Stirling Fan

[Deanofid]

You did a nice job on those blades, Doc. They look very good.
I don't think you need to curve them unless you want to. They will
push air well the way they are. Actually, I think they look nice flat.
They do go well with the shiny alu hub, too.

You're getting pretty close on these, aren't you?

Dean

 

[doc1955]

Thanks Steve and Dean
After rigging up a forming jig and making a practice blade and forming it I compared it to the flat blade and I think I'll keep them flat.
So I took a little detour this evening, but some times you just need to see before you decide.
So now tomorrow I'll set down and start polishing the blades so I can get them put together and pinned.
No stainless screws yet hope I get them soon. I do have a few things I need to address yet.

 

[doc1955]

Well I finally was able to get a little done on the project again yesterday. I strayed from the blades and went back to the base to finish. I know I have this tendency to jump from part to part. But that's what I like about working on my own projects I can work on what ever I feel like for the day and think about what I'll do next.
So here is what I got done yesterday.

First off I tilted the mill head to 11 degrees.

Then attached bases to a small knee to scribe center marks on the base. Then flip knee 90 degrees and scribe center again. Now I have centers 90 degrees from each other to use in setting part up for drilling.

Squared up the center lines with a square against the vise jaw.

Pick up the center line scribe mark and the scribe mark from outside dia in with center drill.

Center drill base.

I don't advocate the following step as I was always taught never put an endmill in a drill chuck but in this case I am only putting a small spot face to keep drill from walking off.

Then finish drilling holes.




Now to tram the head in and move onto the next task.

 

[doc1955]

Did a little this morning.
I worked on the displacer rod and bushing. I changed material of bushing to graphite since I had some 3/8 dia laying around from a previous job.

Just basic turning turned up the outside diameters to a press fit to the displaced head. Will drill rod hole after pressed into place in the displacer head.

Here bushing is pressed in place used the mill vise for the task.

Mounted in a 5c collet on the lathe and center drill, drilled and reamed hole to finish size for rod.

Here rod in place I also changed rod material from drill rod to brass.

Next I started cutting gasket material. I purchased graphite with ss insert. If I was to do it again I would of went with material without the ss insert. This stuff is hard tio work with. I needed a small gasket punch and wanted some material a little on the tuffer side. Just so happens a framing nail was about the right size.
So I grabbed a nail faced off the point turned the od on the ent to slip with the holes in the displacer head. Then drilled hole in end about.03 smaller than the od and used a counter sink to bring edge to a sharp edge.

It actually works pretty good even with the ss insert.

 

[doc1955]

Still on the fence about if I want to form the fan blades or leave them flat.
To make a form tool or not to is the question at hand. ??? ???
I need to get going on this build the honey-do list I hope is coming to an end between that and work have not found a lot of shop time that is home shop time, work shop time tooo much! :big: :big:

 

[Deanofid]

Still watching, Doc. I wasn't around for about a week, so missed a few things.
I'd leave the fan blades flat!

 

[ksouers]

Doc,

Good to see you back in the shop.

If I waited for the honey-do list to be completed I'd never get anything done :
Seems when I finish one thing, she adds two more :-\

 

[Maryak]

If I waited for the honey-do list to be completed I'd never get anything done :
Seems when I finish one thing, she adds two more :-\

Oh Kevin,

You don't know how good that makes me feel. I thought I was alone. ;D

The down side of being retired is I'm no longer a moving target.

Best Regards
Bob

 

[doc1955]

The down side of being retired is I'm no longer a moving target.

Best Regards
Bob

Rof} Rof} Rof} Unfortunately I was hit again! And I am still in the working group apparently I just done move fast enough *club*

 

[doc1955]

Some of you may already know but I had a little mishap.
I did get the fan blade put together and pinned and I decided to start assembly.
Well in the process I was called away AGAIN buy my significant other and when I returned to what I was doing I forgot had I taken the bolts out of the top to shorten them.
I picked up the motor turned it upside down and was putting some things together on the bottom side when disaster struck and the cylinder head and crank displacer all hit the floor. Ended up breaking the graphite bushing and bending the displacer rod so now I need to try and get the displacer and displacer head and rod dis assembled to get a new rod made and put into place.

I think tomorrow I should get some shop time and I'll attempt to heat the displacer up to release the loctite and try and get the parts separated.
I'm thinking of chucking in a 5c collet and set lathe rpm as low as I can and heating it up with a torch that way the heat should be even.
Wish me luck I really don't want to have to make the displacer over.
Well at least I like haw the blades turned out I did leave the blades flat and am happy with the look.

I'll try and get some pictures posted tomorrow.

 

[arnoldb]

Good luck Doc !

Regards, Arnold

 

[doc1955]

Here are some of the photos of the last parts made that I didn't get posted.

Here is a rod end blank being prepared.

Dialing ind end to center it on the mill.

Here I'm using a boring head and turning the boss round on the mill.

Drill hole for rod shaft.

Rod end mounted on the shop aide that I've used a few times now made back when I was building the walking beam engines.

Here I have the blade mounted into the hub and clamped in a 5c collet block to drill pinning holes.

Blades pinned and done.

Then I started putting things together and that's when it happened :toilet: pieces hit the floor.
So next I need to get the displacer parts taken apart to remake shaft and bushing.

 

[Deanofid]

Yes, those fan blades look great, Doc! So sorry to hear about the mishap with the
other parts of the engine. A crummy thing to happen to such a nice guy.

 

[doc1955]

Thanks Dean!
And big thanks to you Arnold it worked got the parts disassembled without any damage to anything.

I chucked the displacer assembly up in the lathe and turned at the slowest speed while heating with a small butane torch. I was just about to give up when it got hot enough for the loctite to release. It worked like a charm.

Here are the parts all disassembled.

So now I can get started making a new bushing and connecting rod.
I'm thinking since I don't have another piece of graphite close to the right size I'll make it out of acetal or also known as delrin since I have that on hand.

 

[Deanofid]

Doc, I have some extra graphite here. If you want some to make a new part, let me know and I can put it in the mail Monday morning.

Dean

 

[zeeprogrammer]

Nice looking blades Doc.
A couple of mishaps and you don't miss a beat...you make it seem like part of the process.

 

[b.lindsey]

I'm happy the damage wasn't worse doc and that you have recovered most of it. Am really looking forward to seeing it run!

Bill

 

[doc1955]

Dean thanks for the offer!
But the plans did call for acetal the graphite was one of my deviations.
I think I'll make it to plans and table the graphite. I will be ordering some other stuff from Enco so I'll order some of the sizes I'm missing for stock. I like to keep a little of the various sizes on hand.
But thanks again for the offer.
Now to head out to the shop and get some stuff done before I get side tracked.

 

[doc1955]

Well got the bushing that I broke replaced and turned up and fitted the piston and set the proper length of power connecting rod.

Piston blank turned up ready for wrist pin hole.

Wrist pin hole drilled. Next mill rod end pocket.

Milling pocket.

Piston done.

Setting rod length.

Setting length bottom of stroke with a .025 feeler to set clearance.

Try for a run tomorrow keeping my fingers crossed. If things go well and I get a runner will get the second fan caught up and design up a flame guard and do some final polishing before final assembly.

Well we will see what tomorrow brings.


PS Was a good day to spend in shop today the high temp for the day was 12f degrees with snow blowing around. Suppose to be the same for tomorrow so I shouldn't get any interruptions. :

 

[doc1955]

Well things went well first run took some time to heat up but once it was up to temp took right off and run until all the fuel was gone and it cooled down (about a half hour). The cooling fins were only slightly warm to my amazement.
Let it sit and cool off for about 2 hours and set up the video camera and taped the second run. Here is the video of that run.

[ame]http://www.youtube.com/watch?v=_-0ZyovOqnE[/ame]

now I need to create a heat shield and flame guard and give it a final polish and maybe work on a different lamp. I'm a happy camper need to also get second fan finished. For the flame guard I'm thinking of using some brass screen I happen to have laying around we will see.