Making TD 0.020 Snap Starter Spring

dankar04 wrote:You could try a hardware store that sells ready made springs and modify. My local ACE srore has many different types and sizes. I don't think you will have much luck making your own but again I have no idea of what you can do. It very well may be easy to make one. TD .020 is easy engine to start and never use spring but keep them to have complete engines. The real problem is ends to fit around pressure fitting and blade end. Have fun.

Thanks Danker but have made springs before, and pretty confident I can make
one/them just need the dimensions. Please?? John

Wire is .028 thous. 6 coils and diameter of spring is 1/2" Coil length 3/16" all USA sizes stated.

Thanks Danker much appreciated, reaching for my mike, what better
way to spend a cold wet day in Scotland. John

Great sunsine here in Tucson should hit around 90* today, wind calm and clear. Just flew my new Heli outside and good flight. Solo Pro 328 4ch. Fixed Pitch. Good luck with project.
Cheers,Dan

dankar04 wrote:Great sunsine here in Tucson should hit around 90* today, wind calm and clear. Just flew my new Heli outside and good flight. Solo Pro 328 4ch. Fixed Pitch. Good luck with project.
Cheers,Dan

I hate you Dan
Take a look at day 15 of our moistness
http://www.windfinder.com/forecast/london_city_airport

John If it were me I'd get a PeeWee spring and have a play wth some needle nose pliers.
The PeeWee gauge is bigger but a man of your caLIBer should be able to work it out.

BTW
In my (very limited) experience I think the TD020 is THE motor that most benefits from a spring.

Checked my wire supply and discovered that 0.028 thou wire
is actually good old British 22swg but doubtless made in good
old Chicago Il. Made a little tool and wound first one on my
lathe, too big in diameter, so smaller mandrel and wound second
one, Perfect diameter, beautifully formed, just the eye and
hook to form. Bu---r me if it isn't a left hand wind.
At this point I was called for my tea and a couple of soothing
drams. Tomorrow is another day. John

proctor wrote:Checked my wire supply and discovered that 0.028 thou wire
is actually good old British 22swg but doubtless made in good
old Chicago Il. Made a little tool and wound first one on my
lathe, too big in diameter, so smaller mandrel and wound second
one, Perfect diameter, beautifully formed, just the eye and
hook to form. Bu---r me if it isn't a left hand wind.
At this point I was called for my tea and a couple of soothing
drams. Tomorrow is another day. John

John, Too bad there are no LH cranks for it. If there were, you
could rack your brains trying to find a 4.5 x 2 lefty prop.
Sounds like you're on to something though. Carry on.
Bob

Thought about making some .010 ones a while back. I had a hard time finding spring steel wire also I was wondering how to make the coils as I would need some serious tension to do it. The wrappings would have to be wound smaller than the correct diameter so they wpuld spring back to the correct size when loosened.

Piano wire will work for making these springs. k&S sells piano wire. Most hardware stores worth their salt will stock piano wire.

The coils can be made on a lathe or with a simple hand tool.

http://brodak.com/k-and-s-mighty-wire-bender-coil-winder.html

A tool like in the link above can be made to work with smaller diameter wire.

Jason

Hi Jason,
Most if not all of our piano wire is from K&S ( Chicago), as you know it
is a high carbon steel that has been hardened and tempered Back in my
toolroom days we made springs from high carbon steel wire, in soft
unhardened state then hardened and tempered. Easy, peasey but
heat treatment was a fiddle to get just the correct toughness.
Piano wire is perfect for the job but you need to heat in an oven
when finished for about 1 1/2 hours at max temp, about 470 deg
to stress relieve. The spring actually gets marginally smaller after
this treatment. Winding is easy and quick but think it might be
advisable to heat and let cool ends to soften for forming eye
and hook. But a perfect flying day here and I am off to Maiden
Matchstick. BTW our hardware stores are unfortunately not like
yours, I have to get my wire mail order. John

Shocked and stunned to hear you
Partake in that 'awful' stuff they make near
The Spey John...

Day 18 of the blasted rain/no flying so
I'll dig out a PW spring, bung it on a Td
And take a snap so you'll see how much easier it
Might be.
J

If you get one made please let me know how well it worked because I may need to make one for my AE .2cc soon.

If anyone needs assistance getting wire please send me a message. I know a few suppliers who have it if you cannot find it at a local store.

Regards, Matt

The strangest thing.......
I just took the Caliper to my springs and what I guess most of us know as a PeeWee
spring is 40 thou. The TeeDee is 30 Thou.
But I've just dug out Catalogue No 332 .020 Snap Starter which has a Hex type cam
(a'la Sure start or Texaco) which is only 25 thou the same as the 010.

I'm going to keep quite about fitting PW springs to TD's in future cos the coil on a PW is 12mm whilst
the TD is 13mm.
Doh

John Goddard wrote:I'm going to keep quite about fitting PW springs to TD's in future cos the coil on a PW is 12mm whilst
the TD is 13mm.
Doh

lol I figured that when I got my second ever cox engine
I ordered pee wee springs for my tee dee thinking to modify them but no fitty.

Aaaaaah
But have you ever seen a hex drive plate on a PeeWee?

John Goddard wrote:Aaaaaah
But have you ever seen a hex drive plate on a PeeWee?

Yes
http://www.selecthobbies.com/eginesdata.htm

I don't see it.
But Man does that GP07 look like the answer to the O/T's rise of ground challenge.......

John Goddard wrote:I don't see it.
But Man does that GP07 look like the answer to the O/T's rise of ground challenge.......

Get a mils 1.3cc, it will be perfect.

Flying followed by a bit of trout fishing today so no time to
make a proper spring. Thought I would post a picture of my
abhortive left hand one to show how easy they are to
make. Also shown end of short piece of piano wire that
has been heated to red heat and allowed to cool in air.
Makes it easy to form eye for round pressure take off.
Pliers small round nose jobs my daughter bought for
jewelery making.


https://i.servimg.com/u/f46/17/26/04/06/spring10.jpg

John

proctor wrote:Flying followed by a bit of trout fishing today so no time to
make a proper spring. Thought I would post a picture of my
abhortive left hand one to show how easy they are to
make. Also shown end of short piece of piano wire that
has been heated to red heat and allowed to cool in air.
Makes it easy to form eye for round pressure take off.
Pliers small round nose jobs my daughter bought for
jewelery making.


https://i.servimg.com/u/f46/17/26/04/06/spring10.jpg

John

man that looks great man

Got round to making a spring to night, is it perfect ?, no. Did it start my
TD 0.020 ?, yes.
Learned a lot though, spring I wound earlier was wound on 10mm
mandrel. (Drill bit, wound on shank) It was about 2mm large on diameter.
Used an 8mm drill tonight and finished coil was 9/16" instead of required
1/2", this is not good, better too big than too small or coils bind up
when you backwind.
Heated end that goes on press nipple to red heat and let cool, formed
eye for round nipple. You must wind this little loop in correct direction,
anti-clockwise, for it to fit over properly and tighten it's grip when
you backwind. At the other end, bit that hooks prop, heat only the
end 3/8" to make little loop, you need spring to remain in rest to retract
after it does it's work. My crude effort on left TD 0.010 on right John
Photo https://i.servimg.com/u/f46/17/26/04/06/spring11.jpg