Member postings for old mart

Glad you got things running well. I have an R8 er25 collet holder that has problems with similar runout which would probably need internal grinding to rectify. The other two that we have are fine. You also have to be cautious with cheap collets, they can be poor if you are unlucky. I usually buy the sizes to match milling cutters from APT, they have three grades that you can choose from, and good prices.

I just googled "wave washer" and got hundreds of answers instantly.

The runout is not described properly, is it radial or something else? Assuming that the register is running perfectly radially and the face of the backplate has been skimmed, and the collet plate fits it snugly, where is the runout measured from? The OD of the plate or the bore? With a test bar held in a collet? Has more than one collet been tried? Is the collet bore concentric with the register in the back of the plate? With a test bar in a collet, if the only error is radial, then the error will be the same right up against the collet as it is 3" further out.

There is nothing wrong with having an undersize register, the bolts holding the collet plate and friction will never allow unwanted movement. In the real world, you have to make these things work, not just say it is not allowed.

An improved handle like yours is among the many "to do" modifications I have in the pipeline. Alan has already made a short radius handle for the Bison vises which will miss the Y axis handle on the round column mill when being turned. We now have three variations of handles for the 100mm Bison vises which get used most often. At the moment, the 5" ARC vise is being used exclusively on the round column to hold the new cross slide for the Atlas lathe which should be finished within the next 2 weeks.

They do look like the old style boring bar bits. And there is a toolholder for turning laying about in the workshop which holds something similar.

Edited By old mart on 02/06/2023 19:05:33

I would find a very fine file which was wider than the banjo diameter and carefully smooth off the faces. Check that the faces are kept parallel. I would also anneal the sealing washers before installing, as I don't entirely trust them to be in the soft state even when new.

I know what is better with the redesign, you can spin the handle much faster. We have a 5" ARC vise and I find the handle fine for about one turn, but not so good if moving the jaw any distance.

That is similar to how I use one of those gauges. If the hole diameter is important, I will take up to three measurements, and hopefully they will be close to identical. I would not expect to be closer than 0.005", but that isgood enough for government work.

David George's post number 3 has everything needed. I had to use the same method even while having the infinitely superior taper turning attachment on the Smart & Brown model A. Morse tapers require second of arc precision and are all different for some reason.

Edited By old mart on 30/05/2023 16:58:40

As I say, again and again, if you have a choice between MT3 and R8, always choose the R8. Morse taper was designed for drills and works very well with them, not mills. Ignor the Morse taper fans, they are wrong, these stuck MT threads are a perennial feature of the forum. Just check out the number of stuck R8 threads.

Edited By old mart on 30/05/2023 16:50:13

You would need to see whether the motor can run in delta as most single phase input VFD's are not for star wound motors. The VFD must be connected directly to the motor as already mentioned, and running more than one motor from the VFD has been done, but not recommended. A lot of ancillary motors on Bridgeports are 115V, so that would require more research.

We have lots at the museum, many donated, and I find that however many sizes you have, it's always the size you don't have that you want to use.

Oilite sintered bushes can be bored without sealing the pores, but reaming is not recommended. The bushes are freely available from bearing stockists or ebay. I scrapped a much newer Black and Decker D720 two speed after I happened to look inside the handle. The wiring insulation was disintegrating, not a good thing for a metal bodied drill made before double insulation.

I have bought big names at a fraction of their list prices on ebay, and also Chinese ones which are very good for hobby use. As already mentioned, APT are a great firm and they are competitive and fast delivering, their tools start from 16mm square shanks upwards. Some of the inserts they sell are aimed at hobbyists and available in smaller quantities than the normal boxes of ten. The advantage of this is that you can try out a variety and not be stuck with 9 unsuitable ones if a bad choice is made.APT also sell threading inserts singly which is handy if you want several types. ARC is another good bet and Cutwel for special tools which are hard to get

Edited By old mart on 25/05/2023 20:59:48

One of the chucks we have at the museum had poorly fitting key, so I knocked out the crossbar and bored the end to take a closer fitting pivot which keeps the bevel gears in mesh much better.

I did increase the thread size in the dial tp 3/8 UNF to make it easier to incorporate and will be using a pair of shielded ball races for axial control. The ball races have 0.005" axial displacement from flat, so I found a 0.010" thick shim which was modified to sit between the outer races. The inner size of the ball races is 9.95mm which is perfect with the 3/8" threaded end. I worked out why the leadscrew threads are short both ends in the Atlas 12 x 24, the leadscrew nut runs off the end of the leadscrew before the power crossfeed crashes in either direction at the end of its travel. I will be having the complete travel and doing away with the power cross slide, it won't be missed.

The Myford resettable dial arrived today and is very good. I might take it to bits and put a bigger thread in it if needed, but the 1/4 BSF will probably be ok. The extended cross slide has to wait for a 60 degree dovetail cutter, I could only partially mill with the 55 degree one that I already have. That is enough to fit the slide in place and decide further plans. Mike made the gib today out of 1/8" brass, difficult to hold when milling the edges at 30 degrees, so it sits in place nicely. There will be 6 gib screws instead of the original 4.

Is there a capacitor attached to the side of the motor? They are a common source of not self starting when they have failed. The other suspect is the centrifugal starter switch used on many single phase motors. The motor would have to be dismantled to see the switch. Thermal safety switches/cutouts are also commonly fitted, you may well have two faults at the same time. Spare parts should be easy to get hold of by googling the motor name.

Edited By old mart on 21/05/2023 19:06:57

Edited By old mart on 21/05/2023 19:09:54

If you have it wired in delta, then the resistance values between any two of the three should match fairly well. The fourth wire, (neutral), would not be connected to anything. If it was still in star the fourth connection, (neutral), and any other would read half the resistance of the reading between any two of the three. Your sketch looks like delta to me.

Perhaps one of those cheap USB microscopes and you could have a close look at the thread angles on the computer screen.