Author Topic: RLE questions!  (Read 22516 times)

Offline Alyn Foundry

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Re: RLE questions!
« Reply #60 on: February 01, 2016, 07:51:51 PM »
Hi Jason.

Thanks for that.   :ThumbsUp:

I have to agree with Jo all the RLE's I built were done with BA. Here's a link on ebay for BA grub screws.

http://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2047675.m570.l1313.TR0.TRC0.H0.XBA+Grubscrew.TRS0&_nkw=BA+Grubscrew&_sacat=0

Kind regards, Graham.

Posts crossed again !! Jason has a point there, BSP for pipe work and Metric for sparkplugs.

Offline Manorfarmdenton

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Re: RLE questions!
« Reply #61 on: February 01, 2016, 10:41:54 PM »
I knew there would be some interesting input!  Thanks Jason for the chart and link, and Graham for the replies.

Jo, I know what you mean - makes sense!

In my full-sized fabrications I have gone all metric - M8, M10 and M12 for small stuff and M16 up to M30 for the larger studs and bolts.  Since the Red Wings originated in the US the threads are mostly UNF and UNC, and I used the ones supplied so had to spend quite a bit on little taps and dies.  As I now have them I thought I might as well use them.  For the model Best I went BA, apart from the wheel spokes which are M2  - they are bicycle spokes with the threads cut off, as they are made from 2mm round and there wasn't a BA equivalent.  Years ago I bought (from Reeves I think) a BA tap and die set, but its carbon steel.  One might as well try to tap a thread with a stick of liquorice!  So as I have needed them I have bought HSS taps from Cromwells - have a trade account with them and get a substantial discount.  As I'm making a Red Wing piston (no 4, so I know how to do it......I think) I thought I'd use Red Wing sized fixings.  I have just looked at my trusty Cromwells catalogue and see that they list the sizes I asked about for very little money, so I may go that way.  But not until I have looked at your suggestions.

John.
John Fearnley

Offline Manorfarmdenton

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Re: RLE questions!
« Reply #62 on: February 04, 2016, 12:52:40 PM »
The piston is finished.  Cromwells very obligingly gave me some 4 x 40 and 8 x 32 UNC grub screws as free samples (I didn't want the boxes of 200 that they came in).

The flywheels are done apart from finishing the centre holes and fitting the grub screws.

I'm still undecided about fitting main bearing bushes or not.  Graham, your comment has made me wonder whether to not bother!  One question, and probably a silly one, but why can't I use a magnetic switch in conjunction with a buzz coil?  Why is it different from the pick-up pin arrangement on the Red Wings?

John.
John Fearnley

Offline Alyn Foundry

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Re: RLE questions!
« Reply #63 on: February 04, 2016, 02:54:17 PM »
Hello John.

Questions noted, reply later, Grandpa duties, school run!! ;)

Kind regards, Graham.

Offline Roger B

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Re: RLE questions!
« Reply #64 on: February 04, 2016, 02:59:08 PM »
What do you mean by a magnetic switch, a reed switch or a hall sensor? A reed switch will probably work, a hall sensor will not carry the required current. This is why I built an amplifier module for my vertical engine (mentioned a few posts back).
Best regards

Roger

Offline Alyn Foundry

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Re: RLE questions!
« Reply #65 on: February 04, 2016, 06:07:12 PM »
Hello John.

My Robinson " X " type is now 27 years old, in fact it's retired from active service!!   ;)

The mains that run directly in the Cast Iron show imperceptible wear on the crankshaft, the crankpin however, is now down by 20+ thou. Using Bronze, unless copiously lubricated will actually wear the Steel rather than the Bronze. That's my personal experience.

Ok, how deep do we go here regarding contact makers? I'm fairly sure most readers here will be familiar with the term " Inductance ". Any multi turn coil wound on a " Ferromagnetic " core possesses it. One application well known is the Low Tension ignition systems fitted to many early stationary engines. When a voltage is applied to a coil, a current starts to flow, this in turn creates a magnetic field in the core. When the circuit is broken via a switch, contact breaker etc. the magnetic field rapidly collapses and generates a voltage that tries to maintain the circuit resulting in an arc  ( BEMF ). It's this arc that provided the energy to ignite the vapour within the cylinder, on LT ignition,  (Igniter type engines).

The Buzz box primary circuit is also highly inductive and would destroy the semi conductive switch that lies within a Hall sensor and IMO also very quickly weld the contacts of a Reed switch together.
There are ways to reduce arcing, placing a high voltage low capacitance capacitor across the breaker, placing a Diode ( one way electric valve ) to steer the voltage back.

Jason has used a circuit that effectively takes the rather feeble Hall switch to drive a semiconductor that's capable of handling the heavy current and high voltage spikes that the Buzz box generates.

Phew..... I hope this wasn't too technical ? Educational ?

Kind regards, Graham.

Offline Alyn Foundry

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Re: RLE questions!
« Reply #66 on: February 04, 2016, 06:09:55 PM »
Whilst on the RLE subject.....

Geoff from the Anson sent me this link.

http://pages.ebay.com/link/?nav=item.view&id=262271691893&alt=web

This ones looking for some TLC !! Poor thing !!

Cheers.

Offline Jasonb

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Re: RLE questions!
« Reply #67 on: February 04, 2016, 06:34:59 PM »
Jason has used a circuit that effectively takes the rather feeble Hall switch to drive a semiconductor that's capable of handling the heavy current and high voltage spikes that the Buzz box generates.

Not me, the engines that I have used a buzz coil on have metal to metal contacts just like the real thing. Most of teh hit & miss engines with CDi units I also tend to use contacts rather than hall sensors. The S/S ignitions can be tripped by either means

Offline Alyn Foundry

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Re: RLE questions!
« Reply #68 on: February 04, 2016, 06:56:01 PM »
What do you mean by a magnetic switch, a reed switch or a hall sensor? A reed switch will probably work, a hall sensor will not carry the required current. This is why I built an amplifier module for my vertical engine (mentioned a few posts back).

Hello Jason.

I was referring to your last sentence.

Kind regards, Graham.

Offline Jasonb

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Re: RLE questions!
« Reply #69 on: February 04, 2016, 07:09:42 PM »
Do you mean Roger B's post about the amplifier?

Offline Alyn Foundry

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Re: RLE questions!
« Reply #70 on: February 04, 2016, 07:28:43 PM »
Do you mean Roger B's post about the amplifier?

Oooh er........

Sorry Jason.... might be considered a senior moment?   :-[ 

Kind regards, Graham.

Offline Roger B

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Re: RLE questions!
« Reply #71 on: February 04, 2016, 07:44:57 PM »
It was indeed my post. It was based on the problems I was having trying to get an engine to run with a RCEXCEL CDI system. I had already installed Hall effect sensor but wanted to use a normal coil.

"This is the basis of the system that worked on my vertical engine, a Velleman K2543. I removed R2, Bridged R3 with a wire link and replaced R4 with a 220R resistor. I bought a Futaba servo extension cable, cut off the appropriate end to fit the Hall Effect Sensor and connected Red to 1 White to 2 and Black to 4. If this was not sufficient I would have bridged D2 as well. The coil was a Lucas replica 6V bike coil from Classic Bike Parts:

http://www.classicbikepartscheshire.com/electrical-c3/ignition-coils-ht-leads-c14/ignition-coil-6v-lucas-replacement-for-classic-motorcycle-p282

I used a piece of normal pvc flex for the HT lead (it can stand 20kV) short term.

This change from the CDI moved from a few vague pops to a start and run."
Best regards

Roger

Offline Manorfarmdenton

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Re: RLE questions!
« Reply #72 on: February 04, 2016, 07:53:33 PM »
Roger, I said I was hazy about it all  :)  I thought Hall sensors were reed switches.

Graham, thanks for the explanation.  I understand about the back emf......I think.  I was being lazy really, and hoping to modify the Red Wings to use a better contact breaker without having to alter the buzz coils that are in situ.  I'll try the little capacitors over the weekend and see what happens. 
Re. the mains, you're obviously right in that bushes aren't necessary.  I don't know why I keep soul-searching over using or not using them!  I have even started making larger cast iron bearing caps to accommodate them, but am still undecided!  A life-long failing of mine has been thinking too much! :( 
Re the Anson, I looked at the site but couldn't find any mention of Gardner engines.  Was I in the wrong place perhaps?

John.
John Fearnley

Offline Jasonb

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Re: RLE questions!
« Reply #73 on: February 04, 2016, 08:05:32 PM »
They used to list the Gardener in their "shop" section but that has not down for quite a while. I'm sure they would sell more if they made it a bit more obvious on the website particularly if they are now also going to have the Retlas available

Offline Manorfarmdenton

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Re: RLE questions!
« Reply #74 on: February 14, 2016, 01:03:24 PM »
Had another hour or two in the workshop and made some progress on the crank.  The webs are sitting in my crankshaft jig waiting for the Loctite on the silver steel crankpin to cure, then the two halves of the shaft itself (silver steel again) will be Loctited in and clamped in the vee blocks for curing, followed by taper pinning.  I made the two Red Wing crankshafts by this method and they seem to be fine several years later.  John.
John Fearnley