Has anyone ever heard of Langmuir

[deakin]

@deakin I have been away from this community for years but am planning to become active again. It would be good to see more discussion of the MR-1 here, in a vendor neutral context.

Have you looked at the discussion of MR-1 mods in the langmuir forums? I think casters / some provision for moving the machine is a must. If I had to do it again, I would modify the kit supplied drains.

curious why i would need to move it around??

and modify drains in what manner?
thnks

 

[keeena]

I saw the MR-1 when they announced the pre-sale/deposits quite a while back. It seemed reasonably impressive (considering what it is and what it isnt), but that was based on marketing materials/videos. I'm very interested to see how the machines work out for you guys.

 

[pontiac428]

The MR-1 is an oddball hybrid DIY router machine being marketed as a cheap alternative to already cheap alternatives to CNC manufacturing. I think Tormach has filled the gap between hobby/small-scale and production-scale by offering affordable imported turn-key machining centers. Now Langmuir is doubling down on the gap between Tormach and the DIY level, which is, in my opinion, a very awkward market sector. Gantry mills are awkward machines already with numerous limitations, but can do good work when run slow-and-low. So as interesting as I find this topic, I wonder what people's realistic expectations are, and how much is really gained by buying this class of machine as turn-key as opposed to a custom build. Interesting discussion.

Full disclosure, I've worked with DIY CNC and find it not very difficult. I also purchased but haven't spent much time with a Langmuir turn-key plasma table, so I am very familiar with the company and am up on their latest merger. So I'm not totally trolling here.

It seemed reasonably impressive (considering what it is and what it isnt), but that was based on marketing materials/videos.

This! The mere mention of "what it is and what it isn't" tells me you have a clear picture of what these machines can do. I think there are people out there that think this is a poor-man's VMC, but it's a different tool entirely.

 

[dogma]

The MR-1 is an oddball hybrid DIY router machine being marketed as a cheap alternative to already cheap alternatives to CNC manufacturing. I think Tormach has filled the gap between hobby/small-scale and production-scale by offering affordable imported turn-key machining centers. Now Langmuir is doubling down on the gap between Tormach and the DIY level, which is, in my opinion, a very awkward market sector. Gantry mills are awkward machines already with numerous limitations, but can do good work when run slow-and-low.

My expectations are that it will be able to cut aluminum and mild steel plate but at low speeds. I was specifically interested in the machine because it was A) cheap and B) could machine 20x20 plates (single setup) for other projects like 3d printer bases. Now that I have discovered sendcutsend, which is much cheaper than local waterjet, B isn't as exciting anymore.

The low gantry is actually a major pita. More specifically, there is only 2" of travel in the Z axis above the bottom of the gantry, which is really limiting for tools. The 6" max setup height would be a lot less of an issue for me if there was another 6" of travel in the Z.

The spindle has a ton of power (2.75hp) but at the recommended max F&S and DoC (because if low rigidity), it is hard to use even 1HP of it.

That said, it is a low cost to entry that fits in a garage with 8' doors. A tormach 1100mx with an ATC is now pushing $40k after sales tax.

 

[dogma]

Tormach prices have risen to the point that there is now a market gap. As a beginner, I don't want to gamble on refurbishing a 20 year old VMC (a project that might never be finished) and it is hard to fork over the cost of a new car for a machine as limited as a tormach.

 

[dogma]

curious why i would need to move it around??

Well, did your home come with a mill?

There isn't a good way to install lifting eyes. So the options are a fork lift or other height lifting table, putting it on a pallet that can then be moved with a pallet jack/etc. Or putting leveling casters on it (my choice). I haven't yet moved it from where I poured the base but I'm planning to.

and modify drains in what manner?
thnks

The drains in the lit have an injected molded tabs that are screwed to the side of the chip tray. There is a molded in weak V notch to make the tabs easy to break off after the slab is cured. Because of this engineered weak point, the drains don't sit level and will be pushed around when packing concrete around them.

I also think the drain screens don't have enough surface area and trivially pack with chips. In the langmuir forums, there are a bunch of mods people are trying

 

[DavidR8]

The low gantry is actually a major pita. More specifically, there is only 2" of travel in the Z axis above the bottom of the gantry, which is really limiting for tools. The 6" max setup height would be a lot less of an issue for me if there was another 6" of travel in the Z.

The Z clearance on the PrintNC is also an issue for some folks even though it's like 4'ish inches.
Some have modified the design to add 2" of Z height with an accompanying loss of rigidity due to the increased lever arm. Trade-offs always have to be made.
I suspect a similar mod could be done to the Langmuir mill with the same effect on rigidity.

 

[dogma]

I suspect a similar mod could be done to the Langmuir mill with the same effect on rigidity.

There are two paths to achieve this . One would be to block up the Y-axis rails. This is easy to do poorly but trying to maintain some rigidity would require machine a full length rail to install under the existing rail with holes bored in to attach to the side "stabilizer" plates which are embedded in the concrete.

Any time the y axis rails are touched required recalibrating the offset between the two y ball screws to avoid racking the gantry. This is fiddly but more time consuming than difficult.

The other approach would be to rebuild the Z axis with a longer acme screw (yes, acme. The other axes use ball screws) and linear rails.

Spindle tramming is a nightmare and is done by lifting up the > 100# x/z carriage and inserting shims. An inspection card is provided with data you input into an online calculator for the initial shims to install. The result is "meh" but I haven't tried to improve on it yet as it is a twoan job. This needs to be solved before sorting out a lengthened z-axis.

 

[DavidR8]

There are two paths to achieve this . One would be to block up the Y-axis rails. This is easy to do poorly but trying to maintain some rigidity would require machine a full length rail to install under the existing rail with holes bored in to attach to the side "stabilizer" plates which are embedded in the concrete.

Any time the y axis rails are touched required recalibrating the offset between the two y ball screws to avoid racking the gantry. This is fiddly but more time consuming than difficult.

The other approach would be to rebuild the Z axis with a longer acme screw (yes, acme. The other axes use ball screws) and linear rails.

Spindle tramming is a nightmare and is done by lifting up the > 100# x/z carriage and inserting shims. An inspection card is provided which data you input into an online calculator for the initial shims to install. The result is "meh" but I haven't tried to improve on it yet as it is a twoan job. This needs to be solved before sorting out a lengthened z-axis.

I can imagine tramming is not an easy process.
In contrast tramming my PrintNC is a matter of turning some captured SHCS that bear against backing plates. Easy peasy.

 

[deakin]

Well, did your home come with a mill?

There isn't a good way to install lifting eyes. So the options are a fork lift or other height lifting table, putting it on a pallet that can then be moved with a pallet jack/etc. Or putting leveling casters on it (my choice). I haven't yet moved it from where I poured the base but I'm planning to.

ok understand. i don't have that problem tho'