Stirling Fan

[doc1955]

Thanks Larry I just hope they are runners when I finish stirling engines shake my confidence if they were internal combustion engines I would feel a little more confident in having a runner.
Thanks again everyone for the kind comments!

 

[shred]

;D I bolted the blades to my fan hub for much the same reasons...

 

[doc1955]

Well it's been some time since my last up date sorry about that but the weather here has bee less than desirable for shop work. The humidity and temp have been well above normal.
Here is what I've got so far I did have a little time out there today before it was just to warm.

Started by getting 2 pieces parted off for the top rings.

Chucked them up in a 3jaw and drilled a .5 center hole and bored the ID deep enough so that when I flipped and did the counter bore from the back side they would intersect. Bored the counter bore on the first side then I flipped in the 3 jaw and counter bored the back side.

Then I quick made a little holding jig to drill the hot end mount holes. Clamped up part and moved to the first location and drilled through the part and the jig. Then I moved to the second location and after that just looseness the part and rotate using drill to line up the hole just drilled with the hole in jig. That way didn't need to move the machine table after the second hole plus I'll hole the line up hole in the jig in the next 2 operations also.

Holes for hot end done.

Set the jig up at the 11 degrees put a .5 tooling ball in the center hole to dial in on. I calculated the distance from that center to where the hole for the stand rods needed to be the center of the ball is .500 above the jig at 11 degrees the part is .400 so the center was .1 above the part.

Then set up the jig a 101 degrees to drill the 4-40 holes for set screws to hold the stand rods in place.

I ended up having to make a tap extension to tap the holes.

only thing left to do on these parts is mounting holes for the flame guard.

Next need to round up material for the bottom ring.

 

[Deanofid]

Glad to see you back, Doc!
You got quite a bit done for working in a hot shop. That always slows me down!
Everything's looking great.

Dean

 

[doc1955]

Thanks Dean!
I have a tuf time getting motivated when its hot & humid in the shop.
I see now that this fall a wall will be going up to separate the area I claimed as my shop are from the garage. That way I can install air and keep my machines (and me) out of the hot and humid air.



I am going to put a little some thing here just encase anyone needs to have a tap extension and hasn't tried this it works extremely well and is very easy ans fast to do.


First grab a piece of stock slightly bigger in dia than the tap and drill hole in the end the same dia as the tap and about the same depth as the flats on the tap.

Then simply insert tap leaving just enough of the flat showing so you can see the orientation. Lay on and anvil and take a punch and give it a rap to flaten then flip 180 and give one more rap then turn 90 and do the same. You don't have to get carried away a light tap with a hammer should deform it to form the square drive end.

Then if you want the tap to stay in the drive without holding it there simply magnetize it.

To do that I just grab some old speaker wire wrap it around the extension and ark the wire on a battery a couple times and it will magnetize it for you.

Extensions like this are cheap simple and work very well.

 

[doc1955]

Well got a little more done since last post.

Turned up blanks for crank arm.

Mill oal width.

Turned up a little brass spud to use for filing radius on end and also used to mill the angled sides. I put a parallel laid across the bras spud and the arm spud to line up with top of vise.

Here they are after the filing on the set screw hole is left then they are done.

Rounded up some material for the base rings and laid out the center and center diameter.
Then used a 1/4 end mill and plunge milled around the hole except for the last 1/4inc or so. Want to use the center slug to line up part in 4 jaw on lathe before removing it.

Used center to line up in 4 jaw then removed from 4 jaw removed the slug and put it back in the 4jaw to finish bore the ID.

Then switch to a 3 jaw cl mp on ID and finish turn OD and face.

Here they are diameters finished they are thicker than the drawing call for but that's ok they are 1 inch thick.

Just set the pieces together to let the Noid have a preview. :big:

Next I'll need to create a jig plate to drill the holes at 11 degrees.

 

[kustomkb]

Looking good Doc!

Nice fixturing.

 

[SAM in LA]

Doc,

I learn something everyday.

Thanks for sharing.

SAM

 

[b.lindsey]

Doc,
That is coming along very well. Looking forward to seeing the home stretch and that first run.....keep up the nice work.

Bill

 

[doc1955]

Thanks Kevin,Sam and Bill!
Haven't spent a lot of time out in the shop the last couple months.
I still haven't decided at how or what the fan blades will look like.
I'm thinking of 2 different styles. I have a few little parts to make along with the blade. The fan blade material is laying here ready for me to get off the fence and decide how I want it to look.
Thanks for checking in!

 

[Deanofid]

The base came out looking good, Doc. Neat trick, chain drilling it except for the last hole so you could
use it to center the piece.
Oh, the cranks came out great, too!
This is looking pretty close to being 'there'. Great project. Glad I followed along!

Dean

 

[doc1955]

Thanks Dean I have a few small pieces to make yet.
Plus I still need to finish base so I'll need to get a holding jig made to use to hold them.
Plus the fan blade yet to do. I noticed I don't have any 4-40 cap screws so I think I'll order some stainless button heads for these motors. I seen McMaster has them for 100qty under $10. I was thinking of also ordering some graphite gasket material also I think that material is suppose to be good up to I think around 850f degrees. That should be ok right?

 

[doc1955]

Well it's been some time since my last update. I had some things happen that made me not able to go into the shop. Anyway I did get a little done.

I got some blank hubs turned up for the fan. I went with aluminum and I'm going to pin the blades in place.
I milled a setup block the angle of the pitch of the blades so I could set up against the vise stop and all the slots would come out consistent.
I scribed the center of the hub.

I just eyeballed the center to the slitting saw blade should be close enough.

Then proceeded to cut slots. Rotated collet block and do again all four sides.

Finished hubs if you look closely you will notice slots in one hub are opposite of the other.
Darn it was a mistake I made on the first one the blade will need to rotate counter clock wise.
So now I have one that will need ccw rotation and one with cw rotation. Oh well I think the 2 setting together running with on one way and the other the opposite will look kind of neat.

Next I took and cut the brass blade stock to a width just larger than the finished blade width.I then double taped them together and placed a paper template on top that I plotted full size.

Now ready to cut them to size that will be next time.

 

[Deanofid]

That's so easy to do, Doc, getting the slots going the wrong way. That stuff happens. It sounds
like you have them figured out to make both work.
The hubs look good. Good idea to fasten the blades all together to get them all the same, too.
It should look pretty sharp, with brass blades, and aluminum hubs!

Dean

 

[doc1955]

Thanks Dean
I 'm going to try and get out in the shop and work on the fan a little today.
I need to think about how I'm going to form them the plan calls out a 3 inch radius.
I might make a little form jig to try and get them all the same.

 

[doc1955]

Well I used a gauge block to line up blades in vise and mill to template line.

Did this for the entire profile of blade and then filed radius where needed.

Removed template and ready to separate blades.

Placed them in pan of boiling water to soften the double back tape to separate blades.

Blades separated pretty easy after a minut or so in the boiling water.

Clamped hub in 5c collet in lathe and tapped blades into place. I was worried the slitting saw I had would oversize slot but they turned out to be a nice press fit with the blades

After seeing them assembled to the hub I may not form them into a radius I am thinking of leaving them flat.

I polished up one just to see what it would look like polished.

I'll need to decide about the forming before polishing them.

 

[zeeprogrammer]

Nice!

 

[b.lindsey]

Those look GREAT doc. On Jerry's smaller fan the blades are not curved so it isn't mandatory at all. Very nice job you did on those!!

Bill

 

[doc1955]

Thanks Zee and Bill
I'm still not sure if I want to form the blades or not.
I'm going to polish up one set and see how it looks before making the final decision.
I'm hoping I'll get my stainless button head screws I ordered for these and the insulator material.
I'm getting anxious to start putting things together.
I'm thinking of putting some flat black on the power cylinder and cold air cylinder and then polishing the fins another decision I'll have to make and make it soon.
Thanks again for the comments it is appreciated helps keep one motivated.

 

[swilliams]

I found seeing how to make those fans really interesting Doc. The photos of the slots in the hubs look so much like they have a real curve rather than a straight saw cut. Nice work!

Steve