servo motor startup speed

[Burkhardt]

 

[fibersport]

Tastech - a picture of the speed reducer I made is on the second page of the link that Burkhardt posted.  

[kgg]

12 hours ago, Tastech said:

As i am also a mechanical engineer i might just make up my own using off the shelf components and maybe just a little machining.

Here is a good link to save you some time when designing your speed reducer and get a pretty accurate estimate of what you design will give you.

https://www.blocklayer.com/pulley-belt

kgg

[dikman]

Tastech, there have been many posts on here regarding building a speed reducer. As you say, not too difficult to cobble something together. 

[Tastech]

15 hours ago, kgg said:

Here is a good link to save you some time when designing your speed reducer and get a pretty accurate estimate of what you design will give you.

https://www.blocklayer.com/pulley-belt

kgg

That is so cool. I love it . Thanks KGG

dikman . I ordered the parts for 1 reducer last night after reading this thread . I have 12 machines with 5 different table variations . I have a plan in mind to make a "universal" type but i might opt for maybe 3 different varieties . I want to make them aesthetically pleasing as well as functional. I will road test the first one to make sure i have the pulley combination correct to suit the machine and base the others on that  I am starting off with a 45mm and a 120mm  pulley combo with my motor at 100 rpm i would be somewhere in the less than one stitch per second range  which is ideal for wingtips and brogue stitching on shoe uppers .    

Edited September 14, 2023 by Tastech
save posting another reply

[fibersport]

I used that pulley calculator too just to see what speed I would be getting.  I also downloaced an app on my phone to use it to measure speed, while probably not perfect, it worked consistently.  My pulleys are, measure on the OD of the pulley, 50, 120, 42 and about 80mm on the machine.  My measured motor speed was 502, my machine speed was about 106 which matches up really close to the pulley calculator.  That gives me about 1.7 stitches per second.  I would like to be able to get slower than that, thinking it's the servo motor start-up speed that's keeping things faster than I would like.

[kgg]

8 hours ago, Tastech said:

I am starting off with a 45mm and a 120mm  pulley combo

Who did you order the 120 mm pulley from?

kgg

8 hours ago, Tastech said:

That is so cool. I love it .

That calculator saves a few of the old remaining brain cells.

kgg 

[fibersport]

I ordered the same pulley combination, got them off of ebay, they came direct from the C country and cost something like $15 for both.  I would have liked to go bigger on th large one but had a tough time finding one that was cheap. 

 

[Tastech]

Who did you order the 120 mm pulley from?

Hey Kgg .I got the pulleys on Ebay here is the link

https://www.ebay.com.au/itm/314035306394?var=612710007766

Now in hindsight i should have got a few more in various sizes just in case . 

I have been using poly belts instead of fixed size V belts . They are a red color ,they come in various diameters can can be cut and joined with a little insert able 2 way plug . Pretty cheap at $3-4 per meter . They stick well to the pulleys therefore no slip and have a fair bit of spring in them so things are always tight . I measure the length i need and deduct 10%.and cut it at that .  So far so good . I don't do astronomical speeds  or use the machines for a very long time .However if i was working a machine in a sweat shop i would go the best belt i could get .

[dikman]

I had the same problem with pulley sizes when I was experimenting with speed reducers. 120mm appears to be the largest a lot of ebay sellers have, and trying to buy anything local was expensive. Fortunately I had a bit of an assortment of old pulleys, which I managed to make useable by sleeving the oversize shaft holes. I used the 45/120mm combo on one machine and also replaced the hand wheel with a larger pulley, this gave me 1 stitch every 3 seconds! Impressive but not very practical.