Author Topic: Two Cylinder Engine  (Read 18641 times)

Offline Roger B

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Re: Two Cylinder Engine
« Reply #180 on: June 20, 2019, 08:04:05 PM »
Another problem  :( I case hardened the camshaft together with a couple of head gasket punches. Whilst I was polishing the camshaft with emery cloth in the lathe it snapped off  :facepalm:

The broken face had the same even grey finish as first time so my piece of free cutting MS was obviously not what I thought it was  :toilet_claw:

I took a selection of pieces of 10 - 12mm diameter steel and parted off 1mm thick discs. The first two I heated to dull red and then quenched. They were clamped to half diameter in the vice and bent. Both failed with brittle fractures. The next sample machined nicely and I tried it first without heat treatment. It bent but cracked, after heat treatment the result was similar. The last sample was not so nice to machine but bent without cracking.

I obviously need to keep my material stock under better control  :headscratch: and learn how to analyse the grinding sparks  :thinking:
Best regards

Roger

Offline Ye-Ole Steam Dude

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Re: Two Cylinder Engine
« Reply #181 on: June 20, 2019, 08:31:22 PM »
Hello Roger,

Sure hate to see that happen to you, it can be frustrating when you get faulty material or mislabeled material.

Have a great day,
Thomas

Offline Roger B

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Re: Two Cylinder Engine
« Reply #182 on: June 24, 2019, 06:47:35 PM »
Thank you Thomas  :ThumbsUp:

Better luck this time  :) I selected a piece of free cutting MS which had a noticeably better finish after milling the cams, very little polishing was required.  After case hardening a little finger pressure was required to reduce the runout to less than 0.05mm and it assembled and turned freely  :whoohoo:
Now I can set the timing and make the pushrods  :)
Best regards

Roger

Offline Admiral_dk

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Re: Two Cylinder Engine
« Reply #183 on: June 24, 2019, 09:51:45 PM »
Nice to see that you have progress again  :cheers:  all the more important as this engine hass to earn it's keep.

That said - I truly know the feeling ; Yeah I finally moved forward - only to realize that this has to be followed by two (or more) steps backward  :???:

Best wishes

Per

Offline fumopuc

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Re: Two Cylinder Engine
« Reply #184 on: June 26, 2019, 09:32:12 PM »
Hi Roger, finally a perfect result. Congratulations. I have to learn these cam lobes milling to.
Kind Regards
Achim