Just solved this problem on my Solidoodle 3 with Ramps 1.4! I had similar problem. If I looked at a single layer perimeter with a magnifier I could see differences in the line width with bumps spaced very closely together. Drive gear is about 10mm (guess) so if problem was related to drive gear being off center pulse/unevenness would have been every 30mm (pi*d). Next best guess was stepper driby Miamicraft - General
I am also interested in this approach but have not gone past thinking. There needs to another name for this geometry other than polar. The math is pretty simple but the arduino suffers when much computation is required. That is why most serious delta users have gone with 32 bit controllers such a duet and smoothy. The 32 bit software was based on marlin but was completely refactored. You should bby Miamicraft - Polar Machines, SCARA, Robot Arms
Could you please elaborate on dead spot. doesn't have one and there doesn't seam to be one in 5 axis CNC which can use similar strategies. I've done some searching and can't find anything. Thanks, Rogerby Miamicraft - Polar Machines, SCARA, Robot Arms
I haven't seen much development in polar machines (except Polar3d) lately and was wondering why.The mechanical design is trivial as compared to a delta machine and calibration should be no more difficult than a Prusa. Is the problem with the controller and or firmware? The math seems pretty straight forward if you don't take into account having to vary speed and acceleration in relationship toby Miamicraft - Polar Machines, SCARA, Robot Arms
Well... finally getting back to Sintron. It is fully assembled and (temporarily) wired. Still waiting on 32 bit controller board. Fried my Arduino. No problem as I have spares. Very interesting. On my big CNC mill the servo drives light up when I manually back dive the axis with the power off. This happens because the DC servo motors are basically generators. This doesn't cause a problem as tby Miamicraft - Delta Machines
Tha_Reaper, The only way they could make the old rod ends work is to modify the machines geometry. You are likely going to have to change some variables such as Delta Radius to allow calibration. That is part of the reason why I went with the traxxis ends. dc42, I've had good experience with Ramps and Marlin on a couple of machines over the past couple of years on x/y machines. Any problems havby Miamicraft - Delta Machines
Nebbian, Could you please upload your configuration.h file? It could save some time and effort. Rogerby Miamicraft - Delta Machines
Nebbian, I'm just going to throw out some suggestions. May or may not help.... There was an issue reported on Marlin that sounds a lot like what you describe. You might want to load the development version of Marlin (https://github.com/MarlinFirmware/Marlin/tree/1.0.x), merge your config.h and see if that makes any difference. You also might want to do a windiff between the config.h you have anby Miamicraft - Delta Machines
Nebbian, Getting close myself. Two (probably real silly) questions: 1. Did you use the Sintron Marlin firmeware? 2. Did you do the G28 (home) followed by a G29 (auto level) before printing? Sintron's software seems to be set up to handle it. If this didn't work I will just wait for my Duet to arive before proceeding. Rogerby Miamicraft - Delta Machines
Kingoddball, I hope it prints OK for you. My current printer has a .60 nozzle for large prints and it will not print the teeth. I have a .40 but don't want to go through the effort to re-calibrate. The Kossel will have the small nozzle when done. Autodesk Fusion 360 is amazing and it is free. You just download the trial and then register as a hobbiest. The program is every bit as powerful as Invby Miamicraft - Delta Machines
I redrew the Sintron carriage and posted it on Thingyverse as . The original STL was a mess with bad triangles and such that made it impossible to edit. I basically cleaned it up and provided a STEP file. Rogerby Miamicraft - Delta Machines
I had to redesign the Sintron end stop mount to be much thinner to be compatible with the carriage. This redesign required the use of a flat head mounting screw to keep from shorting out the microswitch board. Please see: for the step and stl files. Rogerby Miamicraft - Delta Machines
Nebbian, The lack of end stop adjustment screws on the carriage worried me also but I thought that the end stop distance was now set in software? I have a clean model (stl and step) of the carriage but can't print it without changing the nozzle on my Frankendoodle from a .60 to a .40 to get the belt teeth to print. Guess I could always drill and tap the existing carriages. Thanks for the heads uby Miamicraft - Delta Machines
nebbian, Glad to see you are ahead of me. I got the rods assembled and installed, printed a new end stop holder based off an existing design and published on Thingyverse. To space the rods I used a cut off screw and a t-nut on the side of the track. The screw went through the t-nut and locked to the back of the track. No problem except that the rods are only 220 mm long. At some point I will havby Miamicraft - Delta Machines
For giggles did a search on DLT-180. It looks like a close relative of the Sintron. The assembly instructions show Traxxis type ends and cut belts. The carriages are slightly different with the joint horns centered. Don't know if that would affect clearance. The end stop switches are plain lever micro switches which may be why holes don't line up. Some comments on parts not fitting... surprise sby Miamicraft - Delta Machines
Doug, The DUET Board from Replikeo is on sale for $50. Bought one for $60 including shipping. Will commission machine with the Arduino and upgrade after bugs are worked out. Thanks. Nebbian, Would it be quicker (not easier) to just replace the bearings? Sort of good news is you can get machine up and running as is and change out wheels later. The quality control on this kit really sucks. Believeby Miamicraft - Delta Machines
Nebian, Sorry, about the only thing that worked right out of the box was the carriage. I got my Traxis rod ends today. I am going to use the supplied metal rods with jam nuts. I will use this fixture (on Thingyverse). I have another commitment so won't be working on the Sintron for a couple of days but will keep reading. Hopefully some of you will get ahead of me and solve any outstanding problby Miamicraft - Delta Machines
I was goingto use ball ends and springs as I had on hand. I modified the Sintron carriage to take the ball end by cutting the ears off of nice ball carriage and joining them to the body of the stock extruder. The result looked pretty good but my concern is how far the ball ends ended up being from the track. It would affect he geometry. The assembly can be found here and can be opened and modifieby Miamicraft - Delta Machines
My parts are ABS as acetone affects them? Don't think acetone affects PLA? Rogerby Miamicraft - Delta Machines
Kingoddball, The Sintron carriage is not a standard Kossel part so you won't find anything "off the shelf" that will work. I wonder if you sent a note to customersupport@sintron-hk.com asking for the STL of the two carriage pieces if they would send thby Miamicraft - Delta Machines
I did in a followup. They sent me back this picture of their machine from the front view and said see, there is no problem. The picture I sent them: A lot of things have changed in the month since I ordered this kit. There appears to now be better choices on Ebay for about the same cost. A month ago that wasn't the case. It is possible that I just got a bad kit, but I don't think so after mby Miamicraft - Delta Machines
Nebian, My corners sure didn't fit. Much more than just cleanup. Did you try sliding in an extrusion? Sintron says no problem so maybe mine was just a bad kit. Rogerby Miamicraft - Delta Machines
Letter from Sintron: customersupport 9:42 PM (21 minutes ago) to me Dear Roger. thanks a lot for informing us , and our aim is to improve them to better quality , so your opinion is really important to us !! 1. The corners do not fit the extrusions. You should be able to open one of your kits and slide one of the 2020 extrusions into one of the corner pieces. You can't, they don't fit. i'by Miamicraft - Delta Machines
The ball joints don't fit on the sliders, there is not enough clearance for the larger ball joints. . The solution was to print a 4mm spacer to put between the 2 pieces of the carriage. This in itself isn't an issue if you happen to have a RepRap or laser hanging around (have both). The the potential larger problem is that this affects the machine's geometry. Sintron's customer support isby Miamicraft - Delta Machines
My Kossel kit came with Makerbot 1.2 end stop switches which are normally open. The Kossel documentation says to wire them as being normally closed. The Z probe is shown as normally open. I know how to change the switch polarity in the Marlin config.h code to make the home switches normally open and the Z probe to normally closed. Will I be OK if I do this? I've always used normally closed witby Miamicraft - Delta Machines
Nebbian, I'm not sure it matters if the rods are parallel as the ball ends should have enough free motion not to bind and I don't see how this could affect geometry. Its late here and I'm too tired to think about this clearly. Would appreciate it if anyone else can jump in on this. The twisted belt sounds like a great idea. Easy enough to try. Thanks. kingoddball, You missed the T-nuts for theby Miamicraft - Delta Machines
kingoddball, Could be that the part quality shifts on each kit printed. Scary. My corners would have taken more than just a little shaving. I required a mighty big hammer and some serious pounding. Plastic shavings from one corner. Still easier to just print new corners if you can. Had no issues with slump or extrusion fitting on sides of corner. Rogerby Miamicraft - Delta Machines
kingoddball, The corner pieces can be fixed. I did it but decided to print new ones anyway: 1. Find a heavy rubber mallet (2kg in my case) and drive one of the short 2020 extrusions through the corner. 2. Soak the part and extrusion in hot simmering water. This will allow the part to release from the extrusion (sort of with a little help from the mallet). 3. Tap the both ends of the 2020 extrby Miamicraft - Delta Machines
Floyd, Thanks but it seems like the newer Kossel 2020 parts (Link) had recognized this problem and resolved it. My buddy with solidworks 2014 was unable to fix the part. Seems like too many pieced triangles and self intersections. I was ready to just redraw the part in Fusion 360. Openscad makes lousy STL. Anyway, thanks again. Nebbian, The belts are tightened by sliding the top of the machine (by Miamicraft - Delta Machines
Sorry, build was delayed as a friend of mine needed bathroom cabinets and I spent some time making them. Almost finished, will be back full time by weekend. Last evening I erected the frame, installed the carriages and put together the arms. The holes in the rod ends and the rods are 4mm. The ball ends are very nice. I was worried that the kit did not include include 4mm jam nuts for the rods unby Miamicraft - Delta Machines