Monday, August 27, 2007

Lathe Bits

Over the last month, I've been making some tools and mods to my lathe. In the process, I've used a few different types of lathe bits. I first ordered the Taig HSS tool bit which worked really well for aluminum and steel. These are great to get started. However I found out that you do have to touch them up once in a while, especially if you machine some of the harder metals. On one of my trips to the local harbor freight, I found a small 5 piece set of brazed carbide bits in 1/4" size. Figured I couldn't go wrong for $4.99. I was wrong. They suck! Only one of the bits was usable out of the box. The others were brazed on so crooked that the main shank hits the part that's being machined before the cutter! Oh well, live and learn. I do have some extra HSS 1/4" blanks to play with as soon as I get a grinder. There's a nice write up on the Sherline website about grinding HSS lathe bits. I looked around for some indexable bits but they're harder to find in 1/4" size. I saw some on Ebay but was wary of quality. Back to Harbor Freight, I found a nice set of inexable tool bits in 1/4" that actually looked decent. The inserts even have chip breakers. I plopped down my $17.99 and brought them home. I was very pleased with their performance. Worked great on Aluminum and 12L14. This is what one looks like:

They come in a little wooden box with some extra screws and 2 small wrenches. I have to say I'm happy with this purchase. Again, sorry about the picture quality. It'll be a little longer before I get a new camera. Priorities, you know :>)

Getting Cranky

Over the last few days, I've been working on a replacement crank for the crosslide on my Taig. The stock crank is functional but very small. I wanted something more robust with more leverage. I also wanted a spinner handle for smoother cranking. This is what I came up with:

The spinner handle was made out of aluminum, the rest of the assembly is free machining steel (12L14). It took me a few days to make as I was working without drawings, and basically making it up as I went. Really turned out nice and is so more much comfortable to use. I can even tighten up the crosslide gibs a little more as I now have more leverage to turn the crosslide screw. I really want to get working on my first model, but I want to get all my mods done before I do. My next step is a milling column arrangement with the milling adapter which will mimic a 3 in 1 type machine. Also a leadscrew is in the works. Hope to get this done over the next week.

Thursday, August 23, 2007

Tools To Make Tools, To Make Tools, etc.

Continuing on with my tooling efforts, I decided I needed an adapter to hold dies on the tail stock, and an adapter to install my drill chuck on the headstock spindle. Both these accessories are available ready made from Taig for about $27.00 plus shipping. But what fun would that be? I made both adapters for about $6.00 and a few evenings of work. I practiced my facing cuts, turning cuts, drilling, boring and threading. All basic skills needed for model building. Here's the results:

Tailstock die holder on left with die inserted , spindle chuck adapter On right

Threaded end of both adapters

Tailstock die holder without die

On both adapters you can see holes drilled across the bodies. This is to facilitate tightening and removing the adapters. Just insert a tommy bar and turn. The tailstock die holder is made out of a piece of 1-1/2" 6061 aluminum, bored through 3/8" to accomodate a length of stock to thread and with a 10-32 set screw to secure the die. The spindle adapter is made out of one of the pre-threaded blank arbors bought from Taig for $2.60, made from free machining steel. I had to make the die holder first, so I could thread the spindle adapter 3/8"-24 for the chuck to screw on. Both work great. It's a great feeling of accomplishment, and I'm looking forward to new projects in the near future. Please bear with me on the pictures as I'm using a borrowed camera which is older and not as high resolution as I'd like. I didn't take pictures of the making of the adapters because my access to the camera is limited, but hopefully soon I'll buy a new camera so I can take some action shots.

Monday, August 13, 2007

Let There Be Swarf...NOT!

Ever since I decided to get into this hobby, I knew I was going to have to figure out what to do with all the swarf. I'm not talking disposal, I'm talking the avalanche of swarf that accompanies any use of the lathe. In my limited machining time, I have been pelted with it, burnt by it and to be honest I'm not thrilled by it. Clean up can be a bear and swarf gets everywhere! My first step in the war against swarf was placing my Taig inside a shallow plastic storage container I bought for $7.00 at Wally World. That was a big improvement. After cutting some metal, I just use a paint brush to sweep all the shavings off the lathe and base inside the container. When there's a large accumulation, I take the lathe with base out of the container, dump the swarf in the trash and put the lathe back in. However all is not well; turning metal launches chips up around and behind the lathe so the swarf problem is still there to a different extent. My next solution has resolved this and has worked great. Only spent about $10.00 to do it. Here's some pics:

This is the lathe in the container with chip shield

This is a better shot of the chip shield

The shield is made from a piece of 8"x10" Lexan cut in two, attached to a copper angle bracket that's predrilled. The bracket is actually bolted onto my lathe back tool post which is bolted into one of the T-Slots on the headstock. It works great and is very adjustable. Swivels away easily. Chip control is vastly improved and that makes me a happy camper.

Welcome To My Cave

This is the first update since I got done moving. With the kids out of school for the summer and a new home to organize, it's been rough around here. Besides my digital camera finally died. I did start tooling up the Taig. Bought a milling adapter, a few collets, the drilling tailstock, cutting bits, etc. You never get done tooling up! I splurged and bought a set of US made, screw machine length #1-#60 drill bits from Enco. They're so nice I'm scared to use them! Anyway, here's a picture of my new cave:

Once I buy some shelves to put on the right side, I will have some more floor space. It's still very hot here in Las Vegas so I've been messing around in my corner of the garage after work. I get off at 4 A.M. so it's less hot. I got a vise from the local HF and bolted it down in the corner of the desk. It has been nice to have. Helps greatly to hold stock for cutting and grinding. Just need a bandsaw now! The hacksaw got old real quick. I'll be posting quite a bit in the next few days to catch up with all the new stuff and lathe mods which I have started on.

Thursday, June 28, 2007

3D Doodling

I'm presently in the final stages of my move. Jury Duty didn't help either. It's been a long and arduous week. Anyway since my shop is in boxes right now, I decided to reacquaint myself with Rhino 3D to keep my sanity. I have an older version (2.0) which came installed on my used laptop. It works fine for me. I decided to work on a design for an I.C. engine just to challenge my brain. This is what I have so far:

It's a concept only so far although the proportions are close to what I want. As you can see its a 4 cycle engine with a belt driven camshaft. Obviously it's missing a few details still but I have quite a few hours into these drawings. I'm thinking 1/2" bore with 3/4" stroke and 2.5" flywheels. A nice size envelope for a Taig. Hopefully in the near future I can start on some working drawings.

Friday, June 8, 2007

Let there be swarf....

I've been in limbo with my machining endeavors due to an impending move. Budget was temporarily derailed by this. Good news is that I will finally have a garage to play in. I should be moved by the end of the month. Continuing with my lathe buildup and tooling, I received my 4 jaw independent chuck and right hand cutter yesterday. I cleaned the 4 jaw chuck out and reversed the jaws so I could try a few test cuts. I installed the new cutter in the tool post. **CAUTION- The cutter comes with a plastic covering over the the sharpened end to protect it from damage during shipping. Be very careful when removing it; I gripped and pulled the cover off the end with my right hand fingers and promptly cut a nice 1/4 slit on the tip of my index finger. These tools are very sharp!!! Be safe.** I have a 2 foot length of 1/2" hot rolled steel rod laying around so I figured it would be a great test for the lathe. I cut a 3" piece off and chucked it up. I used my dial indicator to get it as true as possible. I set the tool bit cutter edge parallel to the rod and then did some light facing cuts on the end of the rod. I played with speed and feed to get the best results. It took about ten passes to get the facing done (lousy hacksawing technique!). I am new at this so I'm learning as I go. I then proceeded to do some regular turning on the rod. I set the carriage stop rod a safe distance from the chuck. I started with a light cut and was surprised to get some significant chatter. I played with the speed and feed with little improvement. I started wondering about the capability of the lathe until something dawned on me; I forgot to reset the angle of the tool holder after facing the end! It would take a lot of power and rigidity to make any cuts with the side of the cutter! After resetting the tool, swarf started flying!

Yep, that's some swarf there!

I was able to reduce the rod a few thousands with a nice smooth surface. It's going to take some practice to learn how to turn the handles smoothly though. I think the addition of a leadscrew is going to be very beneficial in this respect. Also, I'm going to design some kind of larger handle for the crosslide. There are a few issues I noticed with the lathe operation. The crosslide is noticeably tighter when moved towards the handle. After checking it out I can see that when the handle is turned counterclockwise, the dial assembly is pulled against the bearing block assembly significantly increasing friction between the two. Therefore the handle is harder to turn. When turned clockwise, the opposite occurs, thus the handle turns very freely. Maybe some kind of thrust washer can be used or maybe lapping of the dial/bearing block interface. I'll have to see. I also think that i need to spend a little more time lapping the crosslide to the carriage assembly to smooth it out. I'll be busy over the next few weeks with the move but I'll be definitely be working to resolve all the issues.

Tuesday, May 15, 2007

Speed Control Wired, Lathe Mounted

Got back to work today on the lathe. My drive pulleys came in as expected with the belt.

I am using two headstock pulleys because the shaft on the motor is 5/8". The pulley is not bored all the way through. Because of this the lathe sat too far to the right on the mounting board when the pulleys were aligned back to front. Therefore I decided to rotate the left side motor bracket 180 degrees and move the right hand bracket two inches to the left. The motor overhangs the board on the left about 3" now but the lathe fits perfectly. After i did that I got back to hard wiring everything and fitting it in the box. I added a power switch, a fuse holder and mounted the box on the board. I finally bolted the lathe on the board.

I still haven't got a knob for the speed controller potentiometer but everything works great. I want to add a power light but I'm going to have to look around for something small because the box is kind of crowded. Going to order a 4 jaw chuck this week and some cutting bits so I can start making some chips.

Monday, May 14, 2007

Lathe Drive Install

My Minarik speed controller arrived over the weekend so today I decided to get some work done. First thing was to hook everything up without switches or enclosures just to determine that everything works.

(Please disregard the dates on the photos as my camera's been acting up)

I'm happy to say that everything worked great the first time i plugged it in. I only had a simple schematic to work with but I did work in electronics for many years so that does help. Next, I had to screw down the steel sheeting on the mounting board as the glue I used was not as strong as I thought.

The sheeting is now on there solid although as you can tell by the picture, the sheet is easily marred and scratched. After this, I tackled the motor mounts. Two metal brackets from Home Depot did the trick.

I purposely let the left hand bracket overhang because I'm thinking of installing a goose neck halogen spotlight there. Here's the motor mounted:

I like the way the mounting system came out. The motor pivots on 1/2" bolts which allows for belt tightening. Finally, I started installing the speed controller in a box and gave the motor another test run to see how the mount holds up.

I'm excited about this motor/controller combo. The motor is very smooth running with very minimal vibration. I turned it way down to a crawl and the torque on the shaft was amazing. I couldn't stop it with my hand. UPS will be here today with my drive pulleys and belt so I will be installing those and finally mounting the lathe to the board. I also have to finish hard wiring everything. Stay tuned.....

Tuesday, May 8, 2007

Motor Found!

Well Ebay came through again. I got a great deal on this Leeson 1/4 HP TEFC 2.5 Amp 90VDC motor. It was been used to power a conveyor. The plug on it is not an AC plug. It's some kind of strange DC plug. The motor is a lot bigger than I thought. The output shaft is 5/8" diameter keyed. Took me an hour to wrestle that pulley off. I will be installing the Taig pulley set on it.

This is the controller I ordered from Surplus Center for variable speed control of the motor. These are the specs:
  • Input: 115 or 230 VAC, 50/60 Hz
  • Armature voltage (115 VAC IN): 0-90 VDC
  • Armature voltage (230 VAC IN): 0-180 VDC
  • 5 Amps output, 10 Amps w/heatsink
  • 1/8 Hp to 1 Hp @ 90 VDC
  • 1/4 Hp to 2 Hp @ 180 VDC
  • 1% regulation over 60:1 speed range
  • Size 4-5/16" x 3-19/32" x 1-19/32"

This controller and motor combination should work great. I expect the lathe to have plenty of power for any type of operation I may attempt. As soon as I get everything running, I'll post an update.

Wednesday, May 2, 2007

The Desktop

This is where all the action will be. You can see the Taig Microlathe in it's current state. It's actually not bolted down yet, just sitting there. I purchased the basic kit. All the initial lapping has been done. The mounting board is a 12"x 24" shelf purchased at Lowes. I added a sheet of 22 gauge steel on top for durability. I was going to use the motor in the upper left corner which came out of an old electric scooter. I decided against it however because the power supply would have to be rated at 40 amps which is huge. I have the battery and charger that goes with it but the battery (Seen on upper right corner of desk) weighs a ton and I would have to constantly be recharging it. I'm hunting on Ebay for a suitable motor.

Tuesday, May 1, 2007

The Beginning

This blog will detail my adventures in home machining. As the title of the Blog suggests, all work will be literally done on a desktop. I will be living in an apartment for the foreseeable future so all my equipment will be geared towards the smaller end of the spectrum. To get started, I have selected a Taig Microlathe. In this size range it's pretty hard to beat the bang for the buck. Budget plays a big part in my plans so I will attempt to make some mods to the lathe as well as build some tooling to keep costs down. My plan is to build some projects from existing plans and to try my hand at designing my own. Steam, I.C., and sterling type engines are all fair game. Stay tuned for more as I get tooled up and ready to go.