Member postings for old mart

If you are still unsure as to which system to favour, my vote would be for er, and I use both. If you have a lathe, then the same size er can be used on both machines if you get a collet plate which could also be used on a rotary table.

Welcome, Steven, when you get the lathe into the basement, remember to leave space for the mill that will follow shortly after you get used to turning and find that it isn't enough.

Hi, Jonathon, try putting "albums" in the keyword box at the top of the page, or "photos", there will be some useful advise. For adding a link, you can go to the site and right click on the address and "cut". Then paste to the icon marked "link" above.

Edited By old mart on 15/08/2021 16:47:39

If you have a large lump of hard flux, grinding it down using a mortar and pestle will make it easier to make back into paste with water.

You can look up the specifications for steel and aluminium on line and amongst the info should be the machining qualities. Aluminium should be cut with a little lubrication as if turned dry it can stick to the tool edge.

As Pete Rimmer says, it is the parallel spacing that matters, the radial aspect could have been taken care of simply with a scratch made with dividers at two radii.

There was a time when every company which ran Bridgeports used the screwed shank tooling, I have a box of about 1000 blunt cutters left over when I weeded out the sharper ones for the museum. The posilock type of collets are still available new, they are the type that the Osborn Titanic II uses.

Chris, the top picture shows the folding links which keep the upper and lower parts of an undercarriage lined up with each other. I have seen this applied sucessfully to a round column drill mill.

Terry, you will get better results if you shim the mill where it bolts to the stand to get the bed horizontal. If you don't have a reasonable level, a ball bearing sitting on the bed should not move.

**LINK**

Edited By old mart on 14/08/2021 19:15:02

Edited By old mart on 14/08/2021 19:15:30

One way of keeping the vertical movement is a version of the aircraft suspension, using a pair of folding links with close fitting bearings. They are normally fitted at the back of the column.

I remember how deglazing brake drums in the sink used to leave little brown spots stuck all over the stainless steel.

Your tilt measuring device is not sensitive enough. I was going to suggest that you match the tilt of the line to that of the table, but a tenth of a degree would be on the coarse side.

Assuming 4mm at 6 metres and reducing that to whatever your column to spindle distance is would give an approximate movement of the spindle sideways. Say the column to spindle centre distance was 333mm, then the angle moved would be 0.0382 degrees, and the spindle would move 0.222mm. I use the reflection back to the end of the laser which would double the effective distance.

It would be nice to find a laser with a smaller diameter beam, mine is similar to yours. Estimating the centre of the beam should give better results. Make sure the lens of the laser is clean.

Your dial gauge should be 90 degrees further around the quill, either direction, so that movement in line with the X axis is measured.

Edited By old mart on 13/08/2021 20:09:23

I use both, but using the threaded milling cutters has one disadvantage, most are HSS. I do have a few threaded shank cutters with inlaid carbide cutting edges. I believe that a thread on the shank of a solid carbide cutter would not be strong enough to be viable. The er system can hold both HSS and solid carbide.

Clarkson, Acramil and Osborn are three makers which can hold the threaded cutters by default, er can also hold them as long as the threaded end can pass through the collet body.

You will find that any given pitch of thread is the same depth, ie, a 6mm X 1mm pitch thread depth would be identical to a 20 X 1mm pitch thread. So if you need to make a unique diameter thread with a standard pitch, you can use the figures for that pitch of thread. If possible, you can get a perfect fit by using the mating part as a gauge and creep up on the last bit. If the fit is critical, but the mating part cannot be used as a gauge, you could make a threaded gauge of the same size to use instead.

**LINK**

The Smart & Brown model A uses a 25mm x 3mm thick belt with a join in it sucessfully, I believe the belt and joining parts came from Lathes UK. I'm not sure if a 2mm thick belt can be joined mechanically, though.

I would feel safer using the full length of the collet. 16mm collets will always be full length inside.

Howard's suggestion of sharing the rework at both ends would be my choice if there was enough material.

I used the rorary table to produce a similar type of drive, but with 7 segments, 51 degrees 26 minutes, approximately for a long handle for the knee of the Tom senior mill when there was a heavy weight on the bed.

It is amazing exactly what some people get up to to justify their existance.

This is what the museum's drill mill looks like with an ARC 125mm vise and also with a 100mm Bison vise. I bought the ARC vise for its extra opening for a larger job. The drill mill is one of the larger sizes, the bed is 8" by 28 1/2" and has a 500mm X travel.

Edited By old mart on 11/08/2021 19:30:44

It's very satisfying to hear of a sucessful outcome, your machine is better than new now and everyone has learned something to boot.