Member postings for Rod Renshaw

Thanks to those who responded to my question about angle blocks.

I was just curious really. I do have a few angle blocks but I don't have enough blocks or use them often enough to need to have a spreadsheet or other aid to get any particular angle.

Rod

Interesting thread, far beyond my IT knowledge.

Can anything similar be done for sets of angle blocks where each block ( in a stack of blocks ) can be used one way around to add to the total angle or the other way around to reduce the total angle?

Rod

Jack. Thanks for the link, but unless I am missing something, that's a coping saw frame of traditional type. I woild like a frame which will hold a much finer blade.

Frank, that's a wonderful frame in that video. I don't need one either but if I had the space and the money....

The video also reminded me why I don't use the traditonal fretsaw frame so much. I have found that the very deep frame ( 15" ? ) is just not rigid enough to get enough tension on the blade for accurate work, Hence the wish for a shallower frame (More rigid) with at least some degree of rotation of the blade.

Clearly there is room for different opinions on this, as in many tool and engineering matters!

Rod

Edited By Rod Renshaw on 02/08/2023 16:33:34

I agree that a full 360* is not vital but some degree of rotation would be very useful when dovetailing boards which are wider than the throat of the piercing saw frame, to be able to slide down the vertical cuts and then turn along the bottom to cut out most of the waste. I do have an old fashioned fretsaw frame with a deep throat which I could bring back into use.

I have not thought of using spiral piercing saw blades, has anyone used them? How wide is the kerf?

Having said all that, the Japanese don't use a saw at all on the waste and just use a chisel - but then most of their timber is not very hard.

the chap in the video is, I think, David Barron, wno makes or perhaps made a very effective magnetic jig for guiding the Japanese saws.

Rod

Edited By Rod Renshaw on 02/08/2023 13:35:14

+1 for using Japanese saws for dovetails. It's the contrast betwwen the thin, straight, spelchless "perfect" kerf left by the Japanese saw and the wide, rough kerf left by the coping saw that makes me yearn for a fretsaw frame with 360* rotation.

Rod

The Yorkshire Post reports that the Ferrybridge motorway service area has installed 12 new ultra-fast EV chargers. But then discovered that the power supply to the service area can't cope, so thay have installed a diesel generator to power 6 of the EV chargers until the cable supply frmo the grid can be improved.The other 6 chargers bring unused. Whatever next?

Rod

Edited By Rod Renshaw on 02/08/2023 10:19:04

Coping saw frames usually allow 360* rotation of the blade and this is often useful for such jobs as cutting out the waste from dovetail joints. But the blade is very coarse compared to a fretsaw blade.

For finer and more delicate work, including watch and clockwork, most fretsaw and piercing saw frames do not allow any rotation of the blade at all, so the frame shown in the OP is a distinct improvement and if one were using it all day long then the lighter weight might be helpful. Whether it's worth the money is a matter of opinion.. Fret and piercing saw blades are both held by clamps and are interchangable, but a coping saw blade is pinned and so is not interchangable with the first two, I have sometimes thought of trying to make a fret /piercing saw frame with 360* rotation but not tried it so far.

Rod

if you have oxy-acetylene gear you can melt the end of a Stellite lathe tool blank and "drip" molten Stellite onto the end of the rod, which can be of any steel, and get a very hard but just about polishable surface. I have never done this myself but I have seen it done on a commercial diesel repair, and which engine went back into service without apparent problem.

Agreed, so this will only fit properly on one or the other, or perhaps neither.

Rod

Edited By Rod Renshaw on 16/07/2023 14:26:38

Mattthew, + 1 for the (corrected ) advice above. It seems farirly clear your father modified the change wheel layout , probably to cut metric threads as suggested by Pete above.

If you rearrange the change wheels as in the advice above or in your handbook, then all should be well. there is almost no chance of a fault in the gearbox itself, it's just a matter of arranging the right wheels into the right order. The wheels are designed to be able to be rearranged to enable the lathe to cut a wide range of threads.

The late LBSC used to mention "Treblet " tube in some of his writings. This was a type of brass tube which he thought had been passed through dies 3 times to give a better than usual and more accurate finish, both inside and out. He mentions using it for boiler feed pump barrels and steam whistles, and says that one size fitted nicely inside the next size up. I wonder if this was the type of tube used for the original engine design.

Rod

Dave

Thanks for the suggested type of wattmeter. For some reason, perhaps influenced by the posts above, I had thought it would be more complicated and expensive than that. I will get one and see how much power things actually use.

Rod

I had thought I understood some of this but clearly I don't understand enough. Can anyone suggest what type of "wattmeter" I could get which would read "real "watts on AC mains circuits. I don't need an expensive professional standard thing just something to give me an idea of consumption.

Thanks

Rod

UP with which we should not put?

I would be tempted to just turn down the register and leave the rest at the full diameter. The remaining backplate should act as a flywheel and improve the finish when turning, and be especially helpful when doing interupted cuts.

I am not sure I entirely agree with Mike about twist in lathes

I agree a properly made lathe bed should be free of twist as it leaves the grinder but the story does not end there. The manufacturer then typically hangs weights ( gearbox on the front and motor on the back etc ) on the bed to make a complete lathe. This can introduce twist in what are really quite flexible castings, and this twist has to be removed by the process we generally call levelling to produce a lathe that will turn parallel.

There seems to be no essential need to make the lathe literally "level" but it is very convenient if one needs to use attachments like milling slides. If the lathe is only ever used for simple turning there is much less need for it to be level but any twist still needs removing.

Rod

All good ideas.

If only a few pieces are needed, an alternative plan would be to mill a 5 mm slot from one of the boundaries of the workpiece and then silver solder in a 5 mm wide piece of mild steel leaving a 5 mm square hole, as George Thomas did when making a square hole to align number punches on his staking tool. Do the hole first then clean up the outside of the workpiece to get an almost invisible finish.

Rod

An alternative idea might be to mill a 5 mm slot from one of the boundaries of the workpiece and then silver solder in a 5 mm thick piece of mild steel leaving a 5 m square hole, rather as George Thomas did to make a square hole for aligning number punches when making his staking tool,

Rod

Yes, it could have been so. I thought I had read it in the newspaper.

I remembered the content but not where I had read it.

Rod

I read a suggestion recently that some of these scam messages have deliberately poor spelling and grammar so that educated people will recognise the messages as scams and not respond. Those who are not so educated may respond and, being less alert, may get sucked into the scam. It is, so the thinking goes, a way of getting the people who are contacted to self-select so that only those who might not be so aware of the dangers will respond.

Rod