Is 7mm close enough to 1/4 to work correctly?
Question by imrealldum | last reply
Is 7mm close enough to 1/4 to work correctly?
Question by imrealldum | last reply
Hello, Im trying to see if I can find a replacement bearings so I can try out a larger / better wheel on my knee walker mobility device that has 8 mm bore as opposed to the 7 mm i have now. However after searching the web im still not exactly sure what type I have in order to find a replacement . You can see the bearings below in my photos . http://www.flickr.com/photos/28633046@N02/ ( sorry no zoom in lens ) Any one have any ideas as to what is , and if not what options i have to replace them ? thanks helena
Topic by hele | last reply
I want to thread some tube (since I can't find any to buy in the size I need). I've never used a tap and die before. My pipes are 7mm and 8mm outside diameter, with .45mm wall thickness. I need threads on both sides so they'll screw together. No, I'm not trying to screw the 7mm into the 8mm; I'm just not sure which size will work best. Thanks.
Topic by aliasjanedoe | last reply
Phone is a samsung t319 & the LEDs are TINY! maybe 1mm x .7mm(?) barring any info on a supplier, does anyone know the spex on these little buggers (in case i try to extract them from the phone & use them)?
Question by sagarmothra | last reply
I've been trying to construct a blue laser for my friend using KipKay's instructions, but I don't have a good driver for it. If I add an extra current limiting resistor at the end of it, will this (http://www.dealextreme.com/p/2-7v-6v-3w-cree-circuit-board-for-flashlights-15mm-2-7mm-25518) LED driver provide a good regulated output for my laser? If not what else could I use to regulate the output?
Question by Shagglepuff | last reply
Seeking a source for remnants carbon fiber felt, will use as combination wind screen chimney internal liner to prevent loss of heat to the environment can use piece sized 4 x 24 inches-minimum. thickness 5 mm, 7mm or better if possible. carbon fiber is usually sold by the sq. yd./meter- i know that carbon fiber felt exists but can't seem to locate same, free or cheap is best, thats why i'm looking for remnant material. thanking you for your help big al
Topic by big al 1048 | last reply
Hello instructioners, So i am working on a PCB to use my XBOX 360 power supply as a standard 12volt 16 amp without hacking it apart. I've taken the female plug from a dead Xbox and I've recreated the layout in ExpressPCB. my only issue is being that its 16 amps @ 12volts is the trace widths to hold that much power are ridiculously wide we are talking 7mm or there abouts. I used several different online calculators to determine trace width. My question is.. how small can i get away with for traces and still get 16amps.. is there a way of bridging the front and back side of a 2side PCB to allow for more amperage on smaller traces? i am really at a loss here. since my PCB is set at 38mm by 38mm and the connector size is 27mm long by 23mm wide. with 7mm wide traces i can't connect all the power pins together and all the ground pins together and route them out. Now i realize the 16amps is max draw but i'd like to plan for a max draw situation that way i feel confident enough to not have to check it all the time to make sure its not melting. Below is an image of the current board in Express PCB the labeled Thru-hole are connections i will need to make for this all to work. the other remaining holes are for mounting the female jack securely. The three yellow boxed connections are 12v+ The three greyed boxed connections are gnd ENG is bridged to +5 to make the XBOX PSU provide 12v
Topic by jgosselin | last reply
Hey there, I am thinking of building a quad copter, but am not quite sure, how they work, hopefully someone can clarify this for me. Do all the motors connected run at the same speed, then to move directions you increase the speed of the motor that deals with that direction. For example left control button will increase the speed for the left motor causing it to move left? Also will I be able to get a working prototype using those components below? 4 x 7mm Brushed Motors 4 x propellers. 1 x Arduin UNO 1 x HC-05 Arduino bluetooth module Am planning on dealing with the controls by writing a android app that sends command to the Bluetooth module on the arduino.
Topic by Raphael1 | last reply
We have our car shed roof made from double walled polycarbonate sheets, the problem is that the fabricator at the time of fixing it to the frame forgot to put tape on the holes to avoid dirt getting in. and that time I didn't knew about it, but recently I read this and the dirt has seeped in the holes which are about 7mm square in area. I googled it with various queries but to no avail, Now please help me by giving me some direction and steps to clean it. The dirt is fine sand and some mud which seeped in with rain. I do not want to cut replace or open the sheets just clean them. it has seeped in upto 1.5 feet (roughly half a meter). See the following images, the dirt is just dark areas the rest is just on surface.
Question by MYawar | last reply
I'm weaving Nitinol wire so I have a square piece of plywood with the shape that I'm weaving around placed in the center and the bundle of .7mm Nitinol wire is emanating also from the center. For clamps I used speaker posts that have hand-rotatable post "screw-collars" and are gold-plated. However they're really hard to work with and to mount. They're great because they also have a high-current screw-in wire junction in the back. Anyway, what alternatives can you think of while requiring a hand-turnable release and clamp of the Nitinol wires (so plain terminal blocks won't work unless you also found a screw with a handle that fits). There will be about 20-100 small wires used in the bundle to weave the shape. And the board is about 30cm sq. at the moment so more likely there will be only 20, in order to fit the wire clamps unless you know of a micro method, such as: copper tubes and "nails", which might work now that I think of it...
Question by daniel.donnelly.549 | last reply
Hi All I have looked at a bunch of DIY LED bike/headlamp instr. and would like to give them a try, with my own spin. I just need a litle guidence an some bulbs to match drivers, I don't want to use the BuckPack systems. I will be powering these with a 14.8v or 18.5v li-ion battery system Here is the bulb I think I would like to use. http://www.ebay.com/itm/NEW-Cree-Single-Die-XM-L-LED-T6-w-20mm-Star-Base-/390319928941?pt=LH_DefaultDomain_0&hash;=item5ae0e1766d Now there are different idea's for drivers, with this on can I run 3 of the bulbs on one driver or should I build three drivers? https://www.instructables.com/id/Super-simple-high-power-LED-driver/ Same for these two drivers. https://www.instructables.com/id/Circuits-for-using-High-Power-LED-s/ http://www.dealextreme.com/p/5v-12v-9w-3-cree-3-mode-circuit-board-for-flashlights-16-7mm-5-6mm-25516 This is the driver mode for the last one. https://www.instructables.com/id/Improved-high-power-LED-bike-head-light-with-integ/ Thanks for all your help and the time you all put into this great site!!!
Question by vallka
I am trying to make a magnet levitate between two bismuth plates that i made (picture 3,4,5 and 6). As you can see they are round discs about 7mm (millimeters) thick and 110 mm or 11cm (centimeters) in diameter. I bought two magnets; -the one I am trying to make levitate is 30mm (millimeters) in diameter, 10mm thick, and 22kg (kilograms) strong... -the other that is on top, the one that is pulling the magnet up is 30mm in diameter, 15mm thick and 23kg strong I put my two plates of bismuth so that there is about 25mm of space between them... Than I put in the 30mm x 10mm magnet that I want to levitate inside. The other magnet is located above the setup. I very slowly, ever so carefully start to lower the magnet. The magnet between the two bismuth plates starts to shake and at one point hits the top bismuth plate. I can't make it to levitate, either it is on the bottom plate or on the top. I tried to make the space between two bismuth plates smaller and larger, to lower the magnet by a very small amount...it didn't help... PROBLEM: I can't make it levitate, either it is on the bottom bismuth plate or on the top... WHY IS THIS? HOW CAN I FIX IT AND MAKE IT LEVITATE? Thank you for your help! -Stanislav A.K.A. Comodore
Question by comodore | last reply
Hi - I've been a "member" for 5 years now, but unfortunately never submitted projects... I'm more of an observer than a teacher :) I have this project I've been thinking of for quite some time now, but I simply cannot come up with a way to make it real. It's pretty simple, I just want to be able to light up an extremely small LED in a very small amount of space. But, I'm finding the power source is the headache. I wanted to get input or suggestions from anyone willing to share/help me! Basically, I have a 5mm diameter space (x approx 7mm high) to work with... and this would be to house the LED, power source and any type of on/off control or switch. My initial thoughts were toss in a micro LED, run it off of a wireless coil or super small battery and control it with a magnetic latching switch for on/off control. But, since the original idea popped up, it appears for wireless power the coil would need to be too large to fit in this space. For battery power, I've found very small 1.5V watch batteries that I could stack in a pair for 3V, but I've learned they would likely only run an LED for about 15-20 mins before they'd die. If they were wireless, I'd want some free range of motion and distance on the LEDs, being able to light up at least 6 ft. or so from the power source, if possible. This is driving me crazy! Can it be done, without costing a ton of money to develop?
Topic by djc311 | last reply
Hello everyone I (like alot of my freinds) get tired of... oh why dont you just search "Knex gun" and look at the mini descriptions and read them all, or maybe most and think what alot have us geting tired of, Go ahead! see you in maybe a min or 2? just click back or whatever to return here! and continue from where you last read.Welcome back! Do you see what what I'm talking about? well there are two things and if you did not notice these things feel free to look again!And what is Sypran talking about? (drumroll) the Quotes "It's very powerful" "easy yet powerful knex gun" "gun shoots about 60-70 feet" "this is a very small gun but will fire about 50 feet" "A deadly knex gun" and that is just the first page! i could go on for hours (ok maybe a long time) of coppy and pasteing these quotes!honestly i see to much "easy yet powerfuls" i cant realy tell what is powerful! so what do we do? well we take out time building maybe some and it turns to be not that great or it is great!, or we rush to see if KILLERK, Mepain, Extreme builder, Trainman2000 (i will always call him that >=D)You (aka mykhailo),Perfect duck,loosewire,Dsman19(i cant rember numbers) Oodalumps, am i forgeting anyone? (tell me if i am) has any new ideas/guns.so what do we need to do? WE NEED A FIREPOWER STANDARD something simple like 1-20 and how to mesure it, in earth science they clasify rocks hardnes by what they scratch (nail 2.5 glass 5.5 and so on) we need it something like paper peice, but not that for some guns have alot of power but cant peice due to low velocity and or dull non sharpened bullets.also if you know anything about real guns the bigger the bullet, the more powerful =D but the smaller the bullet the higher peirce rateing (a 0mm would be the best peirce but little damage) so in other words the biger the bullet (45 cal example) the more stoping power it will have but less muzzle velocity (pierceing ability) wile the smaller (7mm) the knocking over/stoping power is anything to be desired, but it will have high muzzle velocity so peirce through more materials. yet with (if it was at all posible) a 0mm (or basicly nothingness) in theory could peirce through ANYTHING but would not stop the person or thing in any way so the same pricable stands for knex notice the shotguns that shoot conectors (or killerks magnum with his amo) create a biger bang sound, they do more damage, but need more force to get all that mass through a paper wile the ones that shoot sharpened (like gorkem's) or greens can peirce paper with ease. so not only will we need a firepower test but a peirce test. peirce is easy enough its velocity and ammo size and a variable if it is sharpend and we have an instructable on how to determin bullet speed. power is bullet size+ extentions (killerk's magnum ammo like) also a little velocitybut the system needs a ruberband standard to keep in mind no putting on more then the systems amount of ruber bands or size of ruber bands (i know people will do this anyway)so what am i basicly saying in this topic? easy please people we need records of bullets speeds for sertain bullets with your guns it is easy since most of you seem to have digital cameras and there is an instructable about it. also we need to know a standard RB cause i dont know whats standard in the rest of the world besides USA and even then i dont know if its standard in the other states (they say americans like everything bigger and sadly sometimes it's true)i have tested some guns out and lets say that stong yet easys from the first page so far are low... so maybe we need a test for difrent kinds of guns! i have seen rifles that fire like a medium pistol (for they are exept they have a longer barrel, bipod, stock, and scope) should these even be given a 6 out of 10 in every catagory? or should it be 2 outa 10 for rifles. if lets say we got a standard of ruberbands to be 2 (not including trigger ruberbands) that where (makeing this up) a circumfrance of 3 inches, end of barrel being 2 feet away from camerathe adverage gun (all makeing up still) 25 feet with white shooting 1 foot per sec, does not dent an empty can. bullet speed of 5 feet per second with a max range of 40 feet (acurate ranges ppl use mesuring tape) with a white bullet that dents and peirce through an empty can we can conclude that the gun has high peirce rate but beter then normal power rateing. so a 7/10 for peirce if best was a max of 60 ft bullet speed of 10 ft per sec and white rods then it could have scored higher.one day when i search "knex gun" i want to see "my first Sniper!, it scored a 7/10 firepower and 8/10 pierce with 100ft range" cause then i can say that is a good gun I'm going to build!
Topic by Sypran | last reply