Teeny Tiny - My 3rd build Elmer's tiny at 1/2 scale

[90LX_Notch]

I completed my third build today. It was a very frustrating build. Drilling tiny holes on 15" 1/2 hp drillpress without an x-y table is not very fun (snapped a few bits). Amongst the many lessons learned during this build I learned that I need a milling machine.

Now that it's done and runs, I have to say the little !@#$%!@ brings me great satisfaction. ;D In the end this has been a great experience.

Thanks HMEM,

Bob

edit - 3/27/09 - Added pictures with original "Tiny"


[ame]http://www.youtube.com/watch?v=01XnDxemuCM[/ame]

 

[speakerme]

Wow, Nice Job,

That one is a little screamer!

By all means get yourself a milling machine!

Best Wishes


Chuck M

 

[Shopguy]

Congratulations :bow:
Having built a full scale Tiny myself, I can well imagine some of the problems you ran into building to half scale. Good going. Yes, get a milling machine by all means.
Keep up the good work
Ernie J
In Olds, Alberta.

 

[Metal Butcher]

Holy Moly! That's incredibly small!

I'm scaling my builds UP so I can see what I'm doing!

When I saw the still picture on the video screen I thought it was much larger. Then when I saw the parts surrounding the penny I couldn't believe my eyes!

Here's a thought, That penny would make a good base. If you use contact cement you avoid breaking any laws or damaging the motor, and old Abe won't mind a bit!

Excellent build! :bow:

-MB

 

[90LX_Notch]

Thanks everyone. In the video it was running around 7 psi. I have run it down to 2 psi and still looks like it is zipping along. I'll try to get video of it running off of my big compressor this way there won't be any noise, just the engine.

Metal Butcher - I know what you mean about not being able to see. Now that I am over 40 I can't see as well up close. That was a big part of the frustration in building this one. I like the penny idea. The column is tapped with a 2-56 thread from the bottom. I might just have to drill through old Abe.

Shopguy- Lets just say I made a lot of little "fixtures" to aid in this build. I also had to wind my own spring. (Try and find one that small.) Same with the air line. It's a 1-72 screw with the head removed and drilled .040 thru with shrink tubing attached.

 

[bentprop]

What a little cutie,Bob.My hat's off to you.I would have trouble seeing some of the parts,never mind making them.Well done,that man! :big:

 

[Maryak]

Bob,

What a little ripper :bow: :bow:

Loved the sleight of hand with the coin. :bow:

Gotta be worth more than that. :

Another Bob's two bobs worth.

 

[90LX_Notch]

I don't know Bob. Maybe 2 cents?

 

[gbritnell]

That's a great build Bob but most milling machines won't help you out much except for positioning. By that I mean most milling machines don't have the rpm to do tiny holes, that's not saying that you can't drill small holes at a slower speed, I do it all the time. For small holes like steam ports you need something that will spin at least 3000 rpm. I made an attachment that clamps to the spindle of my milling machine that holds my Dremel grinder so that I can do the ultra small holes.
gbritnell

 

[Macca]

Fantastic!
I've been meaning to get my full size version of Tiny finished. This might be just the kick in the pants that I needed.
Well done for completing such a small build, any chance of seeing some of the fixtures you used?

 

[90LX_Notch]

gbritnell- That's good advice. I did the real small holes at 4250 and 6500 rpm. To line up on my prick marks I had to keep moving the vice by striking it with a chunk of brass. It takes forever to get everything lined up to where there isn't any deflection on tiny bits.

Macca- If I get a chance later I'll take some pictures. They are nothing fancy or elaborate; just some simple ideas I had to make holding the parts easier. That's why I posted the word fixture with quotes around it.

 

[kvom]

That one is worth a karma point :bow:

 

[rake60]

Make that TWO Karma's!
My eyes could never work to that scale.
Great work! :bow:

Rick

 

[90LX_Notch]

Thank you gentlemen for the karma points. It really means something coming from the people on this board. I am adding a couple more pictures to the original post.

Also- I shot a what I hope to be nicer video today. I'll probably get it up within the next couple of days. It takes forever to edit it, convert it and post it.

 

[90LX_Notch]

Macca

Here are my "fixtures".

The biggest one is my dog drive plate with a 1 and 1/4 weight lifting plate bolted to it that I used to machine the face on the column of both "tiny" and "teeny tiny". The column was bolted to it through the crank bore to allow the face to be machined perpendicular to the bore. The aluminum plate with the brass pin, along with the drill jig, was used to hold the column perpendicular to the crank bore to drill the pivot hole and the ports. The brass rectangle with the two pins next to it is the drill jig. This is the same as the one for Elmer's tiny except the dims are cut in 1/2. Disregard the two large holes. You can't see the actual jig holes in the picture. They are located in the black area along the right hand edge. The round with the set screw the "fixture" I used to face both ends of the cylinder block as well as bore it. I don't have a 4 jaw and I don't trust my drill press enough to bore the block parallel. The hole is offset to allow the bore to be machined in the lathe. The piece of brass with the screw was used to make the air nipple out of a 1-72 screw. The screw to be machined is inserted in one end and the the long screw is tightened against it from the other end. This prevents the screw being machined from moving and can be set at any length from the brass. The lone rod is a piece of .032 music wire used as a lap for the crank bearing. The rectangle and rod next to it were used to press the crank bearing into the column.

 

[shred]

Did you cross-drill the cylinder pivot pin? That's already a small hole on the original... :bow:

 

[90LX_Notch]

No, not on this one. The pivot pin was one of the last pieces I made and I was sick of small drills by then. Also, around here it is very hard to find very small drills. I would have needed something around .015. However, I was just looking through an old thread about shop made tools and got some ideas. Just for shits and giggles I may duplicate the pivot pin and see if I can do it. In the past I did them in the drill press off of scribe marks and prick punches.

 

[itowbig]

wow thats small little bugger. i have found very small drills in the welding shops they are for cleaning the torch tips out. theres no way i could build that small i cant see those smal things

 

[rickharris]

You can get very small - sub 1 mm drills for Printed circuit board work. With luck you can find reground carbide drills at reduced cost.

In the UK rapidonline.com is a good place to start but all the electronics houses sell these small drills generally with a shank suitable for a dremmel.

Rapid go down to 0.5 mm for carbide at £2.35 each They are tough, we let the kids drill PCBs with them.

 

[ChooChooMike]

A teeny-tiny Tiny !! Very cool !!! :bow: