Member postings for Martin Currie

Hello everyone

I'm currently working on a pen made from stainless steel utilising a shake mechanism I got from a German supplier, the shake mechanism has an obscure thread on it M7.5x0.5.

I bought a tap for this and it’s worked fine but I’m now trying to machine an external thread for the top of the pen body and I can’t find any information for the max and min diameter for the external threads so I can cut these on the lathe.

I’ve got a copy of machinery handbook, but can find any information on this particular thread, I’ve even tried subtracting the pitch from the M7.5, but it’s really slack…

Can anyone help?

Cheers

Martin

Edited By Martin Currie on 24/08/2023 18:05:21

So guys what's would be better SAE 660 Bearing bronze or brass? I got a piece of round bar that's SAE 660 based on watching other machinists on youtube making leadscrews nuts?

Got me wondering now......

Martin

Hello Guys

Thank you so much for all the detailed replies on the various types of mild steel. I'll have a look into the EN1A and the leaded type and see how I go with this.

I noted that there were a few questions asking why I hadn’t thought of cast iron for some of the engine parts, its just a matter of experience or lack of it, and the need of time to source materials.

I live in a very rural area on the west coast of Scotland and delivery is a premium for materials.

I’ve spotted a few vendors on here and I’ll have a look at their stock list, also in I’m looking for a chunk of PB square stock to machine a new leadscrew nut for the cross slide on my Warco GH1230. From the factory it’s  got a horrifically machined chunk of brass, I think.

Thanks for all the input guys I really appreciate all the help.

Martin

Edited By Martin Currie on 09/02/2023 08:40:44

Hello everyone

I’m looking for some help regarding material choices, I’m new to the hobby and bought on

eBay, shortly after buying my lathe a 20kg pack of bright mild steel. Well, this has been crap, no idea what grade it is, it wasn’t expensive and got me making chips. But now I’m looking for material to build my “Bogstandard” X2 steam engine and I want a nice grade of mild steel that will produce a good finish using carbide and HSS tooling.

What should I buy? I’m looking to machine cylinder block, crank webs, crossheads, and the eccentric cams, so I want something that’s not going to bend like a banana after milling.

Guys, I’m pretty much green in the hobby so any specifics grades, sources etc. would be much appreciated. I hear online everyone talking about these 4141 (Cousins over the water) stresses relieved steel, what is this and would this help me? Do we have an equivalent in this country?

Thanks for looking guys

Martin

Just a quick update, i was having some rigidity issues with my small machine so I upgraded to new Warco Super major.

I enlisted a little help from Jon at “Jons workshop”… Making A Marine Engine Twin Cylinder Block Start To Finish

Have a look guy’s, drawings are complete if anyone wants a copy, I’ll be amending/improving as I progress.

Martin

https://youtu.be/USuIk0mxYT0

I like the idea of having a small tooling system, I've ordered the ER20 short straight shank holder form APT in the UK, I'll have a quality R8 20mm collet for holding in the spindle and then buy a few more or the ER20 holders so I can have all my end mills that I'll be using for that particular job set up in there holders with the offsets programmed into the DRO for quick changing during jobs.

I did look at the Tormach TTS, holders but the price of each holder a too expensive compared to APT's prices. and with APT I know there tooling is great quality and an affordable price..

Hello Guys

Thanks for the further comments, I was a little confused following some of the later comments, but now I’ve decided to go along the route of a ER20 collets. I’ve spoken to APT and will change my order.

The reason behind this change is that I use milling cutters all from APT 4, 6 ,8, 10 & 12mm.

I like the idea of having a smaller size chuck for visibility, chip clearance and having easy access to allow coolant into and around the work piece. I had a look at the dimensions of the ER20 holder and I agree with the above it’ll allow good visibility and I like the slenderness of the chuck compared to the ER32.

I believe this will work well for my applications going forward.

APT have a great selection of the collets that I’ll need, and they also state the TIR, I’ll begin with these and see where I need to go from there onwards.

If I need a larger milling cutter, I’ll be looking at a fly cutter or an R8 face mill of sorts.

Thanks for all your help.

Martin

Guys

Thank you so much for all the feedback on the R8 collets and ER 32 system.

I'm going to mix and match to get the best of both worlds as they say. I've ordered a set of ER32 collets and chuck from APT. I'll get a few R8 collets also.

Thanks again guys

Martin

Hello Guys

I've just recently bought myself a new Warco Super Major mill direct from Warco and I'm looking for some advice on buying an R8 keyless drill chuck and R8 collets to hold my end mills.

APT in Glasgow is my main supplier for HSS/carbide milling cutters, I have noted that on their website they sell R8 drill chucks with TIR 0.05mm, I’d like people’s opinions on this, would this be classed as a low amount of runout for a drill chuck. My knowledge on this subject is a little bit limited, so any feedback would be appreciated.

Also, I haven’t decided if I’m gong to use R8 5C collets to hold my end mills or use an ER32 R8 collet holder.

What would be the most optimum setup for this mill? I like the idea of maximizing vertical space with the R8 collets instead of losing a few inches with the ER32 system. also what about runout on collets is there a particular brand that i should look to buy either ER32 collets/holder and the direct R8 collets?

Thanks for your help.

Martin

Back in late October of 2021 I came across the hand drawn sketches of the late John “Bogstandard” Moore, marine steam engine. I had only recently taken up machining as a hobby and decided that this little engine, is what I wanted to build as my first scratch built model engine.

Initially began re-drawing the hand drawn sketches into Fusion360 as 3D modelling has been a longstanding hobby of mine over the past 6-7 years. Halfway through the design/drafting process I decided that why not enlarge the model from its original scale by a factor of 2. I thought that this would produce a lovely sized model that would make a great displace piece.

The finished engine will measure somewhere in the region of 250x100x250

These plans will be available shortly for anyone wishing a copy provided that any feedback, improvements, and suggestions are passed back to me so that I can update and improve the drawings. These plans will be FREE of charge as a mark of respect to Bogstandards and his original drawings.

At the end of January 2022, I completed the designs and have produced a set of drawings that runs to 27 pages. I really enjoyed the project and now mid-February of 2022; I have begun construction of the engine.

Today I began with the base plate, making this from 10mm aluminium plate. I squared up the plate and then laid out all the holes on the plate. The outer holes are for fixing the base to a bed of some sort with four of these holes used to fasten the cylinder block support columns above the base plate.

The 8 inner holes are tapped to hold the bearing blocks that crank shafts will pass through.

I plunge milled the pockets out of the base plate

once the bulk of the material was removed in swept the outer faces of the pockets taking them to final dimensions and producing a nice finish.

Below is the finished base plate,

all that is left to do is de-burr a few edges and add some external radius when my belt sander arrives in the coming week or so.

I'm new to machining and engineering, this is something I've always wanted to do and I'd love to hear any feed back that anyone has.

If anyone would like a copy of the drawings, please PM. I wont be releasing publicly yet, as in posting to a forum notice board, until I've completed the build and highlighted any flaws along the way, however if anyone would like to cast there eye over the drawings then please feel free to contact me.

Cheers Guys

Martin

Edited By Martin Currie 2 on 16/02/2022 21:24:56

Edited By Martin Currie 2 on 16/02/2022 21:27:06

Guys...

Thank you all for the comments left over the past few days.. these are all great and I'll have a look as soon as I get home. I'm in the North Pacific at the moment on a ship, so thought I'd use the time here to diagnose and do a little research to determine the issue.

Dave, I never thought about looking at the rack, I've replaced a few of the cap screws that were originally fitted to the lathe as I wasn't happy with the quality of them. I started with the tail stock offset dogged grub screws, one actually sheared and I was fortunate enough to get it out. I replaced these with nice stainless steel grub dogged screws.......

Overall I'm very impressed with the GH1230, its an extremely accurate lathe.

Thanks again guys

Martin

Hello Guys

I’ve recently bought a Warco GH1230 gear head lathe and I’m absolutely delighted with the machine. One thing I’ve notice is that on the carriage I’ve got almost a qtr. to half turn (possibly slightly more&hellip of backlash on the carriage hand wheel. I spotted this recently when making a slitting saw arbor, I was turning down a piece of stock and was using the power feed on the Z axis, I notice the hand wheel turning for almost a half turn before the carriage began to move. If its backlash I’m not so fussed as this machine has a 3 axis DRO fitted as standard, I’m more worried that there something worn, stripped or loose. When I first started using the lathe, I had to contact Warco for a new brass nut for the cross-slide leadscrew, as it was stripped straight out of the box.

Warco were amazing and replaced the entire leadscrew and nut for me!!

If I wined the handle out and then a turn the opposite direction and engage the power feed the carriage and handle move together immediately.

I’m just a beginner and wat to check to see if its just backlash or could there something else, I’m sure it’s just backlash…

Martin

Guys

Thank you all very much for these informative replies to my question on cutters, I'll have a look into ARC, APT's website. I had sent APT an email about two weeks ago, but yet to get a reply.

I'll get myself an ER40 collet system, I've decided on the 40's and this will work well alongside my lathe also.

Thanks once again

Martin

Hello everyone

I'm completely new to milling and have recently bought myself a secondhand Chester Champion 20VS mill. I noticed that this mill was the same as the G0704 made by Grizzly and I have ordered from the US, a belt conversion for this mill along with replacement bearings for the belt drive and also the spindle. I bought SKF bearings which are high end quality and I'm looking forward to making these mods to the mill.

As mentioned above I'm new to milling and I'd be grateful if someone could point me in the direction of a good quality milling cutters. I'm hoping to start building model steam engine kits going forward and if i can a locomotive too.

I know nothing about milling cutters other than what I've seen online any advice would be most welcome. I'll be using either a ER40 or 32 collett system to hold these cutters and this will be great for my GH1230 lathe that I've just bought.

Any tips pointers, advice would be greatly appreciated.

Martin