Rob Roy

**Dalboy** · 23rd April 2022, 06:20 AM

Well the wheels are complete with all the webs cleaned out and the crankpin holes drilled and reamed. I was coming out of the workshop with black hands and face where I wiped it without thinking.

I made a simple jig to aid in drilling the crankpin holes which I did on the milling machine two drill bits and the reamer to get them to a size needed. Now to make the crankpins three different designs and sizes as well as axles. Even then I will not be able to fix them together as I also need to make other parts to fit the axles before the wheels can be pressed together and quartered. That will required another jig to get them correct

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**Keith_1** · 23rd April 2022, 09:33 AM

Hi Derek,

It's looking great mate. Top Work.

Regards

Keith

**Dalboy** · 25th April 2022, 06:36 AM

More done on the wheels started the crank pins by turning the end that is pressed into the wheel and cutting each one to just over the length needed. I managed to complete two and fit them. The photos show the two complete one with a pin showing the machined end and the last a photo of the four still to complete. I had a total of three failures where I machine off 2 thou too much so on the rest I made them 1 thou over and used wet and dry for the very last bit. The two I have completed are a nice press fit

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**Keith_1** · 25th April 2022, 10:26 AM

Good stuff Derek

Regards

Keith

**Dalboy** · 26th April 2022, 03:35 AM

Finished the crank pins and fitted them. Still need to make the axles but will make some eccentrics which will need to go onto one of the axles before they are fitted to the wheels.

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**crowie** · 27th April 2022, 06:06 PM

So much precise engineering in this project Derek....

Lots of patience required, Cheers Peter

**Dalboy** · 27th April 2022, 08:06 PM

Thank you Peter. I am enjoying the building and learning so much in the process. Yes made a few mistakes errors most of which are learning the machines.

**Dalboy** · 11th May 2022, 11:08 PM

Been a little busy lately so was not able to do much on the loco. Now the weekend is over and all my woodturning put away after a great weekend at a rally(No photos)

I have however managed to make the parts for the motion plate and bracket as I am waiting for some more steel to do the axles.
Anyway I made these over a couple of days while trying to catch up in the garden.

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Still waiting for some steel bar for the axles as I ordered them over a weekend so I got the eccentrics turned and the offcentre holes drilled and reamed still need to dril and tap for the grub screw to lock them on the axle I will use the same jig that I used to do the hole(I will take a photo of it tomorrow as I forgot to do so when I took the photo of the eccentrics).

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test fit on a piece of BMS bar

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**Dalboy** · 12th May 2022, 05:52 AM

As promised todays work and an overview of the jig use.

This is the set up for doing the off centre hole and drilling and tapping the thread for the grub screw may not be how many would do it but it seemed to work for me.

The jig with a turned eccentric this was after I had drilled and reamed them just to show one in situ.

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Again just set up for the photo as it would sit on parallels and be lined up with the end of the vice for repeatability. Note the slit so it could grip the eccentric from moving during this operation

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second operation I had marked the eccentric so that I could line it up with the scribed mark on the little jig. Drilled and tapped

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Needed to finish the tapping in a vice

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Cleaned the inside of the bore where the thread came through using a small circular diamond burr to clean up the burrs

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**Peter White** · 12th May 2022, 06:34 AM

Great work very exacting am sure will look great when all done.

**Dalboy** · 12th May 2022, 09:27 PM

Originally Posted by Peter White

Great work very exacting am sure will look great when all done.

Thank you Peter. I hope it looks and runs good also when it is finished but still a very long way to go

**Keith_1** · 16th May 2022, 10:02 AM

Your machining and fitting work is first class

Top Marks Derek

Regards

Keith

**Dalboy** · 17th May 2022, 07:01 AM

Spent today making up a jig/fixture to quarter the wheels I am trying to keep it simple. I cut two pieces of ali plate 10mm thick and squared it all around to 3.750" found the centre and drilled and tapped a hole through both at the same time this was tapped to 5mm as that is what I had in a screw for the purpose I needed it for. From that centre I marked and drilled the offset equal to the offset of the crank pins followed by reaming it to 1/4" the same as the pins.
Took a few photos to give an idea how the set up will work once complete.
Because I squared each plate by turning one 90deg will give the correct angle for quartering. The two screw threads will have a point machined to go into the centre of the axles by slackening them off a fraction at a time while pressing the assembly together should keep everything in line I will be doing this on a surface plate to keep the jig from twisting.

After taking the pictures I have decided that a little modification to the jig is needed will try tomorrow

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**Keith_1** · 17th May 2022, 10:09 AM

Top work Derek.

Although time consuming making Jigs and Fixtures initially - it's definitely worth it in the long run.

Loving your build.

Regards

Keith

**Dalboy** · 20th May 2022, 04:46 AM

Originally Posted by Keith_1

Top work Derek.

Although time consuming making Jigs and Fixtures initially - it's definitely worth it in the long run.

Loving your build.

Regards

Keith

Still making bits and pieces need to make some t nuts for the rotary table as will need that soon as well

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