Member postings for Robin

Maybe it needed the extra power because it had to lift a Saturn 5

Posted by Mark Rand on 24/11/2018 00:29:25:It's just a stage in the progression towards punt guns . (spent my childhood in Norfolk).

No, I don't want one.

I want two

Would it shrink on? That is not a suggestion so much as a question

Hi Robert

I'm not quite sure why but I seem to be collecting blunderbusses, it's probably just a phase I'm going through

I'm not sure I want to tell, because you lot might tell me it isn't what I bought it as and burst my bubble. I really enjoy owning the rifling cutter for a Lewis gun

SODu if you want examples, try Googling "Nanny State".

Thanks for that useful warning. Did you know that according to Arthur Ransome, duffers are likely to meet a watery end? Take care around boats. Here's something else I should not have...

I like that... a ,125" lead screw times 120 divide by 127 equals exactly 3mm

Last 2mm pitch I cut I used 25:40...

.125" x 25 / 40 = 1.984mm that's 16 um short.

I wouldn't suggest lead acetate, the so called Sugar of Lead ,as a sweetener. That's been tried in the past with terrible consequences. I have a pot of it for making slow match, it burns without the hard coal you get with saltpetre.

Anyway, how is the lead in the solder going to poison me? Not by inhalation, I do a lot of soldering and it is always the tin that boils off leaving a pasty lead crust behind. I suppose not washing my hands before eating a sandwich might be my downfall.

I remember some workman showing us a terrible cut across the palm side of his fingers he had got from lead flashing. He had a decorative hankie knotted over it and everyone was muttering about lead poisoning. This was the 1950's and I was already expert on skinned knees, I reckoned it just looked like it needed drying out.

Anyway, I appreciate your concern, I will take more care around the dreaded Plum bum and strongly suggest nobody looks to me for Health and Safety advice.

Here's a piece of lead/pewter, an apostle cap, a dinky spout for pouring gunpowder into your matchlock musq't.

It must have been lost c1640 then waited for a metal detectorist to visit the battlefield, recover it and sell it on eBay.

The lead has hardly degraded, even the little loops for the strings are stil there. I don't think lead in landfill is half the problem it is made out to be.

I've missed a lot of this but it looks wonderful. To hob a 14 tooth gear with a 40:1 reduction worm requires virtual gearing 14:40

Assuming 400 half steps/rev on the motor it works out beautifully 400 x 14 / 40 requires 140 steps/rev.

I'm guessing you are 3d printing quadrature encoders to go on the spindle.

The easiest way to read a quadrature encoder is to combine new data with previous data, turning 2 bits in to 4 and then using a look up table to get step and direction.

I know I am a nosey git, but am I right?

But it is glorious, if it lasts for a week then I will count it as money well spent

After having to find a torch to read the jaw numbers in my lathe chuck on Saturday, today I replaced all the flourescent tubes and starters in the workshop. Cost me 50 quid and now I'm thinking I might need to buy some sun glasses to make it habitable

We are not going to agree on anything, but I still like the way you think

Robin

I am not sure about that, but I am not here to argue

I left it unattended on a slow feed once. The saddle pushed the headstock back until it snapped the bottom of the gear quadrant off and graunched the lead screw under the split nut. Seeing as how both results would stop the saddle I think it is most unfair that I had to suffer both. Anyway, since then I leave a slow feed gear set up and avoid thread cutting. Too much regret when I have to hold the pieces together whild locking the quadrant.

Perhaps I exaggerate, if I really cared I would drill and screw the quadrant it back together

That's what I have on the table inside the gear cover. BUT my simple 25:40 does not involve buying a new 63 tooth change wheel and is out by .016 mm which beats their .084 mm

Very odd.

Is there some advantage to erring on the plus side?

I got Alibre on a £99 special offer thing and I have renewed on special offers since then. I currently have v2017 on my PC. I think I prefer Fusion. However, unlike Fusion only your maintenance contract expires not the whole caboodle.

I got Fusion on a 2 years for the price of 1 special offer and then rummaged around to turn off the auto-renew. If I draw something I need to keep I will have to make sure I have a real copy and none of that cloud nonsense.

I use a cheap AutoCAD clone called ProgeCAD. It works okay, it has a few bad habits but nothing I cannot work around. I use Alibre and Fusion for 3D printing, I use ProgeCAD for machining 2.5D. I build the shape using circles, lines and arcs then extrude them vertically using the elev and thickness variables. I export as a .dxf and them process that. I have plans to try Fusion tool paths, looks like fun.

OTOH, I use Protel Autotrax for PCB design so what I do is probably not worth your consideration

Edited By JasonB on 28/10/2018 20:18:51

Useful post. So I want to cut about an inch of left handed, M30x2 thread for which I have a die nut.

I divide the leadscrew 3.175mm pitch by my required 2mm pitch then multiply by 25 teeth on the head stock and find I need a 39.6875 tooth gear on the lead screw.

Dont' have one of them but I do have a 40t.

3.175mm x 25 / 40 = 1.984375, so over my 12 threads I will be out by 0.1875mm, about 7 thou.

Only tricky bit is I will need 3 idlers to get the bottom gear turning in the same direction as the top for a left hand thread.

That wasn't nearly as hard/expensive as I expected. Well done Brian

Edited By Robin on 28/10/2018 15:12:59

That looks so far out it isn't true (as they say).

Perhaps it is the camera angle or something

I was given a compressor because my brother couldn't stand the NOISE. Neither could I.

I now have 2 Bambi's, permanently on and no louder than the fridge, (probably because they use fridge compressors)