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RichardShute: When I got my milling machine it was missing the overarm bearing for the outboard end of a horizontal arbor. Mostly I use the machine as a vertical, but it has always irritated me that I haven't got 'the full set' with the machine and as a two year-long scan of fleaBay failed to dig one up I decided to bite the bullet and make one. I made a pattern by laminating some 1" plywood to get a block thick enough. This was a mistake as changes in temperature and humidity, even after painting it, made the laminations move about and show up. Again and again and again..... sand it smooth, (re)paint it wait two days and the laminations are sticking out like a sore thumb. It eventually got less mobile, by which time it probably had 10 or 12 coats of paint and sanding. It was less than ideal, but adequate so I took it in and had it cast at a local foundry. Not exactly cheap, but about what I would have paid had one turned up for sale so not cripling either. But obviously I need to machine it. Here's the pattern and casting side by side. The first thing to do is get a reference so I took a swipe across the front face with a fly cutter. It's not a hugely important surface, but it's an easy one to give me a reasonable surface to mount it and measure from for. I also took a cut along what will be the top face as a starting point for setting the casting up on an angle plate. Then hogged out the bulk of where the dovetail will be. as well as taking a cleaning cut down the side of the block for alignment and setting up later. The dovetails will be hand scraped to match the slides on the machine, but unfortunately I had assumed they were 60deg which would have been easy to use a dovetail cutter to get close, but in fact on measuring them, they are 55deg, strange but true. So I decided to cut them on the shaper. Start by making a gauge to check the bearing block as once it is big enough to fit on the machine it's already too big and adjusting the fit will only make it more too biggerer. I grabbed a bit of 2x2 sq steel and set the donkey saw to work on that while I ground up a tool for the shaper. It needs to be less than 55deg between the flanks so that I can cut the dovetail and still have some side clearance. No particular angle was set, I just eye-balled it up to be less than the dovetail by probably 8~10 deg. The saw's done its job and now I set the vice straight on the shaper and put the blank up to take a lick off the top to clean it up and give me a reference. and then set up the fine tipped tool for the cutting the vee. As is usual it took far longer to set it all up than to actually do the job. The shaper is a bit small for the job, not in terms of stroke, but the necessary side movement to get the tool to the side of the block. I did not want to put the vee in the top of the block as I'm essentially lazy and the machine has no powered vertical feed, but does have a powered horizontal. This makes it much easier to get a nice finish on at least one side of the vee. I roughed out the groove using the table vertical slide and advanced the tool slide down and in. The great thing with shapers is they eat metal quickly and yet still give a good finish. Once the bulk of the groove was clear, I re-set the table support leg and took a finer cut across the flat of the groove. Then backed the tool slide up and took a finishing cut down the angled face with the hand feed on the tool slide, set at an angle (ie 90-55 = 35deg). And here's the finished gauge blank. A quick trial fit onto the dovetail and it is close. No the dovetail is not rusty, just an oil stain, the camera is not very flattering. I've not blued it yet, but I don't think it will be too far off. Once it is right, I will take a swipe off the 'back' to true the face to the vee and then cut it in half. I can then use the two parts inside the dovetail as yet to be made on the top of the bearing block and measure between them to get a indication of the width of the dovetail. Yes, I could do that by measureing between rollers, but I need an angle gauge to get the flanks right anyway, so I might as well use the same gauge for both jobs. It's a bit of a background project this, so don't hold you breath for the next bit, but I will get round to it..... sometime. Richard

Bogstandard: I fully understand your problem about the angles. My machine has the 55 degree dovetail, and when I bought a horizontal arbor at the right price, that came wih a 50 deg dovetail. Not wanting to change the original item, I came up with a solution of a pair of converter blocks that did the job perfectly. http://madmodder.net/index.php?topic=2083.0 I am sure you will get your problem solved with very little trouble. Bogs

RichardShute: I didn't realise how prophetic my tongue in cheek title for this was going to proove to be. After making the gauge and matching it to the dovetail on the machine the next step is to machine the dovetails in the bearing casting. I had kept the casting mounted on the angle plate from milling the top and mounted it onto the shaper in preparation. It was immediately obvious that the tool I had ground for the gauge could not be used as the 'other side' of the dovetail fouled the work head on the shaper. I have a cranked Armstrong type lathe tool holder for 1/4" HSS bits, but only a right hand one. I could borrow a left hand one, but that was for only 3/16" HSS aaarrrgh... Right! bite the bullet and make a proper swivel head shaper tool holder. A while ago I was lucky to come by a quantity of En16 bar, a few 3' lengths, but only 35mm dia, none bigger none smaller, so I had to make the tool according to the material available. I used it and turned a pin 5/8dia and cross drilled it 15/64ths and then filed out the corners to take the cutter bit. I deliberately left the hole undersized and ground a hollow in the end of a 1/4" HSS blank with a mini-grinder (a not-a-Dremel) and a small ball stone. Then in four or five goes I shoved it through the hole as a poor-man's broach-ish. Press it in about 1/8", knock it out with a soft steel punch (4" nail - ugh), file out the 'burr' try again. It is tricky to keep it straight and square to the pin and not the sort of thing to make a habit out of, but for a one off, it's adequate. Sorry, I forgot to take photo's of all that palava. I put a lump of bar in the mill and took 10mm off either side for a length of about 4" to create the 5/8" thick shank of the tool holder and then took a cut across the top to make what will be the back face. Milling the side of a 4" long overhung bar isn't the most wonderful scheme, but as you can see the finish is very good. There was no chatter to talk of and for this job precise dimensional accuracy is not an issue. Turn the bar on its side to mill what will become the front face of the head and set back about 1/4" from that, the front of the shank. Drill and ream the hole for the bit-holder and mount it on a bolt in the rotary table. Again, it's a bit of a liberty, the direction of the cutter works so as to slacken the nut retaining the job, but it was a 5/8 high tensile bolt and it was done up TIGHT and I was reasonably gentle with the rotary table feed. I milled down one side till the cutter was in line with the hole centre, round the end to a radius all the way round and straight up the other side and it's all sorted. De-burr, sweep up the swarf, one step forward Right, now on with the real job... After half an hour of rhythmic metal munching I got what I was after Another step forward, wow! What a day, I may have to lie down for a while.... Richard

Brass_Machine: Nice! Envious of you guys with shapers... :bow: Eric

Rob.Wilson: Hi Richard   :clap: :clap: :clap: :clap: I have the same problem ,, go in to  the shop to to make something and end up having to make something else first  ::)  ,,, The shaper tool you have made is on my list to do  :dremel: Great Job  :clap: :clap: :clap: Rob

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