Member postings for Ace Chandler

Our conservatory is being replaced - it has 3 large RSJ's that came out of the old one that are now surplus to requirements.

It seems a shame to scrap them. I don't have an immediate "construction" use for them, but was considering hacking them up with an angle grinder and storing the steel for use with general machining.

I don't know if they are in the category of things like Rebar which I beleive as being well documented as terrible/horrible to machine.

So basic question is does RSJ Steel machine/weld well?

Thanks, Ace

Indeed - my ability to grind tools well is definitley 'basic' at the moment, so that's the next skill to learn. At present, I'm a bit ham fisted with the bench grinder and so the faces of my tool look "not flat", they look more like geodesic domes at present

all grist to the mill though on a journey of learning.

I posted a thread a while ago on my poor surface finish.

https://www.model-engineer.co.uk/forums/postings.asp?th=165810

Since then, I've been persevering and things have been getting better. I've discovered:

• Life seems easier with HSS than carbide - its also cheaper too
• I've tried to be more religious with using the dead centre to hold the other end of the stock still which I think reduces chatter
• I've tried to keep the tool closer to the toolpost so that less is sticking out, again, aiming to reduce chatter.
• I try and use the autofeed all the time as it gives a smoother pass over the surface

one odd thing I still can't track down is that facing cuts are way smoother thatn normal turning operations. I get that lovely crisp sound, no vibes through the machine and a nice clean trace of swarf. It could be that I'm not very good with sharpening HSS yet and somehow whatever point I'm acheiving is better for a facing cut than a regular turning operation.

Anyway - things are better now than they were, but still am finishing off the peices with some emery paper to get a reallly nice finish.

any other suggestions are very welcome.

/A

As a bit of a thought experiment, I was curious what high quality medium sized lathes exist.

I have an axminster SC2 lathe and the fit and finish aren't great - now I've tightened everything up a bit, it's not super bad, but everything has slightly more movement/wiggle than one might like.

This is a thought experiment because I need to learn my craft a little on the one I have before I really consider upgrading.

By "Medium sized", I mean the next size up from the Sherline/Cowells ones, something like the SC4 lathe..

I think its pretty well documented that the same factory in china is making lots of lathes for Arc, Axminster, Clarke and maybe warco, so I assume they are all of a similar quality.

Other than things like the Wabeco, is there anything in the next 'quality bracket' up? I see folks on youtube using things like the Precision Matthews lathes, but they seem like they are US only.

Update - I've reattached the shear plates to the back and things seem to be moderately back to normal.

I actually took most of the machine apart and cleaned and re-tightened most of the bolts (the one on the cross slide was loose too!).

Its much better now, although still a little bit of racking - i.e vertically when you look down from above, the carriage twists very slightly. I'll have to think about how I can trim this as the carriage doesn't seem to have Gib adjustments like the cross slide does. If I tighten the shear plates up too much then you can't actually move the cross slide which isn't optimal

...but it's vastly better than it was (unsurprisingly)

Thanks again for the advice.

Thanks very much everyone, really appreciate the details. - I think I'll be getting the 2.7 from Arc.

Wow - and the Sieg mill is quite a lot cheaper than the axminster one - like by nearly £500!

are you happy with it?

Wondered if anyone had a perspective on these two mills, For reference - here are the two links.

2.7 mill vs SX2

I called Axminster to ask (mindful of the fact that one is nearly twice the price of the other) - and they told me that the 2.7 mill is "Engineer Grade" whereas the SX2 mill is "Hobby" grade, which means that the castings and other moving parts are of a much higher quality.

I was interested to see if anyone had direct experience.

Many thanks, ace

yeah , so I've bought some new shear plates (your helpful link tells me that's what they are called) - I'll replace it and then see where I am.

I guess worst case, I might also have to buy a new leadscrew? - does that sound about right, or could any damage be more extensive than that ?

Would anyone happen to have one of these and can confirm if a part is missing or not (SC2)?

I took a photo shown below (the excessive red is my poor graphics package!) - but I think there is supposed to be strip under the back of the carriage that bolts in and then overhangs under the ways to keep it down (where the red arrow is). It would be great if someone could take a photo of theirs to show me what it's *supposed* to look like.

Thanks much in advance. The help is really appreciated.

asdf

Edited By Ace Chandler on 18/01/2021 17:14:42

Thank you - I will take a few more pictures and post back with a response once I've had a chance to look tonight.

Hi - I've just moved house and installed my lathe into my garage (axminster mini lathe)- it's bolted down etc, but I noticed that the carriage seems quite wobbly on the back ways. There is a video below I recorded to try and demonstrate the problem. I should confess it might have always been like that and I've only just noticed!

I noted there are 4 grub screws (2 on the top, and 2 on the bottom) on the carriage at the back - I think these might be the gib adjustment, I've played a bit with these to try and adjust it out, but it's still quite wobbly, even with the grubs in quite tightly.

Also, the "clamp" (apologies if that's the wrong technical term!) on the front ways was pretty loose, so I tightened this up, but it still wobbles on the back ways.

I wondered if I might need to make a shim to take up the slack

Many Thanks in advance.

yup - and my googling tells me that 12L14 steel is called EN1A here in the UK which is what I purchased.

...no more playing with bolts.. .back to practicing

Noted, although interested in why that is.. do they just make bolts out of cheap (or at least hard to machine) steel?

Yes, I bought some EN1A from ebay (per previous post on here, I at least *think* it's EN1A).

I've played with some turning down some bolts (M10 ones that I had to hand), but I don't think I'd try rebar

I made a little progress and some improvements here.

1. Bolted down the lathe to the bench, it was moving a little, I suspect that the vibrations weren't helping

2. Making more use of the power feed. the hand feed isn't geared, so it moves too fast if you turn with the handle on the wheel, therefore you have to turn the wheel with your hand, I think when I readjusted my hand position for the next bit of the turn, I was getting little lines as the tool was paused for a while. I'm sure I could develop some two-handed technique so it doesn't stop while I adjust hand position - but using the power feed seems to yeild better results.

3. As advised here, I'm taking slightly heavier cuts, which yields better results.

I'll try and video the set up so that people can see and observe if there is anything else that's obvious that I'm doing wrong.

Thanks a lot guys - this is a really helpful set of links. Much appreciated.

In this thread I started on surface finish, I mentioned that I'd bought some EN1A steel from ebay as my research had said this is the easiest to machine. Someone then quite rightly asked "how do you know that's what you were sent?"

I wondered if people had any recommended, trusted suppliers (ebay sellers or otherwise) of material they could share. I'm located in Kent in case there are any places that are actually local to me. I've been using ebay and trying to stick to people with decent recommended feedback to source my material, but perhaps people have other suggestions on good places to buy from.

Thanks, Ace

could you help me understand a bit more what the first point precisely means? - does "slight drag" mean that it should feel a little tighter than one might intuitively think was needed?

@Martin - Thanks a lot for the feedback. Based on that calculator, I'm going too fast on the speed I think.