Paul,

I had a similar issue with a lawnmower that had a slightly different mounting arrangement. Do the old and new units look similar in layout of the laminations in the coil? If so the new unit needs to go as near as possible in the same orientation as the one you've taken off,to keep the spark timing right with some sort of adapter plate to facilitate screwing it down. The other important consideration is the air gap between the poles on the cdi and the magnet poles on the flywheel.My instructions were to use a piece of 0.005" perspex between them whilst tightening up. Runs like a Lotus 7 now!

Regards

Bob D

PS Howard beat me to the gap!

Edited By Robert Dodds on 13/05/2018 17:02:52

Mike,
Does the non drive shaft end have any sort of endcap covering the shaft end? Behind the end cap it is not unusual to find a circlip or similar device fitted on the shaft and hence retaining it in the motor end plate. You should also check where wire entry is because you could create other problems if you withdraw rotor and end plate as one and then find the wire connection plate is part of the end plate assembly.
A photo of your specific motor might help.
Regards Bob D

Peter,

Have a look at this Amazon product with a swivel ball joint. It may be the wrong scale for your application but the principle of a slot down the side of the ball cup to allow the "vice" (or your rod) to lean over should give you the flexibility you seek.

40231901 Aluminum Small Mini Table Clamp Hobby Jewlery Work Swivel 360 Vice

I got one out of Aldi some time back and it's useful.

Bob D

Stewart,

Two views of an angle clamp based on the classic toolmakers clamp. Made in 1940's and still useful today.
Bob D

Looks like they made cylinder headlamps too- unless someone has been doing a bit of phototricery on google.

Bob D

Things like that never happen on this forum!

Bob D

Brian,

Is this what you're after?. At £7 its not worth making and you can pick the size you want

**LINK**

Bob D

Hi,
Make your own backplate but I got one of these at 80mm dia and seems more than adequate
http://www.ebay.co.uk/itm/4-JAW-INDEPENDENT-LATHE-CHUCK-K72-80-TO-320MM-/27228

Regards Bob D

John,

As you can see they are becoming available again.
A truly magical adition to your toolbox.

Regards,

Bob D

A similar expression to Mike Poole's relation, my mother, a tailoress by trade, would say on fair weather days "There enough blue up thre to make a Dutchman a pair of breeches"

Bob D

Why not go for a legit version from Presto.
Presto councellor can be downloaded from

http://www.presto-tools.co.uk/Downloads
{bottom of the page}

Its got lots of data on drilling, tapping speeds and feeds for a variety of materials, milling rates and calculations as well as proper nomencclature of their cutting tools.
I got a pocket book many moons ago but i think its only available as a download currently

Bob D

Edited By Robert Dodds on 19/09/2017 21:54:31

As a North Midlander I recognise the "skunt" as a term for skewness but I also have come across those from Rose country who might refer to "Not wreck t' th ay"
In terms of scale, which is the greater, a gnats cock or a smidgin?
Can anyone elaborate on the difference between a Timper and a Spelcher?
I know that if it only a smidgeon out you can put it right with a Timper but big ones need a Spelcher to shift them
In the more refined Enginnering Shops the faulty part might be known as a cobble or clanger and finish up being "chucked on the shawd ruck" along with any other dingers.
Up and down the country there are many different dialects and workshops within each. They pick up words that associate with the particular industry or craft of the area and are meaningful there.
Its what makes the English language so colourful. Long may it last!

Bob D

Michael G,

Good to see you back.

I can't agree completely with your analogy to a pre tensioned car spring. The load direction of our tool bar is at right angles to the preload whereas the car spring restraint is coincidental with the load direction .
Treated as a cantilever, in the unloaded state the centre bar, in compression, induces an opposing tensile stress in the outer tube As a bending moment is introduced there is minimal effect on the inner compressed bar but the upper layer of the outer member will see increased tensile stress that can, depending on the preload level, take the upper skin towards the yield point of the material. The lower layer will see an equal decrease in stress level.
I would agree that no change in stiffness can result from this preloading.
It may be this unbalanced state of the material that experiences different resonance characteristics and alters the chatter pattern of the toolbar
I have some recollection that resonating characteristics of toolbars can be substantially modified by disrupting the vibrations in the bar with series of small holes drilled along the length of the bar after the fashion of tuning a flute or clarinet.
If they get it right I think the machine will even hum a tune for them

Bob D

My interpretation of the first photo is that there is a cross pin retaining the collar. It may be tapered but it seems to be quite heavily peened over on the visible side. You should carefully file or grind off that peened section from both ends of the pin before attempting to drift out the pin (from the thin end if its tapered). You should see the circles where the pin emerges from the collar and that indicates where to hit. As others say, with collar off withdraw the shaft by unscrewing to the front of the vice. Plus gas and a judicious tap on the shaft may be required to move the collar

Bob D

Taris,

From the photos it appears that when you move the reversing lever forward the carrier plate comes forward and is very close to the banjo arm that carries the 55 tooth gear. If they touch and prevent the detent pin on the reverser from engaging any torque on the drive will try to disengage the reverser gears. As Hopper says the 55 tooth is only an idler and could equally well be 60 or 65T and that would increase the clearance between carrier plate and banjo to allow the detent to lock in properly.
I've only the photos to go off so this may be irrelevant but I hope it helps.
By the way, What is the purpose of the flywheel in the left hand gearbox?

Bob D

Is nobody prepared to offer advice on the OP's primary problem? He scrapping parts because of bellmouthing!
My suggestion would be to acquire a good sharp 12 mm reamer to finish size the GM.
Bearing OD's are usually arranged to get the right fit with a nominal size bore but confirm this by checking your bearing OD.
The type of reamer, machine or hand, may depend on the through clearance you have beyond the 15mm bore for the reamer to run into.

Bob D

Anybody tried one of the hand held steam cleaners?.Various websites sell for under £25 and you get 3bar pressure off them Come with built in safety. valve. AND you will know where to find it if it goes missing.

Bob D

This article recently appeared in Design Solutions

http://www.bardenbearings.co.uk/Smaller_faster_hotter_optimisation_of_bearings_for_challenging_applications.html

Part of it mentions full complement bearings and the different types

Bob D

Roger,
Does your accuracy requirement include angular alignment of the dogs to the position of the gear teeth?

Bob D

Les,
Are you implying there may be a renewed demand for the motors. I can't see myself buying a car out of selling my three Suffolks though!!

Bob D