2020 POTD Thread Archive

[silverhawk]

Don't you think you'll distort the stock by supporting the workpiece between the clamps, rather than under the clamps?
My recommendation would be to sink the counterbores so the 9 SHCSs are below the surface on the 3 extender bars. Secure the extenders to the table, then take a clean-up cut (just has to be 3.25+wide for your workpiece) to make the 3 bars as coplanar as your machine will generate.

Yes. One may think that iron 1" thick doesn't move 6" away from a stationary point - but it does. That's when I use my little "machinists" jacks. And, I can turn the clamps slightly to angle them on top of the 1-2-3 blocks. I knew it would have some spring in it, but I didn't realize how much until that first cut - it was vibrating under a fly cutter about 1/16". I'd have never believed it without seeing it, frankly.

The last picture of one of the clamps holding it was before any cuts were made and adjustments made.

 

[Tim9]

No radius grinding, I'll let the drum do it for me. I am very patient when it comes to not spending money.
I actually used to reline truck brake shoes for a very well known and now out of business company in Massachusetts. That was the late 80's.

Radius grinding was one of those things which we’re supposed to be banned back in the 80’s due to asbestos. And, yes brake shoes still had asbestos well into the mid 90’s if my memory serves me. I remember this because my first job was as a 16 y/o working at an auto parts store. And yeah, they sent me back there more than once to arch the shoes. Just hoping I don’t get asbestosis. Nasty crap.

 

[Superburban]

Radius grinding was one of those things which we’re supposed to be banned back in the 80’s due to asbestos. And, yes brake shoes still had asbestos well into the mid 90’s if my memory serves me. I remember this because my first job was as a 16 y/o working at an auto parts store. And yeah, they sent me back there more than once to arch the shoes. Just hoping I don’t get asbestosis. Nasty crap.

Interesting, I thought it was that brake shoes got better in design, that the radius grinding was not so critical. I do remember a shop that did Big truck stuff, doing the grinding in the 70's, but they also had approximately 1/2" linings. That was the only time I saw shoes being matched to the drum. Thats back when we thought split rims were also a great hing.

 

[devils4ever]

I just finished my drip tray for my keezer machined out of 6061 Aluminum. I used FreeCAD and LinuxCNC to mill all the slots and perimeter of the top piece and the pocket in the base piece which would have been very tedious manually. It came out great except for a slight snafu near the end of the slot cutting.

I was spraying WD-40 on the 1/4" end mill near the beginning of the slot cutting, but decided to stop after about 40-50% was complete. When I only had a few slots left, I noticed the cutter was having issues. See photo. Live and learn. It was running for quite a while and I guess was getting hot. I finished with a HSS 1/4" end mill without issue. I guess I should have kept spraying WD-40? Let the end mill cool after 30-40 minutes?

 

[middle.road]

Then there are those days when nothing comes together in the shop. The stars and moon are out of alignment.
I have an engine hoist we picked up an a estate sale last fall. Another one of my 'it was well-loved' purchases.
Planned to use it to toss the vise on the mill and chucks into the lathe.
Decided yesterday to put it to use tossing around the granite slabs.
Cylinder wasn't functioning when I bought it, but I had checked the oil and there wasn't any in it so I figured - no problem.
I torn down the valve, cleaned it up, re-did the linkage, sanded off the corrosion from the extended 6" and filled it up with a quart or so of fluid.
Put it back on the hoist and started pumping my heart out. It finally took, not real well but it took.
Ran it all the way up and then noticed something odd.

Then I thought to myself (yeah, I know - dangerous) that I'd take a hunk of 2" tubing and just set the boom in a fixed position and hang the HF electric hoist that I got last fall at another sale.
Got the electric hoist after the engine hoist and I was planning on mounting it above the mill and lathe for said tasks instead of the engine hoist.
Got out the electric, mounted a hunk of chain to it and tossed it on the boom, which still had the hydraulic cylinder mounted.
Hung a bucket of water on it and started running it. About 18" had played out when the bucket dropped a few inches.
I figured maybe the cable was unspooled so I re-did that and went back to hoisting the bucket of h2o.
Nope. Something is wrong in the gearbox. Bucket kept dropping a few inches every 18-24" of travel. *SIGH*

All that time and effort yesterday and naught results...
I guess I'm going to see if HF has one of these in stock:

Harbor Freight Tools – Quality Tools at Discount Prices Since 1977

Harbor Freight buys their top quality tools from the same factories that supply our competitors. We cut out the middleman and pass the savings to you!

www.harborfreight.com

 

[BGHansen]

Then there are those days when nothing comes together in the shop. The stars and moon are out of alignment.
I have an engine hoist we picked up an a estate sale last fall. Another one of my 'it was well-loved' purchases.
Planned to use it to toss the vise on the mill and chucks into the lathe.
Decided yesterday to put it to use tossing around the granite slabs.
Cylinder wasn't functioning when I bought it, but I had checked the oil and there wasn't any in it so I figured - no problem.
I torn down the valve, cleaned it up, re-did the linkage, sanded off the corrosion from the extended 6" and filled it up with a quart or so of fluid.
Put it back on the hoist and started pumping my heart out. It finally took, not real well but it took.
Ran it all the way up and then noticed something odd.
View attachment 329025
Then I thought to myself (yeah, I know - dangerous) that I'd take a hunk of 2" tubing and just set the boom in a fixed position and hang the HF electric hoist that I got last fall at another sale.
Got the electric hoist after the engine hoist and I was planning on mounting it above the mill and lathe for said tasks instead of the engine hoist.
Got out the electric, mounted a hunk of chain to it and tossed it on the boom, which still had the hydraulic cylinder mounted.
Hung a bucket of water on it and started running it. About 18" had played out when the bucket dropped a few inches.
I figured maybe the cable was unspooled so I re-did that and went back to hoisting the bucket of h2o.
Nope. Something is wrong in the gearbox. Bucket kept dropping a few inches every 18-24" of travel. *SIGH*
View attachment 329027
All that time and effort yesterday and naught results...
I guess I'm going to see if HF has one of these in stock:

Harbor Freight Tools – Quality Tools at Discount Prices Since 1977

Harbor Freight buys their top quality tools from the same factories that supply our competitors. We cut out the middleman and pass the savings to you!

www.harborfreight.com

Had a problem with mine a while back. Was trying to move my Clausing lathe, get it 2" off the ground and quick push it about 6" before it was back on the ground. Probably the seals on my cylinder. Shopped for a seal kit which was around $35. New double-acting pump cylinder, $50, single-action for $45. Wish I'd have known there was an air-over-hydraulics option.

Bruce

 

[whitmore]

Do you remember in the very early days when TV was heralded as the great educator?
Instead its become a banal opiate for the masses.

I still recall a couple of shows, 'Industry on Parade', and 'The Big Picture' that were
basically industrial training films and military ones. I fondly recall a plunge-EDM demonstration
where a grate was perforated with an array of hexagonal holes, cut in a minute or so of sizzling under distilled water.

As an eight-year-old, that was worth getting up early (7 am?) to see.

 

[mmcmdl]

Heading into work on my day off . Major progress was made in the garage these past 2 days ! Anyone on board looking to buy a machine shop ?

 

[francist]

Well I’m afraid this isn’t exactly a scintillating project but I haven’t spent much personal time in the shop lately. My industry was in the “first wave” of re-opening after COVID shutdown so most of my energy was coming up with engineering controls and product sourcing for work. Amazing how much juice that type of thing can suck out of a person!

But, back to the job at hand, I have one of the small commonly-available 10-ton hydraulic presses — a bench model much like this one:



I don’t use it terribly much, maybe half a dozen times a year if that, so like most of my other equipment I need to have it stow out of the way when not in use. So I scooped a second-hand machine stand off our used marketplace here and channeled it some to bring the depth down to about 12”.

Then I put some wheels on the legs — these are the cheapie solid rubber things you get for two dollars and change at the hardware store. I don’t need this thing to steer, just to roll in and out from the wall in a straight line, and not for any great distance either. I mount the wheels sideways onto the legs so I can keep the frame as open as possible at floor level.



After that I snipped off about 4” from each end of the base pieces on the press itself and bolted it down to the top of my wheelie stand. The most awkward part of this whole affair seems to be the hydraulic hose which, no matter where you try to put it, seems to be always straining to be somewhere else. The angled side mount appears to work the best for me so that’s what I did.

So far it does what I want and tucks cleanly out of the way when it needs to. I may make it an inch or two higher but for now I’ll try it the way it is. That would also be an excuse to redo the two MDF strips which I ham-fistedly counterbored way too close to the edges. As always, thanks for looking!



-frank

 

[Tim9]

Interesting, I thought it was that brake shoes got better in design, that the radius grinding was not so critical. I do remember a shop that did Big truck stuff, doing the grinding in the 70's, but they also had approximately 1/2" linings. That was the only time I saw shoes being matched to the drum. Thats back when we thought split rims were also a great hing.

The higher quality shoes like a premium Wagner brand product probably did away with asbestos earlier, but in New Orleans we had a local rebuilder called Automotive Clutch & Brake. Almost every auto parts store back then was getting the local brand and selling them as the store brand rebuilt brake shoes. They definitely had asbestos linings. In fact...I was 16 years old when I first started working there and that would have been 1976. So yeah, I arched those shoes back then. It only happened when one of the customers was an old timer. Younger customers could care less about arching the shoes.
Anyway, when you’re a young teenager you think you’re invincible. When you hit 50.... you regret all that crap you put your body through . We all pay for our sins.

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