Stuart 10V Build Log – Complete Beginner…

[John ATTLEEParticipant @johnattlee20632]

This does not look like the work of a "complete novice" to me!

John

[Jon CameronParticipant @joncameron26580]

Posted by Dr_GMJN on 21/05/2020 23:20:23:

Posted by Mark Gould 1 on 21/05/2020 22:30:07:

Your progress looks excellent! I did started my first Stuarts 2 years ago and have only just completed it. Go slow and it'll turn out beautifully. You seem to know what you're doing so no worries there

Mark

Ha ha thanks Mark – too kind; if you look at the beginners section of the forum I think it’s clear I don’t know as much as you think! Cheers!

Mark,

If I could make a suggestion, (well a request even). That any of the "beginner" questions about machining the 10V you ask in the build thread. There is a lot of very useful information that will possibly be lost now into the depths of the forum that is very relevant to this thread. I always find that I learn more from a build thread, not always about how to do right, or what it looks like after the machining has taken place, but rather how not to do it, when things have not gone to plan how to correct those mistakes. There is a lot on setups, and machining steps that may be lost out on also. Having questions relevant to this build, included in the thread is a good way for a novice builder of the 10v to learn themselves and it will also inspire confidence to carry on knowing that yes mistakes happen but these are ways to correct it.

I'll keep following the build as I possibly have x2 10v and x2 10h incomplete sets to build soon, so I am also picking up tips from your thread, and the other questions posed elsewhere. My worry is that a new person viewing this thread will loose out on all that good advice in the future. This is turning into a good build thread, and that is my only suggestion to make it even better.

Jon

[JasonBModerator @jasonb]

I'll second that and had earlier moved the post at the top of this page from another thread, with the current amount of forum traffic it is hard to keep track of things.

Edited By JasonB on 22/05/2020 08:50:59

[Dr_GMJNParticipant @dr_gmjn]

OK guys – understood.

TBH I thought the other way round was better when asking for advice – eg about drilling the bearings, becasue if people don't happen to look at the build thread I won't get any responses?

[Jon CameronParticipant @joncameron26580]

Posted by Dr_GMJN on 21/05/2020 23:10:19:

So I’d like to get on with the bearings – plan is to face the brass, Figure out the centre point, punch it, then set up in the 4 jaw Chuck to run true. Then gradually open up the hole and hope the drill doesn’t wander. Question is, for a finish diameter of 9/32”, eventually line reamed in-situ on the sole plate, what is the largest drill size I should aim for on the lathe?

For final reaming Id use the mill, with the largest drill used to line the sole plate/bearings assembly up on a 90 degree block.

Nothing wrong in that logic, to answer the question of drill size, if it was me doing it i'd drill it big enough that I could get my boring tool in the hole and then a little wiggle room too for clearance. Then use the boring tool instead of the risk of taking too much off the bearing by a drill wandering off course.

Jon

[Dr_GMJNParticipant @dr_gmjn]

Posted by Jon Cameron on 22/05/2020 10:01:04:

Posted by Dr_GMJN on 21/05/2020 23:10:19:

So I’d like to get on with the bearings – plan is to face the brass, Figure out the centre point, punch it, then set up in the 4 jaw Chuck to run true. Then gradually open up the hole and hope the drill doesn’t wander. Question is, for a finish diameter of 9/32”, eventually line reamed in-situ on the sole plate, what is the largest drill size I should aim for on the lathe?

For final reaming Id use the mill, with the largest drill used to line the sole plate/bearings assembly up on a 90 degree block.

Nothing wrong in that logic, to answer the question of drill size, if it was me doing it i'd drill it big enough that I could get my boring tool in the hole and then a little wiggle room too for clearance. Then use the boring tool instead of the risk of taking too much off the bearing by a drill wandering off course.

Jon

Thanks Jon,

Looking online, it suggests using a 7mm hole to give a 2% undersized hole for reaming. So that's about 0.0055" remaining for the reamer to remove.

I'm still concernd about drilling/boring the brass. Would it be better to do it from one end, or drill both ends, with the final passes of the boring bar from one end? My thinking is that any initial wandering effects would in theory be halved that way. The other option would be to split the casting into halves before boring, but I think that might give me different problems.

Is my method of final reaming sound, ie mount the bearing blocks in the sole plate, then mount the assembly vertically, align with the mill spindle and ream vertically through both blocks?

Cheers.

[Jon CameronParticipant @joncameron26580]

Hi,

If I could direct you to Harold Halls page HERE, you'll see the best way i think to machine the bearings, cut them into two sections, mount in 3 jaw, with packing to protect them. Drill and bore, then mount onto a mandrel between centres for the boss to be turned to size. The bores are left undersize to begin with, they can be line bored to set the correct alignment once bolted into position.

So yes bolt to the bedplate, then finish to size when all bolted together. It may well be prudent to gently centre punch the bearing and bedplate so that going forward to finish the build when they are taken out or put back together they always go into the correct place, and your not chasing your tail looking for fault when you assemble a new part thinking something isn't correct with it. (do it discreetly on the inside of the bed plate and bearing. one dot for left side two dots for right side).

Jon

Edited By Jon Cameron on 22/05/2020 11:26:36

[JasonBModerator @jasonb]

yes, definately cut in half and treat as two items for initial work, back in the day a 1/64th" smaller drill would have been the most likely used, I'd most likely reach for 6.9 or maybe 7mm with the 6.9 being first choice as a drill can often cut oversize. Once upto 8mm hole I tend to bore on the lathe rather than ream so drill wander is eliminated, you could just about bore to 7mm if you have a small bar.

The other option would be say drill 5mm, put a 6mm or 1/4" milling cutter through held in the tailstock which will true up your hole and then follow that with your reaming size drill that will then have a straight path to follow.

[Dr_GMJNParticipant @dr_gmjn]

OK great, thanks guys.

I'm going to put the pieces in my 4 jaw chuck, and use a piece of steel with a point on at one end (into the centre mark), and a centre hole at the other, to get it to run true with a DTI "between centres" as it were. I've seen this done online on these bearings I think.

Any advice on what to use for the indicating rod? Can I make one, or use some other bit of equipment?

Cheers.

[JasonBModerator @jasonb]

It's not critical just whatever you have, I've made a sprung one which stays in place a bit easier but plain will get you started.

[Jon CameronParticipant @joncameron26580]

Posted by JasonB on 22/05/2020 13:14:32:

It's not critical just whatever you have, I've made a sprung one which stays in place a bit easier but plain will get you started.

Sometimes, just sometimes, I overlook the blindingly obvious! SPRING! another to add to my to do list. Thanks Jason.

[Dr_GMJNParticipant @dr_gmjn]

So today I re-made the spot facing tool, this time in Silver Steel from M-Machine, rather than Stainless (which I used by mistake last time). I've put all my known and marked steels in a box, the rest I've kept in reserve in 'deep storage' (the shed) just in case.

Made a jig (thanks for the ideas Ron and Jason) for the milling machine to make the tool more acurately than I could by eye:

Then hardened by getting cherry red and dunking in brine:

Made another spigot, brass this time, to keep everything concentric:

The test:

Perfect!

Thanks for the help, and bearing with me on the spot facing issue – got there in the end!

Also separated the main bearing stock and faced them off with my new ARC premium mill, which performed beautifully:

So a bit of progress I think. Cheers.

[Dr_GMJNParticipant @dr_gmjn]

Posted by Jon Cameron on 22/05/2020 11:21:44:

Hi,

If I could direct you to Harold Halls page HERE, you'll see the best way i think to machine the bearings, cut them into two sections, mount in 3 jaw, with packing to protect them. Drill and bore, then mount onto a mandrel between centres for the boss to be turned to size. The bores are left undersize to begin with, they can be line bored to set the correct alignment once bolted into position.

So yes bolt to the bedplate, then finish to size when all bolted together. It may well be prudent to gently centre punch the bearing and bedplate so that going forward to finish the build when they are taken out or put back together they always go into the correct place, and your not chasing your tail looking for fault when you assemble a new part thinking something isn't correct with it. (do it discreetly on the inside of the bed plate and bearing. one dot for left side two dots for right side).

Jon

Edited By Jon Cameron on 22/05/2020 11:26:36

Jon, I’ve read Hall’s method, but it’s a bit vague fair a beginner wanting to replicate it. For example – mounting on a mandrel – how to you stop the part from turning?

Also, when assembled, the inner boss faces seem to provide the crankshaft end-float limit; am I better off leaving excess in the inners, and then finishing them to the crank web width later on?

Thanks.

[Dr_GMJNParticipant @dr_gmjn]

Still puzzling over how to retain the bearings on a mandrel and how to make a centering bar, so in the meantime I thought I'd finish the box bed. The mounting lugs are cast with dimples to drill to, but they didn't look central to me, and since thre are no dimensions given on the drawing I just got one with it the best I could.

I trued the casting up with a DTI along its long egde, and then milled 0.8mm off the top surfaces of the mounting lugs. I used 0.2mm cut depths. I did the side-to-side cuts by eye. A 12mm end mill covered the width of the lugs in one pass.

I wanted to get the mounting holes concentric with the end radii of the lugs, and since the cast radius doesn't cover 180 degrees, I opted to find a washer that was a good fit, and measure the diameter of that:

Then a fairly simple task of finding the middle of the casting, and using the edge finder to find the apex of the radius, then move to the centre using the DRO, centre & and drill to 3.5mm diameter:

Worked OK:

Pretty basic stuff, but one step further on.

[Martin ConnellyParticipant @martinconnelly55370]

Turning between centres using a mandrel requires a tapered mandrel. You can make your own, the taper is created by setting the tailstock slightly off centre. There is a standard taper for such things, it is a few thou per inch but I can't recall the proper value as I have not made one or used one. I'm sure some in the forum have made them but a google search should turn up an answer. You can also get expanding mandrels but they are only worth buying if you are going to use them a lot or can get them cheaper than a bit of bar.

There will be instructions on using them somewhere on line but basically push the part down the taper until it locks in position. Big steel parts could be heat shrunk on or hydraulically pressed on or off. Small brass parts a gentle tap should be all that is required but don't take deep cuts. Also the direction of cut should be the direction that pushes the part further onto the taper.

Martin C

[JasonBModerator @jasonb]

For small beaings and such parts like this your arbor or mandrel can take many forms.

1. Most simple is to put a piece of bar into the chuck and turn to a good firm fit in your bearing and then slip the bearing on with a small amount of loctite or superglue, once machined heat will break the bond. The downsid eto this method with four ends to do is that you have to remove the mandrel each time to heat, it can be marked so it goes back in the same way but not ideal to remove it.

2. Similar to above but turn the spigot that fits into the hole about 2/3rds its length but put a very slight say 1 deg taper on the rest so the diameter increases towards the chuck. You can then slip the bearing onto the parallel part and then wring it onto the taper with a slight twisting action, if light cuts are used it will hold and the part can be wrung off again so mandrel stays put ensuring it's concentric.

3. Again turn a spigot to a good firm fit in the bearing and just shorter than it then drill and tap the end for a bolt or screw to retain the bearing, M5 with a cap head screw would work nicely on these bearings as screw head is just under the diameter you want to turn. Again mandrel does not need to come out of chuck. I'd go with this option.

4. Turn spigot to full length or a bot longer, drill and tap with a taper tap so you get a few full turns of thread. Mark the bit of bar you are using so it can be removed from chuck and then saw down the middle of the spigot before putting back in chuck. You can now slip the bearing onto the spigot and wind in a screw which will expand the spigot as it gets to the tapered part of the thread.

I tend to use aluminium for these sort of things and you soon build up a collection that can be used again and again, maybe skimming down to the next size or shortening.

[Dr_GMJNParticipant @dr_gmjn]

Thanks guys – that should see me through a good few steps.

[Ron LadenParticipant @ronladen17547]

Posted by Dr_GMJN on 23/05/2020 17:28:17:

Still puzzling on how to make a centering bar,

If you go to Stationary Engines and find my Rons Jowitt thread go to page 2 and you will see Jason's pictures of his Sprung Indicator Rod both the parts and how to set it up and use it. There is also a drawing which he kindly sent. We'll worth making, I have used mine quite a bit.

I must learn how to make and add links.

Ron

[Dr_GMJNParticipant @dr_gmjn]

Posted by Ron Laden on 24/05/2020 06:00:43:

Posted by Dr_GMJN on 23/05/2020 17:28:17:

Still puzzling on how to make a centering bar,

If you go to Stationary Engines and find my Rons Jowitt thread go to page 2 and you will see Jason's pictures of his Sprung Indicator Rod both the parts and how to set it up and use it. There is also a drawing which he kindly sent. We'll worth making, I have used mine quite a bit.

I must learn how to make and add links.

Ron

Thanks Ron, Jason kindly pm’d me a as link to that. I’ll put it here next time I update it. I might try making something similar today.

I should also probably make adjustable saddle and cross-slide stops for the ML7 too at this point.

[Dr_GMJNParticipant @dr_gmjn]

So thinking about the process of machining the bearings – I’ve got to turn bosses of different lengths on each end. It’ll be an intermittent cut from the outer ‘wings’ to the solid inner, so I’ll be moving the cross-slide in, cutting towards the Chuck, backing off, then incrementing the cross-slide in again before making another cut towards the Chuck.

Trouble is, I need to make the cuts to the same length towards the Chuck, and I have no limit stop. I spent most of yesterday’s hobby time making one that screws to the headstock on the lathe. It’s mode of scrap aluminium and some 304 stainless rod. I found a spare quick-release toggle, so decided to use that as a clamp, rather than threading the bar. I did add a cap head screw and lock nut to the end for fine adjustment though. It took a long time to make, mainly because I made it up as I went. I should have drawn it all out, but sometimes that’s the way it happens:

One lesson learned was that accurate alignment in every axis is critical for for consistent chamfering…next time I’ll get it better.

Now for the sprung centering rod…

[JasonBModerator @jasonb]

I just set my topslide in line with the lathe axis and use the handwheel dial to set depth, touch the end of the work, zero the dial and away you go. I only use a stop on odd occasions such as a long blind bore.

I think the myford has the option to engage the half nuts and use the handle on the end of the lead screw as another option.

[Jon CameronParticipant @joncameron26580]

Posted by JasonB on 25/05/2020 13:08:21:

I think the myford has the option to engage the half nuts and use the handle on the end of the lead screw as another option.

Correct however disengage the banjo and change gears first. Sounds obvious but I've done it three times now setting up to machine and broke the sheer pin on the leadscrew on my ML4, simple fix but directing I'm obviously a slow learner haha.

[Dr_GMJNParticipant @dr_gmjn]

Jason, Jon,

My ML7 doesn't have dials I can zero, so I always have to remember the setting and how many turns I've backed off. If I go over the setting (or forget it), I get a step in the work. It's not great tbh. As a beginner, it's easy to turn a wheel the wrong way and really mess something up (ask me how I know!). I was going to upgrade to re-settable dials and thrust bearings, but I think I might just fit the bearings and a pair of cheap DROs (as with my mill) – everything seems so much easier with them, with no backlash to compensate for.

Yes, I can engage the leadscrew half-nuts and turn the handle at the tailstock end, but then I'm trying to keep to a figure on the dial at one end, where I really want to be looking at the workpiece at the other.

Anyway if my saddle stop doesn't work, I'll use the 'remember the setting' method I suppose. Building this engine really highlights what modifications would be useful to my lathe.

Cheers.

[Dr_GMJNParticipant @dr_gmjn]

Anyway, cracked on with making a centering rod. I made it out of the remains of the 10mm silver steel I got for the spot-face tool, some brass off-cut and a random spring.

I 3D modelled this time so it only took a couple of hours to make. When it was assembled, I was a bit alarmed at how sinister it looked.

I noticed Jason's version had the point sprung loaded, but I wasn't confident I could make a perfect sliding fit (no reamers); my thinking was that any play in the pointed end might interfere with the DTI reading more than if the play was at the back, because the back isn't side-loaded by the DTI. Anyway, in the end there isn't any discernable play in the plunger.

Not sure about the cone angles, but I suppose I’ll see if it works soon enough on the main bearings…

Cheers!

[Dr_GMJNParticipant @dr_gmjn]

Marked out the centre of the bearing with caliper lines scribed on some blue marker. I had to use an eye loupe to get the punch central – my eyesight certainly isn't what it once was:

Next thing is to mount them in the 4 jaw chuck and align them with the centering rod.

Trouble is, the drawing seems to be wrong: It calls for the bearing width to be 7/16" (11.11 mm), but it's not that to start with – it's only about 10.95mm (hence me buying the wrong sized ball-nose mill). It then calls for the bosses that protrude from this to be 27/64" (10.72 mm) in diameter. So that only gives about a 0.12 mm wide step around the boss – totally out of proportion to the drawing; it should be approximately double that. I guess I could use the calculated step width from the drawing, but then that eats into the bearing face area of the bosses.

I wonder if the drawing is wrong, or they've changed the dimensions of their brass castings?

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