Author Topic: Retlas  (Read 52837 times)

Offline Chipmaster

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Re: Retlas
« Reply #360 on: November 26, 2018, 08:10:06 PM »
Ok Jason, I’ve just viewed your earlier post on my ipad and magnified the images so I can now see your point.
Thanks
Andy

Offline Chipmaster

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Re: Retlas
« Reply #361 on: November 28, 2018, 07:08:54 PM »
There is run out on the Retlas half time gear., perhaps as much as 15 thou according to a plunger dial test indicator against the revolving gear teeth. Unfortunately after testing for barely a minute we had a power cut yesterday afternoon that lasted until 9pm preventing all model engineering activity. Had domestic commitments today but will dismantle the timing gears tomorrow to see whether I can salvage them or simply replace.
Andy

Offline Alyn Foundry

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Re: Retlas
« Reply #362 on: November 28, 2018, 07:35:50 PM »
Hi Andy.

Fifteen thou is a lot! That would, most certainly account for the noise.

In the absence of " soft jaws " ....

Perhaps a jig could be made by placing a piece of billet at oversize to the gear, boring it out to the gears OD and use a screw to secure it so the bore can be oversized and bushed?

Cheers Graham.

Offline Jasonb

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Re: Retlas
« Reply #363 on: November 28, 2018, 07:43:00 PM »
60 T gear could be held in a 4 jaw on every 15th tooth.and clock the tips of the teeth.

Offline Chipmaster

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Re: Retlas
« Reply #364 on: November 29, 2018, 06:24:31 PM »
I dismantled the timing gears and measured them this afternoon. The carefully measured run out of the 60 tooth gear was 0.0045” (4.5 thou) and 0.0005” for the 30 tooth gear, much less than I previously thought. It seemed worth making a replacement ‘eccentric’ axle for the 60 tooth half time gear with a greater throw to bring the gears much closer together.
After putting the engine back together with the new axle the whine had disappeared at cranking speed.  :cartwheel:
It’s our club meeting (Black Country Live Steamers) tonight so I haven’t time to fire the engine up this evening, hopefully will get it running quietly tomorrow.
Andy

Offline Chipmaster

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Re: Retlas
« Reply #365 on: November 30, 2018, 07:45:48 PM »
Retlas running with the whine from the timing gears almost eliminated so the problem was caused by excessive backlash.


The gas supply and ignition are still jury rigged...and the white silicone hoses are temporary until black tubing is delivered.

Andy

Offline Jo

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Re: Retlas
« Reply #366 on: November 30, 2018, 08:06:46 PM »
Nice  :)


At this point I feel the need to remind the members about the dangers of running engines in an enclosed workshop space  :slap: the Carbon monoxide given out by an IC engine can prove a killer. I know of at least one model engineer who died that way  :(

Jo
Usus est optimum magister

Offline Jasonb

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Re: Retlas
« Reply #367 on: November 30, 2018, 08:11:48 PM »
That sounds so much better Andy, no risk of anyone thinking there is an air raid due

Offline Alyn Foundry

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Re: Retlas
« Reply #368 on: November 30, 2018, 08:21:14 PM »



    :)   SUPERB    :)

Offline yogi

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Re: Retlas
« Reply #369 on: November 30, 2018, 08:27:00 PM »
Beautiful running engine Andy!  :ThumbsUp: :ThumbsUp: :ThumbsUp:

Offline Chipmaster

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Re: Retlas
« Reply #370 on: November 30, 2018, 08:28:16 PM »
I feel the need to point out that I have a carbon monoxide alarm in my garage. The garage also has a side door which is left open for these test runs and the engine exhaust is fitted with a long metallic flexible exhaust tubing directed out the door. The tubing is made locally in Redditch by Whitehouse Flexible Tubing which other readers might find useful  ( https://www.flexible-tubing.com/ ). I also limit my test runs to a few minutes.
Andy

Offline Chipmaster

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Re: Retlas
« Reply #371 on: November 30, 2018, 08:47:09 PM »
Thank you very much Graham, Jason, Jo, Yogi and Thomas. Now I’ve sorted out that awful whining noise I will finish the fine tuning and details. I still reckon the engine could run slower.
I have found that my engine runs better if the gas is supplied via a demand valve so I’ll make the valve a permanent fitting. I also intend to fit a push / pull switch for the ignition, in effect a ‘kill switch’.
Regards
Andy

Online zeeprogrammer

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Re: Retlas
« Reply #372 on: November 30, 2018, 10:34:47 PM »
I feel the need to point out that I have a carbon monoxide alarm in my garage.

Thanks for the reminder. I have that in my basement near the furnace but after renovating and adding an additional furnace in the new garage...I need to add sensors to the garage.

Nice running engine!
Carl (aka Zee) Will sometimes respond to 'hey' but never 'hey you'.
"To work. To work."
Zee-Another Thread Trasher.

Offline RayW

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Re: Retlas
« Reply #373 on: December 01, 2018, 04:20:35 PM »
That sounds just great now Andy, and so even running. Well done.
Ray

Offline Art K

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Re: Retlas
« Reply #374 on: December 01, 2018, 05:32:40 PM »
Andy,
I was up last night unable to sleep and watched the video. That engine purrs like a kitten, sounds great.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King