to Tower pointing out the error with their listing of OS Part Number 7310 1010 and suggesting that they should stock 7310 1000 as well.

We can only wait and see.

Geoff Goodworth · « **Reply #10 on:** May 10, 2013, 11:00:13 PM »

Thanks for the follow-up Aki. It's been an interesting mornning.

Steve Helmick · « **Reply #11 on:** May 11, 2013, 12:05:45 AM »

My solution is to simply avoid all spinners with plastic backplates. Perhaps you need the nose weight? On an Oriental? Seems unlikely! Most would need a light spinner, which suggests to me either a Brodak Aluminum spinner, a Randy Aero spinner, or the Great Planes nylon spinner with aluminum backplate (about $6.97 at Tower). I wish I could give a weight comparison, but can't at this time.

Steve

Duke.Johnson · « **Reply #12 on:** May 11, 2013, 10:58:22 AM »

Quote from: Steve Helmick on May 11, 2013, 12:05:45 AM

My solution is to simply avoid all spinners with plastic backplates. Perhaps you need the nose weight? On an Oriental? Seems unlikely! Most would need a light spinner, which suggests to me either a Brodak Aluminum spinner, a Randy Aero spinner, or the Great Planes nylon spinner with aluminum backplate (about $6.97 at Tower). I wish I could give a weight comparison, but can't at this time. Steve

Steve
Will the Great Planes come off with kick backs very easy? I've had that trouble lately.

Geoff Goodworth · « **Reply #13 on:** May 11, 2013, 06:44:01 PM »

Thanks for all the input. However, a few observations.

While the back of a Brodak spinner is almost flat, the 1 3/4" dia Brodak spinners that I have are about 0.030" thicker than the 2" Dubro item.

Since I was chasing small increments, a change of propeller—to the APC 10.5 x 4.5 that so many people recommended which arrived after I posted the question—and a change of prop washer—to a Tower 40 item—means that when fully tight, the prop nut is now flush with the end of the crankshaft.

The Great Planes spinner is worth trying but living in semi-rural New South Wales about 70 miles out of Sydney, I can only think of one possible retail source—and thanks to USPS, deliveries from Tower are a bit hit and miss.

For example, from east coast Australia to Tower in Illinois is about 1/3 of the way around the world. For some reson best known to themselves, last year, USPS sent all my Tower orders via Brussells—the long way!

Steve Thomas · « **Reply #14 on:** May 11, 2013, 07:27:33 PM »

Hey Geoff, I've got a few 1.75" Great Planes spinners sitting around in a drawer. If you want I can send you one, or give it to you at Coffs next month if you're there.

Steve

Steve Helmick · « **Reply #15 on:** May 11, 2013, 10:22:42 PM »

Quote from: Duke.Johnson on May 11, 2013, 10:58:22 AM

Steve
Will the Great Planes come off with kick backs very easy? I've had that trouble lately.

Well...ALL spinners will kick loose on occasion, but if you use the abbrasive discs provided, they GP spinners with aluminum backplates are pretty trustworthy. Their disadvantage is that they take a little fussing to get the prop/backplate timed right so that the cone/notches/screw holes converge properly. At least, the backplate doesn't compress, and isn't as thick as plastic ones.

I don't know what to say to console Geoff about the USPS. It is apparently one of the cheaper official goobermint postal services in this world, and I'm often shocked at how fast they can be, including from here to Oz. Perhaps your postal service is patterned after the Canadian's, where they are said to charge for storage?

Steve

Balsa Butcher · « **Reply #16 on:** May 12, 2013, 12:11:24 AM »

What Steve Says is true regarding the GP spinners. I'm currently using them on two planes that get flown a lot - one with an Aero-Tiger 36, the other an Enya XCS. No problems regarding loosening with kick-backs but a little fussy to get on sometimes.

Steve Thomas · « **Reply #17 on:** May 12, 2013, 01:58:04 AM »

Quote from: Steve Helmick on May 11, 2013, 10:22:42 PM

I don't know what to say to console Geoff about the USPS. It is apparently one of the cheaper official goobermint postal services in this world, and I'm often shocked at how fast they can be, including from here to Oz. Perhaps your postal service is patterned after the Canadian's, where they are said to charge for storage? Steve

Sadly I find that stuff takes consistently longer to come from the US than most other places. Anything from the UK takes a week or so, and if I get something from Ken Enya in Japan, it seems to arrive about 20 minutes after I order it (ok, 3 days then). Whereas from the US, it always seems to be a minimum of 10 to 14 days. No idea why.

Chris Wilson · « **Reply #18 on:** May 15, 2013, 07:48:35 PM »

How would increasing the thread length of the locking nut ever totally stop crushing a plastically distorting thick spinner back plate releasing the threads grip?

I am thinking that a thread locking system either in a liquid or a tape form might work out better here.

Steve Helmick · « **Reply #19 on:** May 16, 2013, 05:52:21 PM »

Chris, the problem is that with most engines, there's not enough crankshaft snout to get a full nut's worth of threads engaged. The OS (and Dave Brown) nut/washer sets help some with this. Getting rid of the squishy plastic backplate also helps keep the prop/spinner from coming loose on a kickback. The GP (aluminum backplate/nylon cone) spinners are quite popular, but they do only come in 2 blade versions. If you want to use a 3 blade, it is possible to use a DuBro 3 blade cone and install threaded holes to match, on the GP spinner backplate. Most guys change from the metric JIC screws to 4-40 socket heads. Whatever works, right?

Steve

Chris Wilson · « **Reply #20 on:** May 16, 2013, 06:08:00 PM »

Hi Steve,
I totally understand the issue mate but the original post tells me that the sleeve nut 'still' allows the prop to come loose - as in it did this previously and still does it after the use of a greater thread length.
This tells me that the solution was trying to kill two birds with one stone but whilst it definitely solves the lack of crankshaft thread it never will stop problem with the plastic back plate (as evidenced in post 1).

So either eliminate the crushing problem like you say (with an alloy spinner) or find some way to lock the thread 'if' that spinner is to be used.

Geoff Goodworth · « **Reply #21 on:** May 21, 2013, 08:03:58 PM »

OK guys, thanks everybody for the input. I did try the adapter nut from a Brodak spinner which extends through the front washer but it didn't work properly.

I have solved the problem temporarily by measuring props and prop washers to get reasonable thread engagement but I haven't been able to fly the model and try out the fix.

As a long-term fix, I think I'm going to have to make some adapter nuts like the Brodak and Dave Brown items but with longer threads to extend inside an enlarged hole inn the prop hub. Also, I will have to make something to suit the M5 thread on an FP10.

If I make my own, what grade alloy should I use?

Akihiro Danjo · « **Reply #22 on:** May 22, 2013, 06:53:49 AM »

Quote from: Geoff Goodworth on May 21, 2013, 08:03:58 PM

Also, I will have to make something to suit the M5 thread on an FP10.

Hi Geoff san,
What prop and spinner are you going to use with FP10?
This is my FP10 with Kyosho 7x4 prop and Goldberg 1-1/2" spinner. Perfect combo.

Aki

Geoff Goodworth · « **Reply #23 on:** May 22, 2013, 07:25:23 PM »

Spinners with the FP 10?

Aki, it will vary depending on the model but so far, a Dubro with an APC prop didn't give me enough thread engagement. I haven't seen Kyosho props in Australia.

But more interestingly, please tell me about the needle valve in the photo.

RandySmith · « **Reply #24 on:** May 22, 2013, 09:33:56 PM »

Quote from: Geoff Goodworth on May 21, 2013, 08:03:58 PM

OK guys, thanks everybody for the input. I did try the adapter nut from a Brodak spinner which extends through the front washer but it didn't work properly.

I have solved the problem temporarily by measuring props and prop washers to get reasonable thread engagement but I haven't been able to fly the model and try out the fix.

As a long-term fix, I think I'm going to have to make some adapter nuts like the Brodak and Dave Brown items but with longer threads to extend inside an enlarged hole inn the prop hub. Also, I will have to make something to suit the M5 thread on an FP10.

If I make my own, what grade alloy should I use?

Aluminum, use 2024, but you can also use a steel Fox or Tru Turn nut and tap the threads 1/4 x 28 all the way thru, I have done that with several spinner fitting, If you have access to a lathe it is very simple to size it too

Randy

Akihiro Danjo · « **Reply #25 on:** May 22, 2013, 10:25:57 PM »

Quote from: Geoff Goodworth on May 22, 2013, 07:25:23 PM

Spinners with the FP 10?

Aki, it will vary depending on the model but so far, a Dubro with an APC prop didn't give me enough thread engagement. I haven't seen Kyosho props in Australia.

But more interestingly, please tell me about the needle valve in the photo.

I checked my Dubro plastic spinner and found the backplate was thicker than Goldberg.
If you want to use Dubro's, you may need this:

https://cs206.xbit.jp/~w041133/store13/index.php?main_page=product_info&cPath=2_17&products_id=371

The needle is MVVS short. (The silver nut is borrowed from OS needle)
MVVS spray bar is 4.0mm dia and it is thicker than the one for OS FP10.
Original OS venturi was too large, so I use 4.0mm bar.
It is still powerfull and eats lots of fuel with it.
Aki

Geoff Goodworth · « **Reply #26 on:** May 22, 2013, 11:03:43 PM »

Thanks once again Aki. I will definietely explore that option.