Member postings for Tony Ray

Mines 120956 so also pretty close!

Oh come on Dave you can’t mention a 10M without posting any pics!

Hi Gareth,

A power feed is a great idea, I did this on my SX3. I'm not familiar with your mill - is the leadscrew currently un supported at what will become the power feed end? If so could you not drill,bore,ream that end and fit an extension ? a good fit, Loctite and a cross pin will get you there. It won't increase your travel but do bear in mind that at the extreme of travel the table won't be supported much.

Alternatively you could as Ketan at Arc if the same leadscrew is use in a larger model and adapt it.

Making a leadscrew of that length, pitch and diameter is quite an undertaking as there will be a lot of flex and a trapezoidal profile puts more load on the machine. Longest I have made is ~300mm and that was 22mm in dia. so flex wasn't an issue.

There are companies that would make one for you but I suspect it might cost North of £500 maybe a lot more.

To be clear I never said anything about drilling holes in the wheel. Drilling results in a series of dimples. It is well explained on YouTube by respected machinists. I agree that a balancing hub would be preferable, if anyone has a design for the Kennet or Quorn I’d be interested to see it.

It should also be noted that a wheel can be in balance but out of round.. There is no point in balancing  a wheel that is out of round it needs to be trued first and this will also improve balance.  Unless there is a balance weight arrangement the wheel will need to be drilled to remove imbalance, that’s not something I have tried and it makes me nervous thinking about it, although the wheels I have are pretty thick at the  base of the cup where the drilling would take place. Rotating the mounted wheel by hand with a reference pointer will show how far out of round it is before firing it up to dress. I heavily dressed the cutting face to get that true and the first  20mm or so of the outside cup and a bit on the inside to improve matters. I had to be  creative to come up with a way of doing this with a bit of square bar with a single point diamond dresser at 90 degrees slid along a fence mounted to the table guard removed. Imbalance will cause bearing wear over time and will shake the setup but I believe that the risk of a ring tested new wheel exploding during this initial balancing and truing is low and should not cause bearing damage. I use a 1 thou DTI on a mag base to measure carriage movement and when balance is bad it’s unreadable due to needle movement.

The other thing to mention is the two cup wheels I bought are both 6mm or so deeper than the wheel guard which I think is a Quorn item.

Edited By Tony Ray on 29/07/2023 08:19:57

I also bought a Tyrolit cup wheel - it was no better. In terms of concern ntrcity or balance. The Chinese diamond wheels are better but aren’t the best choice for HSS.

Hi Jerry,

Welcome to the Kennet club. As this is built from kit may find all sorts of things have been tailored to suit the makers requirements. I use 5mm dia. Belting I have the texture variety but I don’t thinks there’s much to choose between that & the smooth. I bought a 100mm cup wheel from Midland’s off flea bay. Do be prepared for a lot of run out on the wheel I had to dress a lot off to get it running in better balance. It wasn’t a case of the wheel not being mounted wheel the wheel itself wasn’t round. I have spent a fair bit of time creating dust shields and aprons to reduce the amount of grit entering the slides and the tilt & rise and fall mechanisms as it was driving me nuts. If you haven’t got an Er collet holder for it Er25 is a worthwhile addition.

Tony

Hi Laura,

I'm sorry for your loss.

You have several options

1. Contact a dealer

You will not get the best price for it but as long as you state that it all has to go you will be clear of it in one hit.

2. Try selling it on this forum, a well known auction site - or another related well known free site and there one other free site that you'll find if you search for home workshop ads

This is possible but it will take time and you have the difficulty of identifying what is what in order to help sell it and price it accordingly.

3. I believe the Society of Model & Experimental Engineers SMEE offer (or used to) a clearance service - I believe there's a fee or %age of sales but at least the tools will go to like minded people. [email protected]

4. Find someone local to help you - did he have any like minded friends?

Hope this helps

Tony

Thanks Bill, I knew the screw should be about 0.155” and being a metric man I didn’t see the error. I do however need magnification to see what’s going on when cutting threads at that diameter. My Dad showed me a very fine fusee chain and told me they were made by children as they could see what they were doing.

Ok I couldn’t wait until tomorrow. I just ran a 3BA die over my best attempt a 40 TPI Whitworth approximation and it just removed a little material but it’s made a substantial improvement to the feel. Luckily the die is split so I can adjust the fit. I suppose the statement an out the high cost of spares for the CHS is based on the lack of readily available info on what is required.

Thanks everyone, sorry I missed the BA listings Inthink the chart I have is similar but missing that info. I have a fair range of BA taps & dies, my Dad a watchmaker, spent the last part of his career in instrument making, I know iI have 3BA taps not sure about dies. I agree it would be easier to buy them. Anyway I’ll have a look tomorrow.

Hi Bernard,

Thanks appreciate the help, its all a bit odd, had it not been hardened I would probably have re threaded them by now. I suggested wer as everything I have cut thus far tightens up the deeper the thread is wound in, hothing I have tried thus far seems 'right'.

Thanks Peak, I use this as my starting point, a real nusiance that they don't quote TPI.

Can anyone assist with some thread dimensions for the 4 off front plate retaining screws please?

This is the early type with non-standard screws and whislt I have sucessfully made the scroll retaining screws 0.155" x 48 TPI and the +/- adjuster 36tpi, I just can't work out what TPI the 0.155" dia retaining plate screws should be. I have tried 36, 48 and now 40 TPI. I have assumed that whatever it is is 55 degree due to the age of the head.

If someone is able to measure the O/D and TPI of an existing screw that would be a great help. In addtion can anyone offer advice on the correct tip width and thread depth for a nominall 0.155" Whitworh form ? It seems that the thread depth of 0.640327p and a radius of 0.137329p where p is the pitch. isn't working out for me I'm taking the calculation to be

0.640327 * (1000/40) = 25 i.e. 0.025" or 0.635mm single depth of thread and the radius to be 0.137329 * (1000/40) = 3.43 or 6.86" (0.14mm) across the dia.

I'm working on the basis that is the tip is a little narrow I'll need to dept a little more but trial so far are leaving a razor sharp crest if I depth anywhere above 0.022"

Matters are helped by havein no screw to work from and the threaded holes being so narrow and seemingly worn . I know I can buy them form eg Wiseman (cost as yet unknown) but as I need to make the front plate in for a penny ...

Thanks

What is working for me is focussing on improvements to how I do things. Eg making tools, & storage solutions to improve my efficiency, these projects don’t take long maybe a day or two so I get a quick return for my efforts.

I usually work on 120% of the stated motor rpm which would be 1680 rpm which is'nt too far away so you can probably run it @ 1800. Assuming your chosen motor is rated for VFD use - old motors don't much like VFD's and can let out magic smoke if the insulation breaks down.

Where is the 3000 rpm coming from ? You won't get that by overspeeding the 1400rpm unit. Do also bear in mind that your roundhead won't have been designed to cope with 3000 rpm and more importantly you'll need to ensure that any chuck you fit is rated for it.

Don't be fooled by the idea that a VFD is the answer to all your speed needs - there is no substitute for using the gearbox and any pulley systems to get the rpm (and torque) you need. I have a VFD on my Harrison M250 I only use the variaible speed @ 6Hz for clocking in otherwise it's just there to drive the 3 ph motor.

Tony

I understand the need for a break and you can tweak the gibs to suit whatever part of the height range you are using.

Oiling these old machines, in fact any machine seems to me much harder than it needs to be. I have machines that have nipples that it looks like they are made for grease gun attachment ( but require oil), some that look like a nipple some that are the flat ball oilers. I dislike all of them I have recently put a piece or 6mm id PVC tubing on the end of an oil can; that has helped greatly with the second type and I expect it to work on the grease nipples type as well.

If you have room I would look at fitting lidded oil cups where you can, that's a job that I need to get around to myself.

Can I ask why single point thread cutting is going to cost you money ?

The absence of your straight edge is bothersome.. What length did you say the column dovetail is? At least you’ll be working on a narrower surface so metal removal will go faster. I think the knee ways are poorly designed, that’s why they have worn excessively. I would suggest putting in some oil grooves on the moving knee surface ( less work than doing the column like diagonal zig zags. Those grooves should stop before the ends and I would install way wipers at least on the top side; you can make them out of the felt you’ll need for the lozenges.

That’s not a bad idea, you may be pleasantly surprised how good it is without that last bit of work.

Hi Mark,

I adapted one of these.**LINK**

but I paid £30 for it. I copied Lookcreations on the tube. The worm drive that provides the speed reduction to the whetstone is really poor so I would not go down this route again. Instead I would copy Stefan Gotteswinter and us a 24v dc geared motor, there is lots of choice on eBay. DC motor speed controllers are also readily available if needed.