All things Beaver Mill

As a 'for info.' for other owners, if you search around the terms 'Bridgeport splne noise' or 'Bridgeport spline knock' or similar, you can see solutions that people have come up with to address the problem.

Generally they involve preloading the sliding male splines on the quill against the fixed female splines in the drive pulley. A Bridgeport is a bit different to a Beaver in that the male splines poke well up above the drive pulley when the quill is retracted.

On a PAL at least, the male splines are not visible so a slightly different approach might be needed. My head only really makes noise when flycutting or facemilling. Standard cutters are OK. See below for what I have made, noting that it does stop use of the quill when installed (but facemilling or flycutting with the quill sticking out is probably not a good idea anyway).

Hi

I too have a noisy VBRP mark 1 like Brian’s there was nothing between the bearings supporting the driven pulley, so I made a sleeve to allow me to tighten the pulley to the shaft. But I still have a metallic chattering noise which I think is from the coupling between the spindle and the pulley, should the dogs be tapered so there in no backlash? I also wondered if a stronger spring would help?

Any more ideas out there?

thanks Ian

One more thing should it have a spindle lock?

Ian

There was nothing between the bearing inner races of the driven pulley originally. A fitted spacer is probably an excelent idea to allow one to have a controlled pre-load while not needing surgical precision on the shifting spanner during tightening!

If the chattering noise occurs when there is no load, and no loose drawbar, then the pulley shaft and gear shaft probably arent lined up.

On the top aluminium cover there should be four cap head screws pulling the bearing carrier towards the cover and four allen grub screws pushing it away from the cover. You need to adjust these so that the dogs on the pulley shaft line up with the dogs on the gear shaft. The easiest way I've found is to start with all the screws loose, then gently nip up the grub screws until you get contact. Then gently nip up the capheead screws to take some straing. After that, with the mill running (and you probably standing on the table!) tweak the alignment by loosening/tightening adjacent caphead and grub screws to get the quietest running.

The dogs on mine are tapered, but I don't know if that was by design or has just happened over the last 60 odd years.The two sets of dogs do seem to match together without any play (unlike the spindle splines)

It should have a spindle lock, but they never designed one in to the Mk1... Simple way around this is a lightweight spanner on the drawbar nut (aluminium ratchet socket wrench in my case) and a sharp rap with a bit of bar or a 1 lb hammer.

In the tightening direction, one or more sharp tugs on the wrench handle usually seems to do the job. Lower speed belt settings make the technique more effective, which is good, since you nromally want a tighter grip on larger cutters.

Thank you Mark , just read your reply to Ian and was delighted that Your reply matched my findings exactly. I was wondering about the four grub screws on the to cover. I had assumed wrongly this had been a modification by someone to take up wear, but without to top cover having any dowl pins this would make sense. And as your comments suggest in my case I definitely found it beneficial to tweak them until quietest running achieved. and I would think any misalignment of dogs would result in rapid wear. I assumed the tappers dogs were to take up a certain amount of slack as wear takes place. From what I recal Ten years ago,my Bridgeport has a similar set up. As there are no manuals for the BVRP mk1 your comments are very reassuring to know.

Thanks Mark, I took it apart for the 5th time and checked the dog engagement and there was some play, I then noticed the lower teeth were bottoming out on the toothed pulley, a quick skim on the lathe sorted it out and now they are quite a snug fit. The noise has reduced significantly now. I will have a look at aligning the pulley on the grub screws to see if it helps

ian

There must be some sort of plague of Beaver head work going around. I've got mine apart again so I can get the dimensions right to replace the gear shifting fork and slipper blocks on the back gear with an 80x100x10mm bearing, carrier and appropriate shifting fork.

When I originally rebuilt the machine, the shifting fork was worn through at the ends and the slipper blocks were almost worn away. I weld repaired the fork, cleaned up the groove on the pulley and made new slipper blocks out of expensive phosphor bronze.

In the relatively small amount of use it's had since then (compared with a production shop), the slipper blocks are wearing again. So the plan is to use the ball bearing in place of slipper blocks.

It's odd how many improvements there were between the Mk1 and the Mk2 (same on the Hardinge lathes)!

This photo shows the #40 spindle bore and face after grinding, run out on bore and face is now less than .0001" (.0025mm). The picture does not show up very well but the finish produced by the TPG is very good.

Nice!

Does anyone with a Mk2 know where the return spring for the quill is located, the parts manual does not show it.

I need to get a bit more tension on mine somehow but I don't want to start pulling things apart until I know how the spring is set up.

Haven't got a Mk2, but most mills have the return spring in a housing right beside the quill downfeed handle.

Usual method, if you need more tension is to wind the quill down till the pinion is off the end of the rack, supporting its weight as you do so (after removing the depth stops/covers etc. that will prevent the quill from going that far), then give the handle a bit more rotation to wind the spring up some more. Then push the quill back up so its rack engages the pinion, reassemble and bob's your uncle.

The fun starts when the clock spring decides that it isn't going to play and either breaks at the end of becomes unhooked from the inner and outer retaining screws. Then you have to take the cover off and hook it back together...

It's not a simple matter of rotating the pinion a bit because that will move the position of the dowel pin that acts as the Zero position stop. There must be some way to apply more tension directly to the spring but I think that the spring is either in the Quill casting or the feed gearbox housing on the left, it is not on the handle side of the head.

Edited By Lex Davis on 04/09/2020 04:37:46

It is on the handle side of the head.

Look here:

https://www.model-engineer.co.uk/forums/postings.asp?th=91397&p=2

post by Paul Major 09/02/14 23:03:40, sixth photo of post.

The spring is inside the left hand gear.

Thanks for the information DC, I completely missed the spring in the parts manual but it definitely is in the down feed handle gear as you and Mark suggested.

Before I start making a new dial, as one of mine is missing,though I would ask the question here first - what are my chances of finding one of these anywhere around the world? I need the 0- .200" dial for the x axis.

A handy addition to the Beaver that I have been working on for the last few days. I think it looks a bit "agricultural" but it is very useful and easily removed if required.

Hi

another question my MK1 has grease nipples on the slides, is this correct as I thought oil would be a better lubricant?

Ian

They are oil nipples, not grease nipples.

If grease has been used on the ways, remove the table and the knee and clean the oilways out with oil!

Edited By Mark Rand on 15/09/2020 17:48:24

Hi

I have a vbrp mk2 beavermill and i could not find anywhere what oils go into the head?

Could someone help with what oil goes in there?

Thank you.

The oils specified in the 1970"s operation manual are no longer available, although alternative oils of equivalent specification are. I just use ISO68 hydraulic oil as most of it leaks out anyway. Any oil of roughly the correct viscosity is probably better than running it dry.