2021 POTD Thread Archive

[rwm]

I just cut up some rail recently. The top surface is work hardened about 1/8" thick on my material. I cut from the bottom with a band saw and then snapped the top part. You may find the top difficult to mill.

 

[jwmelvin]

I just cut up some rail recently. The top surface is work hardened about 1/8" thick on my material. I cut from the bottom with a band saw and then snapped the top part. You may find the top difficult to mill.

So it wasn’t that bad? I have a four-foot section I’ve thought about using in a couple parts.

 

[rwm]

I can only speak for my material which is trolley rail made in 1922. Only the top surface was hard on mine. I could cut the bottom and the web with a portaband or vertical bandsaw.

 

[Shootymacshootface]

I just cut up some rail recently. The top surface is work hardened about 1/8" thick on my material. I cut from the bottom with a band saw and then snapped the top part. You may find the top difficult to mill.

I wish that I had thought of that when I made my anvil.

 

[wachuko]

Easy does it... holes on the base done... and started to do the rest. As suggested, leaving part of it the way it was and machining the rest...



I was quickly reminded that I have a small milling machine... easy does it. But did I take it easy??? Nooooo!!! Blew a fuse... the machine, not me... Another lesson learned... let it cool, take it easy...

Ordering fuses...I blew the 10 amp fuse... machine has a 10amp (F10AL Fast-Blow Fuse 10A) and a 15 amp (F15AL Fast Blow Fuse 15A)



And heading out to Virginia in the morning... so more on this on Wednesday...

Cheers!

 

[jwmelvin]

Blew a fuse

Looks like nice progress. I would have a perverse sense of satisfaction from blowing the fuse.

 

[GoceKU]

Today i spent few hours working on my friend's niva, this it the one i welded in the seats more then year ago. Its not starting and it's been towed from shop to shop for more than 3 months. No one could figure it closes one come it needs complete ecu and wiring loom but that is more expensive then what its worth. So after testing all the basics and doing lots of wiring loom repairs the ECU come out and found the problem. Water has gotten in and shorted the circuit board. It needs an ecu, but its not as simple as others vehicles it has an immobiliser and it's a separate box made by the russians and needs special programer that no one seems to have. The original ecu is not responding at all, i plan to sent off the original ecu to get fixed. There is a way to cut the wire from the immobiliser box but the ecu has a runtime check and it will lock it self in some time.

 

[francist]

Today’s little adventure was coming up with one of these. A pin puller (pusher? driver? extractor? gizmo?…) to get a tiny split pin out of the rear end of a 1961 Elna Supermatic.



There are a few machine designs that made use of a rubber friction wheel or friction “pulley” as it’s often called to transfer power from the motor to the sewing mechanism and the Elna was one of them. Trouble is, as the machines age and especially if they site unused for great lengths of time (ie: years), the rubber can develop a flat spot where it rests against the hand wheel. It doesn’t kill the machine, it can still sew, but it makes a rather disconcerting thump-thump-thump-thump-thump as you step on the gas. Kind of like those minus 35 degree mornings when the tires on my Dad’s big Buick got rolling for the first time. So gotta replace the friction wheel.



Of course it’s not real easy to get at and everything is small. I measured the split pin as best I could at about 0.090” and built from there. I’d seen someone else’s version of a similar design in use and thought it was pretty clever so I used that as my starting point. There’s nothing really special about the actual machining — I just used a scrap of 6061, a #10-24 machine screw, and a 5/64” drill bit in the end as the pusher.



And it worked great! With hardly more than finger pressure the split pin started easing out the other side until it was completely clear and I could lift the pulley. That is until it ran into the aluminum casting right above it! Grrrr! This is kind of like those car stories where you have to drop the whole motor to change the oil filter but that’s exactly what I had to do — flip the machine over, take off the belly pan, disengage the speed control linkage and drop the motor by an eighth of an inch. Goofy.





Anyway, it worked and it got the pulley off. You should be able to see the flat spot just between my fingers. Coming up with a new one will be for another day. Replacements can be had although I’ve heard the quality can be a little spotty not to mention kind of expensive. I’m going to try casting my own out of some Shore A60 silicone and see what happens.



Thanks for looking!


-frank

 

[brino]

I’m going to try casting my own out of some Shore A60 silicone and see what happens.

That would be something I'd like to see.
Another tool in the bag of tricks if it works!
-brino

 

[sycle1]

Good to see this post Francist
My partner has a few Elna supermatic's a 51, a 56, 2 of the 64 models and a 75 model so interesting to see this about the friction drive pulley .
I may be going down that maintenance path myself someday. cheers