Author Topic: 1/3rd scale V10  (Read 293300 times)

Offline PStechPaul

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Re: 1/3rd scale V10
« Reply #45 on: May 16, 2014, 08:04:15 AM »
Every time I catch up on one of these threads I learn a little more about set-up and machining, and realize there is a lot more that I didn't know and still may need to learn. I'm inspired by what is shown to be possible (especially on manual machines), yet humbled by how crude my efforts have been in comparison. But I think that is the beauty of this hobby (although it seems almost sacreligious to call it that) - there is always more to learn and better skills to acquire (or aspire to).
 
Good luck with the rest of this build. Seems you are making impressive progress!

Offline keith5700

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Re: 1/3rd scale V10
« Reply #46 on: May 16, 2014, 09:03:08 PM »
Thanks for comments. Yes I'm stuck on the camshafts at the moment. I'll get some pics up soon.
I finally got round to hardening one yesterday (drill rod/silver steel) , but it bent about 2mm in the centre.
I tempered it in the oven and it bent a bit more.
So I tried to straighten it, but ended up snapping it.

I hardened the other three today but these didn't bend much, due to a better heating and quenching method, so I've started grinding them up today.
Been on them two weeks so far and still got to grind lobes and then make another complete shaft.
Cheers.

Offline keith5700

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Re: 1/3rd scale V10
« Reply #47 on: May 20, 2014, 12:57:05 PM »
some pics....
this is the depth gauge for setting the spark plug lengths. I went for a M6 x 0.5 thread, which looks extremely fine, but it means the ptfe liner can be a bit bigger diameter than in the old M6 x 1 threaded plugs.



This is a quick mock-up of the belt arrangement.



Cutting the timing pulley gears. This way turned out to be crap and I went over it again with a 2mm ball cutter after.



Vernier pulley details..





Milling out the camshaft blanks...


Grinding the cam lobes and centre bearing journals..







Offline Roger B

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Re: 1/3rd scale V10
« Reply #48 on: May 20, 2014, 02:05:10 PM »
Looking good  :praise2:  :praise2:

I'm trying to understand the last picture of the cam grinding. Is the master cam on the far left, driven by the timing belt from the chuck? Is there an indexing arrangement by the timing pulley? Is there some form of scaling linkage between the master cam and the grinding wheel?

Good luck in finishing all four  :ThumbsUp:  :ThumbsUp: I struggle with one single cylinder camshaft.
Best regards

Roger

Offline keith5700

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Re: 1/3rd scale V10
« Reply #49 on: May 20, 2014, 08:56:44 PM »
Roger, you are correct on all three observations. The indexing is on the left hand pulley in the pic.
I'll try and get a drawing up later. I made the jig for the v8 and then modded it for 1/3 scale for this, but when I looked at it I couldn't work out how I'd made it work the first time.
After a bit of head scratching I figured out how I'd done it, but a drawing will explain it better.
Cheers.

Offline Sacredbloodline

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Re: 1/3rd scale V10
« Reply #50 on: July 19, 2014, 05:41:41 AM »
::crickets chirping::

So, Keith, any progress in the past weeks? Just curious

Offline keith5700

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Re: 1/3rd scale V10
« Reply #51 on: July 21, 2014, 01:15:36 PM »
Yes, I've been plodding through all the valvegear for the past 6 weeks. I started to lose my way a bit, thinking that I should be doing something else with my life. I think it's because of the boredom of making 20 off of everything on the valvegear. I'm getting sidetracked very easily.
Pics to follow soon hopefully, cheers.

Offline Blackrat

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Re: 1/3rd scale V10
« Reply #52 on: July 29, 2014, 01:08:29 PM »
Awesome build !

PM'ed :-)

Offline keith5700

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Re: 1/3rd scale V10
« Reply #53 on: August 26, 2014, 01:03:48 PM »
Well I've finally got the valvegear sorted. It's taken ages, and I've got really bored with it.
Hopefully back onto some interesting stuff now.

Some random pics.....

4 x completed camshafts.


Camshafts with centre needle roller bearings.



top of valve with shim fitted. I gave up measuring the gaps in the end, and just went with looking for a line of light.
This gap is about 2 thou'.


Someone asked about the cam grinder setup earlier.
Here is the basic geometry, with 3:1 reduction from master cam.



Better pic of shims, and shim removal slot.



Collet for roughing out shims. they were hardened and then finished to size by hand.



These are valve blanks in pairs, before and after hardening..



grinding the valve stems after hardening..



I fancied covers over the cam pulleys so wasted far too much time knocking up a pair of these. Hopefully they'll be worth it..



Offline billmac

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Re: 1/3rd scale V10
« Reply #54 on: August 26, 2014, 03:42:43 PM »
Keith -

That is just superb. I'm so glad that you have persisted with this through a period of boredom. Please keep us posted on progress, which should be faster now that the big numbers of parts are done.




Offline Roger B

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Re: 1/3rd scale V10
« Reply #55 on: August 26, 2014, 07:15:02 PM »
Absolutely magnificent  :praise2:  :praise2: As I said two lobes is enough for me  ::) Still following along
Best regards

Roger

Offline agmachado

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Re: 1/3rd scale V10
« Reply #56 on: August 28, 2014, 02:21:24 AM »
No words... very cool!

Offline Allen Smithee

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Re: 1/3rd scale V10
« Reply #57 on: August 28, 2014, 10:07:13 AM »
I hope you don't mind a few quick "clueless newbe" questions?

Am I right in assuming that the basic cam blanks are turned, and then these are put in the mill to take the bulk of the unwanted material off the cam lobes (and presumably add any keyway features) before hardenning and then finally grinding the lobes to shape?

- How close to the final shape do you take it to the final shape in the mill (ie how much do you leave to grind off after hardenning)?
- What sort of speed do you rotate the cam whilst grinding?
- Do you grind to final form in one pass or do you let the follower lift off the master cam on multiple passes until it finally gets down to the required shape? If the latter what sort of contact pressure (weight) do you put on the grind-stone?

I know nothing of grinding, but several of my potential future projects will involve camshafts and I'm toying with the idea of making a dedicated cam-grinding machine/fixture using some redundant lathe parts but I need to know a lot more before deciding whether my idea would work!

TIA,

AS
Quidquid latine dictum sit altum sonatur

Offline keith5700

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Re: 1/3rd scale V10
« Reply #58 on: August 28, 2014, 01:03:48 PM »
Allen,
I started off in the mill and removed the excess in the lathe.
I did it this way as I could use the mill DRO to position the lobes accurately.
The lobes were then finally shaped in the mill with the dividing head, producing a series of flats.
I think I left about 20 thou' all round on the lobes for grinding, after hardening.
If your cams are short then you could get away with less. I had to leave enough on in case the shafts bent during hardening.
Cam rotated about 60rpm.
The follower is in contact with the master cam all the time. The whole thing is then gradually fed into the cam on the crosslide, until
you get down to the finished lobe size.
You will very quickly get a feel of what is the right feed rate.
You need to allow for coolant on the lobe all the time as it will get very hot very quickly.
you are only taking 1 or 2 tenths' per rev, if that. Any more and the grinding wheel will need trueing up all the time.
Cheers.
« Last Edit: August 28, 2014, 01:08:18 PM by keith5700 »

Offline Allen Smithee

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Re: 1/3rd scale V10
« Reply #59 on: August 28, 2014, 01:20:11 PM »
Brilliant! Many, many thanks Keith - that's exactly what I wanted to know.

AS
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