Member postings for John Baron

Hi Guys,

This picture contains all the data required to design what ever size Kant type clamp you may want to make.

Note that the size is based on two concentric circles, all the holes bar one fall on a circle. The symmetry makes designing your own easy. The dimensions on this drawing are the ones that I used to make 100 mm clamps.

I had my four pairs of frames laser cut from 3 mm plate for the sum of £10.00.

Hi Lynne,

I tend to replace the keyless chucks with quite cheap 1/2" keyed ones, mainly because the battery drills seem to use 10 mm capacity chucks that are quite poor and often or not I need to use a bigger drill. The ones I've bought are usually sold with an arbour intended for SDS drills. They are the same thread as the keyless ones and just screw straight on. Just beware though there is a left hand screw in the middle of the jaws, that you have to remove first and then replace when you have swapped the chuck.

I've probably eight or so spare keyless 10 mm drill chucks. One of them is only 8 mm !

Hi Guys,

I used to use a length of all thread bar and clamp work or jigs to the drill table, much in the same way as clamping work down on the mill table. Nowadays I have an X-Y table on the press drill with "T" slots and use the same technique for clamping work down.

Hi Brian, Guys,

I've used a lot of M6 left and right hand all thread for lead screws on several items ! The 1 mm pitch and a graduated dial with 40 index marks on a 50 mm diameter dial varies less than one index mark in 40 turns, so I would say that the error is negligible.

Hi Blowlamp,

Thankyou for that link ! I'll have a play with that.

Hi Guys,

If you want some very cheap or even free HSS blanks, have a word with your local scrap yard ! I've picked up a lot of HSS and carbide tool steel that way. Some has been very odd sizes, many already being ground to shape just needing touching up.

A major problem for me is that there is no Linux version of CamBam ! Where as Qcad with the Cam module does support Linux. Having said that I do use Qcad regularly, and I have played with the Cam part but don't actually use it in anger, not having any CNC machines.

Hi Nigel, Guys,

My comment was aimed at conventional induction motors, having field coils wound on an iron former that directly conducts any heat into the motor body. Since the DC motors used on these mills use ferrite magnets to provide the field and don't generate any heat. Any heat from the armature can only escape via the bearings supporting the armature.

The rather puny fan inside barely moves any air to cool the armature, even at full speed.

Hi Ian,

I have a similar mill, a Chinese "Optimum BF20LB" mill. I've repaired the motor on several occasions ! I made and replaced the gears with steel ones because the plastic ones stripped the teeth, and it was more cost effective to replace them. Actually the gears stripped whilst using a slitting saw on aluminium, the work got hot and grabbed the blade stripping the teeth off the gears.

I do have a 3 phase motor to replace the DC one and have made some parts to mount it, however a ducted cooling fan mounted on top of the existing motor seems to have much reduced the heat that is created. The major problem with the heating of the motor is simply that the only way that the armature can get rid of the heat is through the bearings. There are no field coils to conduct the heat into the motor body !

The brushes and brush holders suffer badly because of it. Also the push on tags don't make a good electrical connection so they get hot and the resistance increases causing them to get even hotter. I've thoroughly cleaned and soldered the tags to the brush holder terminals. This removes the major cause of brush holder failure due to heating.

The motor still gets very warm but nowhere near as much.

Edited By John Baron on 08/11/2021 19:50:36

Hi Guys,

My FOBCO uses an A56 belt ! I got mine from Motorsave, about £7.00p a couple of years ago.

Hi Guys,

I use a "Shear" tool particularly when I want a good finish for a bearing fit !

The only problem is that you can only take about a thou DOC without destroying the tool edge. The swarf comes off like a very fine spider web.

Hi Guys,

A maximum 80% fill is the recommended level ! At least for LPG.

Hi John, Guys,

Try an old computer case panel !

Hi Duncan, Thankyou for your comments.

I called this a left hand cutter because if it were in a lathe looking down at it, the tool cutting edge would be on the left side !

But I'm probably wrong to call it that, after going and looking at some lathe tool pictures. It seems that handedness is as viewed from the front rather than down from the top. But I can't go back and edit my post to correct it.

Hi Guys,

No I've never seen ones like mine for sale either ! Probably because they are too easy to make, primarily a simple turning job, with a press fitted shaft, and with only a single tapped hole for an M6 grub screw and a simple drilled hole for the cutting bit. Obviously the shaft and the disc have to be square to each other.

After turning the shaft and pressing it in, I faced the disc whilst holding the shaft in the lathe chuck. This ensures that there will not be any wobble and the whole lot will be concentric. The hole for the tool bit was drilled and the grubscrew hole drilled and tapped before pressing the shaft in place.

I use short pieces of 1/4" inch square HSS tool steel, though I did have a small piece of 8 mm round carbide rod that I put a cutting edge onto and tried.

The original idea was to take advantage of the flywheel effect and making the shaft and disc out of 20 mm thick material offers both rigidity and balance ! I can spin this fly cutter as fast as the mill will go, just over 2650 rpm without any detectable vibration, which you can't do with the conventional angled cutter types.

It also reduces the edge hammer that you get with narrow work and large DOC.

In use I tend to run at around 250/300 rpm and 20 thou DOC in steel. The actual cutting face has the same rounded corner as a lathe tool but the cutting face is about 2 mm wide. I do this so that it reduces the tram lines that you get if the feed rate moves the work forward before the next cutter sweep.

In the picture the cutter has a round edge, I no longer use this shape ! While it works it produces a high spindle loading and looses its edge very rapidly. A more left hand lathe tool shape is much better and actually easier to sharpen.

This is my go to fly cutter !

As far as the cutter is concerned it is treated as though it was a left hand lathe tool. Its on a 20 mm shaft and the disc is 20 mm thick. Depending upon material and spindle speed I can hog mild steel off with a 0.5 mm DOC, 1 mm in aluminium. I recently tried a carbide cutter and whilst I could up the spindle speed the surface finish was little different from the HSS cutter I use.

I won't go into the pros of this cutter unless anybody asks.

Hi Robin,

I cut my glass scales using the bandsaw, 14 tooth blade, without any issues. The trick is to pack the glass scale inside the extrusion so that it cannot move. I used paper towel damped with water and packed it as tight as I could. The bandsaw cut it easily with only very slight chipping of the edge of the glass. I removed the paper packing with a dental pick.

Good Luck.

As can be seen in this picture the chipping was only slight !

Edited By John Baron on 19/09/2021 10:27:14

No ! The tower base and 8 ft support post is all that is left. The actual tower was scrapped some time ago.

I have some people coming to cut the gusset plates away ! They are aware that its galvanised and said that its not a problem.

Thanks for the advice guys, its appreciated !

Hi Guys,

This is a drawing of mine ! I made it to specifically adjust the cutter. The nice thing is that once used its easy to set the cutter to increase the depth accurately.

It was designed for a upto 20 mm diameter boring bar. It works quite well on a smaller diameter bar as well. Otherwise just adjust dimensions to suit your bar.

Thanks Guys,

Some good advice there ! Fortunately I only want to remove one of the four gussets, though removing the front two would be an advantage in giving me a clear area. The rear two gussets can be left alone since there are large water storage tanks on either side catching rain water off the building roofs. The column is being used to support the wife's washing line, so woe betide me if I disturbed it.

I'm going to make enquiries at a tool hire place in town and see if they have anything that can help !