Here is a list of all the postings Pete Rimmer has made in our forums. Click on a thread name to jump to the thread.
|Thread: Balzer relieving attachment working model|
Here's a link to the video of me working the model. Sorry about the white balance, it looked fine on my phone, only came out too white when I converted it for sharing.
ARG, looks like dropbox has ruined the quality. I'll have to fix it later.
Edited By Pete Rimmer on 11/12/2019 14:11:22
The secret is in this gear, in the pic it's the one with the peg that stops it turning. The top half has 4 more teeth than the bottom half. Because the flying pinion HAS to mesh with both gears, the left gear is advanced 4 teeth during the bottom half of the rotation.
I originally printed the gears as 14.5PA but found that the teeth were too fine for the printer. Just like 3-d printed holes come out under-sized the teeth were slightly crowding into the gaps. I got over this by increasing the PA to 25 degrees which made the teeth more triangle-shaped, and printing the gears on a raft to raise them off the heated bed somewhat. Later I increased the PA of the bottom half teeth of the split gear even further to 30 degrees, to aid the meshing of the pinion over the mis-matched tooth size.
The actual cutting action is caused by the two end-pivots being off-set by 1mm so as the workpiece 'speeds up' it also moves towards the cutter,
Edited By Pete Rimmer on 11/12/2019 11:06:56
Being new to 3d printing (4 days in) and needing something interesting to really get stuck in to learning how to draw and print models I decided to see if I could produce a working model of the Balzer device. Here are the results. It's definitely a bit rough and ready, and a couple of things need a tweak here and there but it's a fully working model operated by the hand crank.
Hope you like it. I'll see if I can take a short video of it working. All-white is a bit of a devil to photograph I have found.
The gears took a bit of designing. One of them has two different DP teeth on the same gear and the small orbiting one has a different pressure angle to the other two, in order to make everything mesh.
|Thread: Run outs|
Check the runout of the chuck itself before going ape on the nut. Use an indicator on the inside taper. .01 runout could be the spindle, the chuck or just a speck of swarf somewhere.
|Thread: making Taps and dies|
Luckily for you, someone has archived the site on the wayback machine:
|Thread: Tool steel - Beginners guide ?|
A decent socket cap screw would work as you say. I often make tools from 12.9 socket caps. I once made a brake lever pivot for an old Triumph TR6 from one, milled the square in the end and used the milled square as a makeshift broach to cut a new square in the actuating arm slightly bigger than the original. Worked great.
A 10mm shank socket cap is almost perfect diameter for a 7mm square to be milled, the across-corners dimension being 9.9mm
|Thread: Anybody familiar with OZ25 collets?|
Oz25 collets are also known as DIN 6388. The clamping range is +0/-0.5mm from the marked diameter. Normally, they are etched on the narrow part of the front face.
If you made a cap for the non-cutting end of the broach with a small bearing in it. Put the part in the lathe chuck then dialled in some off-set on the tailstock you could probably push it through using an old dead centre in the tailstock.
Edited By Pete Rimmer on 08/12/2019 11:35:40
|Thread: 3D printer recommendations|
I can totally understand that, but people do what they are comfortable with. I saw nothing more than a cold joint that takes 3 minutes to re-solder so I wasn't about to un-do several hours assembling work, pack it all up into the original bags and send the whole unit away for the want of a few minute's simple soldering. These things are modular produced so a cold joint wouldn't be indicative of the quality of the other parts, which I have to say is very good.
I just took delivery of one of these today - a Creality Ender 3 Pro. I got it from Amazon which means I paid a bit more than the cheapest UK prices (and a lot more than the bangood ones) but you get it next day and don't have to worry about fedex dropping a bill for import,vat and admin fee six weeks later.
Anyway, I'll recount my observations here:
Packing: superb. You get literally everything you need including tools all packed in a 2-layer box with properly shaped foam inserts
Build instructions: adequate. There's a sheet and there's also a PDF on the supplied SD card & reader. It's all pictographic and there is no easy way to get it wrong.
Construction: Better than expected. I put mine together loosely leaving all screws that could be tightened later just snugged up.There's only the two vertical rails, top strut and x-axis bar really plus a load of fittings. The guide wheels were well adjusted and all I had to do was get out a square to check things before tightening. Once fully assembled the frame is impressively rigid for what it is. I suspect that most people just throw it together but I am a little more picky than most and don't want to do it twice or try to dial out any mis-alignment.
Assembly: Straightforward but I did find a couple of small adjustments I had to make notably the z-axis motor mount and the cable routing. I also found that the pre-fitted cables didn't lend themselves well to following a natural route so I removed the bottom cover, cut all the zip ties, ran them out straight then routed them in nice relaxed curves to their destinations before tying them back up again. The z-axis motor simply couldn't be fitted to allow the screw to run parallel to the axis of travel so I opened up the two holes a little to allow some adjustment and made a small packing gasket from the card box that they put the filament cutter in to space it off the column, and doing this made the screw run nice and true. Not serious but looking online it seem it's an endemic problem that would take no effort for them to sort.
Operation: Well, the first time I turned it on it did - nothing. The 24v power lead had come out of the 2-pin plug due to poor soldering. I had to remove that and re-solder the lead. After that it turned straight on and worked well.
One thing I will say is that the operating instructions are sparse. There are a lot of configuration settings (that you could mostly leave alone) but they simply aren't covered in the instructions. Thankfully, the online support is huge and you'll easily find out what does what and that's what I had to do, as I literally know NOTHING about 3d printing except what I've learned in the last 10 hrs.
I printed some test prints to prove the bed levelling was good. I found that the bed plate was not truly flat but apparently that's because it was cold and they flatten out when heated. I also found that the default heat of 45 degrees for the bed and 195 for the nozzle were too low for the PLA and the tests prints were not sticking. I turned them both up 10 degrees and the alignment tests came out great so I kicked off a test print from the card.
A quick note about the software side which (like me) you might not realise:
I use sketchup but no other 3d software so I was planning to install fusion 360. Can't do that on my old PC as it needs 64 bit. Also I was going to use Cura slicer - can't do that either as the 32 bit version is very old. Creality do however bundle their own slicing software on the SD card (and it's downloadable) which does work even on older pc's so a bonus point for them there. I also discovered that you can export sketchup files to a .due format that their slicer can handle, so I'm going to try that tomorrow.
On the whole, am I pleased? Well yes I am very happy. I didn't expect it to be quite so good for a £200-ish machine. I'm going to cut my teeth by printing out some of the many parts that people have made for the printer - cable guides, tool tray, small clips etc then I have a list of other things I want to print of my on design. I can see this machine getting a lot of use. Certainly I'd recommend one to even a raw novice like me.
Do you have a pillar drill or milling machine Derek? You can make a basic broach driver using some scrap stock and a ball bearing. Simply drill an off-set counterbore in the stock and load it in your drill/mill then make a similar one for the broach but with the hole central, and put the ball bearing between them with some grease for lube. I've broached a couple of things like this.
Edited By Pete Rimmer on 07/12/2019 14:15:36
|Thread: Meddings Pillar Drill, VFD and referb|
Internet diagnosis is always difficult because of things like that. Difficult anyway. For instance, the small portion of windings visible in the photo look like they have been somewhat cooked, but that might be another trick of the light or even just the colour of the varnish.
Star or delta connection should not have a bearing on the fault you were getting, but I see evidence of burning to the right of the connector block. I don't think that you can safely assume that this fault is fixed.
|Thread: Lathe lighting|
Well, light isn't like coolant it doesn't have to follow the work. If you fix the lamp somewhere where it lights the whole area around the chuck you'll get better spread and less glare. If the lamp is moving you might have it so low that you feed it into the work, the chuck or it might get caught by any stringy swarf and whipped into the job (or the operator). It's also in an inconvenient place for the compound controls as you've discovered.
I see no good reason to have it moving with the carriage, and several reasons not to. I'd re-locate it to the splash guard so it can be swung out of the way at times.
|Thread: Ho hum it's a cracker, but not in a good way!|
I wouldn't worry about the crack but that slide certainly could do with a bit of scraping.
|Thread: Why mostly manual cars in UK|
Autos have traditionally been expensive and juicy and carried the stigma of being a car for people who 'can't walk and chew gum' i.e. can't manage a clutch and gear stick. I say this having a mother who somehow managed to pass her auto test but even in an automatic being her passenger was a terrifying ordeal.
I don't know how it is in Aus but in the UK if you'll normally learn to drive in a manual car which gets you a licence to drive any transmission type, or you can opt (either by choice or necessity as above) to take a test in an automatic which restricts you to automatic transmission cars. Thus, most people test in a manual car and therefore buy the type they learned to drive in.
The reliabiliy/consumption issues are largely gone now and the 'stigma' much diminished but manuals are still (just) out-selling autos, which are fast gaining favour because of modern technological features such a paddle-shift. Kids play driving games on their consoles and that makes paddle-shift (and pure-auto) cars very familiar to them now.
|Thread: Screwcutting on the lathe|
Iain I've done a little drawing in cad today and your 0.92mm infeed at 30 degrees comes up slightly short of the minimum depth you'd need to reach the minor diameter for the nut so it would never go on, and it would require a 0.4mm flat to attain the proper flank width at that depth anyway. Obviously you don't want that because your thread is 1. not quite deep enough and 2. has no root clearance.
If your tip width was 0.25mm (10 thou) you could infeed 1.06mm and you would have a usable thread with good root clearance.
With a sharp point you need 1.31mm infeed, at 30 degrees to achieve the proper thread width at the pitch line. This is not very desirable because the sharp point makes for a much weaker thread.
Edited By Pete Rimmer on 04/12/2019 11:51:13
|Thread: Kerry 1124 lathe - some healing required|
I would repair that gib adjuster by counter-boring the adjuster hole deeper and making a new adjuster screw, trim the end of the gib to suit.
|Thread: Screwcutting on the lathe|
HSS ground tool? Most probably you don't have the proper tip radius/width which means you are 'touching off' the start of the thread too far out, meaning you are stopping before the thread is fully cut.
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