# Rubber belt moving vs Screw servo driven motion



## allamerican-aeoon (Aug 14, 2007)

Many dtg makers are using rubber type belt moving platen system. Coated with teflon belt is often used. When dtg users are fighting with one pixel rubber will deliver tens of pixel shrink and stretch. By temp' and by using a over times. This means off registration big time. Will not win any contest or customers who is very picky these days.

Teflon coated stainless solid screw will stay as it is almost forever. I am sure live longer than anybody who read this. No stretch and wear and tear but only problem is cost 50 times more than thin teflon belt.


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## 102557 (Mar 6, 2010)

Screw drives are not all created equal and they have there advantages disadvantages aswell.. backlash nuts etc, binding in colder weather and more... must be lubricated etc etc.. screw drives dont do very well in harsh enviroments with alot of particles in the air that can bind it up.. (say a production floor with alot of lint etc) this is a big issue with cnc machines that mill metal/plastic (that are worked hard every day).. the particles either bind or chew up the screw drives and tends to need to be maintained more and or replaced which is alot more expensive than replacing a belt!! the machine end user can generally replace a belt far easier than dismantling a machine and replacing a screw drive aswell.. (reducing down time)

the t-jet 3 had many problems with a screw drive and registration... regarding the backlash nut.. spiderx1 can attest to this!!! As with any machine it depends on its deisign parts/qaulity and whom built it..

simply saying a screw drive is better is pretty bold depends on alot of things regarding the application, some very good cnc machines are belt driven and most newer cars use a timing belt amongst others, these belts in cars endure extreme temps hot to cold and varying horsepower and torque.. this just goes to show some of the top engineers prefer belts over gears/chains... there are many different qauilitys of belts also some material examples are rubber/neoprene/polyurethane/ urethane some of there tensioning materials are fiberglass/kevlar/polyester/steel etc... also dont forget you have rack and pinion and friction drive which is the best Imho (like epson uses) Keep in mind every epson carriage is driven by a belt drive with perfect accuracy over 13 or 17 print area some more, so if the belt is prone to fail it would fail there first then. no? I really dont see the point to over building a printer that has similar belt drive parts that could fail? to me thats like putting a porsche engine on a chain driven go cart, where one parts strength isnt going to benefit the overall system. theres a bigger chance of other belts/parts (carriage drive) failing first... maybe a ground up build not using an epson platform would be the better application to adding expensive parts.. what drive system does the aeoon have?

Here is a friction drive i would love to see on a commercial dtg... Precision Linear Drive this would deserve some bragging rights..lol  IMHO on a qauility built dtg there is no real advantage between screw and belt drive they both have a degree of backlash to work with/overcome and there positive/negatives.. the above friction drive (backlash free would be something to see on a commercial dtg)..


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## zoom_monster (Sep 20, 2006)

allamerican said:


> Many dtg makers are using rubber type belt moving platen system. Coated with teflon belt is often used. When dtg users are fighting with one pixel rubber will deliver tens of pixel shrink and stretch. By temp' and by using a over times. This means off registration big time. Will not win any contest or customers who is very picky these days.
> 
> Teflon coated stainless solid screw will stay as it is almost forever. I am sure live longer than anybody who read this. No stretch and wear and tear but only problem is cost 50 times more than thin teflon belt.


Peter, while I see what you are talking about, the actual "registation" is done optically. If care is taken to protect that system and to make sure that the "home point" is stable, it should not matter. Yes, belts can loosen over time but the drive motor (the more expensive part) will probably last longer.


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## Resolute DTG (Jun 27, 2010)

I have experience with the t-jet 3 / blazer pro / blazer express all using screw drives. In my opinion they all suffered very quickly from general wear and tear.

The pro was a long drive and suffered from heat expansion.

Twin belts are the best method I have seen, this allows for an even distribution of weight between the belts not just on one central belt. If you optically align the shirt carrier with the original 4880 sensor on the carriage it should be good every time.


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## JohnL (Nov 23, 2010)

Many of the points listed above are valid. I think Peter is going off of feedback we are receiving from our customer base as we have yet to replace any of the drive screws in use by our NeoFlex systems. So please forgive him as his assumptions may be biased due to this reason. 

Nothing is perfect but we feel that the drive screw will indeed give repeatability as well as durability, which is why we chose to go this route even with the added expense. Many things were considered but in the end the engineers seemed to have steered us in the right direction.

German you seem to know a great deal about cars. Can you tell me why changing my timing belt and water pump costs me so much!!!


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