PenrithBeacon Posted March 12, 2014 Share Posted March 12, 2014 Of course, it all depends on the type of reamer. Hand reamers don't usually behave well when used in machines, and machine reamers don't behave well when trying to use them by hand... It's perfectly possible that workshop techniques have moved on from when I was an apprentice 50 yrs ago, but then there were just reamers. There was a taper, an intermediate and a parallel styles (to be used one after the other, particularly if you were reaming a blind hole), but they were just reamers. How does a hand and a machine reamer differ? Regards Link to post Share on other sites More sharing options...
Mike Boucher Posted March 12, 2014 Share Posted March 12, 2014 It's perfectly possible that workshop techniques have moved on from when I was an apprentice 50 yrs ago, but then there were just reamers. There was a taper, an intermediate and a parallel styles (to be used one after the other, particularly if you were reaming a blind hole), but they were just reamers. How does a hand and a machine reamer differ? Regards A hand reamer usually has a considerable taper at the tip to ensure it goes in square. It usually has square ground into the end of the shank so you can put it in a T handle tap wrench, and also often a center hole so you can hold it in the lathe using your tailstock center. The flutes are usually straight (not spiraled) so the flutes don't pull the reamer into the hole as its turning, to make it easier to turn by hand. And they're made to cut at very low speeds. A machine reamer has almost no taper at the tip, just enough to start it in the hole, as the machine will hold it square to the work. The diameter is constant across the entire cutting surface. And the shank is round all the way to the end. Link to post Share on other sites More sharing options...
PenrithBeacon Posted March 12, 2014 Share Posted March 12, 2014 A hand reamer usually has a considerable taper at the tip to ensure it goes in square. It usually has square ground into the end of the shank so you can put it in a T handle tap wrench, and also often a center hole so you can hold it in the lathe using your tailstock center. The flutes are usually straight (not spiraled) so the flutes don't pull the reamer into the hole as its turning, to make it easier to turn by hand. And they're made to cut at very low speeds. A machine reamer has almost no taper at the tip, just enough to start it in the hole, as the machine will hold it square to the work. The diameter is constant across the entire cutting surface. And the shank is round all the way to the end. When a reamer has spiral flutes they are always counter clockwise so that the reamer cannot screw itself into the hole, this is the traditional form. The taper on a reamer is there to help the craftsman feed the reamer into the hole; this is true when the tool is being used in a machine or the bench. It is not a great idea to use a parallel reamer without first using a taper and you would normally only need to use a parallel reamer to finish off a blind hole. As I said in my post earlier, reamers would normally come in a set of three. The only difference between a hand and machine reamer you describe is the absence of a square end to the machine reamer, presumably a modern innovation and one which is entirely understandable in a tool that isn't intended to be used on a fitting bench. Regards Link to post Share on other sites More sharing options...
ozzyo Posted March 12, 2014 Author Share Posted March 12, 2014 When a reamer has spiral flutes they are always counter clockwise so that the reamer cannot screw itself into the hole, this is the traditional form. The taper on a reamer is there to help the craftsman feed the reamer into the hole; this is true when the tool is being used in a machine or the bench. It is not a great idea to use a parallel reamer without first using a taper and you would normally only need to use a parallel reamer to finish off a blind hole. As I said in my post earlier, reamers would normally come in a set of three. The only difference between a hand and machine reamer you describe is the absence of a square end to the machine reamer, presumably a modern innovation and one which is entirely understandable in a tool that isn't intended to be used on a fitting bench. Regards Hello all, I think that some of you are getting mixed up between taps and reamers. After ??years in engineering I've never seen a taper reamer that would be used in a blind hole, a plug tap yes (or No three). Most of the time a reamer is used to give a good fit for a bolt to go through, unless it's used like I did with a tapered pin to fit in. Or as we use them to give a good running fit in a bearing. Back to the build. As I mentioned. The frame spacers are a bit on the narrow side for me, so this is what I did. It's not elegant but it should work. All it is, is some L angle brass soldered to the spacers to pack them out from the main frames, After cutting the bits out that I don't require, Tack soldered into place in the frame, I only want to do this on one side as I want to check that the inside con. rods will clear a frame spacer, The crank axle after a bit of a clean up, and a spin in the lathe to remove about 10 thou from the outside webs. As I mentioned before the frames are a bit on the tight side, so I want to get the crank axle to have "some" play on the inside, but I'll take that up on the outside between the axle box's and the wheels, A quick test fit of both side frames and the crank axle, just to see that it fits, Well I just had to take this photo as well. It's going to be a big loco, OzzyO. Link to post Share on other sites More sharing options...
ozzyo Posted March 13, 2014 Author Share Posted March 13, 2014 Hello all, finishing off the crank axle, this involved removing the small pieces of axle between the crank webs. In the instruction they recommend using a slitting disc, I decided against this and decided to use a piercing saw. This did the job well leaving very little cleaning up to do between the crank webs, The con rods in place before cleaning up, The crank axle from in front showing how small the clearance is between the rods and the inside of the webs, Starting work on the cross-heads, not that much to do to them apart from removing the four bolts and drilling and taping the cross-head 12BA for the gudgeon pin, Getting ready to put the bits together, for the gudgeon pin I'm using some hex. headed steel bolts, The inside rods, etc. ready to be fitted to the cylinders and slide bars, The casting and etches for the inside cylinders etc. Starting work on the inside cylinders and slide bars, the top two slide bars in place. These took quite a bit of cleaning up to get a good sliding fit on the cross-heads, From below showing the two small holes for the pegs on the slide bars to locate in to, All the slide bars in position after a quick grit-blast, All of the inside parts together for the first time, not a lot to show for the best part of a days work. But some time that's how it goes. One good thing about Anne is that she doesn't have any inside valve gear to worry about, OzzyO. Link to post Share on other sites More sharing options...
3 link Posted March 14, 2014 Share Posted March 14, 2014 Hello Matey, Just a quick question as I'm pushed for time as usual, how do the con rods fix to the big ends on the crank shaft ? Have a catch up soon. ATB, Martyn. Link to post Share on other sites More sharing options...
ozzyo Posted March 14, 2014 Author Share Posted March 14, 2014 Hello all, the con rods both have cut outs at the big end one is a U shaped one and the other one n shaped. So when you fit them together you end up with a O shaped hole. So in this puzzle U + n = O. OzzyO. Link to post Share on other sites More sharing options...
Mike Boucher Posted March 14, 2014 Share Posted March 14, 2014 When a reamer has spiral flutes they are always counter clockwise so that the reamer cannot screw itself into the hole, this is the traditional form. The taper on a reamer is there to help the craftsman feed the reamer into the hole; this is true when the tool is being used in a machine or the bench. It is not a great idea to use a parallel reamer without first using a taper and you would normally only need to use a parallel reamer to finish off a blind hole. As I said in my post earlier, reamers would normally come in a set of three. The only difference between a hand and machine reamer you describe is the absence of a square end to the machine reamer, presumably a modern innovation and one which is entirely understandable in a tool that isn't intended to be used on a fitting bench. Regards Not to derail this thread any more (sorry OzzyO), but spiral flute reamers come with spirals in either direction, depending on which way you want the chips to go. If they're "left hand", they push the chips forward, which is quite useful for a through hole application, but not at all desirable for a blind hole. And I use parallel reamers all the time without using a taper reamer, because 1) I'm using it in a machine and 2) the drilled hole is within a 1/64th inch of the size I'm reaming to. The chamfer on the machine reamer is more than sufficient to start the reamer in the hole. For more info, check out this page from the MSC industrial supply catalog: (they use the term "chucking reamer" instead of "machine reamer", but everything else still applies.) http://www.mscdirect.com/FlyerView?pagelabel=221&search=02210649&contentPath=/sales-catalogs/big-book Link to post Share on other sites More sharing options...
PenrithBeacon Posted March 14, 2014 Share Posted March 14, 2014 Not to derail this thread any more (sorry OzzyO), but spiral flute reamers come with spirals in either direction, depending on which way you want the chips to go. If they're "left hand", they push the chips forward, which is quite useful for a through hole application, but not at all desirable for a blind hole. And I use parallel reamers all the time without using a taper reamer, because 1) I'm using it in a machine and 2) the drilled hole is within a 1/64th inch of the size I'm reaming to. The chamfer on the machine reamer is more than sufficient to start the reamer in the hole. For more info, check out this page from the MSC industrial supply catalog: (they use the term "chucking reamer" instead of "machine reamer", but everything else still applies.) http://www.mscdirect.com/FlyerView?pagelabel=221&search=02210649&contentPath=/sales-catalogs/big-book Thank you, clearly matters have moved on since the 1960s, and my regrets to 'OzzyO' for my forgetfulness. Regards Link to post Share on other sites More sharing options...
ozzyo Posted March 14, 2014 Author Share Posted March 14, 2014 Hello all, quit a bit done today, as I mentioned in one of my last messages I had a worry about one of the frame spacers, after doing some checking it all looks OK apart from when the axle is at full travel upwards, After checking with the gearbox, I found that I had to remove a small section of the loco brake cylinder support, I'll fit the brake cylinder later on when I've checked out the brake gear, Some of the next parts I'll be looking at, the cylinder former, front motion bracket and rear motion bracket support. Some will have to have metal removed and one will have metal added, Formed to shape and the others soldered together, Four photos of the part completed frames, The last two frame spacers, both of these spacers are at the rear of the main frames. As with all of the spacers I've had to add some packing to them. The main problem with both of these spacers is that they fit in half etched slots in the main frames. The top one I've added strips along the edges that will fit against the main frames, the bottom one is more of a problem in that all of the ends fit in the slots. To do this one I've used some brass L angle to the ends and filed off the bottom of the L, When I test fitted this one I found that it fouled the CSBs so I had to cut out two parts at the bottom corners, The two spacers in place, with a bit of luck I maybe able to use the rear one as the tie-down for the motor. I'm having second thoughts about the rear spacer and I may change it later on, The rear end frames now in place, it's starting to look like a Princess now, This is one area that I could end up having fun with. When the cranks are at B.D.C. the rods are going to be very close to the rear boige cross beam. This photo is showing the worst case scenario, with the axle at the bottom of its travel as well, OzzyO. Link to post Share on other sites More sharing options...
3 link Posted March 15, 2014 Share Posted March 15, 2014 Morning Matey, Now that is one big loco . Regarding the possible fouling of the bogie, I think once you have got some weight in her it will be fine, if not you will have to trim down the top of the rear bogie cross beam. And if that does not work you can always bend the rods to fit . ATB, Martyn. Link to post Share on other sites More sharing options...
JeffP Posted March 15, 2014 Share Posted March 15, 2014 It does look imposing..and those extra rivets just nail it for me...they draw the eye, make it look like a real one. Link to post Share on other sites More sharing options...
ozzyo Posted March 17, 2014 Author Share Posted March 17, 2014 Hello all, after a good days rugby on Sat. and a days rest on Sun. its time for a quick update on Anne. Seeing what the frames look like with the wheels in place. The front set, with these in place I found that cotter pin on the inside big end fouled the inner spacer, not a big problem I'll just remove the cotter pin extension, I got the rear footplate supports in place, now these look a bit to far forward, This proved to be the case when I came to fit the rear wheels, I'd not been that keen on having the two supports and the frame cross member having all of them soldered joints so close together. So I decided to make all three out of one piece, With the slots for the frames cut in, I'm undecided about cutting the holes in the footplate supports, I probable will do, After this I decided to make a start on the motion bracket assemble, Up to now there's eight pieces in this assemble, with more to follow. Looking at these photos it looks like the front end is a bit on the low side. Some packing will sort this out, Anne is going back in her box for a few days (back to work on her on Sat. if all goes to plan) so I can get back to some commission work. So I'll be restarting on the County back in my build thread. OzzyO. Link to post Share on other sites More sharing options...
JeffP Posted March 17, 2014 Share Posted March 17, 2014 Ozzy, I'm not sure if I missed it, but I think you did: how did you drill all the holes for your rivets? Link to post Share on other sites More sharing options...
Michael Delamar Posted March 17, 2014 Share Posted March 17, 2014 please dont take this the wrong way but will the csb wires be hidden when its finished? If you can look in to see the inside rods? Link to post Share on other sites More sharing options...
ozzyo Posted March 17, 2014 Author Share Posted March 17, 2014 Ozzy, I'm not sure if I missed it, but I think you did: how did you drill all the holes for your rivets? Hello JeffP, for drilling the holes I used a 0.85mm drill in my pillar drill running at about 1,800 rpm. The frames as supplied, the front five spring hangers (No. one at the left) I used the half etched rivet positions, Then I marked out all of the rivets at the rear of the frames, using the top of the frames as a datum. To drill this number of holes I taped the frames to a block of wood so that they would not move, this also helped to reduce the amount of break out on the back of the holes, After removing from the block of wood, please dont take this the wrong way but will the csb wires be hidden when its finished? If you can look in to see the inside rods? Hello Michael, in this photo you can see a horizontal line running along the frames just above the horn guide cut outs, this is the centre line for the CSBs With a CSB in place, this is just above all of the holes in the frames at rest, but when the engine has got some weight to it it will move them up a bit, so you will not see them. A close up of the front frame hole with a CSB in place, it's not in view, the brass shadow that you can see to the right of the hole is the front CSB pivot, it's just above the front spring hanger, From above this is what you'll see, I'm more worried about the two big screw heads than the CSBs! HTH OzzyO. Link to post Share on other sites More sharing options...
Horsetan Posted March 18, 2014 Share Posted March 18, 2014 Looks like the wood block will come in handy when trying to stretch a chassis section from 32mm to 33.3mm..... Am very taken by that crank axle. Link to post Share on other sites More sharing options...
JeffP Posted March 18, 2014 Share Posted March 18, 2014 Thanks for the explanation Ozzy. I might have to resort to a pinchuck in a collet to hold a drill that small. Luckily my pillar drill has a collet chuck available. Link to post Share on other sites More sharing options...
buffalo Posted March 18, 2014 Share Posted March 18, 2014 Thanks for the explanation Ozzy. I might have to resort to a pinchuck in a collet to hold a drill that small. Luckily my pillar drill has a collet chuck available. Something like an Eclipse 160 pin chuck is ideal. 0.25-2.50mm capacity (three collets) and a 1/4" diameter shaft to fit drill/mill/lathe. Also works comfortably in the hand (at least, it does in mine). Nick Link to post Share on other sites More sharing options...
JeffP Posted March 18, 2014 Share Posted March 18, 2014 That's the one I have. I HAD a cheap set from ebay, but they are in a drawer awaiting me trying to get new METAL collets. The supplied plastic ones didn't grip at all, sadly. Even used in my fingers, the drill disappeared inside the chuck in no time. Link to post Share on other sites More sharing options...
ozzyo Posted March 18, 2014 Author Share Posted March 18, 2014 Hello all, just came across this web site, it may interest some of you. http://modelrailwayparts.com/index.html OzzyO. Link to post Share on other sites More sharing options...
JeffP Posted March 18, 2014 Share Posted March 18, 2014 Nice..prices look OK. Link to post Share on other sites More sharing options...
steve fay Posted March 19, 2014 Share Posted March 19, 2014 Plates have arrived, Anne has her identity Link to post Share on other sites More sharing options...
JeffP Posted March 19, 2014 Share Posted March 19, 2014 I thought Anne was Ozzy's? Link to post Share on other sites More sharing options...
steve fay Posted March 19, 2014 Share Posted March 19, 2014 I thought Anne was Ozzy's? It is but seen as he knocked up my steps and couplings I though I would sort his plates out for him Link to post Share on other sites More sharing options...
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