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Re: U3 top slide (part #150190) damage
Try turning it around. Can you bolt the slide to the carriage to drill out the damaged portion? Drill bit or milling cutter held in a chuck or cutter holder mounted on the spindle? That way you don't have to swing the top slide in the 4-jaw. You'd need an angle plate or something similar. Have you considered making a milling attachment similar to those used on mini-lathes and even the Atlas lathes like I have? Not suggesting you buy this one, just as a reference:? Buying it would be very not cost-effective! ;) better cost-wise, photos not as good, but could serve as inspiration.? I have found, generally speaking, that to do any one job, you usually find you need to do ten other things. First. So you need to fix your lathe before you can fix your lathe. But you can use it as a drill press, horizontal boring machine, and possibly a milling machine without that top slide, if you can figure out how to clamp material to it.? Might be some good inspiration here:??in particular, look at his Dremel milling attachment. You might be able to put something like that together and make a new top slide with it. Also, you could make something like this on the machines you have, with the stuff I believe you already have, and use it to hold the top slide to do the machining you need to do to fix it:??His is O1 tool steel, but you could make such a thing from aluminum. His is even close to the dimensions you'd need, I think. You could use your 4-jaw chuck to hold a tool for fly-cutting the exterior surfaces to square them up, and make end mill holders for cutting the 90 degree interior angle. Or do some very light milling on your drill press...? Lots of ways to do things. ;) Bill in OKC William R. Meyers, MSgt, USAF(Ret.) Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY! Physics doesn't care about your schedule. The only reason I know anything is because I've done it wrong enough times to START to know better
On Monday, August 22, 2022 at 08:00:16 AM CDT, sawbona@... <sawbona@...> wrote:
Hello: On Sun, Aug 21, 2022 at 07:01 PM, @juliushenrymarx wrote: I started to sketch a solution ...It seems that it boils down to this: Sorry for the freehand, don't have a drawing board nowdays and never cared for CAD. As you can see, the weak spot of the top slide is a tiny cylinder measuring ID 11.0 mm x OD 12.0 mm x 1.0 mm. This 1.0 mm x 1.0 mm cylindrical section of aluminium takes all loads applied to the slide. To make things even worse yet, the width of the narrow part of the dovetail is only 14.0 mm, which means that the ID of the hole for the mounting bolt is only 1.0 mm away from the dovetail at that point, so the mounting hole cannot be drilled any larger to add more metal. The solution, if there is one, may be the one Bill suggested. Plug and drill to replace the damaged section. But there's a hitch ... The slide is too long for the U3's available swing (need at least ~55 mm swing to mount it on the 4-jaw) so I won't be able to bore out the hole or make a recess from below to register the plug accurately on the slide. Not having a mill to do it, I'd have to carefully drill on the press and fit a pre-drilled plug with a permanent loctite type anaerobic. The plug would have to pre-drilled to use a smaller/custom mounting bolt ie: not the standard M5 allen head. Maybe flat head? This would allow the plug to be just a wee bit heftier, brass being my choice of metal to use. I confess I'm rather annoyed as I really did not expect to find this type of issues in the U3. Problems due to wear and tear in a 42 year old mini-lathe are unavoidable and to be expected. But all the problems I am encountering are (in my opinion) caused by bad design/manufacturing practises and make me wonder what else I'll find ahead. Best, JHM |
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Re: U3 top slide (part #150190) damage
Hello:
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On Sun, Aug 21, 2022 at 07:01 PM, @juliushenrymarx wrote: I started to sketch a solution ...It seems that it boils down to this: Sorry for the freehand, don't have a drawing board nowdays and never cared for CAD. As you can see, the weak spot of the top slide is a tiny cylinder measuring ID 11.0 mm x OD 12.0 mm x 1.0 mm. This 1.0 mm x 1.0 mm cylindrical section of aluminium takes all loads applied to the slide. To make things even worse yet, the width of the narrow part of the dovetail is only 14.0 mm, which means that the ID of the hole for the mounting bolt is only 1.0 mm away from the dovetail at that point, so the mounting hole cannot be drilled any larger to add more metal. The solution, if there is one, may be the one Bill suggested. Plug and drill to replace the damaged section. But there's a hitch ... The slide is too long for the U3's available swing (need at least ~55 mm swing to mount it on the 4-jaw) so I won't be able to bore out the hole or make a recess from below to register the plug accurately on the slide. Not having a mill to do it, I'd have to carefully drill on the press and fit a pre-drilled plug with a permanent loctite type anaerobic. The plug would have to pre-drilled to use a smaller/custom mounting bolt ie: not the standard M5 allen head. Maybe flat head? This would allow the plug to be just a wee bit heftier, brass being my choice of metal to use. I confess I'm rather annoyed as I really did not expect to find this type of issues in the U3. Problems due to wear and tear in a 42 year old mini-lathe are unavoidable and to be expected. But all the problems I am encountering are (in my opinion) caused by bad design/manufacturing practises and make me wonder what else I'll find ahead. Best, JHM |
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Re: U3 top slide (part #150190) damage
Not a U3 owner, but if you cut a disc of aluminum to fit that hole and loctite it in place, you can re-drill and countersink it, and be able to use it again. Or you could replace the part with one you made to match it. Cutting the dovetails by hand could be an interesting job. :) Bill in OKC? William R. Meyers, MSgt, USAF(Ret.) Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY! Physics doesn't care about your schedule. The only reason I know anything is because I've done it wrong enough times to START to know better
On Sunday, August 21, 2022 at 09:56:19 AM CDT, sawbona@... <sawbona@...> wrote:
Hello: Once I cleaned up and checked movement and reversibility on my recently acquired 4-jaw chuck, I started off on making some flat stock from 10 mm brass stems/spindles I got from a chap I sometimes purchase plumbing supplies and kitchen/bathtoom fixtures from. He very graciously gifted me with ~ 1.5 kg. of various lengths which will be very useful.? 8^D But I digress ... As I took apart and thoroughly cleaned the top slide's aluminium body and inspected it, I found this: No need of a loupe to realise that the well that receives the M6 allen head bolt that screws into the 'T' nut in the carrier's slot to secure the slide in the desired position is cracked, no idea how this got this way. I had only put the slide in place once or twice to see how it would fit/work and as I found problems with the gib and the adjustment screws, put it aside till I could fix it properly. Is all this my own doing or is it part of this U3's history? After all, at serial #80070243 it has just turned 42 - ie: 80 => 1980 07 => July And just like health issues for us, stress/strain in metals is a fact of life. But I digress, again ... If I set the slide in its place on the carrier (without the bolt/'T' nut), I find that the deformation you can see in the photos does not allow it to turn freely or sit flat against the surface of the carrier, so this problem needs to be addressed, lest I put it in use and get this damn thingy flown into my face in the midst of a job. Evaluation: The top slide has a thickness of 8.00 mm: The recess in the carrier ie: where the top slide should sit and turn ~ 40¡ã CW or ACW, is a cylinder 2.80 mm x 12.00 mm: But the recess in the top slide's aluminium body ie: where the M6 bolt sits measures 7.50/8.00 x 11.00 mm. The 8.00 mm is where it has cracked open. It would seem that there is very little material (between the recess in the carrier and the recess in the top slide) to take the stress of the bolt securing the top slide in position. ie: Between the diameter of the carrier's recess and the internal diameter of the top slide's M6 bolt's recess there is only a 1.00 mm difference. If my math is correct, this means that the cylindrical *wall* of the top slide's recess has a thickness of only 0.50 mm. to take the stress of the bolt. Likewise, between the depth of the carrier's recess and the depth of the top slide's M6 bolt's recess there is only a 0.50 mm difference. If my math is correct, this means that the bottom of the top slide's recess has a thickness of only 0.50 mm. to take the stress of the bolt. So ... This whole thing is held in place by a small *bucket* made from 0.50 mm thick aluminium and a hole in the bottom. It is enough to do a proper job? Moot point now. I have to get it fixed, otherwise my U3 attachment will only serve as an expensive (US$80.00/US$125) paperweight. I have the notion that the *bucket* I make reference to could be drilled out and replaced with another one made from steel or phosphorous brass. The dovetail's smaller dimension is 14.30 mm so there's not much room (?) to make it of a larger diameter. I'll have to make a sketch and see what I can come up with. I'd appreciate any input on this from U3 owners who may have come across this same problem. Thanks in advance. Best, JHM |
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Re: Train Related?
Not an exhaustive list, but: Buy a(some)magazine(s) or book(s) Search online model engineers or model engineering groups. There are several at groups.io, and New England Model Engineering Society (NEMES) has a website that I know of.? If you're in central Oklahoma there's a group interested in models, ride-on trains, and real railroad trains that usually meets informally at Madison's Diner in Del City, OK. Saturday mornings upstairs at about 8am. There is probably a similar group somewhere near you.? I'm not particularly interested in models trains, myself, but it's a good bunch and several of them are also machinists, among other things.? Bill in OKC? William R. Meyers, MSgt, USAF(Ret.) Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY! Physics doesn't care about your schedule. The only reason I know anything is because I've done it wrong enough times to START to know better
On Sunday, August 21, 2022 at 07:28:15 AM CDT, OldToolmaker via groups.io <old_toolmaker@...> wrote:
Where would a beginning locomotive builder make a beginning?
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U3 top slide (part #150190) damage
Hello:
Once I cleaned up and checked movement and reversibility on my recently acquired 4-jaw chuck, I started off on making some flat stock from 10 mm brass stems/spindles I got from a chap I sometimes purchase plumbing supplies and kitchen/bathtoom fixtures from. He very graciously gifted me with ~ 1.5 kg. of various lengths which will be very useful.? 8^D But I digress ... As I took apart and thoroughly cleaned the top slide's aluminium body and inspected it, I found this: No need of a loupe to realise that the well that receives the M6 allen head bolt that screws into the 'T' nut in the carrier's slot to secure the slide in the desired position is cracked, no idea how this got this way. I had only put the slide in place once or twice to see how it would fit/work and as I found problems with the gib and the adjustment screws, put it aside till I could fix it properly. Is all this my own doing or is it part of this U3's history? After all, at serial #80070243 it has just turned 42 - ie: 80 => 1980 07 => July And just like health issues for us, stress/strain in metals is a fact of life. But I digress, again ... If I set the slide in its place on the carrier (without the bolt/'T' nut), I find that the deformation you can see in the photos does not allow it to turn freely or sit flat against the surface of the carrier, so this problem needs to be addressed, lest I put it in use and get this damn thingy flown into my face in the midst of a job. Evaluation: The top slide has a thickness of 8.00 mm: The recess in the carrier ie: where the top slide should sit and turn ~ 40¡ã CW or ACW, is a cylinder 2.80 mm x 12.00 mm: But the recess in the top slide's aluminium body ie: where the M6 bolt sits measures 7.50/8.00 x 11.00 mm. The 8.00 mm is where it has cracked open. It would seem that there is very little material (between the recess in the carrier and the recess in the top slide) to take the stress of the bolt securing the top slide in position. ie: Between the diameter of the carrier's recess and the internal diameter of the top slide's M6 bolt's recess there is only a 1.00 mm difference. If my math is correct, this means that the cylindrical *wall* of the top slide's recess has a thickness of only 0.50 mm. to take the stress of the bolt. Likewise, between the depth of the carrier's recess and the depth of the top slide's M6 bolt's recess there is only a 0.50 mm difference. If my math is correct, this means that the bottom of the top slide's recess has a thickness of only 0.50 mm. to take the stress of the bolt. So ... This whole thing is held in place by a small *bucket* made from 0.50 mm thick aluminium and a hole in the bottom. It is enough to do a proper job? Moot point now. I have to get it fixed, otherwise my U3 attachment will only serve as an expensive (US$80.00/US$125) paperweight. I have the notion that the *bucket* I make reference to could be drilled out and replaced with another one made from steel or phosphorous brass. The dovetail's smaller dimension is 14.30 mm so there's not much room (?) to make it of a larger diameter. I'll have to make a sketch and see what I can come up with. I'd appreciate any input on this from U3 owners who may have come across this same problem. Thanks in advance. Best, JHM |
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Re: Unimat 3 4-jaw options
If it's a 4-jaw independent jaw chuck, it does not? matter which jaw goes in which slot, as each jaw is independently adjustable. They are also often reversible. You will find it handy to have a pair of the adjusting tools. I found these instructions invaluable:?https://littlemachineshop.com/info/business_resources.php?ID=1343 Bill in OKC? William R. Meyers, MSgt, USAF(Ret.) Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY! Physics doesn't care about your schedule. The only reason I know anything is because I've done it wrong enough times to START to know better
On Friday, August 19, 2022 at 05:52:12 PM CDT, sawbona@... <sawbona@...> wrote:
Hello: On Wed, Jul 20, 2022 at 06:23 PM, @juliushenrymarx wrote: ... read good comments about Actools.Spoke too fast. Although they state in their eBay ads that they ship internationally and specifically to AR they do not. Started by asking for the exact address, then the province, then my shoe size ... Only to end up saying that DHL did not have a rep here and they could not ship the item to me. Not true as DHL, FedEx and two other carriers (which I did not ask for) have had offices here for over 30 years. So that was that with Actools. ... the one they sell comes from the same Indian OEM that manufactures ...I looked at all the Indian made options I found on-line again but the photos just did not convince me. They simply did not look right but I can't say exactly what it was. The Sherline is beautifully made but costs over US$130.00. All the India made versions, probably from the same OEM, cost between 40% and 50% of what the Sherline costs but I had already decided they were not an option for me. And I then came across a nice chap in Valencia who was selling an original and unused Emco 4-jaw for GBP75.00 on eBay. Very prompt and professional in answering questions and willing to work out the details as needed. Highly recommendable, I think. The GBP75.00 worked out to something like US$88.75 which is an excellent price, on the average just ~ US$25 over the cost of the non-Sherline options, so I jumped on it right away. I received it 20 days later in its well packed, original vintage/battered box: Complete with the original tool: There is no Emco? label? to be seen anywhere and jaws are not numbered, but it looks original enough: The internals: So that's another problem solved.?? 8^¡ã I? will be using it this week-end. Best, JHM |
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Re: Unimat 3 4-jaw options
Hello:
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Show quoted text
On Wed, Jul 20, 2022 at 06:23 PM, @juliushenrymarx wrote: ... read good comments about Actools.Spoke too fast. Although they state in their eBay ads that they ship internationally and specifically to AR they do not. Started by asking for the exact address, then the province, then my shoe size ... Only to end up saying that DHL did not have a rep here and they could not ship the item to me. Not true as DHL, FedEx and two other carriers (which I did not ask for) have had offices here for over 30 years. So that was that with Actools. ... the one they sell comes from the same Indian OEM that manufactures ...I looked at all the Indian made options I found on-line again but the photos just did not convince me. They simply did not look right but I can't say exactly what it was. The Sherline is beautifully made but costs over US$130.00. All the India made versions, probably from the same OEM, cost between 40% and 50% of what the Sherline costs but I had already decided they were not an option for me. And I then came across a nice chap in Valencia who was selling an original and unused Emco 4-jaw for GBP75.00 on eBay. Very prompt and professional in answering questions and willing to work out the details as needed. Highly recommendable, I think. The GBP75.00 worked out to something like US$88.75 which is an excellent price, on the average just ~ US$25 over the cost of the non-Sherline options, so I jumped on it right away. I received it 20 days later in its well packed, original vintage/battered box: Complete with the original tool: There is no Emco? label? to be seen anywhere and jaws are not numbered, but it looks original enough: The internals: So that's another problem solved.?? 8^¡ã I? will be using it this week-end. Best, JHM |
Bill in OKC too
OldToolmaker