Story:
I bought a bunch of tools at an auction lately and some of the concrete tools had old hard concrete plastered all over them. Obviously, they didn't take care of them very well. I also bought a 4' bull float with five 6' extensions and that one was pretty bad as well.
After building a little frame out of 2x4s and placing some plastic in the middle, I put the tools in the trough and poured 6 liters of white vinegar in it. All I had to do is let it soak for 10 minutes and scrub off the old concrete with a paint scraper and a wire brush.
The acidity of the vinegar dissolved the concrete to the point where it came off really easily. Best trick ever!
Videos:
Pictures:
Tools:
Air nailer
Compressor
Knife
Paint scraper
Wire brush
Materials:
Two 2x4s
12" x 60" plastic
6 liters of white vinegar
Cost:
$5
Time:
1hr
Conclusion:
It worked really well and the tools are back to how they should be
I bought my wife an overhead projector because she's always wanted one and decided I was going to buy a spare bulb in case the current one broke. Luckily I found one on Amazon for $19.95 (US) with free shipping to Canada.
About an hour after purchasing and feeling great about it I got an invoice for $86 (CAD) and I was like "what???". Immediately I canceled the order thinking it would all be great and dandy, just to get an email that evening saying my order ha shipped. Again, I was like "what???"
I contacted the seller and they said to simply return it and they'd refund it. About a week later I got my package (it was about 3" by 3" by 3" and weighed less than 200g). I didn't even open the package but did a "return to sender".
Today, I got a notice that they reimbursed me, except, they only reimbursed me for $19.95.
After calling the credit card company, they said they can't dispute shipping charges and amazon said that I agreed to pay the $45 (US) WHICH I DID NOT.
Here's a screen shot of what I ordered as proof. Now it's back to amazon to see what they can do. What a crock!!!
Difficulty Level (Easy, Medium, Hard, Insane):
Hard
Process:
I was working on my SSR Heatsinks for my kiln project when all of a sudden I heard this horrible noise. I turned off the mill, took off the mill head covers and immediately saw that one of the tufnol gears had broken off 3 teeth.
I spent the next few minutes poking around and thinking of all my options and decided that I'd have to take it apart first to have a good look at it.
After taking it apart and looking at the design of the mill head gears I realized that I MIGHT be able to press off the tufnol gear, make a new one out of nylon and press the new one on.
I sent a message to my Emco Larger Lathe Yahoo Group to see if anyone has run into this issue before and there actually were several individuals who either made a new gear, had a machine shop make one for them or bought one and pressed it on themselves.
One of the gentlemen even wrote his own Documentation when he had to go through this same exercise which, after readng, I was quite a bit more heartened than before and decided I was going to tackle this project. It was certainly not what I was expecting to do but at least I saw some hope that I'd be able to fix it myself.
After cleaning everything really well I re-assessed the situation and noticed that there was a LOT of play in the middle gear which ran on needle roller bearings.
I looked at the parts list document for my lathe and determined that I need two HK1210 bearings. Luckily, Motion Canada had them in their Toronto warehouse and they were under $4 bucks each and I got them to Moncton in only 3 days.
Once I received the bearings, I removed the old ones, which I ended up having to completely obliterate and even use a dremel tool with a grinding stone to grind through the outer race because they were pressed in so hard and the outer races were hardened steel.
The last thing I had to do was to press the old tufnol gear off the shaft and take the finished nylon gear and press it onto the shaft (I used some 5-min epoxy).
Originally, I was shooting for about 10-15 thousands of interference so I could press the nylon gear onto the serrated iron shaft, but after I pressed the old tufnol gear off the shaft I realized that I ended up only having about 1-2 thousands of intereference. Because of that, I decided to drill a 3/16" hole through the nylon gear and part of the wall of the iron shaft and install a roll pin in case the 2 thou interference wasn't quite enough to lock the nylon gear in place.
In retrospect, since the tufnol gear was shot anyways I should have pressed the broken gear off the shaft and taken proper measurements; that could have avoided having to use a roll pin.
Once the new gear was pressed onto the shaft, I put the gears back in the gear box and filled it up with Motomaster Moly Extreme Pressure NLCI #2 Grease and was finally able to continue making my two DIY SSR Heat Sinks for my Electric Kiln.
Videos:
Pictures:
The top portion of the mill head with motor
The first gear (16/24 teeth)
The cleaned up gear with the key
The bottom portion of the mill head with the moly grease
Pulling off the broken second gear (24/16 teeth)
The cleaned up gear with the 3 broken tufnol teeth
Another view
Gear specs with the broken tooth area circled
The third gear (35/43 teeth)
The third gear assembly
The cleaned empty gear box
The 940 RPM setting (24 > 16 > 43)
The 420 RPM setting (16 > 24 v 16 > 43)
The 770 RPM setting (16 > 24 > 35)
The 1740 RPM setting (24 > 16 ^ 24 > 35)
Calculating the different gear ratios
The raw stock of 2.500" nylon
Getting the outside turned to size
The replacement gear specs
Test fitting the nylon gear blank on the shaft
The outside turned to finished size
Using a boring bar to cut a recess into the gear
Another view
The dividing head set up and ready to cut gears
Cutting the gear
The finished gear
Installing the fixed gear
Filling the mill head with grease
Stock picture of the moly grease I used for the gear box
The finished mill head
Tools:
Metal lathe & accessories Metal band saw
Screwdrivers
Wrench
Hammer
Cordless drill
Crow bar
Adjustable wrench
Diamond sharpening saw
Angle grinder 20-ton shop press
Parts washer
Form tool Fly cutter Dividing head
Dremel
Chisels
Awl
Snap ring pliers
Materials:
Motomaster Moly Extreme Pressure Grease
Rags
3" of 2.500" nylon
5-min 2-component epoxy
3/16" roll pin
Two HK1210 drawn cup needle roller bearings
Cost:
$15
Time:
10-15 hours
Savings:
$100 at least
Conclusion:
It works, but the gear is definitely a bit louder than it was before. I'm assuming that the gear will wear in over the next few hours of using it and even if it didn't, I'd rather have a little louder mill than no mill!
Difficulty Level (Easy, Medium, Hard, Insane):
Medium
Story:
The last thing I knew I'd eventually have to do after Converting my Manual Gare Kiln to PID Controller Programmable Kiln was to install two SSR heat sinks, one for each SSR. I was contemplating buying some online which I could have done for about $30-$40 each, but since I already had a foundry and a mill I decided to cast my own blanks and then use my mill to cut the fins into the block of aluminum.
Little did I know that I was going to learn MANY, MANY, PAINFUL lessons during the process.
Lesson #1: Sharpen your slotting saw
Lesson #2: Don't use staggered tooth slotting saws on an under powered mill
Lesson #3: If you have to do #2, take light cuts
Lesson #4: Take light cuts
Lesson #5: Take light cuts!
Lesson #6: When the milling saw starts cutting with harmonics, FOR HEAVEN'S SAKE, TAKE LIGHT CUTS
Lesson #7: Fixing your lathe/mill with your lathe/mill is amazing
Videos:
Pictures:
This is the heat sink I'm aiming for
Currently I have the SSR modules mounted on a 1/4" piece of aluminum
The kiln with one of the aluminum pieces visible
A block cut from a regular 2x4
My son helping me (cast his McDonald's toy)
The mold
Another attempt (the first one didn't turn out)
Sifting some green sand over the wood patterns
The completed mold ready for pouring
Cleaning up the rough surface of the cast
One side done
Another view
The measurements I calculated using AutoCAD
About half-way done with the slotting saw
Another view
Another view
Another view
The finished heat sinks. The right one got mangled pretty good (see lessons #1-6 above)
