Member postings for Andrew Tinsley

Odd that the late George Thomas was quite a fan of a loose register on the back plate. Following in the footsteps of Commander Barker who used the method for very accurate work.

Andrew.

There should be no problem with a 17.5 degree pressure angle as long as all the meshing gears are the same.

Not sure about the minimum number of teeth, but I would not go below 20 teeth as I have had some nasties when trying for much less. Not sure if the problem was an inherent one or just poor execution on my part.

Andrew.

Hello again Howard.

Just to be pedantic, I have a Mitutoyo vernier caliper with a "glass", It houses a dial for the least significant number!

Best Regards,

Andrew,

P.S. the Gunson twin carb balancer has been used this week. I shall have the MGB on the road after the lockdown. Thanks again.

Hello Hopper,

Yes indeed, I will be using a V tool to rough out and a tap to finish it. I doubt that my eyesight would be up to grinding an accurate HSS tool to ACME shape. Well fractionally narrower than a true ACME, so I can clean up the flanks if necessary.

You make an interesting point about the locking mechanism. I never thought of that. It could explain why there is so much radial play in the nut. There appears to be more radial wear than axial, something I have not seen before.

Thanks again,

Andrew.

Hello Old Mart,

As I said above the size is 7/16" x 10tpi . This means that none of the MaccModel or Metal 4U cast SAE660 rod with hole is going to work, as the cast in holes are all too big.

Thanks,

Andrew.

Hello Hopper,

I did describe the application in another earlier post, but only got one reply, so I didn't bother to repeat all that again! I shall take your advice and use the LG2. Is that material the one that machines like mild steel? I know some of the bronze / gunmetal family can be a swine to work with.

Thanks,

Andrew.

I have used white metal often in a preserved railway context and I know the differences between grades! Compared to a simple turning and thread cutting exercise, it really isn't worth considering in my opinion.

The nut in question is off the downfeed of my Royal shaper. It isn't brass and has worn very badly. I appreciate that 50 thou backlash is neither here nor there in such a context. I am replacing the nut, purely because the backlash irritates me!

From what has been said, I might as well make a couple out of brass and be done with it! Much to my surprise I already have a 7/16" X 10tpi Acme tap in my collection, so all I need is a lump of brass.

Thanks everyone for the help and suggestions.

Andrew.

Thanks Hopper and Old Mart. Now I am confused, I was under the impression that gunmetal and bronze were somewhat different in alloy composition. I also thought that it was phospher bronze that could wear the leadscrew excessively and that gunmetal in fact was much better!

My very worn nut isn't brass because of its more reddish tinge I assumed it was either bronze or gunmetal. Anyone know for definite about the relative merits of brass, bronze, phospher bronze and gunmetal for leadscrew applications? Whatever material my nut is, it has certainly worn badly in both the axial and radial dimensions, the leadscrew shows no appreciable wear.

Thanks,

Andrew.

Anyone know of a source please. I have tried several of the usual suppliers without any luck.

Andrew.

I was looking in the vacuum cleaner skip at my local tip (sorry, recycling center!). Well over half the Vacs were Dysons. Hope his ventilators work better than his vacuums.

Andrew.

Deleat please!

Edited By Andrew Tinsley on 30/03/2020 16:23:57

Edited By Andrew Tinsley on 30/03/2020 16:24:52

Thanks Brian,

I had not thought of that.

Andrew.

Hello everyone,

I am sorting out some inherited gear cutters. Most of them have the DP and tooth range stamped on them some also have the Pressure angle too.

There are quite a few that have simply P stamped on them where I would expect it to be DP. Do I assume that the P is just a shortened form of DP?

A few have nothing except the manufacturer's number, which I assume are "specials"?

Thanks,

Andrew.

I am about a third of the way through Roger Penrose's "Road to Reality". Certainly a very interesting read. Should take me to the end of the 12 weeks of self isolation.

Andrew.

I have made half a dozen loco boilers from 3.5" gauge to 7.25" gauge. Also a series of smaller boilers for stationary engines.

I have had virtually no problems with poor penetration of joints. I was idly thumbing through Tubal Cain's book on soldering and brazing, when I saw a chapter about setting up the job with the correct capillary gaps. Suddenly I had a guilty feeling, because I have never knowingly bothered about this aspect of silver soldering!

I must have been very lucky. So to correct my bad ways, how does everyone else produce the ideal gap?

Andrew.

Hello Nigel,

Yes I am aware of the time limit. I should have made clear that the edit function isn't there when the post is made! Sometimes it is and sometimes not. If I make a mistake I always try to edit it out, but if the edit button isn't there at moment of first posting, then one is somewhat stuck!

Andrew.

NDIY. I did not have the opportunity to edit the post. For some strange reason, about 50% of the time, there is an edit option available after one has posted. For the other 50% of posts, it isn't there.

Perhaps you could explain this phenomena.

Andrew.

Thanks Dave,

Much appreciated.

Andrew.

Having a problem sorting out which desoldering iron on Amazon is being recommended! Can anyone give me a link please?

Thanks,

Andrew.

Thank you all,

I shall now look for a small vice for my shaper. Could be a long wait!

Regards,

Andrew.