Today I completed the first real project since completing the SumPod 3D printer. I had it print out 8 self designed brackets and attached them to a shelf made from MDF.  The system works quite well and now I can move ahead and make use of them.

Promised to make a handle for a fellow SumPod builder. here it is:-

I finished off the part I promised to make for someone and its a good job its just prototype, because I did not account well enough for a skim finish to loose he  4 jaw chuck marks. However it should be good enough to prove whether it will work! I have ordered some 304 stainless steel bar 16mm square so the next one will be much less effort!

The pictures below show the project in more detail.

Well since the last set of spinal injections I have been able to get back into the workshops, but the priority was a woodwork project for my granddaughter, Freya namely a kitchen! As soon as that was finished (last week) it was starting on the build of my SUMPOD 3D printer kit which has been both enjoyable as well as testing. Its not yet completed but it will be a tremendous additional facility for my model engineering hobby. The first and main reason I wanted to participate in this relatively new and exciting hobby (which I believe will have a massive impact on society) was to print plastic parts that I could then use for patterns when I cast aluminum. However the SUMPOD offers much, much more.

Due it its substantial build and the quality of the parts, it can be used for cnc work. A Dremel bracket is included in the kit with future additions such as a drag knife, and the ability to machine foams/wood and the like. Like all new and developmental products, modifications to improve performance are a natural progression.

Richard (the designer and owner of SUMPOD) became aware of my model engineering and asked me if I would be prepared to make a prototype of a new part in stainless steel? Being pleased to get back to metal work I readily agreed so a couple of days ago Richard sent me a Google sketch of the part he needed. I then redrew the part using Alibre CAD and sent it back to Richard just to make sure it was ok. With one modification (placing the grub screw on the same plane as the two mounting holes) I made a start.

Now the initial problem was that I only had a large diameter bar (from the local scrap yard) so the first job was to cut a more manageable slice off before cutting it again until I had  a manageable piece to mill into a 15mm square by 16 long block

Tomorrow I will chuck it in a 4 jaw chuck, centre it then turn down one end before drilling 3 different holes. I will update the article after finishing it off tomorrow. We will then see if the prototype works!

Nice to be back to metal shavings though!

Well I have at last something to add to the websites! Whilst waiting for some medical treatment I bought a second hand electric motor from a scrapped mobility scooter. I want to incorporate the frame the motor came in (to suit the rear suspension I have designed) and that means making some stub axles as well as making a method to secure the rear wheels to the axle.

I decided to use the keyway cut on the existing axle the motor is secured too and will broach a matching keyway in the stub axle. Onto the new extension (made in stainless steel) a brass bush is fitted to suit the wheels I have bought. Again a keyway between the stub axle and the brass wheel bush (including cutting one in the plastic wheel) should ensure no slippage. A through bolt will secure the wheel, its bush and the stainless steel stub axle to the existing drive shaft. A plastic cover will hide the bolt (I hope to print these in ABS with the 3D printer I have bought)and have either Freya's initials or full name on each.

I do not have a broaching tool but another model engineer, Hugh, also in Brixham, has recently bought a 2 ton arbor press and set of broaches so he very kindly has said I may use his. I am looking for a set of plans for a similar design to that supplied by Hemingways, but being tight don't want to buy the kit.........if you know of a set then please email me.

Here are a few pictures to make more sense of the work done over the last two days, I must say its great to be back into the workshop though...it seems like a lifetime ago since I was last out there. One problem encountered though was a blot on my accident record! I lifted my full face safety mask to check progress and got a couple of fine pieces of brass in my eye! Stupid boy, but a visit to our cottage hospital in Brixham soon had me checked over and some eye cream to administer for 3 days. What a fool!

So I am typing this one eyed.......great to be back though!

Well I decided to give the lathe a good sort out after the Seal crankshaft. So I replaced the face plate with the three jaw chuck which allowed me to replace a tightening bar I snapped the end off some time ago.

I decided to use stainless steel and it didn't take long to make the bar in the pictures, in fact I surprised  myself how quick it was. I suppose this only emphasis's the complexity of the work I have been doing on the Seal crankshaft.

After buying a DRO unit to replace one that came originally with my lathe some 5 years ago I had some issues getting it to work.

First of all I was buying one from Singapore that advertised it as “Suitable for replacing your faulty scale / using other brand of linear scale/encoder feedback.”

I must admit I was more than a little skeptical but checking their feedback reassured me that they seemed a genuine company. Also the cost, even including shipping from Singapore to the UK for a total of approximately £120 ($200) was £60 cheaper than the original supplier (China) quoted. I decided to go for the cheaper option (twas every thus!).

Whether the aggravation was worth it then I suppose it depends on where you are in the process... When pulling my hair out over the last few days trying to get it to work, then I cursed myself for being a cheapskate (or poor....). Now that it is finally working, I have a bargain!

The positives and negatives of the project from my perspective.

Communications:

Both negative and positive! Peter, the chap I was emailing, always answered emails promptly. However language proved difficult for me even though we kept sending photo’s. If I followed what I thought (not necessarily what Peter meant!) it wouldn’t work. Resulting in several photo’s/diagrams being emailed between us. One major issue revolved around the numbering of pins on the D plug. I was reading the numbers relating to pins to be soldered to the pins to be soldered!!!! No, the pin numbering relates to the front of the plug! Indeed the numbers could be seen when using a Jewelers loupe. I then constructed my own diagram and worked out the colours for each pin from Peters labeling of a photo I sent him showing existing wiring (this was the cause of the breakthrough really). One further fault/frustration was by reading that one pin needed to be soldered and then earthed (or so I think) and when trying the plug the numerals would only change up/down by one digit increase/decrease. In frustration I decided it looked like an earth fault (don’t ask me why!) and I thought &^%$$% it, I’ll cut this earth wire to that pin.

Low and behold, when connecting the plug up it worked!!!!! The second plug was then wired and I had two readings...joy oh what joy. Then I thought that knowing my luck there would be something wrong with the accuracy of each axis. So I set up a dial indicator and checked the readout movement against the dial indicators and all was well, phew! There was a slight difference but I wonder whether in fact this error is in the dial indicator or not...I suspect it is.

So if you do buy one of these DRO’s and you have the same make of scales (see picture) then the methodology highlighted below worked for me.

One major misunderstanding related to the numbering of 9 pin D-sub miniature plugs. The pin numbers relate to the front of the plug whilst you solder to the back! Now I consider that DAFT!

Using a jeweler loupe I saw the numbers on the front side of the plug, then transferred this to a diagram of my own identifying the pins from the rear and allocated the colours to that diagram. I then de-soldered all the wires, so having a clean starting point.

Solution

Remove all wires from D plug and identify the pin numbers (look at the front of the plug). Make your own diagram showing back solder part of pins

• Solder yellow wire to                 pin 9
• Solder Green wire to                  pin 8
• Solder Red  wire to                     pin 7
• Solder Blue wire to                     pin 6
• Solder Black wire to                   pin 2   (you can just leave this one in place if you wish since it doesn’t move)
• Solder back the Earth cable to the body of the plug

This results in a working solution that was not easily seen from Peters diagrams and photo’s but that may be as much to do with me not understanding enough, so I won’t lay all the blame on Peter. If you know more about electronics you may have had no problems!

I have added various photo’s of the steps I took to perhaps help.....If I had the above simple instructions from the start, no doubt it would have gone easily...To be fair to Peter he has asked for this solution so he can add it to his blog for assistance to others.

I have no complaints (now!) with the unit itself. It is far more substantial than the original Bica unit and I would suggest its more the top end of the market, so price seem very reasonable.

Would I do it again? You bet! Would I have done it again yesterday afternoon? No way! So what a difference 24 hours makes.

In summary the unit was certainly not plug ‘n’ play for my make of scales but Peter did help to get it working and that’s fair enough for me. I believe that Peter’s company will supply complete sets with scales and of course that would be a simple fit, and I have promised to fit a set to my refurbished Myford at some time.....but the purse is empty this year so it will have to wait

Well I managed to get out into the workshop this morning to continue on with the Seal con-rods, that's after quickly turning up a bush for the centre of a de-burring wheel. I was impressed with one I saw earlier this week on a visit to nearby model engineer, Hugh's workshop. After trying it out I continue to be impressed, even if they are a little expensive!

Anyway, on to the con-rods. I managed to reduce my steps during the night on machining with the small rotary table. Nevertheless it still took quite some time to refine the measurements and angles required. I think I am nearly there now and whilst I need to improve on my finished sizes (I always allow too much for final finishing. I should be  much braver!) I was pleased that the machining itself went without mishap. No grabbing the metal and climbing t who knows where!  The securing method of the fixture  made seems to have enough grip.

There is still some refinement needed but whatever else I believe I will achieve some accuracy with repeatability. Time as always, will tell. Here are some photo's but I must repeat, they are not finished!!!

One other simple but effective modification was attaching some rubber sheet (bought via eBay - use my link on the main website if you want to help with the running costs of the two sites, it doesn't cost you a thing.) which I used to replace the naff and tired clear thin plastic sheet used before. It works a treat so I may buy some more for the Y axis on the Milling Machine. See what you think.

Constituent parts for the home designed wiper motor power feed.

Well  am almost there with the drawings for the RF25 Milling machine power feed. I believe it may also fit the RF30 but that's only information received via the internet. If you have a RF30 then it would be simple enough to check to see if the casting on the milling table for the handle assembly is 2" in diameter and the two securing bolts are centred x " apart.

A full write up will be on the main website within a couple of days but in the meantime the image shows the constituent parts of my power feed solution. The plans are free to those that want them and I am willing to help with the casting for the wiper motor to table coupling although not on a massive scale!! I am only helping fellow engineers out, I do not run a business (health issue alone rule that out!). In the meantime please email me if you want a little more clarity!.

You need to click on the picture to see the full image

Because I have not been fit enough (and other distractions) I have not spent very much time turning metal (or wood for that matter!) however because I can use the laptop whilst laid up I have been coming to terms with assembles in Alibre 3D CAD. The more I use this program the more impressed I become. That's not to say I haven't had several headaches with learning how to use the assemblies, especially rotating parts that come in on the wrong plane. However, I am getting there! The only difficulty is I am itching to start fabricating the chassis!

Using the photo import facility and measuring against the image I managed to produce a spreadsheet of dimensions. Really useful facility! Anyway, adding a bit of colour helps differentiate between parts so the picture above is my chassis design to date. I found that importing the pillow block bearings is a great time saver and the best website I have found so far for bolts and various other parts (the grease nipple and pillow blocks came from this site) is 3D content central it will save you a lot of time I am sure.

Hopefully I will soon be out there welding away!