Rina and T&K drawings

[Graham BirdParticipant @grahambird65048]

test

Edited By David Clark 1 on 27/11/2010 15:43:37

[Graham BirdParticipant @grahambird65048]

hi  james

I am about to make the fiddly bits on the rina governor the dimension from the centre of the bob weight to pivot hole centre on the drawing is given as1.00 inch could you verify if this dimension is correct. please

regards graham.

Edited By David Clark 1 on 27/11/2010 15:42:59

[David Clark 13Participant @davidclark13]

Hi Graham

If you must paste from Word, please use the paste button with the blue W on it.

See edit panel below for position.

regards david

 

[james service 2Participant @jamesservice2]

Hi Graham

 

My drawings show the pivot holes are 1 inch from the outer edge of the weights. As these are a 1/4 inch diameter, the dimension should be 7/8 inch.

 

Under normal circumstances, I’d measure this on the model before replying, but I am snowed in at the moment – probably for the next few days, so I am unable to get to the workshop.

 

Suggest you assemble the governor levers as in photo no 45 pg 323 in 4386 and fit the weights so as to just clear the face of the flywheel.

 

Regards

 

Jim

Edited By james service 2 on 28/11/2010 17:44:31

Edited By james service 2 on 28/11/2010 17:46:14

[Donald WilliamsonParticipant @donaldwilliamson36047]

Hi all, I have been following the banter on the Rena and have read all the article with a mind to make it my next project .  I am wondering why there is no reference to valve timing. Can you help?

Donald Williamson.

[Graham BirdParticipant @grahambird65048]

hi james

can you give me the rocker heght to pivot hole

also over all length of valves

and details of caps on valve springs

all the best graham

[Norman VantParticipant @normanvant32224]

Hello All,

 

I am currently making the body of the Rina and having bored the main bearing hole in the plates I’m about to drill the hole for the cam mounting shaft and looking ahead a little. To me the drawing of the Cam Mounting Shaft and Bushing (p165, fig. 17) makes no dimensional sense.

 

The drawing doesn’t even seem to be to scale, so setting about it with a pair of dividers isn’t much help either. Has anyone else noticed this, or is it just me in need of a new pair of glasses?

 

As it’s my first I.C. engine I’m not really comfortable making it up as I go along.

 

Regards,

 

Norman.

 

 

 

 

[JasonBModerator @jasonb]

No its not a very good drawing.

 

Missing dimensions, wrong dimensions (2BA thread onto 5/16″ shaft) and you can’t take a guess at some of the sizes as you don’t know what size the hole in the gear should be as the other drawing does not show it with a hole!!

 

 

I would hazzard a guess that the smaller dia of teh bush should be 1/4″ and the hole 3/16″. The plain part of the 2BA thread should be 3/16″ The slot width should be obtainable from the arm that fits into it and likewise the pin.

 

Jason

 

[Norman VantParticipant @normanvant32224]

Thanks Jason.

 

At least that confirms that it’s not just me losing my grip! Perhaps the drawing should have had a footnote saying, “All Dimensions er… Just guess”.

 

Regards,

 

Norman.

[David Clark 13Participant @davidclark13]

Hi There

Should be 3/16 as that is the od of the 2 BA thread as near as makes no difference

The gear will be a 1/4 inch bore as it obviously runs on the 1/4 inch diameter of the shaft.

The latchout lever is 3/32 inch thick so that covers the slot.

The pin through the assembly can be what you like, not really important as long as it is not to small in diameter. I would probably use a 5ba thread on a 1/8 shaft.

regards David

Edited By David Clark 1 on 13/06/2011 16:29:50

[Jim GreetheadParticipant @jimgreethead]

I have finally completed the drawings for a metric version of Jim Service’s RINA with a few simplifications to accommodate my limited skills (I hope Jim will forgive me) and now I have commenced construction.

 

But I still have (at least) one problem: I can’t find any information about the type of fuel (gas) used, or the construction of the fuel tank or the connection from the carburettor to the tank. Could someone please point me in the right direction?

 

Thanks to the good advice from John Olsen, I have completed the drawings in Alibre – certainly the quickest, easiest and cheapest way to produce 2D drawings and you get 3D images and assemblies into the bargain. My copies of AutoCAD, DesignCAD and TurboCAD are now only used to retrieve drawings that I made in the past.

 

I am happy to provide copies of my drawings to anyone who asks for them (I hope I can do that without doing anything illegal). You can have them in Alibre, .pdf or .dxf.

 

As I work my way through, I am finding some dimensions missing but you are welcome to them as they are if you are in a hurry or later on (after Xmas at least) if you want the corrected set with the errors minimised (they are never absolutely correct).

 

Jim

 

[JasonBModerator @jasonb]

For fuel you can use regular unleaded or the cooler burning Colemans fuel that can be had from camping supplies as its used for stoves.

 

You may want to ad some WD40 to the mix to help lub teh valve and piston to some extent, use the liquid type not spray.

 

A small fuel tank can be made with a bit of copper or brass tube with ends soldered on or a “box” tank made to fit withing the engine base. I would suggest to start you use a temporary tank to find out what level it needs to be at to stop flooding/run back as unlike a Lukenheimer type carb there is no non return valve.

 

My preference for plumbing hit & miss engines is to use the scale malable fittings and threaded copper pipe but paint it so it looks like gas barrel – this sort of thing

 

J

[Jim GreetheadParticipant @jimgreethead]

Thanks Jason, those fittings look quite the thing don’t they. And what is the engine? It looks a good one too.

 

Rina is supposed to be gas powered and therein lies the problem. We got the drawings for the gas carby (and another beautiful one in Alibre from John Olsen) and I have made that. But there is no indication of the fittings, fuel or tank for the gas supply.

 

If I can’t find a solution, I will convert it to one of Jan Ridders’ vapour carbys which, I suppose are a form of gas carby with the gas being the vapour under ambient pressure which dispenses with the demand valve section. And I will certainly use Coleman fuel as I do in the Debbie two stroke http://www.youtube.com/watch?v=o-zo52flDbI

 

Jim

 

 

 

[JasonBModerator @jasonb]

Ah for gas you can use the butane camping gas or propane and fill a small tank with that. Bruce engineering do the valves and tanks but if Bogstandard does not add a reply I’ll dig out a post of his on makinmg tanks, they do need testing to about 300psi.

 

Not sure of your carb but with gas on a hit and miss engine you really need a demand regulator so the gas does not flow when it’s missing, there is a design here

 

The pipe fittings come unmachined from PM Research in the states but Forest Classics may now be doing them as they do some of their engine kits.

 

The model is a 1/5th scale IHC Famous Vertical screen cooled, I’ve posted the build on HMEM

 

J

[Jim GreetheadParticipant @jimgreethead]

Thanks Jason,

 

Now we are cooking with gas (so to speak). I understand the demand regulator and I like the idea of making a block to run several engines. That will come later. The one shown is similar to one that I got from Model Engine Builder using the Tecumseh kit which seems very popular and which included the jets. I have already constructed the demand regulator and carby shown with the RINA drawingsand it is much smaller so I will start with that one (if it works and if it seals properly).

 

I was smiled upon by an normally malevolent spirit which guided me to the GasMate BBQ spares when I was looking for something else in the hardware store. And there I found a 2.75kpa (1.45 psi) regulator with POL fitting to go on a LPG bottle. Just the thing. I won’t need to make a fuel tank, just connect to the big bottle. But thanks for the offer of a design. Testing something I made to 300 psi was a bit of a worry so I am please to avoid it.

 

Forest Classics (I had not previously heard of them) seem to have the fittings as you suggested.

 

And your HMEM build of the IHC Famous gave me a big injection of humility. I still have heaps to learn and I learned a lot from your photos. Great work and thanks for sharing.

 

Jim

 

[Norman VantParticipant @normanvant32224]

Hello again,

 

Since starting this build, there has been one issue which I have repeatedly kicked into the long grass and got on with something else. Now there is no escape!

 

I would be interested to know if and how others have made the governor bracket as drawn and described in the build notes. I have got as far as making the blank, disc with 1/4″ bar silver soldered across. It appears to me that, whatever machining sequence is then followed to cut the slots, you end up with something too weak to hold or machine.

 

Any suggestions would be greatly appreciated.

 

Regards,

 

Norman.

[JasonBModerator @jasonb]

Rather than solder the square bar to a disc, solder it to the end of a bit of round bar. That way you have something substantial to hold while the slots are milled and holes drilled. Once all is done put it in the lathe and part off the disk with brackets attached.

 

J

[Jim GreetheadParticipant @jimgreethead]

Norman,

This is how Metalbutcher cut it out of a solid block of aluminium and I intend to copy his example.

 

http://www.homemodelenginemachinist.com/index.php?topic=11257.msg130233#msg130233

 

Because I am using a flywheel without spokes, I increased the size of the disk on the governor bracket to 38mm diameter to make it a bit more solid.

 

This thread on HMEM has provided me with lots of good ideas and some much-needed inspiration to consider dud bits as “practice” and keep going.

 

It is nice to know that someone else is building Rina, I thought I might be the only one. Good luck and how about some photos of progress to date.

 

Jim

 

[Norman VantParticipant @normanvant32224]

Jason and Jim,

 

Thanks for the replies.

 

Jason, Did you do it that way? The difficulty seems to be the same, either way. Once the cross slotting is done, in either order, the soldering area is minute. I can see the endmill returning it to kit form! I’ll give it a try though, and let you know how I get on.

 

Jim, Yes, someone else is building the Rina but it’s touch and go. It comes so close to the scrap bin, daily. What I have done so far is OK but it’s been a struggle all the way because every minor part (minor but important) has been so poorly dimensioned. If you know how a thing is assembled you can infer the dimensions. If you know the dimensions you can infer how it’s assembled. If you don’t know either… It can only be described a stoicism in action.

 

Yes, I like the idea of hacking it out of the solid and I might try that if all else fails.

 

Thanks and regards,

 

Norman.

[Jim GreetheadParticipant @jimgreethead]

Hi Norman,

 

In regard to the dimensioning, John Olsen has redrawn the whole engine in Alibre and I can send the files to you if you wish. Alibre is a 3D CAD program that John convinced me is the simplest and cheapest way to produce 2D drawings. You can download the full program on trial for 30 days for free and the Personal Edition (that I use) is $199. It took me about 1 week to become reasonable proficient in using it and less to do simple things like producing dimensioned 2D drawing from the 3D parts. I can recommend it.

 

I have redrawn the engine (using Alibre) converting the imperial measurements to rational metric including metric threads. I have also modified it a bit to suit my limited capabilities and natural disinclination to file complex shapes when I can cut stuff with a slitting saw.

 

In producing my version I have, in parts, been too clever by half with the result that I have had to backtrack and revise my design several times. But that is life I guess.

 

Send me an email to greethead@hotmail.com if you would like the files. If you would like to talk, my Skype address is jimgreethead.

 

Jim

 

Edited By Jim Greethead on 20/12/2011 06:30:21

[Norman VantParticipant @normanvant32224]

Jim,

 

That’s a very kind offer. If I were starting again, I would have your hand off. However there are few parts left to make now and I’m afraid I work in “irrational” measurements (except for fasteners). Certainly, John Olsen’s contribution to this thread has been an immense help, particularly the GA drawings. Many thanks to him. Just wish I’d discovered them earlier on in the proceedings.

 

At the moment I’m attempting to cut the governor bracked from the original blank, as drawn. It would be a pity not to try, having made it. I’ve done the long slot down the arms with baby cuts and it is still hanging together. Fingers crossed on the next cut, across. If the expected happens, I’ll make one of a larger diameter, as per your suggestion. Yours is more likely to stand up to use, too.

 

Unfortunately decorating duties have intervened for today, and possibly longer, but I’ll let you know how I get on and hopefully provide some photos of progress so far.

 

Regards,

 

Norman.

[Norman VantParticipant @normanvant32224]

Jim,

 

No photos yet. Come to think of it, they would be pretty uninspiring anyway, just a set of components that look approximately the way they should.

 

The dreaded governor bracket is done. My only deviation was to take the wide slot out with a junior hacksaw VERY carefully rather than mill it out. It seems to be holding up with the very small soldering area remaining.

 

The current state of play is that I’m filling up my “springs-that-might-be-useful-one-day” box. My best attempt for the governor springs so far is 0.010″ wire wound on a 1/8″ mandrel. The weights do fly out but at a higher speed than I would like when spun on the lathe. 0.007 might be better but my effort with that ended up as a rat’s nest! What did you use? Or was it something out of the aforesaid box, of unknown spec.? I might yet unsolder the weights and use heavier ones. That should make the springing less critical, I think.

 

Getting there, I suppose, but this is a very fiddly bit.

 

 

Regards,

 

Norman.

[Jim GreetheadParticipant @jimgreethead]

Well done Norman, you are way in front of me. I have struck one of those mental blocks exacerbated by having too many projects. The result is that I spend all my time swapping projects and none actually getting something done.

 

In multi-tasking operating systems (like Windows) it is called “thrashing” – a very apt term. So I need either to close some jobs or increase the time-slice allowed for each.

 

I am also making a few changes (apart from the metric conversion) to accommodate my limited skills and material on hand. Latest change is to a roller cam follower which might end up in the scrap bin along with quite a few other ideas that seemed good at the time.

 

But it keeps the days apart and is more interesting than watching the TV.

 

If you are playing with the governor springs, I guess we are getting close to cigars all round. Please keep me informed.

 

Jim

 

[Norman VantParticipant @normanvant32224]

Jim,

 

Seems to me that there is quite a way to go yet before the King Edwards can be broken out: getting the governor sorted out and fitted – not just with one flywheel on the lathe; carb, for petrol rather than gas and the ignition. Ah, yes. The ignition. Not much help from the drawings or build noted there.

 

My spring winding skills are improving but I can’t seem to guess, in advance, what will give the appropriate rate and extension. So many variables. Not quite there yet. Score of trial and error are exactly equal, at the moment.

 

Your idea of a roller cam sounds good to me. I contemplated that but thought I’d try it as drawn first. The problem I encountered was the “harshness” of the initial lift. It seemed to display a preference for bending the pushrod – long overhang plus flat, rather than sliding contact. I got over it by softening the cam profile, and that of the follower, a bit. Just about OK now. I think a roller is the way. My only objection to that is that I hate re-making parts if I can avoid it. Let us know how you get on if you try the roller.

 

If anyone else has made the governor springs, advice on gauge and mandrel size for the best performance would be most welcome.

 

Regards,

 

Norman.

[Jim GreetheadParticipant @jimgreethead]

Hi Norman,

 

The ignition is another thing that I have changed. I intend to use the same arrangement that I have used on my two previous engines. It is based on an RCEXL CDI similar to the one recommended at the end of the ME articles.

 

Instead of all the cutouts around the 40T gear, I have cut a channel into the side plate on the other side as shown in the photo in my album. The channel will contain the hall effect device and the wiring leading to it.

 

The magnet will be glued into a ring attached to the crankshaft by a grubscrew to allow it to be rotated to adjust the timing.

 

The CDI and a battery box containing 4xAA rechargeable cells are attached to the underside of the base plate. Sorry I can’t show you on this forum because I can only upload jpg files and Alibre CAD produces pdf. Maybe if we used HMEM we could do it.

 

Anyway, that works for the other engines. Of course it will fire every stroke but that is no problem, the same thing happens on my Triumph.

 

If you would like the pdf, send me an email and I will reply to it.

 

And I note that you intend to use petrol. I have built the gas demand valve but I don’t think I will use it. Instead, I will use one of Jan Ridders’ vapour carbs. They are simple and they work ok.

 

Jim

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