Building of TINY INLINE 4 in Brazil

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Hello everybody!
Some more work done on the building. This time I was able to finish the valves.
First I turned the valve stem to the right dimension. On the same set up I also machined the head chamfer to guarantee the concentricity between the stem and the chamfer surface. Doing that I think I reduce the chance of bad fitting of the valve chamfer and the valve seat chamfer on the head.





Here you can see the compound slide set to 45 degrees


Using the same set up in order to guarantee the same valve angle I also turned the tool for the head valve chamfer seat




Then I took the tool to the milling machine to make the cutting edges. I made four flute


the tool in action providing the valve seat chamfer on the head








Making the collet to machine the clip groove and machine the extra material off the head.


Turning the valve keeper (clip) groove






Machining the extra material off the valve head




Valves finished






I used automobil lapping compund to lap the valves with the head seat. Grosso means Coarse and Fino means Fine


I then used a small Dremel to lap the valves




The head with the finished valves on it


Next I plan to finish the camshaft. I already machined the blank. It is only missing the lobes and the thread for the distributor gear.



Tanks

Edi
 
Caramba... trabalho de relojoeiro... parabéns... da gosto de ver ED
 
Hi Edi,

Still having problems converting my mill and being away last week has cost me more time

Will get to it this weekend :)

Mike
 
Hi to all,
Not much work since last post. I only worked on the camshaft blank machining the lobes on it and grinding the journals for the bushings.

Here you can see the blank at the milling machine. I used the CNC for this operation.








Finished the lobes. It took me about 2 hours to machine the 8 lobes


I still need to do the fine finishing with a file and sand paper


Next I set it between centers to grind the journals for the bronze bushings




Here I`m grinding the 3mm diameter for the distributor gear. I ground the three diameter on the same set up to guarantee the concentricity


Almost finished camshaft. Still missing the 2,5mm thread on right end for the distributor gear




Here I`m turning the front camshaft bushing




The rear end bushing on the lathe




The bushings on it`s place




The bushings




Like I said before, not much work, but I`m getting there.

TKS,

Edi
 
Hi Edi,
Just a suggestion.
When cutting a cam lobe with the end mill sitting on center it produces a crown on the lobe equal to the clearance angle of the cutter you're using. If that's the way you are going to make your lobes it would be better to grind the end mill flat on the bottom. Better yet it would produce a nicer job if you would step off the lobes, down in Z over in Y, down in Z, over in Y. It would also reduce the amount of hand work to finish the lobes.
Attached is a sheet I had drawn for the way I design and machine a cam. I don't know whether I had posted it before but if not here it is again.
gbritnell

View attachment CAM LAYOUT DRAWING.pdf
 
Hi George!
Tank very much for your tips. It will be very helpful next time I will test following your advice.
You are right it produced a crown around the lobe profile

As I have a CNC milling machine, over the years I was thinking how I could use it as a adapted cam grinding machine.
I had a small tool post grinder sitting around then I adapted it to the milling machine removing the gear head and fixing the tool post grinder in the place of the gear head.
I think that the potential of it to work is high once I need only two axis moving, the fourth axis rotating and the Y axis moving forward and backward.

See some photos bellow.









I still did not test it. Because I need to generate the G code for the lobe grinding.
As I remember someone posted something about a free software to generate the G code using the `Y-axis and fourth axis movement but I cannot find it here again.
I may try to generate the G code on the MasterCam, however it demands expertise on 3D features of the software which I don`t have.

Edi
 
Hey im in the process of build this same engine i bought the plans and i was wondering how do i make spark plugs or how did you do it its confusing thanks
 
I had a small tool post grinder sitting around then I adapted it to the milling machine removing the gear head and fixing the tool post grinder in the place of the gear head. Edi

I like your tool post grinder. Can you tell me more about it? Did you make the spindle yourself, or was it a commercial unit?
 
Hey im in the process of build this same engine i bought the plans and i was wondering how do i make spark plugs or how did you do it its confusing thanks

Hi Jesse!
I machined the body on a small CNC lathe. I wrote the G code and machined 10 parts from a 1/4' hexagonal bar, then I took it to the milling machine holding the body with the rotary head to machine ground strap. Please take a look on post #99

I hope I helped. If you need any help during your building, feel free to contact me. Count on me.


Edi
 
I like your tool post grinder. Can you tell me more about it? Did you make the spindle yourself, or was it a commercial unit?

Hello Petertha,
The post grinder is commercial; in fact it is a optional from a small Chinese lathe I purchased years ego.
The bearings are not for high speed use so I will replace them to a better quality ones.

Edi
 
Hey edi thanks i will try that i was wondering what is that tool called that is in you milling machine that you used to cut the crankshaft bearings in half thanks
 
Hey edi thanks i will try that i was wondering what is that tool called that is in you milling machine that you used to cut the crankshaft bearings in half thanks

Hey Jesse!
If you are talking about post #100 and #103, it is an end mill 4mm diameter. The fllowing pictures shows the grinding wheel grinding the bearings.

TKS,

Edi
 
Could you tell me what number gear cutter you use for the 12 tooth 48DP bevel/miter gears for the distributor?
Thanks!
 
I ordered these prints from the fellow and never got them!
Alec Ryals
 

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