Author Topic: Retlas  (Read 67842 times)

Online Chipmaster

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Re: Retlas
« Reply #60 on: February 01, 2016, 04:50:20 PM »
Keyways:
Graham, reckon a 3/8" key might be a typo?
Anyway I had the 3/16" keyways done well in advance early last December, a picture of the gear is included below.
My friend Brian broached the keyways in the flywheel and timing gear using his Jones & Shipman press with a set of imperial broaches that included a variety of bushes, tables and shims. We double checked the spec using a Machinery's Handbook. The broach was pushed right through so there's no taper in the hub. It only took about ten minutes to broach both the flywheel and timing gear.

I chose to leave the Retlas flywheel hub pretty deep - almost 2". For smaller engines I have formed keyways by mounting the flywheel on the lathe and  forcing through the appropriate shaped tool mounted in a boring bar. However, there's no way I could achieve a decent result on a hub 2" deep. It's tough on the lathe so I wouldn't go back to that method, I recommend making friends with someone who owns the proper broaching kit which gives a far superior result.

Jason - I have also used rectangular key steel for the same reason, and with micrometer blue. That stuff is incredibly messy! The tin I'm using was given to me by a retired engineer and is probably over 50 years old with 75% still left in the tin !
Which engine is featured in your picture, the paintwork looks incredible.

Andy
« Last Edit: February 01, 2016, 05:18:10 PM by Chipmaster »

Online Chipmaster

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Re: Retlas
« Reply #61 on: February 01, 2016, 04:56:21 PM »
Hi Jason, I will leave a gap between the hub and head of the gib key so I can use a fox wedge to remove it if necessary.

Andy

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Re: Retlas
« Reply #62 on: February 01, 2016, 05:02:19 PM »
Jason, I meant to ask you where you obtained the drip feed oiler in your picture showing the key being fitted. It looks like the size threaded 1/8" BSP that I used to be able to obtain from Graham Engineering (long gone)  in West Bromwich years ago. I think they used to cost 5 or 6 possibly 15 years ago.

Cheers
Andy

Offline Jasonb

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Re: Retlas
« Reply #63 on: February 01, 2016, 05:11:01 PM »
The one with the long keyway sticking out is the Galloway, The one with the key head (and small gap) is the Gade.

I have made all the oilers and greasers on the engines, let me know if you need a drawing.

I bought a set of small broaches 1/16, 3/32 & 1/8 and bushes which work well and can be pushed in with the drill press and also got a separate 3/16" one but have to borrow a press for that. As you say a lot easier than going back and forth on the lathe.

Offline Alyn Foundry

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Re: Retlas
« Reply #64 on: February 01, 2016, 05:18:39 PM »
Hi Andy.

No, not a typo, I have a 3/8 " broach. It's the largest in my set.

Have I read you correctly? If you have pushed the broach all the way through your flywheel hub then you will have a parallel keyway.

Kind regards, Graham.

Offline Alyn Foundry

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Re: Retlas
« Reply #65 on: February 01, 2016, 05:20:25 PM »
Hi Jason.

Thanks for the clarification, all clear and understood.

Kind regards, Graham.

Offline Alyn Foundry

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Re: Retlas
« Reply #66 on: February 01, 2016, 05:29:46 PM »
Jason, I meant to ask you where you obtained the drip feed oiler in your picture showing the key being fitted. It looks like the size threaded 1/8" BSP that I used to be able to obtain from Graham Engineering (long gone)  in West Bromwich years ago. I think they used to cost 5 or 6 possibly 15 years ago.

Cheers
Andy

Hi Andy.

That takes me back!!

We used to buy them at 100 a time from Graham engineering. I loved that place almost like a supermarket you just walked around putting stuff into your shopping basket. The prices were always reasonable and sometimes there were some rather unusual items, special tooling from bankrupt firms. I bought several long shank drill reamer combos for line boring.

Kind regards, Graham.

Offline Jasonb

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Re: Retlas
« Reply #67 on: February 01, 2016, 05:31:08 PM »
This is the picture I was looking for, seems I had not uploaded it to Photobucket :-[

1/8x 1/4 keysteel milled to appros 1/8 x 1/8 tapered on height with the vicegrips on the end.


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Re: Retlas
« Reply #68 on: February 01, 2016, 06:12:18 PM »
Hi Graham, the broach went right through the timing gear but I don't think it went right through the flywheel but if it turns out that I've got a parallel keyway I'll have to add a little taper using a file.
For a few years I worked in West Bromwich so Graham Engineering was extremely useful for me, their stock was terrific. That was a long way for you to travel.
Andy
« Last Edit: February 01, 2016, 10:06:00 PM by Chipmaster »

Offline Alyn Foundry

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Re: Retlas
« Reply #69 on: February 01, 2016, 06:34:01 PM »
Hi Graham, the broach went right through the timing gear but I don't think it went right through the flywheel but if it turns out that I've got a parallel keyway I'll have to add a little taper using a file.
For a few years I worked in West Bromwich so Graham Engineering was extreemly useful for me, their stock was terrific. That was a long way for you to travel.
Andy

Hi Andy.

Yes indeed, two hours but worth every minute. I always felt like a child in a sweet shop !!   :)

Re the oilers.. It would seem that well known British lathe manufacturer is selling the very same Taiwanese lubricators..... Hmmm there's quite a mark up too.

Kind regards, Graham.   

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Re: Retlas
« Reply #70 on: February 05, 2016, 02:37:15 PM »
I milled the 3/16" wide keyways in the crankshafts to match the keyways broached in flywheel and timing gear. It is difficult to see what's happening when using a small slot drill in my Clarkson milling chuck.
The gib head keys seemed to be a good fit but I won't hammer them home until the end of the build.

Andy

Offline Alyn Foundry

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Re: Retlas
« Reply #71 on: February 05, 2016, 02:53:46 PM »
Hi Andy.

I agree, it's quite difficult to see what's going on that's why I used to use the horizontal milling attachment on the Denbigh. Having two milling machines is wonderful if you have the space.

Kind regards, Graham.

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Re: Retlas
« Reply #72 on: February 05, 2016, 03:21:38 PM »
Hi Graham,

Even more difficult was the gib head key with a reverse taper.
I spent quite some time messing about trying to fit a brand new commercially manufactured key . When measured I found the key was tapered the wrong way - the height of the key decreased approaching the head !!  ::).

Anyway, the eccentrics and the eccentric strap retaining washers were straightforward machining operations on the lathe.

That brings my build log up to date, I'm going to start work on the valve chests but I'll have to think about making valve seat cutters first.

Andy
« Last Edit: January 21, 2018, 12:55:25 PM by Chipmaster »

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Re: Retlas
« Reply #73 on: February 08, 2016, 08:25:13 PM »
Spent yesterday assisting my friend exhibit at the Steam Toys In Action (STIA) event held at the Abbey Road Pumping Station Leicester http://www.abbeypumpingstation.org/  - an annual event that always attracts thousands of visitors.
Andy

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Re: Retlas
« Reply #74 on: February 08, 2016, 08:50:51 PM »
Did a bit more work to finish the half time gear and eccentrics today.
The hub of the 60 tooth half time gear has to be opened up to 1/2" and the projecting section of the hub removed to make way for one of the eccentrics This was done after centring the gear in a four jaw chuck the teeth were protected with pieces of copper. The 60 tooth gear and the two eccentrics are bored out to 1/2" and they're all intended to rotate together directly on a 1/2" steel axle. I would prefer to have a bronze bush running on the steel axle but haven't got bronze near that size at the moment so I made the temporary steel bush seen in the pictures below. It has a 3/8 bore and is running on a plain 3/8" diameter Whitworth bolt at the moment.
The inboard / inlet eccentric is fixed to the gearwheel with a 2 BA countersunk screw, the exhaust eccentric won't be fixed until the valve timing has been determined.

Andy