Was a beautiful afternoon here and so wandered out to the man cave in one of those "wanna make something" moods. There's a particular pancake chassis gear puller that I'm having trouble buying so I figured I'd make one. Come on.... I mean, how hard can it be?
I had long ago saved a picture of one that some guy had made from a common nut. Grabbed a 3/8" nut and drilled the thread out - well most of it anyway. I carefully cut away one side of the nut to leave a small opening for the arm shaft. Hmmm, to be honest I cut away a fraz too much but that's beside the point.
Pleased with my level of genius at this point, I set about making a small grind in each lower shoulder of the nut to enable it to clear the raised edges of an AFX gear plate. So far so good. Load the nut up in vice and use a small flat file to flatten the "round" lower portion of the inner circle. In theory this would increase the pulling surface of the jaws. After a couple of test fits and a little more filing it was slipping nicely under the gear.
I have a threaded 1mm drift (correct term?) that I made for one of my other pullers and figured I could also use it on this one. Centred the nut up under the appropriate drill bit in the drill press and drill the hole. No problem-o. At this point I would reach for my thread tapping set but I don't actually own one. That's ok, rather than going and buying one I'll lightly taper the end of a spare matching bolt, grind a spanner grip on the sides and use that! Have done it before so why shouldn't it work for this.......
I begin cutting the thread and it's going nicely, actually ejecting little curled pig tails of steel as it cuts. Half way through I back it out to clear the freshly cut and cutting threads. Start cutting again and the bolt snaps. I'm sure I was no more that 1 turn from completion. Maybe I should have used some WD40 as a cutting lube. That's ok, grab an ezi-out and drill a small hole through the bolt portion left in the nut. Snap!! Oh well, there goes the ezi-out! I eye balled my other ezi-outs but decided to cut my losses.........
When the frustration subsides I'll give it another go on another nut and may have to look into investing in some thread cutting tools. The pics below show the target item and what is now residing in the Fail Box.
*** Anyone care to share an actual success story of DIY slot tools, with photos if possible. There's gotta be some great one's out there.
Cutting oil is cheap and WD40 is not an equivalent. WD40 is really never a good choice for anything other than what it's named for... Water Deterrent, aka keeping rust off tools.
I saved the eye dropper and bottle from our boy's infant vitamins for it. Makes for much less messy work having the dropper AND only a small bottle to spill... Just be sure to label it as such. That and a cheap tap and die set from Harbor Fright has worked wonders. The cutting oil is the key to keeping things from snapping and getting a longer life out of cheap-*** tools.
I found a use for those longer 0-80 screws i bought for the 4gear rivet replacement project. I threaded one throught some thin flat plastic and molded the plastic piece to one of my hobby vise jaws (this vise has a swivel head so it can go vertical). It slips on instead of the rubber cushion, and serves as a cheap mans gear/wheel press. For popping out motor pinions, i use a socket to hold the motor as it drops.
One of my To-Do projects is a DIY CNC machine, as i have plenty dremel tools laying around.
Jisp - G'Day Mate, and that is a great idea for a puller! I am going to have to try my hand at making one.
Rich - Great tools, i especially like the motor balancer. What did you salvage the level from?
After watching a youtube video on someone selling their slot car test setup for 1/32 cars, I ordered a digital tachometer direct from China. About $17 plus 1-cent for shipping. (funny). I plan to mount it to a plastic box along with a Model Motoring starting track (you can find these on ebay for very cheap) and ending up with a dynometer. If you don't already have one, dx.com also sells a super cheap kitchen scale for about $9 that would help in weighing your cars, etc.
That is impressive ingenuity, on a level I'm proud to say I admire! Great use of available materials!
I bought a yellow handled one off the 'bay last year. Kinda like the RTHO one, but yellow instead of red. The RTHO one, no doubt it's a custom made tool.
The one I got, I'm almost convinced it's merely a small watch gear puller that has been modified to shave the bottom section super thin. As the bottom is kinda rough, like it's been ground down to thin it out. Perhaps the average joe could do the same by finding a small watch gear puller and shave the bottom to be thin...
I actually have the one I got, I no longer need Jisp, I'd gladly send it to you. I don't mess with Tjets anymore, and my Axion Chassis in development, doesn't require it's use. I was about to reply to your email, telling you I'd send it your way. Just give me the word...
Sweet tools Rich. You obviously know your way around a machine shop. Any further info on the gear press in the centre photo? Is the pin on the right for mounting other tools on and what chassis does it work with?
Z, how many of those 0-80 screws do you have? If you want to unload some I'll buy them if you can ship to Australia. Don't feel obliged though, it's just a thought.
S8, slick work on the driver station. If/when I ever make a permanent layout I'll be looking into DIY options.
So, regarding that rather sad looking nut in my original post........ typically male, I don't like to go down without a fight. I hit the man cave earlier to begin version2. I took a little more time in order to set up a more accurate way to make the initial cut across the bottom of the nut. Scored a point there with a much better result than v1.
W99, I decided to take your advice and abandon my man cave (cave man?) ways with regard to tapping holes. I dropped by a hardware store and grabbed a small set of thread taps and some cutting fluid. The thread taps are a long overdue addition to my tools. Will get some photos up when I get a chance.
*** Anyone else with some DIY slot tools to share??
Jisp, i have used a total of 3 of the longer screws, so i have about 97 laying around waiting on projects. Do you know how much a letter to Oz is from U.S. ? I could try dropping a few in an envelope to ya.
The pin on the right on my gear press is a slip fit in the frame and is used to center the pinion gear. There is a dimple in the face of the screw to center the motor shaft. As the pinion gets pushed on the end of the motor shaft just pushes the pin out of the way. The press was made for 1/24th motors, but it works just as well with 1/32nd motors.
If you are going to make your own tools starting with nuts and bolts you might be better off getting high quality hardware from an industrial supply house. Hardware from a discount store is likely to be of poor quality.
Rich, I like the slip pin idea and will file that one away. I hear what you are saying about using quality parts to begin with. I've just been messing around with parts I had lying around. The steel for the nut is what I'd call decent quality but the bolt is just a cheapie.
Well, I had a second go at it earlier and have a better result this time around. All I need to do to finish it is file the lower inner curved shoulders flat for good contact with the gear. Not surprisingly the thread tapping tool made the job quick and easy ( W99). Groan..... last day of holidays today. Back to the real world tomorrow....