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Author Topic: calling all engineers  (Read 4646 times)

gwa84

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calling all engineers
« on: December 16, 2011, 10:28:24 pm »
hi peeps ime looking for a kind fellow mayhemer that has the skills and tools to manufature a simple collet fo an engine i have unfortunatly ime unable to fined enything of the shelf and dont have the tools to make it myself even tho i would luv to  :-))

sorry its not to scale

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Patrick Henry

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Re: calling all engineers
« Reply #1 on: December 16, 2011, 10:44:34 pm »
Try Mark at MMB.
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andyn

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Re: calling all engineers
« Reply #2 on: December 16, 2011, 10:44:52 pm »
Can make it in brass if you want?

Andy :-)
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MikeA

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Re: calling all engineers
« Reply #3 on: December 16, 2011, 10:55:12 pm »
yep go to mark all my custom made couplings and stuff come from MMB
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Colin Bishop

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Re: calling all engineers
« Reply #4 on: December 16, 2011, 11:06:15 pm »
Yes, MMB are recommended for bespoke components. very good to deal with.

Colin
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omra85

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Re: calling all engineers
« Reply #5 on: December 16, 2011, 11:15:27 pm »
Geoff,
If this is for an engine to flexishaft coupling DO NOT use grub screws! They will not stay tight as the wires in the flexi will deform.
Use a compression collet instead similar to this (HF191) http://www.prestwich.ndirect.co.uk/surfacedrive.htm
but with that crank thread you may have to get Mark (MMB) to make/adapt one for you.

Cheers
Danny
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gwa84

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Re: calling all engineers
« Reply #6 on: December 17, 2011, 01:35:43 am »
andy if you can make or adapt one with the recomended compresion fiting for 3/16th flex shaft that would be awsum if you can haw much do you rekon itle cost

cheers  :-))

thanks for the sigestions peeps and grub screws not working duly noted  :-)) :}
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Circlip

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Re: calling all engineers
« Reply #7 on: December 17, 2011, 09:19:34 am »
Just to clarify for newbies, what you've drawn GWA ain't a collet coupling, it's a sleeve coupling. Grubscrew locking on sleeve couplings is totally acceptable providing the bore has been machined to an interfearence fit on the shaft. The type required is so that you need to apply heat to the coupling to allow it to slide onto the shaft so it contracts and grips when cool. Many motors have fittings which are fixed on this way, cheaper ones rely on glue and due to the neccessity of clearence required for the adhesive also run eccentrically. Collets are closer but ideally should be bored to suit the shaft its to be fitted to.

  Regards   Ian.
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omra85

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Re: calling all engineers
« Reply #8 on: December 17, 2011, 11:49:41 am »
Geoff, are you SURE the shaft thread is 1/8" NPT?  What engine/motor is it for?
I've never come across a thread like that on a shaft.
http://en.wikipedia.org/wiki/National_pipe_thread

Circlip - you are absolutely correct IF the shaft is SOLID - but if it is to connect a "flexishaft" (a multi-strand cable) it should NOT be used with a sleeve coupling (grubscrewed or otherwise). ;-)

Cheers
Danny
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gwa84

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Re: calling all engineers
« Reply #9 on: December 17, 2011, 12:28:52 pm »
i thout it whas a weard thread but the die i have out of my kit that fits on the shaft and threads dawn nicly says on it 1/8npt27  thats all ive got to go on it a homlite engine

affter reading the wiki link its got me wondering just of to check things over agean  :-))
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Circlip

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Re: calling all engineers
« Reply #10 on: December 17, 2011, 12:56:46 pm »
Quite right Danny, but you've added another facet to the final use of the "Coupling" that wasn't mentioned in the O/P

  String, long and how spring to mind again.

   Is it to be used on a bait boat with a three mile range????????  {-)

   Regards  Ian.
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You might not like what I say, but that doesn't mean I'm wrong.
 
What I said is not what you  think you heard.

gwa84

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Re: calling all engineers
« Reply #11 on: December 17, 2011, 12:59:11 pm »
took it to a frend across the road ho has a better tap and die set he has mesured it and came out with m10x1.25  wich is a snug but not to tight fit  :-))
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omra85

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Re: calling all engineers
« Reply #12 on: December 17, 2011, 04:12:11 pm »
Ah, M10 sounds much more likely  :-))
So the next question is - if you are connecting it to a Homelite (which I assume is a petrol engine about 23/26cc) there will be quite a bit of power.
Is there any particular reason for using a 3/16" flexi, rather than the more usual (and stronger) 1/4" size?
Not saying it won't work fine, but 3/16" is the size I use on my 3.5cc, and most boats over 7.5cc have 1/4" flexis.

Cheers
Danny
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gwa84

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Re: calling all engineers
« Reply #13 on: December 17, 2011, 05:41:44 pm »
its whats fitted to boat been runing like that for afew yeers naw untill the cupling broke last year
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