Postman Cometh Part 2

[JasonBModerator @jasonb]

Sounds like you need to get yourself an edge finder or a centre finder/sticky pin to pick up the joint

J

PS have you sorted out your DRO problem yet?

[Nick_GParticipant @nick_g]

Posted by JasonB on 01/09/2015 19:23:20:

Sounds like you need to get yourself an edge finder or a centre finder/sticky pin to pick up the joint

J

 

PS have you sorted out your DRO problem yet?

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My thoughts are that if I use the 12mm PGB that I could also check the vertical alignment of both bearings is good. I don't think my edge finders are long enough to do that with the lower mounted one. Suppose I could use the laser one.

Yes, DRO problem sorted. That was down to the idiot that installed it not doing a finished job. – Now I wonder who that was. i.e. the sensor to magnetic scale was not tightened. Ooooops.!

Nick

Edited By Nick_G on 01/09/2015 19:34:24

[JasonBModerator @jasonb]

If you don't have a decent angle plate to mount the casting to then thats probably your best bet of getting the two bearings vertical.

J

[Gas_mantle.Participant @gas_mantle]

Nice work Nick, I'll look forward to following this thread

Peter.

[Nick_GParticipant @nick_g]

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Thank you Peter.

Work on the bearings has had to take a break for a couple of days. This is due to me being a numptie and not being in possession of a 4BA tap to hold the caps down. So I hope Messers Chronos dispatch the ordered one pronto.

Nick

[mechman48Participant @mechman48]

M3.5 / M4 would've been the nearest equivalent taps if you were stuck… ?

George.

[JasonBModerator @jasonb]

Probably best to stick with 4BA then you can use the supplied nuts & studs, Nice chart, where have I seen that before

[mechman48Participant @mechman48]

Hmmm let me think … … gadzooks sir twer it not yours…

[Nick_GParticipant @nick_g]

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Cheers mechman,

But as Jason says I have the studs and I have ordered the HSS taps now.

I also really need to replace the existing BA taps I have with HSS ones also. I was very lucky I did not snap the cheep carbon steel ones I bought when building the James Coombes off in castings a couple of times.

Nick

[Nick_GParticipant @nick_g]

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I have been waiting for some tools to be delivered. (still not arrived today )

So I spent a bit of time over the weekend making a few tools that I will need. I need at some point to drill and face off the standard. This is quite close to other parts of the casting so I would not be able to do it with standard bits of kit. I therefore turned some scrap drilled and reamed the ends to accept such. These were locktited in as they will not be required to be a long lasting service item.

The milling bit and drill were held in the tailstock to ensure they went in reasonably straight.

This is what they are needed for. :-

Also made some T nuts to take some M8 fixings that will be required later. (the ones I already have take M10)

The fly wheel is 5in dia (or hopefully will be ) In order to mount it on the faceplate I would have to drill extra tapped holes into the hub of the D1-3 section. It's not the best of quality faceplates anyway and I am aware that before too long and many projects it would end up looking like the backstop wall after a Mafia firing squad had been active. So on the recommendation of another member I purchased a 20mm thick piece of aluminium. This I will drill and tap onto the plate. (and hopefully stiffen it up a bit) I can then drill and tap fixing holes when ever and where ever I want in the best position for many years to come. Well I hope for many years anyway the price of the damn stuff.

Nick

[JasonBModerator @jasonb]

You may find that milling cutter gets a bit lively when you try to use it that far out of the chuck, what you really need to make is a reverse spot facer, easily filed up from a bit of Silver steel, hardened and then clamped onto your drill bit.

Can you not use the 4-jaw to hold the flywheel by the inside of the rim? You can usually fit a six spoke in OK

[Nick_GParticipant @nick_g]

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Hi Jason,

That is an inovative way of doing it by reversing the casting. I would never have thought of that. I have though done it before I posted that image and your response.

I was mindful of possible chatter but I just had to spot face not cut into a fillet of the casting as you have done. It went OK, but if I had material at an angle to remove I would I think have had problems. Your method is going into filing cabinet in my bonce for future use though.

I did consider the 4 jaw for the fly wheel as you suggest, but I think I will be more confident with the faceplate method.

Thanks, Nick

[JasonBModerator @jasonb]

Same cutter can be used the right way round fixed to an extended drill or bit of rod so you have a spigot that locates in the hole much like an off the shelf counterbore.

I'd also slip a bit of MDF or ply between your ali plate and the flywheel, that way you can machine right across the rim without scoring that nice shiny new plate

Edited By JasonB on 08/09/2015 07:47:41

[Nick_GParticipant @nick_g]

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Hello again folks.

It's been a while since I did any work on the No.4. Hopefully I can now get back into the swing of it after my little interlude of making some parts for my mates motorbike turbo conversion. Work has also got in the way of things amongst other distractions.

I don't know how others drop straight back into a project. But I find it takes me a few sessions to remember where I was and my plan of attack.

Anyway. Decided to finish the main bearings. So they were mounted onto the milling table and drilled out in stages.

I did ream to final size but forgot to photograph.

Then onto machining the flywheel. I decided to use the faceplate method.

I drilled and tapped some holes to fix the flywheel and mounted it with some ali spacers behind.

There was an inconsiderate blow hole that reared it's ugly head while facing one of the sides. So I had to machine a bit more off than I would have liked. There is still a little bit visible though Grrrrrrr.! But I suppose I can live with that.

Resharpened the tool for the final cuts and while it was in the lathe gave it a polish that if had been witnesses by the safety Nazi's would have caused outrage.

Flipped it over and skimmed and polished the other side face.

In the morning I will decide what part I shall puzzle with next.

Cheerio, Nick

[Nick_GParticipant @nick_g]

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Con rod time I think.

I have made a sort of split collet out of aluminium so that I can 'hopefully' hold the rod for the rest of the machining jobs. Any other ways of doing such would of course be welcome.

Nick

[Nick_GParticipant @nick_g]

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The bearing was sliced with a slitting saw and then faced each side.

It was then fastened back together with solder and machined into thus :-

Another blast of heat to separate the halves again.

Which just leaves a tad of final dressing and a polish.

Nick

[Nick_GParticipant @nick_g]

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Onto the crankshaft.

This is the supplied casting.

However.! I propose to alter the design slightly as I hope for this engine to actually do some work.

1) Beef the diameter up slightly.

2) Add additional extra outboard bearing making 3 in total on a pedistal (similar in style to the James Coombes and Victoria but slightly bigger) as I feel this will reduce 'whip' on the shaft and provide extra lateral support upon it at the point of the pulley.

3) Increase the length of the shaft to facilitate the extra bearing.

4) Make the webb of the crankshaft so that it has counterweights for hopefully smoother running. (and look 'prettier' . )

Avante' :-

Nick

 

Edited By Nick_G on 08/11/2015 12:38:09

[Nick_GParticipant @nick_g]

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Next onto the parts that will make the crank web.

I turned some bar down to 2 1/4" and faced it off. I would really have liked to have used the flange jaws in the chuck. But I would not have been able to then get the parting tool in.

Formed a recess and drilled and reamed the center out.

Parted off a bit on the fat size to allow me to reverse in the chuck and make an accurate width.

Obviously 2 need to be made.

I can now split the size by 1/2 ( plus a smidgin ) to give me the final width for each side of the web.

I now need a hole for the big end and to carve out chunks from each side to form the counterweight. The look of each I am yet to decide upon. Think it may be best to temp bond the 2 together when making the holes for the big end.??

Also undecided if to bond and pin the sections with 638 or to silver solder. ??

Nick

Edited By Nick_G on 15/11/2015 21:51:05

[mal webberParticipant @malwebber91786]

Hi Nick nice work, your builds are very interesting to follow thanks

Mal.

[JasonBModerator @jasonb]

Posted by Nick_G on 15/11/2015 21:49:48:

. Think it may be best to temp bond the 2 together when making the holes for the big end.??

Ideally the hole could have been done while you had one lump of metal, If your DRO is now working and you can accurately locate centre then no real reason to do them as one, if you are not sure of being able to set them up for equal offset then stick together. Solder construction for me.

Looking good, smashing, super work, etc now you should not be feeling depressed.

[Nick_GParticipant @nick_g]

Posted by JasonB on 16/11/2015 07:29:03:

Looking good, smashing, super work, etc now you should not be feeling depressed.

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lol . So when do you want Belmarsh 'Belinda' to call.

Nick

[Nick_GParticipant @nick_g]

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Work on the webs continues.

Deciding which back rake angle to go for. – On the advice of Jason I went for 30 degrees.

Getting there now.

Then a blip of heat to break the loctite bond.

So it will soon be time for me to have a go at silver soldering for the first time. If it goes pear shaped at least I can sniff the tipex.

Nick

[JasonBModerator @jasonb]

What flux are you using Nick? the HT5 or Tenacity No5 is better for big lumps as it stays lively for longer.

J

 

PS did you have a problem drilling out those holes?

Edited By JasonB on 21/11/2015 17:12:09

[Nick_GParticipant @nick_g]

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Morning Jason.

Thanks for the advice. I shall order some Tenacity No.5 as you suggest. With this being the first silver soldering I have done I suppose I will not have the 'feel' of it totally. So a flux that stays in the zone longer will be of a good help.

The holes.? – I presume you mean because they do not look smooth in the bore.? They are. It's just that they have crud in them from dressing the rest of the webs.

I have had a mail from another member asking how I got rid of the tool machining marks. – I used a fine file, emery paper and a Dremil with the following abrasive in. :- **LINK**

Nick

[JasonBModerator @jasonb]

Posted by Nick_G on 22/11/2015 09:09:02:

The holes.? – I presume you mean because they do not look smooth in the bore.? They are. It's just that they have crud in them from dressing the rest of the webs.

No, I saw a photo you uploaded

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