Here is a list of all the postings ken king, King Design has made in our forums. Click on a thread name to jump to the thread.
|Thread: What did you do today (2015)|
I expect you all spotted my small oops when quoting Martin Evans' tolerance on a nominal .156 hole. The figures should have been - larger side .1559, smaller side .155 Sorry about that.
Not a 'Today' activity, strictly speaking, but only a couple of days ago, so near enough I reckon. I finished and posted these four Eccentric Connector Rods to a client who is building a 5" gauge model of a GWR 28XX 2-8-0 .
The drawing, by Martin Evans, calls for the clevis holes (nominally .156", 5/32" to be .1599 on one side and .155 on the other !! The best I could do to satisfy this requirement, for press fitting pins, was to make a test bar accordingly, then use the lead-in of a hand reamer to achieve the nearest agreement. In practice, it worked out pretty well, the tiny taper in the holes being immeasurable.
The coins are to add scale only and are not representative of the value ! My brother-in-law tells me he used to see these locomotives regularly at Oxford, heading long freight trains. He remembers that they had very open cabs, some having been built back in 1910, and that in inclement weather there was often a tarpaulin pulled across to give the men on the footplate a little more protection from the elements.
|Thread: Granite surface table for £6.99|
Shopping in Aldi's his afternoon and happened upon black or grey granite 'Worktop Protectors', to allow placement of hot pans on vulnerable work surfaces. There are two deals available, both priced £6.99. One (which I purchased) is a single granite slab measuring 400mm x 300mm, the other comprises two slabs, each 300mm x 200mm. The slabs are about 15mm thick so are substantial, but the most valuable aspect, from a non-culinary point of view, is that they are ground to optical flatness and so make jolly inexpensive surface tables for marking out, checking and measuring on. I checked the flatness by looking at a reflected fluorescent tube whilst tilting my slab this way and that, without detecting any ripple or distortion. I reckon that means the surface is adequate for most folks need, SO .. if you're lacking such an item in your workshop go and bag one quick; stocks are limited.
|Thread: Power riveting with a hammer drill|
A client has asked me to make two 'Cowcatchers' for a large locomotive, each just over two feet wide, made from ⅛" steel bar, 1" and ¾" wide for the forward jutting verticals, crossed by four horizontal rails of 1/8* x ½" section. The drawing showed every crossover fastened through with a nut and bolt, which looked really ugly and much more likely to snag a dead cow than to push it aside, and so I suggested using round head rivets instead, to which the client readily agreed. Hmm .. seven verticals and four rails, that's 28 rivetted joints, times two cowcatchers, so over fifty rivets to set …
At this point an image of shipyard rivetters with their powerful hammers making short work of huge rivets came to mind. Having recently used my old hammer-drill to poke holes in a concrete floor, and knowing I could select 'hammer only' I wondered if I could do something similar, albeit on a much smaller scale. Worth a try, I thought.
I already had 3/16" x ½" steel rivets to hand, and a pair of hex bodied rivet sets to suit, but how to mount a rivet set in the drill ? The answer was to buy the smallest (and hence, cheapest) SDS drillbit and sacrifice it for the stem ...
.. then drill one of my rivet sets to accommodate the shaft. I had to heat the end to soften it first, then drilled and countersunk the hole ...
after which the two components wet silver-soldered together, making sure the business end of the set stayed relatively cool. Simple really, and when mounted in the drill it looked quite purposeful ...
With the other rivet set mounted solidly in the vice I put together components for a trial go, i.e. two pieces of ⅛" bar, drilled, and located on one of my rivets, its head nestling in the upturned tool in the vice.
I picked up the drill, located the tool hollow on the rivet stem, gave it a very short burst of hammer blows, and looked at the result. After more hammering trials, and some modification of the powered set (basically grinding back to make it shallower), it quickly produce very acceptable results. Impressively, the joints were completely rigid after just a second or so, but I carried on for a little longer to get the best finished effect I could.
My rivets are just a little too short to give a full round head, hence the shallower set, but it's not worth using ¾" rivets ( the next incremental length available in my searches) as they would be too long and all need shortening. The results achieved give me confidence that the 'cowcatchers' will be rivetted quickly, strongly and uniformly by this method. It works so well that I thought it worth posting here in case others can use the idea.
Regards to all, Ken.
|Thread: Free Plastic|
Graham, will you please include me in this deal, whenever you can, and ignore the email I sent earlier today; my fault for not keeping abreast of developments in the thread,
Regards, ken king, King Design
|Thread: Rubber Sheeting on Offer|
.. and I'd like four sheets too, please Ian. PayPal payment will be made today.
|Thread: My first ball-turning job|
I've just had a lot of fun with my new ball-turning attachment on my Myford. I bought the attachment, from RDG Tools (no connection) in response to a client's request for six short, ball-headed stanchions. I soon worked out how best to tackle the job ( an indication that it was a really simple challenge) and then thoroughly enjoyed the exercise. Here's the setup, with an internally threaded work holder in the chuck, and a piece in progress. This is a posed photograph, I hasten to add; I always fully remove the dust sheet , and store work-in-waiting a little further from the action …..
….. and at the end I had produced the goods somewhat faster than anticipated. I'm very pleased with the way the tooling worked, and the finish it gave …..
The only niggle was that the triangular tool tip couldn't reach right into the neck, partly due to the nearby flange, and so a form tool was employed in that corner. I'm now looking forward to the next ball-turning request, anyone for stanchions ?
|Thread: Radiussed ends by mill and file|
I recently had to make a batch of six aluminium brackets for retracting undercarriage legs on a ¼ scale model of the famous Hurricane fighter aircraft. The brackets were essentially rings, to fit round the legs, with a rectangular boss to which would be attached the undercarriage door. Brackets are locked to the leg via a single grubscrew, and doors are attached to the rectangular boss with M2 bolts. The ring part is ⅜" deep and has a wall thickness of 1/16" . The photos below shows finished brackets in place …. (yes, I know there are more than six, and also that I forgot to reset the camera date, again) …..
I hit on the following method for making the ring part of the brackets, and whilst it has almost certainly been done before it was original thought for me, and as it might not yet have occurred to others I thought I'd share it. So for what it's worth, here it is.
Whenever I'm to radius the end of a part, with a concentric hole, I make a pair of what I call 'filing buttons' from silver steel, and harden them. With two diameters, one to fit halfway into the hole, and the other to give the finished radius, the pair of buttons provide filing guides, and work very well. For these aircraft parts I used an extension of this technique in the milling machine.
Firstly I made six ¾" dia holes in ⅜" x 1" bar and cut it into six pieces. These were slid onto a short length of ¾" rod, leaving space at the ends for the insertion of two 'buttons'. In the following photos I'm using finished parts to illustrate the method as I lacked the foresight to photograph as I went along, nor had any thought of making it a thread here. In the next two photos you see a stack of four parts being assembled …. (the vice can't take six) ….
and here with a 'button in each end ……..
You can see that each part is already drilled, tapped, and has a grubscrew fitted, which I used to lock them to the inner rod. This is not an essential feature, and plain pieces will stay aligned equally well once machining starts. The assembled package was then placed in the milling machine vice, with each 'button' resting on a parallel, as shown here …...
Cutter height was adjusted until it just cleared the 'buttons', then multiple cuts were taken to produce a series of narrow facets very close to the finished curve. This was simply achieved because the 'buttons' ride on the parallels and all that is needed is to slacken the vice, roll the stack slightly, retighten and take the next cut. After facetting was complete the stack was transferred to the bench, where very little filing was required to blend the facets to the finished curve.
Hope someone finds that useful,
|Thread: unable to place ad|
Katy confirmed that this was an M.E. site problem, and tracked it down to an apostrophe in the photograph file name, where the title was abbreviated to " motor/g'box". This was mot something I could see, and even if I had I wouldn't have expected normal punctuation to be a problem, but apparently apostrophes indicate to the computer that an instruction is following, to be ended by a second apostrophe. When the second did not appear the computer took fright and suspected me of being an invader, so shut me out. A classic case of ' The computer says no!'
I sent copy to Katy and she has now sorted the problem and placed tha ad for me. Thanks Katy !
I'm now hoping to receive a simple explanation of what caused the problem, so that I can avoid it happening again.
Hi Neil and Jason, thanks for looking into this, but I'm blowed if I can see what I'm doing that the system doesn't like - no special characters for example, just a photo and descriptive text. I've left line spaces here and there to make details clearer, but surely that can't be it, can it ? I hadn't thought about the problem being at my end as I had just placed another, similar ad with no problem, and the error message said THE SITE had a problem. Just goes to show that you can't believe everything you read, doesn't it ?
What a pity I hadn't copied the ad to you as a message, then you could have tried placing it as a test …. hmmm, might think about that if I can't get it to work soon.
Neil, should have read 'just TRIED again', b….y spell checker getting above itself again,
Hello Neil, just died again and the problem persists. Here's copy of the error message, it appears twice as shown, after about a minute from pressing the 'place ad' button.
Sorry - the website has an error and the page you requested cannot be displayed at the moment. Please try again later.
Hope you can sort it out soon,
I've been trying to place advertisements of machine parts for sale. A friend is disposing of a machine from his factory and I thought some of the bits might be useful to model engineers. The first, for a leadscrew assembly was placed without difficulty, but the second, for a large motor/gearbox unit, is not accepted ( after a while) and a message apologises for a site problem being responsible for inability to place my ad. What went wrong, and why did it have to happen whilst I was typing in my second ad ?
Will the problem be fixed soon ? I do hope so,
|Thread: Increasing working space of a Centec mill|
Can I please pick the brains of anyone who has added raising blocks to a Centec 2A mill to increase workspace under the vertical spindle ? Occasionally, well once, I have seen such items advertised, but missed them. Now I'd like to make my own, and wondered if a drawing is readily available to shorten the timescale for me. Should I opt for cast iron over mild steel ? All inputs gratefully received,
|Thread: Chimney and smokebox for 'Sweet William'|
Some more work on my client's 'Sweet William' saddle tank locomotive, starting with the chimney. It comprises three parts, a nicely turned and finished brass top casting, A length of standard copper pipe for the stack, and an unfinished bottom casting.
After squaring the pipe end the top was soon silver soldered in place and the pipe cut to finished length. The bottom casting arrived roughly bored through but externally was as cast.
It was carefully set up in the four jaw chuck and the bore was cleaned out to fit the pipe, making sure it all ran true, then as much as possible of the outside was skimmed. this wasn't much because the section quickly changes from circular to something else !
The rest of the outside needed much heavy filing but eventually yielded a fair surface.
The underside needed dressing as well, and this was done by wrapping coarse wet & dry paper over the smokebox and sliding the casting around the curve … for a considerable time. I wanted to achieve a dressed surface to contact the smokebox all around the perimeter and pretty much got there by the time my wrist gave up.
Here it is in place, thankfully no unsightly gaps showing.
The pipe protrudes right through the base and the two are riveted together. At present they are held in the correct position with soft solder whilst I wait for copper rivets. It makes a nice chimney.
Next I turned my attention to the hinges and locking mechanism of the smokebox door. On the drawing supplied the hinges look simple and straightforward, just straight bars across the domed door, with two lugs on the smokebox face and a hinge pin through the lot. Not so ! For a start, the bars intersect with a compound curve, so not straight after all. Additionally, as drawn, the door perimeter extends beyond the hinge line, meaning the door closing face would have to be relieved for swing clearance, giving an unsightly gap (U.G.) You may have gathered by now that I can't stand U.G.'s The actual door was a little oversize which made things worse, and I decided to move the hinge line outward with revised offset lugs. The hinge bars had first to be milled to an approximate fit on the curves …..
… then filed and chamfered until a reasonable mating occurred ….
, after which the front faces, comprising two facets, were milled
Bars are currently screwed to the door but will soon be riveted. The latching and locking components, as supplied, needed some modification. With no drawing of this part I made it up as I went along. The hand wheel boss is much smaller than the boss on the door and didn't look right at all, so I turned a brass washer to transition from one diameter to the other, and it looks a lot better.
The door now swings freely and sits and locks nicely flush, the latch engaging in a removable slotted crossbar.
With a little riveting still to do the smokebox assembly nevertheless is an attractive addition to the front of the locomotive. I'm sorry this shot is sideways.
Thanks for viewing,
|Thread: Correcting worn slideways|
Thanks Phil, as you said, plenty of information and food for thought there. The first thing must be to strip the table and cross-slide ways to measure the extent of wear to be corrected, then decide which approach to use. thanks again,
I've acquired a Centec 2A milling machine which has previously been used for just one specific repetitive job. This has resulted in noticeable slide way wear over the centre portion of table travel. Can anyone suggest the best way of addressing this and getting the slide ways true and parallel ? Is it something I could tackle with abrasive blocks, scrapers etc or is it a case for a slide ways grinding company ? Your comments and suggestions please,
|Thread: Jet engine swivelling mounts|
I thought I'd post these pictures, not because the parts are particularly tricky, but because the application is ambitious, experimental, ground-breaking, pushing the frontiers of a technical hobby….. yes, all those things.
It started with a phone call from an aeromodeller, telling me he wanted to build a Wren-jet powered aircraft and to be able to swivel the engine, once in flight, to direct the thrust downward, in the hope of achieving a hover, a la Harrier. Could I make the parts need for the swivelling engine mounts ? Naturally I jumped at the chance, and in due course his very clear drawings arrived for inspection. A deal was struck and I set to work. The parts comprise a mix of steel and light alloy, in ones or twos. In the photos the background paper has a 5mm grid, so some idea of sizes can be obtained.
These are steel …. (it's a standard M6 capscrew, but with a hardened steel sleeve) ..
whilst these are light alloy, in pairs ...
and finally, the whole ensemble ...
This modeller, who wishes to remain anonymous until the project is further advanced, is well aware of the control challenges to be faced and is already developing control systems and software for separate aspects of motion. I sincerely hope that we will have the chance to learn more in due course. I can only admire his spirit of adventure and dedication to his objective.
|Thread: Rivet, rivet, rivet ...|
Hello Jason, thanks for that. I went straight to EKP's website and found exactly what I was looking for,
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