Elmers #25, my first engine project

[bogstandard]

Forget the numptyness, as long as you got the job done, that is all that matters.

Coming along well there, and it looks like you are enjoying yourself to boot.


Bogs

[Darren]

You are no longer allowed to call yourself a newbie, ok.....

Give you six months and you'll be showing everyone how to do the hard bits 

[spuddevans]

it looks like you are enjoying yourself to boot.

You got that right, I'm loving it. This is soo addictive. ( surely this must be illegal, it has to be  ) I think I've been struck down with 

Does anyone know of a treatment? ( I have heard that 3-in-1 oil applied twice daily behind the left ear does help )

You are no longer allowed to call yourself a newbie, ok.....

Give you six months and you'll be showing everyone how to do the hard bits 

Thanks for that Darren, I cant imagine that I'll be showing anyone how to do the hard bits, I can see myself showing folks how to do the simple things... in the most complicated, hardest, most frustrating way 


Tim

[sbwhart]

Hi Tim well done you got the job well sorted.

 

As promised pics of my boring bars they may help with future jobs.







Stew

[spuddevans]

As promised pics of my boring bars they may help with future jobs.

Thanks Stew, seeing those makes it a bit easier to know what I can crudely hack out for future uses 

The set of boring bars in the wooden block above are identical to the set that was lurking in the corner of my workbench, totally forgotten about until Bogs reminded me I could use such on the lathe. 



Tim

[Bernd]

Tim,

I think you've been telling us porkies. No newbie can single point a small thread like that and get away with it the first time around. 

I think your either not a newbie or you've got natrual talent. I think the later may be it.

Looks like you got a good finish with that boring bar. Keep it up and you'll be running with the best of them.

Bernd

[spuddevans]

Tim,

I think you've been telling us porkies. No newbie can single point a small thread like that and get away with it the first time around. 

Well I did show you just one pic of my first project, ( I gotta take some more pics of them ) the 6 Led lights? They all are made up of a 2 piece construction that are threaded together. That is where I learnt a lot about single point threading, also where I made quite a few mistakes too. ( there's a few verry loose threads on a couple )


But the threading on this was a lot easier as I was just copying a M3 screw and I had a M3 nut on hand to be able to stop and check if I was close. I just started out by measuring the diameter of the M3 scerw threaded portion, turning the brass pin down to match, changed to the threading bit, engaged the half-nuts and threaded it 0.05mm at a pass until the nut would screw on to the brass pivot pin.

It's a bit easier when you have something to copy.


Tim

[spuddevans]

I managed to sneak a couple more hours in the playroom workshop this afternoon.

I started off by         off a little lump of brass for the piston and chucking in the 4jaw, turned down half to diameter.


I then chucked it the other way round in the ER32 collet but made the error of not tightening it enough and it came loose just as I was parting it off to length 

So I added to my collection of spare "smaller than I wanted" pieces and hacked off another lump of brass, chucked it and turned it down as before. This time I also drilled and tapped M3


I find this to be a good method of tapping on the lathe, to explain; The drill chuck is not jammed in the MT of the tailstock, it has some grip but is free to turn with light pressure. Also the tailstock is also free to move on the ways, and the tap in the chuck is also loose enough to turn if the tap jams in the work. I then run the lathe at a very low speed.



So that's all I got done today, just 2 pistons made, 1 junked and one that fits ok. If I put a M3 screw in the piston and slide it into the cylinder and turn it upside down the piston gently slides down and stops at the entrance of the cylinder, with out the screw it just falls out. I dont know if it's too loose, if I pull the piston out rapidly I get a satisfying "pop".

How do you tell if the piston is too loose or not?

Things I've learnt today;

I learnt that my ER32 chuck has a runout of 0.02mm, is that bad?

Always start off with a piece of metal that is longer than you need as it makes life easier.

I also tried making a con-rod out of 303 stainless, it didnt go quite as planned but I learnt that it really helps to use sharp carbide tooling and that it doesn't like my Hss threading tool.(prob was a bit dull, I must resharpen it) I'll try again the next time with some brass as per the plans.

Also learnt to think a few steps ahead to see what I can do while workpiece is still chucked and true before taking the piece out and then spending 15mins truing it up with the trusty dial indicator.

And finally, always remember to check that whatever chucking device is used is properly tightened up.



Tim

[Darren]

Excellent work again there Tim, 

I like to turn SS fast, very fast and with fast feed, but only with tungsten tipped cutters.

If you are using HSS tooling then keep the speed down low or you'll just burn the tip opp the cutting tool.

Nice clear pictures btw, 

[Brass_Machine]

... I dont know if it's too loose, if I pull the piston out rapidly I get a satisfying "pop".

How do you tell if the piston is too loose or not?

[/quote]

That sounds good to me. If it was too loose, you wouldn't get the "pop"

Eric

[spuddevans]

Thanks Darren, I was threading, or should I say, trying to thread at a very slow speed, but I think combined with the slightly blunt Hss toolbit was the fact the 303 was only 2.9mm diameter and was deflecting away and above the cutter, and that was with only 8mm of the 303 protruding from the chuck.

I bring my Dslr out to the workshop and hide it under some clean rags and bring it out when I remember. My other hobby is photography so it's nice to combine both hobbies.


Thanks Eric, I was wondering whether when I finished the build and 1st applied the air I would only get a hissssss  and no movement. Hopefully that won't happen.


Tim

[CrewCab]

I learnt that my ER32 chuck has a runout of 0.02mm, is that bad?

If my maths is correct  that's about three quarters of a thou ................. so not bad at all methinks 

Engine looks to be coming along fine btw 

CC

[sbwhart]

Tim

Ha the good old pop test, thats a good sign   I'm sure it will be fine.

The bad guy with these little engines is Mr Friction, you can have things too tight.

Nice work

Stew

[Bernd]

Ok Tim, we got the satisfying "pop" so that means a pretty darn good fit. 

Now, I went back and looked at your cylinder with the pivot in it. Are you going to forget to drill the entery hole for the air into the cylinder?  Just wondering. 

Nice job so far by the way. It took me several tries to get the piston right to make a good sounding "POP".

Bernd

[Divided he ad]

Nice looking parts collection you got going there Tim 


As Darren said "nice clear pictures" I know you said about the DSLR, But have you got very good lighting in there too? They are very bright and unshadowed!


I like this thread..... Reminds me a bit of my first engine thread way back when (all of a year ago !!  ) it feels good to make these little things and have them run for the first time...... You wait, it's a great feeling   




Ralph.

[SPiN Racing]

Coming along nicely!!

I cuss a lot and shake my head complaining about Brass VS Stainless steel when doing things on my stuff. The majority of the material I have is either Stainless or Tool Steel. Either of which is a bear if you dont do things right. This I know because if you look back through my posts you see me asking questions like.. Why doesnt this cut smoothly, or why is this so tough?

I can actually work with stainless fairly ok now.. Not good.. but OK. But as you mentioned.. a sharp tool is the secret.

Another secret I discovered... I use the generic re-grindable Carbide tipped tools for aluminum and brass and normal steels.
I invested in a set of indexable carbite tool bits from ebay for the lathe when turning stainless, and or tool steel. Makes a HUGE difference. The stuff cuts like butter with a good sharp indexed tool. Granted... if you are spinning a smaller diameter piece of metal it can be difficult. I just take a lot smaller cut to reduce deflection, and increase accuracy of my cuts. Takes longer but less cleanup after the fact.

I seriously have a hankering to make a engine.

(Must finish tool holders.. all 18 of them)

[spuddevans]

Now, I went back and looked at your cylinder with the pivot in it. Are you going to forget to drill the entery hole for the air into the cylinder?  Just wondering. 

Well spotted!! Actually I deliberately have not drilled it yet. I figure on assembling the whole thing together, positioning the crank so that the cylinder is in the right position for the exhaust hole in the frame to line up with where the inlet hole is meant to be on the cylinder, and then spotting through to accurately mark up the postion. Does that make any sense outside of my head?

As Darren said "nice clear pictures" I know you said about the DSLR, But have you got very good lighting in there too? They are very bright and unshadowed!

Thanks Ralph, Yea I have a flash(canon 580) mounted on my camera(canon 400d), but rather that aiming the flash dead ahead I aim it straight at the (grubby)white ceiling to bounce the flash. It provides a nice even, mostly shadowless light. My regular workshop lighting is 2 flurescents, 1 5-foot and 1 4-foot.

Another secret I discovered... I use the generic re-grindable Carbide tipped tools for aluminum and brass and normal steels.
I invested in a set of indexable carbite tool bits from ebay for the lathe when turning stainless, and or tool steel. Makes a HUGE difference. The stuff cuts like butter with a good sharp indexed tool. Granted... if you are spinning a smaller diameter piece of metal it can be difficult. I just take a lot smaller cut to reduce deflection, and increase accuracy of my cuts. Takes longer but less cleanup after the fact.

I have a couple of indexable carbide tools and found like you said that it cuts better on stainless, my trouble was with single point threading such a small diameter. I think I'll resharpen my Hss threading tool, take lighter cuts, and if needed use a steady rest to try and stop the workpiece riding up onto the tool. Either that or try using a M3 die (which will hopefully arrive in the post today  )


Tim

[Darren]

That's one expensive flash unit you are using.....

No wonder you keep it all under a rag till needed.

I use a 350D and have to say I'm very happy with it, but I'll stick to the inbuilt flash for now cos I'm a skinflint....

[Bernd]

Now, I went back and looked at your cylinder with the pivot in it. Are you going to forget to drill the entery hole for the air into the cylinder?  Just wondering. 

Well spotted!! Actually I deliberately have not drilled it yet. I figure on assembling the whole       gether, positioning the crank so that the cylinder is in the right position for the exhaust hole in the frame to line up with where the inlet hole is meant to be on the cylinder, and then spotting through to accurately mark up the postion. Does that make any sense outside of my head?

Tim

Never thought of doing it that way. Sure would put the hole in a more precise location.

See even a newbie can teach a guy that built two of these new tricks. 

Bernd

[spuddevans]

Today's update.

I started out by sharpening my threading tool and spending 15-20 mins trying to single point 3mm 303 stainless for the con-rod. Deciding that beating my head against that particular spike was not fruitful , I moved on to machining a new con-rod out of brass. This was much easier.



Then I extended a bit more out of the chuck and turned that down.



Once turned to size it was over onto the mill, I mounted it into the spin indexer thingy, supported the free end with a 3-2-1 block and a little stepped thingy and drilled out the hole for the crank, 2.4mm if I recall correctly.



After a little cleaning up and filing the edges round I have a piston with con-rod 



After that I had a little time so I made a start on the crankshaft assembly, specifically on the crank disc which I made out of some unidentified steel, turned some down to 17.5mm, hacksawed it off and remounted it in the ER32 chuck, faced it off and then drilled it 4mm.



So next will be the offset hole, and then the actual shafts.


Thats all for now, gotta run out to the post office to pick up some goodies.


Tim

[CrewCab]

Nice use of the various "thingie's"  ............. perhaps we should have an appropriate ..... thingy ....... smiley

From the write up's it seems you are enjoying this engineering lark more and more as each day goes by .......... nice write up and nice work Tim.

I started out by sharpening my threading tool and spending 15-20 mins trying to single point 3mm 303 stainless for the con-rod. Deciding that beating my head against that particular spike was not fruitful

I've gotta say, after a brief venture into the dark art of "Single Point Threading" .......... for the few sizes I tend to use I find it much quicker and easier to use a tailstock die holder 






However, I wait with trepidation to learn the error of my ways 

Dave ............. aka ..........   CC

[bogstandard]

I can smell a runner from here.

You and your self appointed newbie status has surely taken a beating this time, you are doing most of this stuff like an old hand.

Just get your materials together and knock one of mine out.


Bogs

[spuddevans]

Just get your materials together and knock one of mine out.

I have already got about half the materials  I will have a couple of inbetween projects to do though, I need to make a belt drive for my mill, and then a flycutter, and a few more little helpful bits.

But I'm getting ahead of myself, gotta finish this one off first. 

From the write up's it seems you are enjoying this engineering lark more and more as each day goes by .......... nice write up and nice work Tim.

I am, I really am     

I've gotta say, after a brief venture into the dark art of "Single Point Threading" .......... for the few sizes I tend to use I find it much quicker and easier to use a tailstock die holder 

Actually I find single point threading quite enjoyable, and surprisingly not that difficult (except on stainless which is a real pig). I havent got any dies yet, got some coming in the post, and then I've got to make a tailstock die-holder.

If you think single point threading is difficult, in woodturning you do "thread chasing", this is done by hand and, on my lathe, the slowest speed was 200 rpm and so trying to shift the threading tool by hand and in sync is unbelievably hard. Then try doing this repeatedly about 6-8 times to completely form the thread, every time without messing up the existing threads, and at the end of it all you find that the newly formed threaded item is just slightly too small and you have to start over 

Threading on an metalworking lathe is made so much easier with the leadscrew.

Keep trying, it's not that hard. (it cant be, I can do it )


Tim

[CrewCab]

I've done a little single point threading, it's just I find it somewhat trial and error to get the depth correct, and with a metric lathe a threading dial indicator doesn't really work, so a bit like Bogsie's view of the independent 4 jaw chuck, life is too short .................. just my 2c worth mind .......... doesn't make it right 

At the end of the day, if we enjoy what we achieve and swap a few ideas about then that's why we're all here.

CC

[sbwhart]

I have already got about half the materials  I will have a couple of inbetween projects to do though, I need to make a belt drive for my mill, and then a flycutter, and a few more little helpful bits.

You've caught it, you've caught it, you've caught it

 

You are doing well picking up, or working out the basics   

A bogstandard engine is really on the cards.

Stew