Bolton BT800 and AT750 difference?

[aPpYe]

Hello, up front, I have zero machining experience. Not even back in high school. I have watched some youtube videos, and I know some of the things that I want to do with a lathe and a mill/drill. Currently, all I have is a drill press and an off brand dremel. And a bench grinder.

I am seriously looking at getting a 3 in 1 ... I have read all the caveats about them lacking rigidity in the mill, irritation changing modes, poor accuracy compared to industrial machines used by professionals, etc. Are they any less accurate than the Sieg mini lathes and machines I was looking at a few days ago? For the sake of this conversation, let's assume I am sure these machines would fit my needs and my budget. They are much bigger than the mini machines I was looking at before. Specifically, I am looking Bolton machines, partly because I can save on shipping by picking them up locally when I visit Los Angeles after the new year... I see that the AT750 is a clone of the Smithy Midas 1230 LTD (is the Smithy the "original?") ... I also see that the BT800 is essentially the same machine as the Grizzly 9729 (not sure what these are modeled on, is the Grizzly the "original?") ...

Bolton has these machines both listed at the same price ($1870.06). At first glance, I would think that I would want to choose the BT800, as it is a bigger machine, with a 16" (vs 12") swing. The fact that they are listed at the exact same price gives me pause. I am wondering if there is some inherent superiority to the AT750? I was hoping someone could share some thoughts on why I would choose one of these two machines over the other.

Also, while I am sure that all of these vendors (of machines likely all imported from the same Chinese manufacturer) claim that they are better than the others, Smithy states these claims rather aggressively, "All of these machines are of inferior design and manufacture - built to sell cheap and generally having a variety of quality problems." ... Anyone want to chime in on these claims? Their price is not too much higher, but that $249 shipping fee could be applied to some tooling or something on a Bolton...

Thanks for your time.

 

[tweinke]

Here is my two cents worth, Smithy appears to have decent support after the sale I would poke around a bit a bit to see if Bolton offers support. As far as the 3in1 machine with patience and creativity it will make good parts. I would make sure the work envelope for both milling and turning meet your needs before purchasing. Also what accessories come with the Bolton machine are they all extra charge vs Smithy with there included tool pack. I have a mid 90's Shoptask 3in1 and if not for it I never would have gotten started in this hobby. I personally think with creativity and understanding the limitations of the 3in1 machine you can have a lot fun learning. As far as accuracy a lot of that is operator understanding the machine. It definitely is not going to hog metal like a K&T mill or a 16x40 lathe. As far as quality of each machine I suspect that there is to some extent different levels based on what the seller is willing to pay. Also plan on tooling you will need to use the machine, and I would recommend HSS for boyh lathe and mill tooling. Not very hard to learn to grind lathe tools and HSS end mills etc can be had reasonably. Notice I didn't try to talk you out of the 3in1 machine just because it is what it is. If you care I added a stand alone bench mill to my shop after the fact only because I was not satisfied with the mill portion of my machine. Hope at least some of this is useful to you!

 

[aPpYe]

In fact I did notice your refrain from trying to talk me out of it ... I was half expecting page after page of people steering me clear of them! What got me on to this idea was the size of the lathe compared to the mini lathes. I have a budget of around $2000 and am trying to decide between a 3 in 1 or a mini mill and mini lathe. How does the lathe portion of the 3 in 1 compare to 7x mini lathes, accuracy wise? I see a lot of talk about power and taking big cuts, but I really don't care about that at this point. I don't mind taking many smaller cuts to get to the same end result... Again, I am completely inexperienced so perhaps that is an ignorant statement.

This is 100% hobby stuff. If I can fabricate something that will help me with actual work around the house or to help a buddy or something all the better.

I am kind of rambling. My thought process right now is if the lathe portion of a typical 3 in 1 stacks well against say, a Sieg C3 or an LMS 5100 (both 7x mini lathes) accuracy wise, then I might as well go for the 3 in 1 for the size of it and live with the limited milling capabilities for now, and get a mini mill down the road if I am so inclined.

 

[tweinke]

Accuracy should be better then the 7x lathes in my opinion. I think that even though the lathe portion of the machine is pretty fair due the compromises to make the machine for multiple tasks it does have some issues with rigidity. Once you learn the limits as far as cut depth and a bit of tool geometry it can work ok. I think that due to the height of the tail stock, the height of the compound, and even the headstock is where some of the "flex" in these machines comes from. Like I said once you learn what the machine likes you are pretty good to go. Now I'm going to push my luck with you...... are you sure a G0602 lathe and maybe a G0704 mill or the like wouldn't fit the budget, you may be happier in the long run. But in all reality if this is the way you go it can absolutely do good work you may need to be more creative with setups but that may help you in the future. I think figuring a good and safe setup to be part of the fun of this hobby. Before I got my 3in1 I did look at a 7x lathe and boy is that small compared to my Shoptask

 

[aPpYe]

Morning. I was looking at that lathe last night. The thought was to pair it up with a mini mill like a Sieg C3...

Is that the basic idea with the accuracy of these machines then? Take lighter cuts and I should be fine accuracy wise? Let me ask the question a different way: Let's say I am very patient, and I have all the time in the world to create an aluminum shaft that is exactly 4.000" long and 1.000" diameter with a piece of 1.5" bar stock. How long would this take? What kind of precision can I expect along the length of the shaft? Also, let's say I want to run a 2.000" channel along the length of the shaft, precicely .250" wide and .100" deep. Let's also throw a .125 hole through the whole thing, precisely centered at both X and Y of the channel. What kind of precision can I expect to achieve here? Again, I don't mind taking my time and taking small cuts, etc. What about the same project with steel? This is not any project I have in mind, just a hypothetical thingus I am making up to try and get an idea of the precision these machines are capable of. Would the separate lathe/mill combo you mentioned be capable of better precision on the same part, assuming time is not an issue?

Right now, the only real project I have in mind would be to do some valve work, possibly turn a hammer/striker and some spring guides for my airgun. Now that I think about it, I would also like to fabricate brackets and maybe a pulley for an automotive engine swap project I have going. All of this (with the exception of the pullies) would be fine on a mini lathe and mini mill, as the parts aren't that large, and there is no real need for industrial strength precision with any of this. I do like the idea of some light gunsmithing, but no real barrel work other than perhaps light recrowning... I will probably use the machine(s) to do some work on my R/C cars... Beyond that, household projects and whatever comes down the line that piques my interest. As far as milling work, I really never gave it a whole lot of thought, as the original idea was to get a 7x lathe and a milling attachment for tiny milling work. All of this would pretty much be for futzing with my hobby stuff, with no need for production level speed or anything business related...

 

[tweinke]

Well the accuracy part will mainly be up to you and I think unless you are shooting for aerospace tolerances you will be fine. For me I shoot for what the project requires tolerance wise and generally if I fall out of that range its all me not the machine. I think thousandths pretty easy ten thousandths a bit harder. Your hypothetical part would not be any problem time wise I think I could do that in an hour or so figuring set up time and not trying to hurry. Aluminum turns pretty easy and for me .040-.050 roughing cuts are doable (.080-.100 off diameter) .250 key slots probably can be done in two possibly three passes figuring .125 deep like a key slot. the hole is a piece of cake being you will already have the part in a milling vice and centered or if through the long way in the lathe chuck. Mild steel would just mean a bit lighter cuts. For me its not about the time because I enjoy the work/setup. Just a thought to throw into the mix not trying to change your mind on the 3in1, QMT sells a nice 10x22 lathe and a nice small mill. would blow your budget by a bit for the individual machines but convenience wise would be really nice feature and warranty wise. ( Precisionmatthews.com). Don't forget you will need tooling and measuring instruments also which can add up cost wise pretty fast. Just trying to be helpful not overbearing!

 

[aPpYe]

I absolutely appreciate the information. Keep it coming! Not overbearing at all.

Looking up QMT, I came across sites that had smallish industrial caliber machines, and some other sites that had stuff only billionaire corporations would have. Precision Matthews had machines of my caliber, but they start pretty far out of my price range, with the cheapest lathe and mill coming in at $3500 together. Aint gonna happen, unfortunately!

I guess I am back to trying to figure out the difference between the AT750 and the BT800, then also deciding if I want to go for the smithy midas 1230... One of the things I thought might be fun would be to learn by trying to make some of my own tooling... Obviously I have to buy some stuff.

 

[tweinke]

Well now that I tried to blow your budget, in my opinion I would be leaning toward the Smithy just because it comes with more standard accessories. Although you may also want a 4 jaw chuck. Looks to me like the Bolton machines a lot of the accessories that you would want are extras.

 

[aPpYe]

Heh ... I was actually leaning pretty heavily towards the smithy, but today I discovered that they are now offering "free shipping" ... They did this by raising the price of their machines quite a bit beyond what they were previously offering plus shipping. I think they lost my business.

Anyway, I will probably be going for one of the Bolton machines (either AT750 or BT800) because I should now be able to come in way below the smithy prices, even with the optional accessories ... Still haven't decided on that one yet! Anyway, zeroing in pretty well now ...

 

[tweinke]

I notice the BT800 cuts more standard threads. Both machines seem pretty comparable. Kind of a 6 of one half a dozen of the other. I would guess if you can see both machines in person you will make a good decision. Good luck! let us know which one finds its way to your shop.