Shaft Extension?

[Serge_Krauss]

'not sure whether this belongs in the engine section, but here's my question.

Is there a reasonable way to get the old Fox .15/.15X to accept a spinner? I was all ready to finish contouring the nose of my "Peacemaker" to align with a 1 3/4" spinner, when I discovered that the shaft isn't long enough to accommodate the spinner back plate, prop, nut, and washer. Before I taper and/or round off the nose to better work with the prop minus spinner, I thought I'd ask whether I'm missing something obvious here. The plane has a hefty tripler on the left to calm the Fox vibrations. It too needs tapering. Shall I just go ahead and make the thing ugly? Thanks.

[Kim Doherty]

Hi Serge,

Yes there is a simple fix but it requires a metal lathe. Bore the prop over size to accommodate a "T" nut (think a regular blind nut without the spikes and a longer threaded portion) There is plenty of thread inside the prop. Note that you do not want to bore the whole depth of the prop hub. Leave enough to center the prop on the shaft.  You will need to machine the nut to fit the bore and thread it. If you just need a couple of threads then you can chuck up the original steel nut and machine the back side to fit the new bore. I have done this to fit spinners many times.

The pictures show the basic principle. In this case the the nut was buried in the drive washer. No difference if it needs to go into the prop hub, just make a nut with a longer shaft.


Kim.

[Tim Wescott]

What Kim said.  It looks like you've got an APC prop on there so you don't even need to bore out the front of the prop.

I did this on a plane that I inherited: whatever engine had been on there was longer from bolt to prop drive than the engine I put in, so I made a spacer and then didn't have enough threads.  I took a 3/8" bolt, drilled & tapped it for 1/4-28 (on a lathe -- this isn't something you can do accurately enough on a drill press), made a washer to match, and it's worked great for several dozen flights.  The OD of the nuts fits into the APC prop that I use, and all is well.

If you don't have access to machine tools and can't get it done locally, check with Jim Lee -- I'm sure he can get you set up for not too many $$.  I've seen some engines that come stock with a nut like that, but I couldn't name a brand beyond the well-respected Maybe-Saito.

[RandySmith]

many nut for prop shaft extension will  work to do this for you, if you have a box of them from over the years  you may want to go thru them
Or  if you have a lathe  as they said  make one

Randy

[Norm Furutani]

It would look like this: http://www.gravesrc.com/supertigre-prop-nut-g-2300.html
Don't think you will find a stock item that will fit a .15 Fox. As mentioned, you need someone with a lathe.

Norm

[Curt D Contrata]

http://www.gravesrc.com/supertigre-prop-nut-g-2300.html

And, if ever in Orlando, Graves RC is a must. Great Hobby Shop, a rare treat.

Curt

[Ken Burdick]

you should be able to buy an "extension nut" at McMaster Carr, possibly tower hobbies. Aluminum will work well and dubro may have it so check online hobby dealers.

[Norm Furutani]

A bit off topic, but a cool step by step on how to make a prop extension. http://www.fineworks.tw/modules/xforum/viewtopic.php?forum=14&topic_id=187&order=

Norm

[James Lee]

Serge
Check your email..
Jim

[GERALD WIMMER]

This should do the trick :
http://www.ebay.com/itm/60401-FOX-10-32-SHORT-ADAPTER-NUT-ONLY-ENGINE-PART-CONTROL-LINE-/252384232605?hash=item3ac345c49d:g:izYAAOSwInxXMPCG
Mecoa may have the longer 10-32 extensions too.
Regards Gerald

[M Spencer]

I THOUGHT FOX 15s WERE  BANNED ! . 



Ive used a Fox 3/4 Extn Nut on the !/2 in Extn Spacer on occasion ,
or just such a nut , if ye dinnae need  the spinner backplate fwd .

[Serge_Krauss]

Fantastic! Thanks guys! I learned something from your posts. Jim has e-mailed me that he has what I need.

[Steve Helmick]

An aluminum spinner backplate will help the situation a lot. Plastic spinners are not a bad thing, but plastic spinner backplates are always a problem in shaft thread lengths and also prop slippage. I'd suggest this one. Pretty affordable, various colors, run true, nice, and often used even on "serious" stunt models. Check with Dave Brown Products for the nut/washer parts you need. See MA ads.  Steve

https://www.towerhobbies.com/cgi-bin/wti0001p?&I=LXBMX8&P=0