Member postings for Michael Checkley

Making a negative mould is very interesting! as this would make multiples cost effective.

3D printing brings manufacturing readily in to peoples homes and once CAD is learned is very simple and relatively cheap. If casting aluminium patterns was an outsourced job it would be far too expensive and likely go on the CNC milling machine as machining aluminium is cheap - obviously machining steel and cast iron is a different story.

....if you can do everything yourself then the only cost is your time....

I recently took part in a study to compare a few different additive manufacturing techniques with the aim to finding the best solution for prototyping injection moulded mechanism parts - The result just proved what we already knew and had been doing for years...STL

The output of FDM is well documented now and didnt score highly in this exercise. Visible steps and lack of ability to print fine detail meant some of the parts were not usable. I have an Ultimaker at home so was not surprised by the result however I was pleasantly surprised at how good the Ultimaker prints compared to the more industrial machines....very much user dependant!

By far the most usable was STL. These produced smooth parts with an accuracy or ~0.1mm which is in the ball park of injection moulding. The parts went together well and the job was done. Even parts done on the desktop Formlabs machine gave good results. The tough resin produced good functional parts for some of the wearable parts we were looking at.

I purchased my Ultimaker for strong functional parts for model aircraft but for model engineering and scale detail I would go with STL, probably a Formlabs machine - as seen in the Hornby series on TV.

I heard that changing resin and clean up of the machine is a pain? how practical is it to do a single small print compared to FDM.

Obviously the material is sensitive to UV so how well does it perform outdoors all day? assuming painting helps here? I currently outsource all my STL prints for work and have been advised to not leave them by the window for more than a few hours as this will degrade properties.

Lost wax prints are very popular at the moment and outsourcing 3D prints is expensive because the process is slow and raw material costs are high so printing your own pattern may save money but we should not forget the casting knowledge required to produce a good pattern so some level of learning should be expected before receiving wonderful usable lost wax castings - probably scope for another article!

Hi Keith, your name sounds familiar??....I used to live on the Wirral and was a member of the WRCFS (model flying club) for a number of years. We have since moved to Tarporley. Being self employed, 2 children and a house move has taken its toll on the model flying but my model engineering still lives on as its easier to escape to the bottom of the garden than the flying field!

My father is a member of the Wirral Model Engineering Society if you need any contacts then please let me know but they have a good website and Facebook page and active most weekends on the ground level track.

Mike

I thought it was worth concluding this post as it may help others...

My mission to find someone to roll my front wheel tyres came to a successful end and Newbrook Engineering Ltd helped me out and did a good job. Thankyou for the recommendation Densleigh!

Newbrook (Crewe) are local to me so I`m sure I`ll be calling in again.

Thankyou for the offer Andrew! your post has given me the now obvious idea of seeking out my local model engineering club. My excuse is that we have only just moved in to the area!

I know I should but I cant see me doing much rolling of this thickness again....never say never

I thought the guy I used was going to cut them back after rolling adding the angle but clearly they just lasered them out as is hoping for the best.

Edited By Michael Checkley on 23/12/2021 12:09:48

Edited By JasonB on 23/12/2021 15:08:00

Hi Noel, I live in Tarporley, Cheshire.

The job that has come up next is for 40mm x 5mm front wheel tyres for my traction engine project. I do not own bending rolls so the choice was to either buy some or get the job done outside.

I failed miserably by trying to be too clever and providing a drawing and DXF so they could laser cut the fixing holes all nicely spaced as well as the profile. I did discuss with them making them oversize and cutting them back but unfortunately they didnt and I was left with flats on the ends.

I have since learned and put together a far simpler drawing which shows an over length curve just from stock flat strip and I`ll cut out the good curvy bit.

It would be useful to build a relationship with a business that is happy to do these ad-hoc small jobs as I often get asked in work life to do small jobs that are usually too big for me! I have a great network of aerospace suppliers but they all come with aerospace price tags.

I`ll put the drawing up....

Hi Mark,

Charles Watts has come up before so I may give them a shout. Finding someone local would be ideal to cut out the postage cost but around me is mostly agricultural so I am not sure on what the end result will be like.

I have recently had what I thought was a simple job done by a local fab shop who I have used for years both for myself and for work and they made a complete mess of what I thought was a simple job.

Morning!

Can anyone recommend a model engineering supplier or person who is happy to help with one off engineering jobs please? paid of course.

Jobs will be more fabrication type work (rolling, welding) which is beyond the capabilities of my workshop.

Thanks in advance

Regards

Mike

Do you have a link to FAQ? I cannot find it on their website. Hopefully peoples efforts wont be wasted but currently if used its without approval and may never get it. On the other hand it could provide vital assistance to care workers who are not necessarily NHS staff and some literally have nothing in the form or PPE.

I have also seen requests for support on places like LinkedIn and having all the tools to assist I have been thinking about how I can also do my bit. However, does anyone know if this "stuff" will actually make it to our NHS staff? or will it end up in landfill or sold abroad? I have heard stories of piles of donated PPE that cannot be used as it does not meet the requirements. Next years documentaries are probably being written as we speak.

Having worked on a few medical equipment projects I know that it can take as much effort to get through qualification as it did to design the thing in the first place. If I was handed a homemade face mask to wear either on a ward or in a car park doing routine checks I`m not sure I would be that happy. I suppose its better than nothing but they don't have nothing its out there, somewhere, waiting to be distributed. The impression I have is that we have enough PPE in the UK its just in the wrong place and getting moved about more promptly now.

Perhaps someone that knows first hand can clarify as I would be happy for my Ultimaker to be working day and night if it was going to good use.

Mike

16 different programs and a good few tool changes later and the first slave rod is ready for bushes. Thankfully I need 4 which will make use of the progams and jigs.

Slitting saw works ok. A fixture to machine the newly cut face is required next.

Edited By Michael Checkley on 02/01/2018 18:49:57

I think the pins need a bit more thought and I’ll see what I can achieve with the heat treatment kit that I have in the workshop. The plan is to have floating pins with PTFE plugs which seems to be the most common approach with model aero engines.

Low profile slitting saw finished and ready to slice off the conrod from the blank.

Hi Neil,

Thanks for info on the pins. I have used the shoulder screws so far but not completely sold on the idea as the tolerance on the shoulder was wider than expected. Can you provide some more details for the tool steel please? Is that grade available in various diameters? I have had a quick look online and not found much.

Hi Jon,

I looked at the zenoah crank and there are a couple of differences and after searching the chainsaw/scooter market I eventually gave up and decided to make one from scratch.

From what I heard Neil has the original Corsair with an equivalent 150cc engine. It would seem like a good engine to add to the range given the interest in radials at the moment. I think it will only be the cylinder heads that fly again from the original engine given the rework that would have been required and replacement of a few missing bits.

Edited By Michael Checkley on 24/12/2017 20:57:01

The new 16mm milling cutter from Greenwood tools made short work of roughing out the conrod, only trouble is I didn’t leave enough height to get the slitting saw in so it’s either start again with new blanks or make a low profile slitting saw arbor. I think the arbor may come in handy for future jobs.....

I have been using Glanze tools from Chronos, 8mm square in a AA size Multifix tool holder for my emco compact 8. So far very pleased with the aluminium inserts for turning, facing and boring, I have not used the other inserts on steel much yet.

Hi Dave,

I’m not sure how well the shoulder bolts will do the job but worth a go. The original plan was to use rollers from roller bearings, readily available and quite cheap but only available solid and I want to keep the mass down on the moving bits!

Pistons have all been milled and drilled and the bolts cut down and hollowed out to make the pins. Rapidly running out of 5 off parts to make