Hi Craig - My search for small harmonic drives continues. The planatary I'm looking at has 30arc min backlash (from stepperonline, a couple of years ago they used to be 10 arc min). I'm going to use...
Type: Posts; User: peteeng
Hi Craig - My search for small harmonic drives continues. The planatary I'm looking at has 30arc min backlash (from stepperonline, a couple of years ago they used to be 10 arc min). I'm going to use...
Hi All - The board is now finished and tested. Straight cuts - all good! Peter
Evening all - a small video on my B axis design - Peter
https://www.facebook.com/ScootCNC/videos/973453794343621
Hi Lozz - Can be all of what you mention. Since the machine cuts well slow lets assume we can speed it up. Looking at the cutting data firstly with such a small bit I'd be running it flat out maybe....
Hi Spot - I have several slabs around my house for garages and sheds etc they are 200mm thick and have cracked since laid say 2 years old & I thought the contractor used a lot of reo in them. Here's...
Hi Spot - You maybe doing some stuff right and that will come out when you have a machine running. I only point out stuff that is clearly incorrect in your language, understanding and explanations of...
Hi Spot - Again sorry - the fibre composite industry has very specific definitions of weaving, knitting and tape laying,. I have been involved in all of these. The machine in the video is a tape...
Sorry Spot - Weaving, knitting and tape laying are totally different processes. It is NOT a sewing machine and it is not knitting or weaving. You'll get there one day. Plus if you load a structure...
Hi Qing - Connecting motors in a parallel has issues. I presume by your statement that you want to connect two motors from one driver. Since your making a printer use a printer controller board. Much...
Again Spot - What are the $/kg steel and $/kg concrete you used? I don't want to argue with your costs I want to know the cost ratio to check your comparisons. Peter
Hi Spot - aircraft and high performance boats do NOT use woven mat. They use straight fibres at a fibre volume ratio of around 55-60% so they have space around them for the resin. Really modern stuff...
"fibres need to be in contact with other fibres to have tensile strength" absolutely wrong. I have spliced many ropes and that is a totally different game to fibre composites. Aircraft wings and...
Hi Spot - If your doing manual maths then usually we use the resistor sum analogy for calculating the compliance. So use series or parallel resistor theory or network to calculate the compliance. If...
Hi spot a large scale printer - Peter
UMaine’s novel polymer 3D printer surpasses former Guinness World Record | CompositesWorld
Evening all - I have been working on a B axis for Lanky and Epoch. I'm in the design polishing stage at the moment after a week of chasing my tail with lock nuts... But it has come together and now...
Hi Keith - I recommend you go with something like a kflop controller all in one box much easier then creating a system from individual parts... and the support is excellent......
Hi GB - Look up Digory
https://www.sciencedaily.com/releases/2021/04/210414154935.htm calcium phospate and silicon dioxide (quartz or sand) in resin.... What is the hardness of ivory and what...
Hi Spot - What is the point of burying a steel spaceframe in a concrete casing? One of the structures will be dominate. The steel being 200Gpa will provide a preferred loadpath and the 30GPa concrete...
Hi Spot - Bambergs work is very good as a general guide but IMO not good for some of the details. Being a thesis and ending in a machine being built it seems to me some decisions where made that went...
Hi Thomas - You will be able to calculate the stress in the beam at the applied load. From concrete data you will find a typical tensile stress of the material. Here's a grout with a flexural...
Hi Thomas - I think testing in opposite directions is a good idea. What is the biggest size of aggregate? Add stress to the spreadsheet so you have an estimate of breaking. Peter
Specific Beam...
Hi Thomas - if you have FE then model your test and figure out some estimated deflections and loads. You probably have some sort of strength figure in the data somewhere? Being linear and if your...
Hi Thomas - Knowledge has no order. Peter
Another Board - I've been wanting to make a board with a guide post so people cut bread straight. So I finally got around to starting one. I'll call it the mitre board. Today I profiled it and cut...
Hi All - Although this is the Milli thread I'll chuck some of Epoch into it as Epoch is the proto Milli 5 axis mill. I have started detailing the tilting B axis so have looked at the plate that I'll...
Hi - The Scoot on that page is a couple of versions old. The main specs are the same I have extended the Z to 320mm lately. The page is due for an update. The machine base is now made from pressed...
Hi Spot - My steel uses E=210Gpa that's the only difference. I agree that the mesh density for the purposes of deflections should not be critical. But once I understand what Fusion is doing then I'm...
Morning All - over coffeee I had a further play with the tube model. I made the mesh finer and used an adaptive mesh setting. Plus I set the connections at bonded. This took more time to solve (due...
Morning All - This morning I refined the mesh, used "offset bonds" vs bonded and the result is much better. I also made the cross areas much closer. So now I would be happy to progress to a more...
Hi Spot - to illustrate the point. I modelled three steel tubes in fusion. The tube is OD45 and ID 35. The rod has the same area so is 28.3mm dia. One tube consists of three pieces so in the...