Fairbanks 80HP 3 Cylinder Model

[aonemarine]

Chuck the more you use Alibre the easier it gets. I dont know how your making you parts but for the fly wheels i found it easiest to draw the outer rim and extrude it to thickness, then extrude remove the inner details.

 

[mikegw1961]

Chuck

I found the easiest way to learn Alibre is to practice on something you already have drawings of. I have taken 4 different engines and drawn all the parts in Alibre and then assembled them

Now I have a better understanding of how it works. Trying to design parts and figure out how to draw them is very hard

I hope this helps

Mike

 

[Dave Sohlstrom]

Chuck

Have you updated to Alibre 2013 now named Geomagic design ( dumb name).

It has lots of new stuff.

Engine is looking real good.

Dave

 

[cfellows]

Thanks, everybody, for the tips. Dave, I haven't upgraded yet, but have been seriously considering it. Are you talking about Geomagic Hobbyist edition?

Chuck

 

[Dave Sohlstrom]

I run Pro but yes on personal it was upgraded also.

Dave

 

[cfellows]

Spent the day today getting the flywheel pieces ready for milling the spokes. I have an old Atlas 4" 4-jaw chuck which I attached to my small rotary table so I could hold the flywheel centers for the milling operation.

Here is one of the 4" x 4" x 3/8" aluminum blanks for the flywheel centers.

And here's what they look like with the corners cut off.

I applied some adhesive backed sandpaper to my 5C collet holder and mounted it in the lathe.

Then mounted the blank in the lathe with a live center pressing it against the sandpapered collet chuck.

Here's the two blanks after they're turned round.

I scribed circles showing where the recess will be turned. If you look at the inside of the steel ring, you can see a shallow shoulder near the bottom. The aluminum blank will rest on this when assembled.

After cutting the recesses, I centered the blanks in the 4 jaw chuck on the rotary table.

After centering the spindle over the centet hole in the blank, I moved the work in the Y direction about .28". This positions it to make a radial spoke cut leaving about .030" extra meat for later clean up. A few notes here. The end mill is a 1/4" HSS roughing mill. The spokes on these flywheels will be straight since I like straight spokes better than tapered and the Fairbanks looks to have straight spokes. They are also easier to make, since I can make all the radial spoke cuts without repositioning the rotary table.

I positioned the cutter over the inner extreme of travel and set the right X-travel stop.

Then I cranked the table to the outer travel limit and set the left x-travel stop.

Here's a peak at the table lock which prevents the table from rotation during the milling operation.

And here's an overview of the setup I'll be using tomorrow to make a video of the spoke cutting operation.

That's it for today.

Chuck

 

[aonemarine]

Thanks for that Chuck, I learned a few new tricks.

 

[cfellows]

Got most of the work done on the flywheels today. Also took some videos which I'll have to edit and put together over the next few days. Didn't go as smooth as I'd hoped and made me realize I didn't have everything figured out.

I still have some additional shaping and finishing to do, but you'll probably notice right off that the spokes on one are thinner than the other. The thicker spokes were what I had designed, but I think I like the thinner spokes better. Anyway, my options are 1) leave them alone and use them as they are, 2) cut the thicker ones down to to match the thinner ones, or 3) remake the thinner one to match the thicker one. I'm leaning toward 2 and number 1 is really not an option, but will have to think about it.

Chuck

 

[aonemarine]

The thicker spokes look kinda blockey....Blockey, is that a word?? Oh well if not, it expresses my thoughts...

 

[cfellows]

The thicker spokes look kinda blockey....Blockey, is that a word?? Oh well if not, it expresses my thoughts...

Yeah, I think blockey is a word. Maybe it's blocky? Either way, I know what you mean. Gonna save me a lot of work if I just thin down the thicker spokes.

Chuck

 

[Lawijt]

So nice Chuck , it looks so easy........NOT!!!
But why you make the flywheels?? There are so much beautifull casting flywheels...
I follow this absolutely. I learn much from pictures.

Best regards

Barry

 

[cfellows]

So nice Chuck , it looks so easy........NOT!!!
But why you make the flywheels?? There are so much beautifull casting flywheels...
I follow this absolutely. I learn much from pictures.

Best regards

Barry

Thanks for the comments, Barry. The Fairbanks engine I am modelling has an 8-spoke flywheel. These are not commonly available anywhere that I can find. Also, most sources for flywheels are very expensive, particularly when you include the cost of shipping. I don't much like making them, but there doesn't seem to be any real alternative that's affordable.

Chuck

 

[cfellows]

Thanks, everybody, for the comments and helping me decide on the thinner spokes. I thinned down the spokes of the second flywheel. The aluminum centers are a very close fit in the rims, enough so that I couldn't quite press them in with my fingers, but could easily work them in with my arbor press. I was originally going to heat the rims and cold-shrink them over the centers, but I got the fit just a bit too loose. So, I opted for Loctite 620 which I think will be more than enough.

I Loctited the pieces together today, then began cleaning and shaping one of the wheels. Here is how it looks so far...

I'm including this second photo because I thought it was kind of neat and shows the contour of the flywheel quite clearly...

I still have to install the hubs and I'll probably use Loctite for those as well.

Chuck

 

[Wagon173]

This loctite seems to be something I need to pull out of my tool box and set on my bench. You aren't the first one I've seen posting about using it to secure things. I guess it makes sense though. If I had a dollar for every bolt I've broken because someone used more than a few drops of the stuff on a previous job... *knuppel2*

 

[Lawijt]

I understand that Chuck. Those are very heavy and will be a lot of shipping coasts. But when I see it now , it looks great.

 

[cfellows]

I've got the flywheels pretty much finished. The loctite is drying on the second one at the moment.

I decided to use shaft lock hubs that I've had good luck with in the past. A bit more trouble to make, perhaps, but I had to make some kind of hub and these work well. First a picture of the finished flywheel (unfortunately I took these pictures with my iPod and the quality sucks)...

To make the hub, I started with a length of 3/4" diameter cold rolled steel. Would have preferred 12L14, but this is the best I had on hand.

I shouldered down a 1/2" length to 3/8" diameter drilled a pilot hole through the center...

After drilling it out with a Letter N bit, which is a bit smaller than 5/16", I mounted it in my milling vise and cut a radial slot through the shoulder through to the ID.

Next I used a 3/16" end mill to cut a a hollow in the shoulder, then drilled and tapped all the way through for a 4-40 socket head cap screw.

I apparently did not get a picture of the next step which is to cut a slot perpendicular to the slot across half way through the smaller diameter next to the shoulder, perpendicular to the radial slot. Perhaps the attached Alibre drawing will make it a bit clearer.

Here's a closeup of the Hub loctited into the flywheel...

Chuck

View attachment Flywheel Hub.pdf

 

[aonemarine]

Wont be long now and it will really start taking shape. Looking good Chuck!

 

[cfellows]

Wont be long now and it will really start taking shape. Looking good Chuck!

Thanks! I appreciate the comments and support.

After finishing the flywheels, I got started on the cylinders. Started with 3 chunks of 12L14 steel, 1 5/16" diameter x 1 3/4" long.

Bored and reamed them to 3/4", the final bore size (so far ). Also shouldered down the bottom to fit in the cutouts in the upper crankcase.

Man I love working with 12L14. So nice to machine.

Chuck

 

[aonemarine]

12l14 is nice to machine and great for models. You can all most feel the bit of lead in it when you cut it.

 

[cfellows]

I dove into the rotate boss function of Alibre tonight and managed a respectable drawing of the cylinder, curves and all. I would call it a rotational extrusion. See the attachment for a 3D representation.

Chuck

View attachment Cylinder2.pdf