Member postings for Hopper

For anyone who does not have a vice with those handy slots in the base already, here is one way of milling them yourself.

Clamp a length of square bar to the milling table, set with a dial indicator to be dead true to the travel of the table and the T slots.

Flip your vice upside down and clamp the jaws onto the square bar.

Mill slot in base the same width as your T slots.

Fit pieces of T-slot width key-steel into slot and secure with screws into holes drilled and tapped into the vice base.

Alternatively, set your vice up semi-permanently on one end of the milling table and leave it there. This leaves the rest of the table for other use such as rotary table, direct clamping etc. Works best on larger mills I suppose.

I think if it has the Starrett name on it and you are buying it from the Amazon Starrett shop (so you know it's not a knock-off), there is very little chance it will be no good. It may not be inspection grade made to be used all day every day for the next 20 years at high levels of accuracy, but it is pretty sure to fill the need in the home workshop.

There have been a couple of threads in recent months on parallel motion links on beam engines, going into the geometry at some depth. The Google search halfway down the forum homepage should find them.

But I believe you are right in thinking the links need to be the same length.

Starrett is indeed a good brand. And that is a very good price for a Starrett dial indicator. I see they list others in their Amazon store for hundreds of Pounds. So that is obviously their budget model. Might pay to do some research and find out what the difference in specs is. I should think it would be ok for home hobby use though. I have had good use from Chinese cheapies over the years so am no connoisseur.

How heavy are the "heavy metal objects" you will be putting on the bench? Your design with 5mm plate would be OK for most model engineering and say motorcycle engine rebuilding and that kind of medium duty work. But not so much for rebuilding bulldozer engines and the like or even maybe a full 7-1/2" gauge locomotive model.

I would add some braces to the legs for sure though. Either around the legs near the bottom, or diagonal braces near the top of each leg going to the main frame under the bench top.

If you weld the frame up good and solid, you should be able to attach the 5mm sheet to the top with small tack welds in multiple places without unacceptable distortion if you go carefully. It will not be a dead-flat surface table but should be ok for a general work bench. Bolting it with countersunk screws is a good idea if you want to be sure of dead flat. But it will only be as flat as the frame you make underneath of course.

Edited By Hopper on 13/03/2023 06:46:59

Bit like a cross between dismantling and reassembling a house and a car. I would not go there.

Couple of cheap self-assemble garden sheds from the hardware store might be better.

If it is just minor scratches, use the old motorcycle show trick and fill them in with felt pen of the matching colour. The permanent marker ink is surprisingly long-lasting.

Aye, good job. Or you soon would be, by the sound of it!

Loose fit of the wheels on their spindles is ok. Stops them jamming up and any slack is taken up by the force on the wheels. I have the same problem with the knurled adjuster knob on my knurling tool too. I think there is a T-bar in its future as my hands are unlikely to get any better at this stage. Looks like you could drill a hole through yours and insert a bit of silver steel rod as a T bar for easier leverage.

Play around with it on some scrap trying the things suggested in posts above and you will get a method worked out that suits you and your equipment I am sure.

Re the skewing comments above, I have had trouble with the Myford toolpost rotating under pressure sometimes. But if you nip it good and tight and take care to set the knurling wheels as close as you can to the 12 and 6 o'clock positions on the job, it should stay put.

PS One thing to note in the Joe Pie video above is his warning to be VERY careful about putting anything near the knurl and knurl wheel contact point under power. Fingers, brushes, oil can nozzles, rags, whatever, will get sucked in between the knurl wheel and the job and nothing  will stop it until it comes out the other side. Don't ask me how I know this! (Luckily it was a brush and not my finger. But it cured me of the habit of feeling how sharp the points on my knurling were while the job was still in progress. )

Edited By Hopper on 11/03/2023 09:47:43

Edited By Hopper on 11/03/2023 09:56:10

Posted by Roderick Jenkins on 10/03/2023 21:42:46:

It took a bit of fiddling about, the timing is still not quite right, it's blowing back a bit through the carb but, hey, it goes

Rod

Edited By Roderick Jenkins on 10/03/2023 21:43:29

Chuffs away very nicely. Well done!

Based on full sized Harley V-twin experience, spitting back though the carb is most likely lean mixture.

Spark timing too retarded can also cause it due to weirdness associated with the "waste spark" that fires on the exhaust stroke on the other cylinder, but 45 degrees late due to the cylinder spacing -- so can end up sparking at or a bit after TDC as the intake stroke is starting. If there is enough mixture in there already it can cause a hiccup. (Technically known as a "carb fart".) Not sure if this attribute of a full sized V-twin with one carb transfers down to model scale but may be something to fiddle with and see.

Just had one in the shed this morning. Wiring a tail-light onto a motorbike I used a male and female bullet connector, those horrible crimp on ones from the auto parts store. I hate the look of those squashed plastic connectors so decided to put a bit of heat shrink over the plastic sleeve on the female fitting to hide it. Hit it with the heat gun and promptly shrunk the heat shrink tube AND the plastic surrounding the metal fitting inside. So bad that the male fitting would not go in, even after a bit of "rework" with a screwdriver to open the plastic up a bit. Cut the whole mess off and did it again, without heat shrink.

So I won't do that again and must order some more proper solder-on fittings or the crimp on ones that use the special pliers and then you slip the sleeve on afterwards.

This is the one I made, from drawings found I dont remember where on the internet but I think it is the same as the one in MEW issue 72. Those 3mm thick flat side plates stop the arms flexing or wandering, and also form the main frame of the tool so it is very simple to make. I have been very happy with it.

The cheap Chinese knurling wheels i used seem to be very good.

I've had good luck buying used machine reamers off eBay, old UK and Australian made ones. And if you can work in metric, whole sets of new Chinese "chucking reamers" are available amazingly cheaply and seem to work well enough for the home workshop. Well worth building up a collection.

Or you can use a redneck hone for finishing bores. A length of wooden dowel with a hacksaw slot in the end with a strip of emery paper wrapped around it, fed by hand into the hole as it is spun in the lathe. Or held in a pistol drill and used like a brake cylinder hone. Sounds bodgy but works quite well.

I am sure your bearings will work fine as is though. They look pretty nice in the pics, and pics tend to make such things look worse rather than better.

Edited By Hopper on 10/03/2023 23:17:35

I vaguely remember being drilled, and drilled, and drilled, on "mental arithmetic" at school, which included adding and subtracting fractions and the like. So in those days every schoolboy and girl must have been able to instantly recognise how many 16ths in the 1/8 and the 3/4 and add them to the 7/16 without any drama. I struggle to do it now though. I blame years of working in metric for that.

If you want smoother on future jobs, try reaming the holes in the bearings for a smoother finish and use emery cloth to get the final smooth finish on the shaft. This gives you very fine control over the final shaft size for clearance too.

I always start the knurling with the wheels sticking out half off the job at one end and then move the carriage slowly along and back and add the extra pressure on the knurling wheels with them hanging half off the job again. Seems to help avoid the double knurling trouble. Don't let the wheels disengage from the job once started.

I also made my own knurling tool with flat plates on either side to hold the arms in place and in line. Found the drawings on the net somewhere. It is similar to the Hemingway Kits one.

Are you knurling at slow speed? I always use backgear, about 90rpm or less. And plenty of oil on the job constantly.

It also helps to take a skim cut over the job before knurling to make sure the surface is running nice and smooth and true.

Try some practice knurling on some bits of scrap mild steel. It can take a few goes to get the hang of it.

Edited By Hopper on 10/03/2023 21:18:17

I have used Trefolex on machine reamers for as long as I can remember. I think we were taught that as apprentices.

That sounds like a good idea. Alarms and CCTV work well too. But cost money of course, although getting cheaper for the DIY systems these days.

Yes, when I get to thinking, I could write a book...

Welcome to the forum.

Choice of mill depends a bit on what size work you want to do on it. The Seig SX3 is a popular choice for general work. It;s smaller brother the SX2 is equally popular with those who do smaller work.

Round column mills come with the disadvantage of losing alignment when you have to move the head up and down for tool changes. Combo lathe/mills are notorious for almost doing everything but not quite getting there due to compromises that have to be made.

Edited By Hopper on 09/03/2023 12:38:17