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How sextant works.. Note the mirror moves . Next is plumb to horizon Dave

FYI Background I had check class 45 cast iron and would not fit in Rockwell tester. Rutland had a unit for none destruction testing I purchased and very simple . A 3/16 ball from ball bearings. And a clear tube . It work but easy to lose the small ball so I up size so easier to find the ball. Then used a paint stick good and bad marks . Now my crew could check the hardness too. They set wheel on floor and drop ball. In time a rug around the wheel stop ball from hiding . The pickup ball and check next wheel. We did not check every wheel just in in each batch. Then when looking materials it came handy too. Dave FYI I still have the test disk from Rockwell hardness test I think last for ever it never leaves a mark

I look at building a pocket size Sextant Most are 3" [75mm] to 4" [100mm] I decided to build a little bigger for easy it about 5?" [138mm] x 5" [125mm] . Using a off shelf protractor. This to save time over making a protractor. I found a WEN PROTRACTOR easy to repaint the numbers. The mirror doubles the number. Basically if The mirror moves 90° it would only read 45°. So need to renumbered to 90°. ? WEN protractor and close-up ? ? Dave

I had to make a new worm gear for an N gauge loco, 5mm dia 1mm pitch in brass, the only issue was it needed a 0.8mm (32 thou) hole for the motor shaft. the first one i made I threaded the outside of some 5mm brass rod, then tried to drill using a standard 0.8mm drill bit. now centering the drill is the main issue, and though it looked good, when mounted on the motor shaft and taken to full speed, there was vibration. so i had another go today, this time using a 0.8mm carbide PCB drill, these have a 3mm shank and a drill section about 1/2" long, being very careful when starting the drill, barely touching and just very gently started the drill- now these drills will break if you breath on them wrong, but i managed to get the drill centred with no apparent wobble, then pushing my luck I drilled to a depth of about 10mm (3/8") this went on the motor nicely, but was a little loose, so I tried again with a 0.7mm PCB drill and that one was too tight (maybe a press fit, i am not sure. needless to say, the n gauge loco is now running smoothly. I do love the precision i can get from my unimat 3. does anyone else have any techniques for drilling similar small bore centre holes? Peter

Here a list files Charts & Tables for Machinist's. I have found to be very handy doing work . I hope you post your favorite charts & talbes. I uploaded to a different site so I do not fill up this site. I put mine in a 3-Binder in tool chest. The tap and drill chart I have extra large on my wall. Very handy /g/minilathe/files/5%29%20Charts%20&%20Tables%20for%20machine%20work Dave

A recent thread had a link to the wonderful clickspring YouTube clockmaking videos, and I was intrigued to see him use ‘taper pins’ to be able to accurately realign two plates( or, presumably, other items. Seems like a very smart solution. Does anyone use these? Do you drill the holes (with a taper drill), or use a reamer? And any other equally smart solutions to achieve the same thing? (Sorry, not specifically Unimat related - but at least it’s metalwork !)

Happy New Year all ! I’m after advice from horologists, or just those used to making tiny things! I’m fitting a small quartz clock movement into a small, broken clock. The face is nice, but the available hands that fit the quartz movement aren’t, so I wanted to use the original metal hands. The new shafts are bigger though - 1.5mm > 2mm (minute hand), 2.6mm > 3.5mm (hour hand). I tried to open the minute hand hole up using a spike / bradawl, tapping slowly and very gently. Of course eventually I split it. What isn’t visible from the photo is a slight bush or flange effect around the back of the holes, presumably the holes have been pressed out and this helps the hand stay straight and true on the shaft. That’s why I didn’t just try to drill out the holes. Anyway, any advice on how to make new hands (and from what material)? Even gripping them for filing etc. would seem very tricky… Or is it possible to rescue the old ones? The minute hand just slops around on the new shaft now.

I am interested in either purchasing or making a set of adjustable handwheels for a DB 200 lathe. in searching the forum there were some posts mentioning that there were some being made and sold in the past. It does not seem like anyone is making or selling them presently. A dial indicator is very accurate and have used them. At this point I am not interested in installing and using a DRO, maybe in the future. I prefer adjustable dials because they are common and convenient. All of the equipment in my shop have dials that use a set screw to move and lock manually. There is one exception, a small bench mill that has the friction type. A search through the Files section did not yield much information as to how to make them. An article in ME Workshop (Feb.2006) has plans for a set to use on a Unimat 3. They are kind of large 1/3/4" in diameter but may work on a DB. Just curious if anyone has made and used them. Also, any information or plans to make a set would be greatly appreciated. Thank You

Today I installed my digital read out on my Unimat Z axis which is the longitudinal travel. It is nice to be able to set zero at any point along the travel. It took some time to make special brackets for mounting but it paid off in the long run. Now I will need to make some resettable hand wheels to suit. I have done all the machining on the little Unimat as it is the only piece of equipment I have at this time. The more tooling I build on the Unimat the better equipped I get. I am building my “Unimat Shop” one piece at a time. Proficiency and speed builds as I go. Dick -- http://www.homemadetools.net/forum/ OFF-SET-tailstock-center-65965#post105972 http://www.homemadetools.net/forum/s...995#post112113 SMALL TURRET TOOL POST PLANS http://www.homemadetools.net/forum/l...994#post112111 LARGE TURRET TOOL POST PLANS http://www.homemadetools.net/forum/m...383#post110340 MINI-LATHE CARRIAGE LOCK PLANS http://www.homemadetools.net/forum/s...191#post106483 SMALL QC TOOL POST PLANS http://www.homemadetools.net/forum/q...849#post119345 QUICK CHANGE LATHE TURRET http://www.homemadetools.net/forum/m...949#post119893 MINI LATHE COMPOUND PIVOT MODIFICATION

I bought this Unimat 3 quill handle and it has this gear on it. Is this a Unimat item for a quill feed drive, or possibly something someone made?