Building of TINY INLINE 4 in Brazil

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As I mentioned before, I would like to show you the result of a test I did for machining the crankshaft on the milling machine with cnc.
For a long time I was thinking how I would machine the crankshaft without having many failures. A couple years ago I saw a video showing a six cylinder model engine crankshaft being machined o a milling machine, then I thought I could use my CNC milling machine to do the job, at least to do the rough job, leaving material for final the pass on the lathe or on a grinding machine.

Here is the video I`m referring to.

[ame]http://www.youtube.com/watch?v=NV1ZOzAaXbo[/ame]
As you can see on the video the blank was fixed on the dividing head (I think it is a rotary table on vertical position) with a device. For the pin throw, the device was moved of center and the milling head (z axis) was fixed.

My idea was little different. I wanted to use the CNC resources I had on hand generating a G code that would move the machine head with the blank fixed on the center of the dividing head (circular interpolation) but using the Z axis.
I use the Mastercam Software to generate my G codes. With the help of my Mastercam teacher *discussion*, we produced some tests shown on the videos bellow.

I was right about my idea. The test worked fine Thm: only need some fine adjustments to eliminate unnecessary movements.
In order to avoid any "probably" damage to the machine or to the tool caused by a mistake, I run the test on a wooden blank.

First video shows the center bearing being machined. As the width of the bearing is 5.59mm and I used a 4mm end mill it was necessary 2 passes.
[ame]http://youtu.be/CwQQ9UtWpCE[/ame]

The second video shows the crank pin being machined. Observe the movement of the Z axis.
[ame]http://youtu.be/w95zgWEtOkU[/ame]

I`m really happy with the result, now I can start machining the real crankshaft on a 01 steel blank.

I also used the same idea to machine the camshaft. It also worked fine. I don’t have the video because I screwed the blank due to a mistake :wall:*club* on zeroing the axis. I did a second test but no video was generated.
When machining the real camshaft I will make a video.

Well, one more step reached in direction to a running engine "I hope"

Thanks for watching and I hope you liked this.

Edi
 
Wow! Looking really good! Can't wait to see how your crankshaft turns out. I'm getting closer to starting mine, unfortunately for me I don't have the luxuries of a CNC. I'm thinking about mounting my Sherline lathe on the table of my Bridgeport mill and ruffling it out with a end mill. Good luck on your progress!
 
Awesome work. Subscribed.
Looking forward to the real crank video.
 
Hi all!
Regarding finishing the centers and throws, and considering that I don't have an OD grinder, for a long time I was thinking if I could do some grinding on the milling machine. So, I started working on a project to adapt a small toll post grinder on the milling machine.
I already did some tests to see how it would fit on the milling. It showed to be very feasible.
My first option is to use the configuration as a CNC grinder, however if it does not show good result or to complicated to operate, I still can use it as a manual OD grinder.
I will post this evening some photos of the machine with the "grinder device" and the modified tool post.

Thanks,

Edi
 
Well as said on last post here are more details about my test adapting a toll post on the milling machine.

These first photos show the device on top of the bench for you to have a idea on what I will explain.





As you can see on the photo I used a square device (gray) to fix the tool post grinder. I machined a disc to fix the grinder on the square device (it came with the machine as a fixture to hold a hole grinder).
This device goes in the place of the milling head (see photo later)

In order to adapt the toll post grinder I had to modify the position of the motor because it was conflicting with the square fixture. The motor plate holder was cut on a laser machine 3mm thickness plate. The motor was moved to the opposite side from the original position. See the modifications on the photo bellow.


Bellow you can see photos of how it was fixed on the milling machine.






Here is the head of the machine that was removed from it.


I still did not test it in running condition. In theory it should work. In some cases what is so evident on theory, does not work when it is submitted to real work.
I will be testing it on the camshaft and crankshaft.

I hope you liked that and I was clear enough (with my mechanical English vocabulary limitation) to pass you all the details of what was done.

That's it guys.

Edi
 
As I mentioned before, I would like to show you the result of a test I did for machining the crankshaft on the milling machine with cnc.
For a long time I was thinking how I would machine the crankshaft without having many failures. A couple years ago I saw a video showing a six cylinder model engine crankshaft being machined o a milling machine, then I thought I could use my CNC milling machine to do the job, at least to do the rough job, leaving material for final the pass on the lathe or on a grinding machine.

Here is the video I`m referring to.

http://www.youtube.com/watch?v=NV1ZOzAaXbo
As you can see on the video the blank was fixed on the dividing head (I think it is a rotary table on vertical position) with a device. For the pin throw, the device was moved of center and the milling head (z axis) was fixed.

My idea was little different. I wanted to use the CNC resources I had on hand generating a G code that would move the machine head with the blank fixed on the center of the dividing head (circular interpolation) but using the Z axis.
I use the Mastercam Software to generate my G codes. With the help of my Mastercam teacher *discussion*, we produced some tests shown on the videos bellow.

I was right about my idea. The test worked fine Thm: only need some fine adjustments to eliminate unnecessary movements.
In order to avoid any "probably" damage to the machine or to the tool caused by a mistake, I run the test on a wooden blank.

First video shows the center bearing being machined. As the width of the bearing is 5.59mm and I used a 4mm end mill it was necessary 2 passes.
http://youtu.be/CwQQ9UtWpCE

The second video shows the crank pin being machined. Observe the movement of the Z axis.
http://youtu.be/w95zgWEtOkU

I`m really happy with the result, now I can start machining the real crankshaft on a 01 steel blank.

I also used the same idea to machine the camshaft. It also worked fine. I don’t have the video because I screwed the blank due to a mistake :wall:*club* on zeroing the axis. I did a second test but no video was generated.
When machining the real camshaft I will make a video.

Well, one more step reached in direction to a running engine "I hope"

Thanks for watching and I hope you liked this.

Edi

I like your idea with the CNC it will work just need to get the code right I'd say. Now if I may my last job was a GM crank line our first op was to drill both ends and tap the holes all with CNC. The second was rough the pins we had a circular insert mill that rotated to cut the undercuts and the pin to size. The CNC was programmed the move from pin to pin and the cutter would move up and down as the crank rotated. There were other thing done but that was it till finish grind with a pink I thing gel wheel they lasted a long time between changes. I hope I get this to work out for you.
Ps. May want to try circular cutter in this case a circular saw the right width for your crank they seen to cut smoother for us.
Todd
 
Hi, My name is Deepak. I am from India. I would like to the the plans for your inline 4 engine.
Plz email me.
Cheers Deepak
 
Hi, My name is Deepak. I am from India. I would like to the the plans for your inline 4 engine.
Plz email me.
Cheers Deepak

Hello Deepak!
I may find all the information on how to buy the Tyne 4 Inline plans on the link bellow.
http://www.homemodelenginemachinist.com/f12/tiny-inline-4-cylinder-ic-plans-sale-14833/

This engine was disigned by Kcmillin and you can find a complete log of his building on the link bellow:
http://www.homemodelenginemachinist.com/f31/tiny-inline-4-cylinder-ic-10240/

I`m pretty sure you will enjoy building it. The plans are well detailed and in case of any question, is just a matter of sending an e-mail to Kel and he will reply to you very fast.

Edi
 
ola amigo sou de santa catarina e estou fazendo uma lancha de 1.80 rc, e precisava de um motor deste, você esta usando projeto para a construção. valeu.

[email protected]
 
Hello all there!
It's been a long ,time since my last post. I have spent several hours testing the CNC machining operation for the crankshaft. I machined a complete crankshaft on a wood blank to complete test the program. It worked well in terms of G Code just a few unnecessary G0 moves but nothing that affected the final result, just added some minutes to the operation. I will show you pictures and videos of the test.
I also tested the program for the camshaft. It also worked well, this time I tested on a aluminum blank. Again unnecessary G0 movements appeared here. I was not able to remove it from the program.

After my incursions on the CNC field, I made some progress on the Tiny 4 inline project.
I have machined the crankshaft, main bearing bushings, spark plugs and the connecting rod bearing bushings.
I also touched the carburetor. I have done the lathe operation for the body.
Pictures and videos are coming.

Thanks,
Edi
 
As I said, on previous post, here are the pictures of my progress on project.

Turning the spark plug body


Machining the opposite side for the isolator


Milling the the end for ground tip



The electrodes with brass contact soldered


Here is the isolator made out of Corian



This is it for today. The internet link is not helping at all today.
More pictures this weekend.

Thanks,

Edi
 
OK. I think I got a good internet link now.

What I want show you is the crankshaft machining on the milling machine.

Preparing the blank


First I machined the crankpins


Than the center bearings



In order to avoid the get a warping during the milling operation, I have shimmed the crankpins space with a brass washer as you can see on the photo bellow.



Finished the milling operation. Now the idea is to take the crank to the lathe for the grinding operation


I fixed it on the lathe between center. With a small toll post grinder I did the grinding first on the center bearings (what I found lather being a mistake) I should have done first the crankpins because I got a small warping when grinding the it so I had to regrind the center bearings and the ends.
Opps! The grinding wheel you see is a Borason with 4mm thickeness.



Finished the center bearings and the ends.


For the crankpins grinding I did something maybe different than you guys are used to. I Prepared a device (two pieces) with center holes displaced with the same dimention of the overthrow. The pictures will explain better than my words.




Getting the center of the hole
[URL=http://s1266.photobucket.com/user/epicler/media/2014-08-30%20Virabrequim/DSCN2534_zpsea920027.jpg.html]

DSCN2532_zps91f4f3ca.jpg
[/URL]

Next I fixed the devices on the each end of the crankshaft and centered it with hight gage on the granite block




Moved it again to the lathe for the grinding of the crankpins fixing between center as I got the centers with the devices on the ends


Finished crankshaft


Next job was to make the center and ends bearings



My first idea to split the bushings was milling off half of it so I would get a perfect bearing. Surprise!! It was a disaster, the end mill destroyed the piece, I think it was too thin for this type of operation.



I decided to use a circular saw with 0.6mm thickness for this task. It worked perfectely


The bushings mounted on the journals





OK guys that is the report of my progress so far. Lots of learning. Getting KnowHow!!!

Thanks,

Edi
 
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