Reamers only ensure that the hole is to size, location wise they offer no guarantees. Boring bar is the way to go when you need the hole to size and in the right place.
I work with cutting edge CNC machines and have access to any tooling I could ever dream of, yet I rarely do works that are as interesting and well thought out as this. You certainly have a vision and a way of achieving the results you're after with the proper means, all with humble machines, and a good mix of home made tooling (and tool!). This is seriously impressive for anyone passionate about restoring carburetors, as well as hobby and professional machinists. But not only that, the video is filmed with great skill. It is so difficult to film machining because of various reasons, notably lighting of highly contrasted shiny metal parts, chip management, focus, and knowing that you usually can afford one take for each operation. All in all the video has a good pace and excellent sound. I feel like I'm watching This Old Tony again, without the dad jokes. Keep it up man
a lot of machining videos on youtube show hobby machinists making a lot of tools, but usually they are making tools so they can make more tools without ever showing them making an end product with their work. It's very gratifying to see shop made tools put to a specific purpose, especially when done so cleverly.
It depends on what we’re doing. Sometimes I have to make a tool to make a tool, to make a tool. The end result is a tool to allow me to make a part that otherwise is too difficult, or complex to make otherwise. Sometimes I can make a tool to directly make a part. Most of the time I already gave the tools, or I just buy them. RU-vid requires people to make a fairly regular series of videos in order to make any real money because viewers want regular videos. So it’s a matter to come up with projects. A lot of people like to see tools being made. So I wouldn’t criticize either way.
I turned a female and a male taper much as you did here and they, as yours did, not match. Instead of remachining like you did, I used a grinding compound and lapped them to one another. The final fit was 100%.
@@nbrworks Good choice in general., Lapping tapers is tricky and generally doesn't result in a constant taper, because you can't move the parts axially so you end up with rotational symmetry and matching parts but not cones. Fine if you're making two parts to fit each other and nothing else, but no good for making anything interchangeable.
One thing that can mess you up on male/female tapers fitting properly is the cutting tool has to be precisely on center height wise. Most machinist are trained to run the turning tool just low of center height and a boring bar just a bit high on center. That will make the angle wrong. Some people know this and some do not. Just saying that is something I had to learn the hard way. Fortunately I was working at a job shop machining a big coupling to fit a tapered shaft so I got paid to do it wrong then got paid to do it right. Cost the boss man a $400 coupling.
I don't know how your channel escaped me for so long. I think your mix of tool making plus using said tool is perfect and this good balance might be unmatched on youtube. Thanks for the satisfying content.
I retired 6 years ago as a jig and fixture maker. I liked your video. I just wish I could have had the quality of tooling you have. The people I worked for cried like babies wen I asked for new or different tooling.
Very nice work. I once repaired an Obsolete Marvel Schebler carburetor for the engine of my brother’s airplane engine. Was challenging to say the least. I miss making parts for his home built airplanes.When he called me, I knew it was going to be something interesting.
Suspect part was rotated on angle plate and realigned for each bushing hole from the quill. A dividing head or rotary table required to achieve perfect alignment of the holes. ( you have an engine lathe and a knee mill, could build one. ) Side notes, Red Seal trade school hints from Canada: Hand hone rads on the corners of the cutting lip to lands on twist drill when the chisel point has no material to keep it centered, cuts smooth acting like a reamer. Blueing should never be smeared on full periphery, 3 equally spaced thin lines on taper angle and the mating part is twisted 1/4 turn max.
Awesome. Not really applicable probably since most people don’t have one on hand, but jig grinding these two bores would be the way to go to get them dead on in line with one another. I ran a Moore No. 2 at one point and super precise hole, slot, etc. location size and alignment were its specialty. Thanks again very glad to have stumbled onto your channel
A very thoughtful piece of work holding. If you intend to use the mandrel alot, have you considered drilling a hole at the root of the slits? If you are concerned with fatigue it would be a good idea. Thanks for the video.
24:45 This is PERFECT .. the idea that this tool can easily be used 1000 times, and never change accuracy or strength is very awesome!! In my opinion WELL worth all tis effort, the cost in materials is negligible too!!
Hi NBR, first time here, great to see you working so clean and precise. With interesting explanation and approach to all the aspects and problems of the job. Great video work also. Many thanks! Just one point . . . it would be nice I think to have some drawings or at least sketches, to follow along.
Great work :) , not being an engineer by trade you learn pretty quick its not the tools that cost but having the correct measurement tools so you can actually do stuff and then its endless if you have the skills (and the right lathe ofcourse) - Keep up the great work
Great work! when setting your compound angle, mount an indicator on the toolpost, square to the workpiece. You can then set your angle based on the travel of the indicator vs. the travel of the compound. For very sensitive angles, this will get you closer than the graduations on the compound can.
I imagine the reamer did deflect, when you where talking about at the end of the video. Have you ever put an indicator on the end end of the reamer while it’s chucked up in the spindle and touch it with your finger ?It’s amazing how much long tools can deflect and with such little force.
If you are getting long curly chips like that, increase the feed rate. This will usually cause the chip to break. Some materials are just hard to get a chip to break tho, and will naturally produce long and stringy chips, but usually increasing the feed rate will do the trick.
He sounds like a guy that's probably in a place that uses a lot of metric and British straight. British taper would probably be more common in EU than NPT. But I wouldn't know as I have never had to plumb in Europe 🤣 But taper threads definitely sounds like a better idea if he's not running an expander plug with a matched angle. Less work involved, off the shelf replacement parts.
With regard to the stiff shafting. Would they be smoother if you just drilled the shaft holes all the way through when removing the old bushings vs stopping before the bore on each side?
I worked in a tool shop for years. Next time you need to do a part like this (with open slots) I would put wax or a 24 hour epoxy. This will fill the slots and stop the tool from getting If you need the size. Make a ring to slip over it
You've done an amazingly beautiful job of both the internal collet and the finished carburettor! ♥ The only reason that I can think of for the brass rod sticking is that I think a bushing and the part passing through it are usually made out of dissimilar metals - e.g. steel and bronze, etc. - it may be that making both from brasses that are similar may cause problems. I sometimes use adjustable reamers that can be adjusted by maybe c. 200 μm or 8 thou - that lets the reamer be adjusted to get exactly the sort of fit that I want. I've heard of a soft wood rod or plastic rod being turned to the right size then used with some grinding paste as a hone to very slightly increase the diameter of a reamed hole and give a surface finish which holds lubricating oil.
I would just use some lapping compound. It's kind of a lousy set up, it has to be loose enough to pivot, but not so loose that air can enter the butterfly valve. Seems like it needs an o-ring somewhere.
you can def do this in a mill. you use something like a mitee bite ID expansion clamp. which is essentially the tool you made...but the mitee bites are flat on the bottom. for holding round parts in a mill :)
Those chips are dangerous. The solution is always to increase the feed rate, 0.3 mm/ rev is a good starting point and you can go much higher. This will also save time obviously. For a finish cut, leave about 0.3 mm radially (at least the amount of the insert's nose radius) and use a lower feed rate of about 0.1 mm/ rev. And please stay well clear of the machine especially with those long chips, once they wrap around the workpiece you can instantly get hurt very badly.
I had one long chip at the beginning and then played with it a little bit to see where it went. I was away from the machine and initially guided the chips to the floor, they weren't getting near the chuck (but it only takes a split second to happen, I know). I also don't usually take such heavy cuts. I tried to increase the feed but the motor couldn't keep up. For the next cuts, where the chips are breaking, I reduced the depth of cut. Anyway, thanks for the heads up, I'll be mindful of showing 'bad examples'' next time. Cheers
@@nbrworksalso, friendly suggestion, please don't use your finger to test surface finish while machine is running. Nice work, though, but there viewers who notice every little detail. Take care
If you bolt down the carburetor flange with the sticky shaft, does the sticky go away? Just a thought. I know with the aluminum LS block, the crankshaft is sticky until heads are bolted on. Great Video. I once dreamt of restoring vintage carburetors and now with a mill and a lathe you make me rethink having thunked it. Thank you
Aw man, a proper SU crate O.o SU's are still made up the road from me in Salisbury in Wiltshire and also cover Zeniths, Solex and other brands of vintage carbs. Do love old vintage crates and wooden boxes for putting stuff into, just adds a bit of gravitas to your stuff in my opinions :D
Quite an elaborate exercise. Your chasing microns in all of your work. The quality shows and I suspect you like to make accurate parts as a purpose. I also guess/hope that you will be using the steel mandril for more carburetors to come. I made a lot of expanding arbors for grabbing parts on a bore over the years. I made them out of aluminium because of the high friction coefficient. I turned the diameter close to the required size within 0,5 mm or something in the neighborhood. Drilled a hole, countersunk it and tapped a thread. Then I went to the band saw and cut four sections of 90 degrees each. Went back to the lathe and mounted a countersunk screw which I tightened lightly. Then I cut the diameter to size and mounted the part by tightening the countersunk screw. Real easy and fast like in 15 minutes or so. I saved quite a collection by now because it's easy to cut them slightly smaller for a new job. Don't re-chuck them for the same size because you'll end up with run out. Another nice and quick solution is the use of expanding sleeves on a hardened and ground conical pin. It's a commercial item and the pin is reused but the mating sleeve get's turned to size. One side in a collet chuck and the far end supported with a live center. Tap on the sleeve gently and turn it to size, mount your part and tap the sleeve towards the spindle so it expands. I have a collection from 4 to 10 mm which is quick and easy compared to making your own expanding arbor. Last but not least I own a set of Chinese C5 expanding arbors with imperial sizes. I'm a metric guy so I don't use them like so. I mount a sleeve with the inner diameter the same as the arbor. Tighten it a little (thin walled always) and turn the OD. Then I can directly mount a part on the sleeve and expand it with the C5 drawbar. Furthermore a reamer doesn't correct alignment much. It just follows the existing hole more or less. A long story but maybe there's something useful for the reader. Thank you for sharing your journey. For me it's my day job so I try to be precise the quickest I can ;-) Best! Job
Hi Job! Thanks for taking the time to write and share your experience and thoughts. I think I know the expanding sleeve/conical pin type of arbor you are referring to, but having a bridge (the bridge for the jet) in the middle of the bore doesn't help. Also some of these bodies have some steps machined inside, which limit the length the expanding "head" can have. That's why I made this tool, it ends up being very specific for the application. I count on using it in the future, the setup is very easy and I found to be repeatable. Not sure if you've seen that part, but I turned the final O.D. to size like you explained, with the arbor slightly expanded - that's to have a constant O.D. along the "head" when it is expanded to the desired dimension (the bore of the carb). I'm not a professional, I've been only using the lathe for around a year, so I'm learning. Again, thanks for giving useful feedback :)
@@nbrworks Major reconsideration about your video; if you're going to reuse the arbor on a regular basis it''s a valid explanation for the used material (steel or stainless) and all of the effort to be repeatable again next time. If it's just for correcting two carburetors I think it's over the top and an one ore two sacrificial aluminium ones would do the job perfectly much faster (and cheaper business wise). A true toolmaker knows when he can be rough and knows when he should be precise. A dear friend of mine is a toolmaker and rebuild his house by himself 30+ years ago. It took ages and his wife complained about the pace, To clarify; he used a caliper to cut his wooden window frames. That's exaggerating too; fit for purpose is the way to go. Best! Job
When your arbor expands do you get any issues with the sides not being parallel ie. tilted out? I would think with a ~10 inch distance between flange and arbor contact surface that would create quite a bit of play. This is why normally you would use 2 cones screwed on a shaft, one in each flange to keep the inner bore level.
Hi, the challenge with this tool was to make the sides parallel. Have a second look at 20:16. The ring shown is to 'lock' the jaws expanded (so they don't break) while I make the final passes and take the arbor to size. By doing that, I got the sides parallel when the arbor expands to 31.71mm. The end result of this is non-detectable runout and a very repeatable setup. If you look at the comparison done on the surface plate, I got each body parallel within 0.0005" (0.01mm) and that was after removing several times from the arbor to check the progress. That's why I say the setup is repeatable. Of course you can argue that 1 1/4 inches (the bore size) is closer to 31.75mm so there's theorethically another 0.04mm difference, but after averaging the bores with the internal micrometer I found out that 31.70 was actually the bore/arbor size. Hope this makes sense. Thanks
Both bodies were not originally a set, I'm pretty sure I have mixed up some parts looking for the best ones to make 'my set'. But looking at them I wouldn't say they had 0.5mm (actually more) of difference. Some of these bodies don't have a take off for the distributor vacuum and others don't have a way to mount the choke lever cam, that's why I mixed and matched until I got what I need. Thanks!
I would have kept the old bushes and turned 2 o ring grooves on the shaft. Do you have the flexible link to join the shafts? It would have been a good idea to keep the pistons and dashpots that were matched to the carb bodies together.
The shafts are linked using a pair of couplings, have a look at 31:17. But I think I know what you mean by flexible link, I have some H1s (1 1/8") that have a flexible link, but not the H2s (at least not the ones I have). The pistons I'll be using will not be the originals - I'll be using the quick lift type. Thanks
It does need an o-ring in the mix, how can a shaft be loose enough to pivot, but not so loose that air is allowed to leak in?? Unless it's factored into the jetting, I'd think it would be far more relaible with a seal of some type.
Originally none of these types of carburetor have seals. That's why it is so important to have as less play as possible. Look up for h2 or hs2 or h4 (bigger size) diagrams on google - you'll find exploded views with all parts.
Can you imagine the cost of what you just did, if you were charging for a one off part restoration? E.g., I just restored an old Minolta camera, it took me 25 hours to complete and for that I didn't need to make any parts. The camera cost me £23, the best price I'd get for it would be around £100, so at a modest charge rate of £25 / hour, that would be £625, that's £525 more than the camera is worth.
Hi, this is not customer work, I did it to enjoy myself. But I'll bite (in a good way 😀 ). I took 17 days to make this tool and the dog driver in the previous video. Some nights and a few weekend days - because I have a different full time job. I can't give you the exact number of hours, but let's say it was 2 hours per night (it wasn't) and 12 hours on weekends. 54 hours at 25gbp/hour that's 1350gbp (which isn't fair because I spend a lot of time setting up the camera). Add 10gbp for materials. Maybe more 20 to account for the bushings and the specific 5/16 long reamer that I bought second hand. Sure there's a huge initial cost, but what about this? - The repair of an H2 carburetor is currently at 300gbp + VAT, each!! Source: www.sucarb.co.uk/restoration-prices - Rebushing is 80gbp - not sure if that's included in the 'repair service' - Labour is at 70gbp/hour, again not sure if included in the repair service - With the new tool I can reface both carburetor flanges in 10/15 minutes max, accurately and in a repeatable way. - That added confidence for my rebushing and learning process - Like I've shown in the video, I might be restoring a few more sets. Maybe 10? 15? To me I feel like this was worth it. Starting with satisfying myself because I wanted to take the challenge. In terms of business, I understand it might not be worth it. Hence the title of the video 😅 But these parts are not cheap to repair and there's another important aspect - some of them are quite rare, so it's better to avoid mistakes - that's also why I don't mind having some trouble once in order to simplify future repetitive work. Hope this makes some sense! Thanks
That was some nice machining, parts turned out well, far better than the original manufacturer ever considered possible. I am a little surprised you didn't radius all the internal sharp edges while you were in there with flex shaft grinder? Back in the day it was much more common to have sheet of emery paper on a flat surface to correct bow on flanges, exactly how you did it. Milling machines were a 'luxury' few shops had and cost at machine shops was far too high for majority of people. There were aftermarket kits for the bushings, just drill them out and hammer them in (then spend time with a file and emery cloth fixing the burrs). I imagine they have been out of production for 50 years or more by now though? You should have drilled holes at end of expansion slots, it would mean there is less material to flex. You could still do it but will need to use a center cutting end mill. Using Morse taper adapter as an extension for center may give more clearance but it's going to be very flexible when you have any side loads (as in turning) and probably reason for chatter? All in all, a very interesting video. Are you (or have you) done a video on rebuilding the SU carbs? I had them on my first car (1966 Rover)
Hi, nice to have you back! I might add some small radius in certain points, but I want to do it carefully and focused, not in an awkward position with the camera in the way. I believe Burlen in the UK still sells service kits. I have one I bought several years ago, it came with steel bushings, coated with teflon inside, but in my point of view, they leave a little bit too much play for the shafts. That's why I didn't use them. I also believe Burlen replaces them, as in a service they provide, but I don't know details about that. Regarding the holes at the end of the expansion slots, I will do them, like you say, plunging a center cutting endmill, this was also suggested by other viewers (thank you). The morse taper extension... it's a good point. I bought the extension because I needed the clearance, but I also thought it was going to flex a lot and be unreliable (or reliably give bad results). But in fact, I can't complain. At 2:02 there's an example of that. Until something changes, I'd say that extention is working for me. At least it's better than having the tailstock fully extended 😉 Video with the full rebuild of the carbs... no, I haven't done that yet. I still need to take care of some things first: pistons and chambers, choke mechanism (I need to invent something to make it work), take care of the manifold, air filters, etc. But I'll make that video, that's guaranteed. Thanks!
31:24 I wonder if an 'oldham coupling' would be a good choice for this, unless it needs the 'give' and spring the metal can provide. But it just seems more built to cost. Also modern day 'spring couplings' like those used in 3d printers could have those properties and likely better concentricity.
Yes, there are better functional choices, but something I didn't mention in the video was 'looks'. Being for a classic car, I'm trying to keep these carburetors 'in period'. That actually influences a lot of decisions. Thanks!
Great video showing interesting techniques etc. But this is overkill to replace the bushings. It does not matter if the mounting faces are perpendicular to the bore or not. It does not matter if the two mounting faces are parallel or not. In this instance all that is required to achieve the end result was to use the same technique used at the 26:22 mark. 😁 Mounting and packing to align the pin. Having said all that it is still a great video showing useful techniques to others so well done 😊👍
What about a press fit shaft installed with thermal expansion? I would imagine the aluminum carb would expand quicker than the stainless rod so a quick hit with the torch would release it.
great work again, thank you very much! 👍 why did you use such a long boring head to bore the bronce bushings and the chamfers...i would be afraid of chatter...although they came out great, so what : )
Hi, nice to have you back! It was a matter of using what I have available. The boring head takes 12mm tools. I don't think I have any broken tools with 12mm shanks (to grind), and the 6mm boring bar shown at 8:16 looked perfect for the job, including the 12mm sleeve (coincidence?). I thought of cutting it in half, but not without trying it first. And it went well for the boring. For the chamfering I seriously considered cutting it, also because the carb body is very long, hollow, and was only clamped at the bottom. But the tool was sharp and I gave it a go. If you look in the video I didn't let it rub, I was quick to feed, let it cut and retract immediately. I think that if I let it rub it would chatter. I definitely need to get a shorter sleeve though.
at 5:15 a great tool, but maybe try a different tack, aka use a split collar, on this arbour, and have the arbour undersize, so a bush and tapered ends fit on, and a shoulder on one end, and a nut, they tighten and expand the sleeve, tightening the fit. another 'turn key' solution uses a rubber material which expands on tightening ( on press brakes, and such, for pipe working), maybe the way to go?- to have a more solid core, and adaptors, rather than putting all the force onto a smaller thinner part?
Great video. I have been doing exactly this for about 25 years now. I repair old engines and I have the same issues. I use two tapered cones and put them in both ends to self center. Like you said, flat but not surface plate flat.
Expertly machined to some AMAZING tolerances!!! Based upon my own (heavily limited) experience, that's just plain WRONG for an SU carbie... (They come from the FACTORY with 2mm differences in venturi sizes!) Once again though... WELL DONE!!!
If you had one of the hobbyist wire edm machines you could have cut that expanding head without a care in the world. Only run about $1000 for a 3 axis 10 gallon fish tank setup and probably be invaluable for tricky fragile cutting
Maybe I didn't understand the arbor design, but if it is expanding only on one side, how much contact it gives with the bore? Seems the bore will only be griped by a small portion at the front, which might get the part not to be aligned properly. Again maybe I didn't understand how the arbor works.
Hi, I tried to explain in the video, but maybe I wasn't clear. I'm sorry for that. Your reasoning is correct, have a second look from 20:06. I made 2 light passes with the arbor expanded until I reached the desired dimension, which was an average of the bore sizes (checked using the micrometer). That's what I am measuring at 21:20 - the arbor is 'straight' when it is expanded to 31.71mm. These last 2 cuts were the challenge of making this arbor and why I used that ring to make it solid (so it wouldn't break). Hope this helps. The setup is very repeatable - I was surprised by that!
@@nbrworks It had a taper for it's whole length and the slots were cut much like the slots of a ER collet. The plug went almost all the length of the arbor, so when tighten, both ends would expand. It worked very well for the purpose I made it, but was a pain to make (an enjoyable pain though)...🤩
My friend let me tell you you take this part without the ring diameter make a matching plug using the same angle. You may wish to use a shalower angle but nothing less than 10 deg and take your plug much deeper into the mandrel don't neck it down so much unless you must where ever the relief is you must take the saw cuts into the relief You can apply the expansion plug utilizing your Live center and pull it out with what we call a Russian hammer a puller. Use a heavy Molly Grease the key to this whole thing finish all your diameters you cut the mandrel slots on a band saw last deburr neatly with a small Jewelers file. If you have a nice diameter it's easy enough to re indicate in especially if you dump that three jaw Chuck and only use a four jaw if you think about it it is so easy do not let it scare you 3jaw chucks are lame inaccurate even I only use them for soft Jaws where we us a setting ring or mandrel and then they are cut to suit the part. Looking at your part is almost perfect as long as it's bigger at the big end that is all that really does the pushing I think your angle is too sharp and the entire mandrill is too short try boring almost all the way to the shoulder leaving only a small amount like maybe a quarter inch wall to do the actual outward movement
The easiest solution you make your mandrel drill a small hole for your pipe tap use a pipe tap reamer and tap deep enough to apply half of the tapered pipe plug. you use a tapered pipe plug to open the mandrel but again you must finish all your diameters when it is solid drill and tap the pipe plug thread use a bandsaw to cut the slots last debur very carefully with a small Jewelers file and fine sandpaper. Done easy peasy
