Author Topic: Another member...  (Read 413 times)

Offline cparsons

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Another member...
« on: October 15, 2019, 04:54:44 PM »
Hello, Chris Parsons from the SW of the UK

Been involved in ME for a while and have (finally) started to look at building a 'Paddleducks' engine from the fantastic series of posts from 'BogStandard'

I have the 'book' and plans and have been going through them and have a couple of comments/questions - the plan of the components
looks to have an error - the stand off flange for the steam control is showing a 6mm hole - should be 4mm?

I am also struggling to find suitable bolts to join the eccentric straps together - 2.5mm is specified (around 14mm long) but the strap is 4mm wide - and all the bolts I have found have heads larger than this (4.5mm is the smallest) and will foul the 4mm channel in the eccentric??) I could use 2mm bolts and alter the eccentric strap holes/tapping but wonder what others have done?

Buying some supplies at the MMEE in Leamington Spa this weekend hopefully (iron for the block and some brass sheet for the support plates)

Regards

Chris Parsons
Newton Abbot and District
Model Engineering Society


Online Kim

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Re: Another member...
« Reply #1 on: October 15, 2019, 06:06:32 PM »
Hi Chris,
Welcome to MEM!

I haven't built BogStandard's Paddleduck engine, but I'm sure there are people around here who can help you regardless.  I did look at that engine when I first started this hobby, but ended up not making it.  So I am familiar with what you're looking at.  Seems like a great little project to me!

Kim

Online crueby

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Re: Another member...
« Reply #2 on: October 15, 2019, 06:13:52 PM »
Welcome Chris!

The width of the heads on the bolts for the eccentric straps is a common issue - many times I have filed the heads down a little to make them flush with the width of the straps, if I could not find small-pattern nuts/bolts.

Online Roger B

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Re: Another member...
« Reply #3 on: October 15, 2019, 08:00:38 PM »
Welcome to the Forum  :ThumbsUp:  :ThumbsUp:

I don't know the engine in question but here on the mainland we can get metric model engineering fasteners with smaller spanner sizes than standard. I am sure others on here can suggest suppliers in the UK.
Best regards

Roger

Offline Jasonb

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Re: Another member...
« Reply #4 on: October 15, 2019, 08:50:51 PM »
This seems to show M2 being used in fig 102.

http://www.machinistblog.com/downloads/paddleduck/04_building_a_model_steam_engine_from_scratch_chapter_4_567_418.pdf

While at the show visit polly engineering who do small hex metric fixings, there M2.5 have 3.5mm AF hex heads.

looking at the standoff Fig 110 the only 6mm I can see is the large diameter at the end of the shaft

« Last Edit: October 15, 2019, 08:59:31 PM by Jasonb »

Online b.lindsey

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Re: Another member...
« Reply #5 on: October 15, 2019, 10:37:53 PM »
Hello and welcome to the forum Chris.

Bill

Offline cparsons

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Re: Another member...
« Reply #6 on: October 16, 2019, 09:47:16 AM »
This seems to show M2 being used in fig 102.

http://www.machinistblog.com/downloads/paddleduck/04_building_a_model_steam_engine_from_scratch_chapter_4_567_418.pdf

While at the show visit polly engineering who do small hex metric fixings, there M2.5 have 3.5mm AF hex heads.

looking at the standoff Fig 110 the only 6mm I can see is the large diameter at the end of the shaft

Yes, looking again you are quite right - don't know where I got the 2.5mm from! 2mm cap screws have 3.8mm heads by the looks of it so there is no problem, thanks

The 6mm diameter I referred to was incorrectly shown on the DXF/DWG plans - 'Component sheet 1'? It is fairly obvious as it touches the mounting holes

Regards

Chris