Maximat V10P runs out

[Africanimp]

They are lock screws to the threaded rod they are going into?

But why would the threaded stud have a lock screw ??

Are they there to push the gear head into line, as in the threads are say 8mm diameter in a 9.5mm diameter hole, that would give plenty of adjustment?

Its the same on the other side.

With the nuts removed and a mirror inserted underneath I may see that the stud hole is large enough to allow adjustment?

I will be checking this idea out in the morning!

[JohnHaine]

Before you start trying to realign the headstock, look again at bed twist. No point in using a carpenter's or builder's level, you need a proper machinist's level which is much more sensitive. This topic has been discussed to death over on the model engineer site:

https://www.model-engineer.co.uk/

I suggest you search there, there have been a number of threads on the topic. Ideally the base needs to be at least resting on a level floor if not bolted down, or have levelling screws so it can be sitting on the floor with no distortion. If the base can distort the bed it will. Then use the mounting screws, which may well have a levelling nut arrangement, to adjust the twist out of the bed all the way along. Make final adjustments doing test cuts.

By the way you are not seeing runout, it's taper. Run out is when a shaft is not running concentric.

My Myford Super 7 is mounted on a pressed steel stand which has 4 mounting feet, each one with a screw adjustment for levelling. So I get the top of the stand level using a machinist's level, then adjust the bed mounting bolts to get the top of the bed level transversely at both ends and the middle, turning the level through 180* at each position. Of course it doesn't have to be level as such, just straight, but "level-ness" is a convenient way to do this.

[Africanimp]

Thanks for your comments, I am working with what is available, right now the Stabila construction level is what is to hand, if a more accurate one becomes available I will re do the job. I did however find that the tailstock end was out by 4.25mm which was a surprise.

The original Maximate stand is not bolted down, it is loose standing and on a clean concrete surface, its firm and does not rock or move.

Thanks also for the mention of Taper as against my Run Out, bit by bit I am learning!

[Africanimp]

An idea that the gear head box can be adjusted via the grub screw numbered 48 in the parts list holds no water, this is what I see in a mirror when the nut has been removed, there is no extra space seen for adjustment that I can see?

[Africanimp]

My search for a parts name page has found the parts drawing and a list of names, part number 48 is a Socket Screw, so its not for adjusting the gearhead?

[Africanimp]

I then refaced the back plate and the dial gauge gave me a very nice zero read out, as in nothing. The center shaft required a small trim as well, otherwise the chuck was going to ride on it.

[mekanik]

Photo in post No 29 is The screwcutting gearbox,

[Africanimp]

I mentioned the chuck back plate was refaced, well as a way of running through the possible errors I have rechecked the back plate and found that it had an error of 0.0003" which is what the error in my machining is, could that be the reason for error?

[Africanimp]

[Africanimp]

With the recut of the back plate I saw a zero reading on the dial gauge in all areas! Plus I had also removed the problem with the 0.003" Taper error that I thought the gear head had?